Structure/epitope-based immunoinformatics analysis of structural proteins of 2019 novel coronavirus

doi:10.21203/rs.3.rs-50740/v1

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Structure/epitope-based immunoinformatics analysis of structural proteins of 2019 novel coronavirus

https://doi.org/10.21203/rs.3.rs-50740/v1

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The newly identified 2019 novel coronavirus (2019-nCoV) has caused more than 81,400 laboratory-confirmed human infections, including 3261 deaths, posing a serious threat to human health. Currently, however, there is no specific antiviral treatment or vaccine. To identify immunodominant peptides for designing global peptide vaccine for combating the infections caused by 2019-nCoV, the structure and immunogenicity of 2019-nCoV structural protein were analyzed by bioinformatics tools. 33 B-cell epitopes and 39 T-cell epitopes were determined in four structural proteins via different immunoinformatic tools in which include spike protein (22 B-cell epitopes, 25 T-cell epitopes ), nucleocapsid protein (7 B-cell epitopes, 6 T-cell epitopes), membrane protein (2 B-cell epitopes, 7 T-cell epitopes), and envelope protein (2 B-cell epitopes, 1T-cell epitopes), respectively. The proportion of epitope residues in primary sequence was used to determine the antigenicity and immunogenicity of proteins. The envelope protein has the largest antigenicity in which residue coverage of B-cell epitopes is 24%. The membrane protein possesses the largest immunogenicity in which residue coverage of T-cell epitopes is 55.86%. The reason that immune storm was caused by 2019-nCoV maybe that the membrane and envelope protein expressed plentifully in cell infected. Further, studies involving experimental validation of these predicted epitopes is warranted to ensure the potential of B-cells and T-cells stimulation for their effective use as vaccine candidates. These findings provide the basis for starting further studies on the pathogenesis, and optimizing the design of diagnostic, antiviral and vaccination strategies for this emerging infection.

Epidemiology

Infectious Diseases

2019-nCoV

Structural protein

B-cell epitope

T-cell epitope

Prediction

A novel coronavirus (2019-nCoV) associated with human to human transmission and severe human infection has been recently reported from the city of Wuhan in Hubei province in China [1]. The ongoing outbreak of a novel coronavirus (2019-nCoV) causes great global concerns. Based on the advice of the International Health Regulations Emergency Committee and the fact that to date 24 other countries also reported cases, the WHO Director-General declared that the outbreak of 2019-nCoV constitutes a Public Health Emergency of International Concern on 30 January 2020 [2]. A total of 1,320 confirmed and 1,965 suspect cases were reported up to 25 January 2020; of the confirmed cases 237 were severely ill and 41 had died [3]. Currently, however, there is no specific antiviral treatment or vaccine [4].

Vaccines play a crucial role in providing protection against a particular disease to host organism, therefore it provides help in saving millions of lives annually across the globe [5]. Vaccine development processes has depended entirely upon experimental techniques, being generally very laborious and time-consuming [6]. There has been much encroachment in the area of computational biology that aids many types of research and helps in diminishing the expected time consumption [7]. Further combination of various bioinformatics prediction methods could significantly increase the prediction accuracy [8]. Thus bioinformatics studies could provide reliable guidance in selecting specific immunogenic epitopes, which will be significant for vaccine design, epitope mapping and antibody studies.

Coronavirus is a class of enveloped RNA virus with a 27–3 l kb long single-stranded positive-sense genome [9]. The region downstream of ORF1 contains at least 10 small ORFs, encoding the spike protein (S protein), small envelope protein (E protein), membrane protein (M protein), nucleocapsid protein (N protein) and the assumed nonstructural proteins [10]. The genome is packed inside a helical capsid formed by the nucleocapsid protein (N) and further surrounded by an envelope [11]. Associated with the viral envelope are at least three structural proteins: The membrane protein (M) and the envelope protein (E) are involved in virus assembly, whereas the spike protein (S) mediates virus entry into hosT-cells, which are essential for viral assembly [4].

In the present study, we analyzed the CoV structural protein's sequence and 3D structures by using bioinformatics methods. B-cell epitopes and T-cell epitopes of structural protein were determined ultimately via different bioinformatic tools. our study will be beneficial for the diagnosis and treatme nt of 2019-nCoV infection and the effective epitope-based vaccine design.

2.1. Sequence retrieval and physiochemical analysis

The structural protein sequence were obtained from the GenBank Nucleotide with the accession number of MN975262. The homologous amino acid sequences were selected by BLAST in NCBI (http://blast.ncbi.nlm.nih.gov/Blast.cgi). The multiple alignment of homologous amino acid sequences was performed using Clustal X 2.1 program [12]. Physicochemical analysis of the protein sequences was predicted by ProtParam (http://web.expasy.org/protparam/), including molecular weight, amino acid composition, negatively charged residues (Asp + Glu), positively charged residues (Arg + Lys), theoretical isoelectric point pI, aliphatic index, grand average of hydropathicity (GRAVY) and instability index of proteins [13].

2.2. Tertiary structure prediction and validation

Homology modeling was used for constructing the tertiary structure of proteins. The homologous templates suitable for proteins were selected by PSI-BLAST server and SWISS-MODEL server [14]. The best template was retrieved from the results of previous methods, which were based on the high score, lower e-value, and maximum sequence identity. Tertiary structure was constructed by MODELLER v9.20 [15]. The Ramachandran plot for all the models was generated, showing the majority of the protein residues in the favored regions, allowed regions and disallowed regions [16].

2.3. In silico prediction of B-cell epitopes

Dozens of B-cell antigen epitopes have been discovered following various algorithms, offering us multiple reliable means of predicting the antigen's hydrophilic regions, accessibility, flexibility and antigenic solubility [17]. We adopted the B-cell epitope prediction method based on machine learning and comprehensively used DNAStar, BepiPred 1.0 server, and COBEP to predict the common epitopes of protein. In the DNAStar, hydrophilicity, flexibility, accessibility, and antigenicity of the amino acid sequence were chosen as parameters for B-cell Epitopes [18]. The amino acid sequence is provided for the BepiPred 1.0 server. We used 0.35 as the threshold. Scores beyond 0.35 account for potential epitote, and a higher score indicates a higer probability of the existing epitope [19]. COBEP are developed based on support vector machine, combining tripeptide similarity and propensity score predicted B-cell epitope [20]. The consensus epitopes were accurate through combining the results of the three tools as the predicting results of B-cell epitopes. B-cell epitopes were selected further for the ultimate results of B-cell epitopes through excluding the amino acid of protein structure internal. B-cell epitopes predicted by computational tools were mapped on linear sequence and on the three dimensional model of structural protein to confirm their position.

2.4. In silico prediction of T-cell epitopes

T-cell epitopes are principally predicted on the basis of identifying the binding of amino acid fragments to the MHC complexes that can activate T-cells. The binding strength of each peptide to the given MHC is estimated by NetMHCII 2.2 at a set threshold level. Given the MHC alleles have tens of thousands of kinds, in order to ensure the representative and reliability prediction results, we selected the most common MHC in the population to predict their peptide binding activity with protein, including HLA-DR, HLA-DQ, and HLA-DP. HLA-DR 101, HLA-DR 301, HLA-DR 401 and HLADR 501 were used to predict HLA-DR-based T-cell epitope. HLA-DQA10102-DQB10502, HLA-DQA10201-DQB10301, HLA-DQA10501-DQB10302, and HLA-DQA10601-DQB10402 were used to predict HLA-DQ based T-cell epitope prediction. HLA-DPA10103-DPB10601, HLA-DPA10201-DPB10101, HLA-DPA10201-DPB10501, and HLA-DPA10301-DPB10402 were used to predict HLA-DP based T-cell epitope prediction. If the predicting results of all four alleles were non epitope, then the consensus result was 0% T-cell epitopes：if the results were only one or no non-epitope, the consensus result was 75 or 100% T-cell epitopes, respectively [21]. Ultimately, the results that consensus epitope result was 75 or 100% were determined as the ultimate epitope results [22]. As a result, the ultimate consensus T-cell epitope results were obtained by combining the results of the HLA-DR alleles epitopes, HLA-DQ alleles epitopes, and HLA-DP alleles epitopes.

3.1. Physiochemical analysis of structural protein of 2019-nCoV

The complete genome sequence of 2019-nCoV was available at GenBank accession (No.MN975262). The 2019-nCoV includes four structural proteins that are required to drive cytoplasmic viral assembly: S protein, M protein, N protein and E protein. The characterization of physicochemical attributes of antigenic proteins was a major step discerning the information about the biological activity of viral protein sequences [23]. Physicochemical analysis of the structural proteins was performed by ProtParam such as instability index, extinction coefficient, GRAVY, aliphatic index, theoretical pI of the protein sequences of 2019-nCoV (Table 1). The results show that The S protein is a large protein of 1273 amino acids, with a molecular weight of 141.2 kDa and a theoretical pI of 6.24. The M protein and N protein had 222 and 419 amino acids, with a molecular weight of 25.2 and 45.6 kDa and a theoretical Pi of 9.5 and 10.1. The CoV E protein is a short protein of 75 amino acids, ranging from 8.4 kDa in size. Instability index of four structural protein is 30-60, meaning that all structural proteins of 2019-nCoV are stable. The Aliphatic index and Grand average of hydropathicity (GRAVY) are 50-120 and -1 to 2, respectively. The GRAVY of S protein and N protein is negative, meaning they exhibited hydrophilic character. The M protein and E protein of 2019-nCoV exhibited hydrophilic character. The physicochemical character may provide a selective advantage in the infected host [24].

3.2. Structure and antigenicity of structural proteins

S protein

The spike forms large protrusions from the virus surface, giving coronaviruses the appearance of having crowns (hence their name; corona in Latin means crown). In addition to mediating virus entry, the spike is a critical determinant of viral host range and tissue tropism and a major inducer of host immune responses [25]. The coronavirus S protein is a multifunctional molecular machine that mediates coronavirus entry into hosT-cells [25]. Homology modeling can construct a target structure on the basis of suitable templates extracted from homologous sequences [26]. Since S protein structure is not available in the PDB molecular database, we used S protein of SARS-CoV as template to predict the 3D structure of 2019-nCoV S protein through the SWISS-MODEL server and MODELLER software. The results revealed that the S protein of 2019-nCoV is a clove-shaped trimer with three S1 heads and a trimeric S2 stalk (Figure 1A). Monomer of S protein comprised of S1 and S2 subunits (Figure 1B). The S1 subunit contains a signal peptide, followed by N-terminal domain (NTD) and C-terminal domain (S1-CTD) (Figure 1C). S1-CTD contains a receptor-binding motif, which presents a gently concave outer surface to bind ACE2 (Figure 2A). The S2 subunit contains conserved fusion peptide, heptad repeat, transmembrane domain, and cytoplasmic domain. During virus entry, S1 binds to a receptor on the hosT-cell surface for viral attachment, and S2 fuses the host and viral membranes, allowing viral genomes to enter hosT-cells.

Previous studies suggest that protein antigenicity is generally determined by its specified epitopes instead of the full length sequence [27]. To identify the antigen epitopes, bioinformatics methods are used to predict their sequences. Predicted epitopes are further synthesized in vitro and validated with experiments. DNAStar, BepiPred 1.0 server, and COBEP were used to identify the potential antigen epitope regions of protein (Table 2). The final B-cell epitopes of S protein included 22 sequences through combining the results of the three tools. The S1 and S2 of spike protein has 16 and 6 B-cell epitopes, respectively. These peptides were also shown in the primary and tertiary structure of the S1 and S2 of spike protein (Figure 2). The residues of B-cell epitopes were summarized and extracted in the Table 7.

E protein

The E protein is the smallest of the major structural proteins in CoV which was identified as the structural component of the virus. The E protein massively expressed virus envelope protein and plays an important role in virus membrane packaging [28]. The tertiary structure structure reveals that E protein of 2019-nCoV is a pentamer and contains multiple short α-helix (Figure 3B). Amphipathic α-helix oligomerizes to form an ion-conductive pore in membranes [29]. BepiPred 1.0 server and COBEP were used to identify the potential antigen epitope regions of protein (Table 4). Two B-cell epitopes in each monomer of E protein was identified through combining the two results of bioinformatic tools. The epitopes were also shown in the primary and tertiary structure of the E protein (Figure 3). Two epitopes are located at the head and tail of the monomer of E protein and are regularly arranged at the lower and outer sides of the pentamer (Figure 3C and 3D). The residues of B-cell epitopes were summarized and extracted (Table 7).

M protein

The M protein is the central organiser of CoV assembly and the most abundant structural protein , interacting with all other major coronaviral structural proteins [30]. [31]. Homotypic interactions between the M proteins are the major driving force behind virion envelope formation and defines the shape of the viral envelope [32]. The M protein composed of a long α-helices and three β-sheets (Figure 4). BepiPred 1.0 server and COBEP were used to identify the potential antigen epitope regions of protein (Table 5). Through integrating the results from bioinformatic tools, the final 2 potential B-cell epitopes were determined. The epitopes were also shown in the primary and tertiary structure of the M protein (Figure 4). Two epitopes are located at C-terminus of the M protein (Figure 4). The residues of B-cell epitopes were summarized and extracted (Table 7).

N protein

Among structural proteins, N protein is the only protein that functions primarily to bind to the CoV RNA genome. The nucleocapsid is formed by the association of nucleocapsid (N) protein with single-stranded viral RNA，The N protein, which binds to the genomic RNA via a leader sequence, recognises a stretch of RNA that serves as a packaging signal and leads to the formation of the helical ribonucleoprotein (RNP) complex during assembly making up the nucleocapsid [33]. The domains are named at N-terminal ends (NTD) and C-terminal ends (CTD) (Figure 5B). The two domains of the N protein were constructed by homology modeling (Figure 5C and 5D ). The CTD forms a tightly intertwined dimer, indicating that the basic building block for coronavirus nucleocapsid formation is a dimeric assembly of N protein [34]. The N protein is a highly immunogenic phosphoprotein also implicated in viral genome replication [34]. DNAStar, BepiPred 1.0 server, and COBEP were used to identify the potential antigen epitope regions of protein (Table 6). The final 7 potential B-cell epitopes were determined through integrating the results from bioinformatic tools. The epitopes were also shown in the primary and tertiary structure of the N protein (Figure 5). The NTD and CTD has 3 and 4 B-cell epitopes, respectively (Figure 5C and 5D ). The residues of B-cell epitopes were summarized and extracted (Table 7).

In short, the structure and immunogenicity of 2019-nCoV structural protein were analyzed by bioinformatics tools. Thirty-three B-cell epitopes of four structural proteins were determined in which include S protein (22), N protein (7), M protein (2), and E protein (2), respectively (Figure 6A). The B-cell epitopes residues of four structural proteins were summarized and extracted (Table 7). The proportion of epitope residues in primary sequence was calculated. The proportion of epitope residues in primary sequence was used to determine the antigenicity of proteins. The E protein has the largest antigenicity in which residue coverage of B-cell epitopes is 24% (Figure 6B). The E protein might be the potential targets to design effective 2019-nCoV vaccines and facilitate the development of rapid diagnostic methods in the future.

3.3. T-cell epitopes prediction of structural protein

T-cell immune response plays a very important role in persistent viral infection [35]. Cellular immune response impact disease progression and is essential factor for the viral clearance from the patients. T-cells immune response usually has been observed within 4–5 days after after a viral infection [36]. Antigenic peptides of the coronavirus protein can be recognised by T-cells on the surface of infected cells [37]. The structure of the MHC-I molecule HLAA*1101 in complex with such a peptide derived from the SARS-CoV protein has recently been determined [38]. T-cell epitope prediction is for identifying the shortest peptides of allergen that bind to the MHC complexes. T-cell epitopes are principally predicted on the basis of identifying the binding of amino acid fragments to the MHC complexes that can activate T-cells.

The binding strength of each peptide to the given MHC is estimated by NetMHCII 2.2 at a set threshold level. Given the MHC alleles have tens of thousands of kinds, in order to ensure the representative and reliability prediction results, we selected the most common MHC in the population to predict their peptide binding activity with protein, including HLA-DR, HLA-DQ, and HLA-DP. The predicted results of the four structural proteins are listed in Table 3-6. The number of MHC-binding peptides of the four structural proteins predicted by different alleles is counted in Table 8. The peptide will possess stronger immunogenicity in case it binds more alleles. The number of MHC-binding peptides of different allele coverage is counted in Table 9. The final T-cell epitopes was determined through the allele coverage of more than 70%. The final T-cell epitopes included 39 sequences through combining the results of the three alleles, in which include spike protein (25), nucleocapsid protein (6), membrane protein (7), and envelope protein (1), respectively (Figure 6A). The residues of T-cell epitopes were summarized and extracted (Table 10). The proportion of epitope residues in primary sequence was calculated (Figure 6B). The proportion of epitope residues in primary sequence was used to determine immunogenicity of proteins. The membrane protein has the largest immunogenicity in which residue coverage of T-cell epitopes is 55.86% (Figure 6B). The reason that immune storm was caused by 2019-nCoV maybe that the membrane and envelope protein expressed plentifully in cell infected. The knowledge of antigenic or epitopic sites of viral protein is important for the development of effective antiviral inhibitors or vaccine. For effective vaccine, both T- and B-cells epitopes identification is very important for prevention or clearance of infection [39].

These results indicate the importance of this region for the development of effective vaccine. Identified B-cell epitope can be utilized in the development of the effective 2019-nCoV vaccine because it is a vital step for development of epitope-based vaccines and diagnostic tools. Understanding the structural protein structure and function could possibly find therapeutic targets to prevent and control the coronaviruses related diseases. Therefore M protein and E protein was chosen as a potential antigenic target for the humoral immune responses, which might be significant for developing better diagnostic and research reagents in the future. Thus our study suggests that E protein could possibly be a good candidate for B cell-line epitopes in preparing monoclonal antibodies, vaccines and anti-viral inhibitors against CoV infection in the future.

In the present study, using bioinformatics methods, we analyzed the four structural proteins of 2019-nCoV and identified a potential T-cell epitope and B-cell epitope of the structural proteins, which might significantly improve our current 2019-nCoV vaccine development strategies. These predicted epitopes can be used as potential targets for the development of the effective vaccine against 2019-nCoV.

Author Contributions

Y.L. wrote the main manuscript and performed the experiments presented in Figure 1–5 and analyzed the data. M.M. performed the experiments presented in Table 1-3 and analyzed the data. Z.L., N.Z., X.S., and L.Y. designed the project, supervised the experiments and wrote the manuscript. All authors reviewed the manuscript.

Funding

This study was supported by grants from the National Natural Science Foundation of China (No. 81901684, 31729002, and U1801286), Shenzhen Scientific Technology Basic Research Projects (No.JCYJ20180306171550045).

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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Table 1. Physicochemical characterization of structural proteins of 2019-nCoV.

Proteins	ORF	Number of amino acids	Molecular weight	theoretical pI	Instability index	GRAVY	GenBank accession
S protein	ORF2 (21563..25384)	1273	141.2 kDa	6.24	33.01	-0.079	QHN73810.1
E protein	ORF4 (26245..26472)	75	8.4 kDa	8.57	38.68	1.128	QHN73812.1
M protein	ORF5 (26523..27191)	222	25.2 kDa	9.51	39.14	0.446	QHN73813.1
N protein	ORF9a (28274..29533)	419	45.6 kDa	10.07	55.09	-0.971	QHN73817.1

Table 2. The predictions results of B-cell epitopes of S protein.

Tools	Location of the prediction results
DNAStar	20-30,40-45,71-86,95-101,108-117,147-152,178-191,251-258,279-286,315-325,355-361,381-387,408-430,439-449,471-485,526-540,552-559,569-581,601-607,657-660,675-687,773-781,789-798,806-817,935-942,1080-1088, 1112-1124.
BepiPred	21-31,71-81,110-113,250-258,280-287,382-387,407-428,439-447,461-484,496-506, 526-532,551-554,567-580,601-607,636-643,656-659,675-687,700-707,772-780,789-797,805-816,936-941,1054-1059,1069-1090,1114-1122,1137-1150,1157-1171.
CBTOPE	21-32,66-77,134-147,164-167,174-181,203-215,256-274,280-286,304-325,345-356, 376-389,408-415,423-455,472-524,550-557,598-621,636-643,659-674,725-737,753-768,776-788,804-824,903-941,961-976,1022-1049,1075-1088,1098-1119,1137-1146, 1154-1178.

Table 3. The predictions results of T-cell epitopes of S protein.

Tools	Location of the prediction results
DRB1∗01:01	2–10,4–12,5–13,7–15,40–48,46–54,53–61,55–63,58–66,62–70,65–73,98–106,104–112,115–123,117–125,157–165,168–176,169–177,186–194,200–208,220–228,223–231,233–241,235–243,238–246,239–247,241–249,242–250,258–266,259–267,267–275,268–276,269–277,275–283,300–308,306–314,312–320,318–326,342–350,347–355,365–373,377–385,379–387,394–402,451–459,453–461,489–497,502–510,505–513,510–518,515–523,517–525,531–539,538–546,543–551,582–590,590–598,627–635,642–650,643–651,648–656,686–694,689–697,693–701,695–703,696–704,711–719,718–726,724–734,752–760,759–767,764–772,797–805,802–810,818–826,821–829,826–834,833–841,855–863,858–866,869–867,870–878,874–882,875–883,886–884,888–896,891–899,898–906,927–935,959–967,962–970,963–971,970–978,993–1001,994–1002,996–1004,1001–1009,1005–1013,1007–1015,1010–1018,1032–1040,1041–1049,1042–1050,1047–1055,1048–1056,1060–1068,1062–1070,1075–1083,1103–1111,1129–1137,1169–1177,1215–1223,1216–1224,1217–1225,1218–1226,1220–1228,1241–1249,1262–1270,1265–1273.
DRB3∗01:01	28–36,36–42,37–45,42–50,43–51,47–55,50–58,57–65,58–66,78–86,85–93,118–126,119–127,127–135,132–140,133–141,134–142,135–143,144–152,145–153,152–160,160–168,168–176,169–177,170–178,174–182,175–183,186–194,192–200,193–202,195–203,211–219,212–220,225–233,230–238,240–248,269–277,277–285,284–292,291–298,306–314,312–320,318–326,340–348,357–365,361–369,367–375,369–377,392–400,394–402,395–403,399–407,401–409,402–410,417–425,421–429,445–453,456–464,463–471,464–472,489–497,495–503,497–505,505–513,507–515,551–559,564–572,565–573,568–576,584–592,624–632,627–635,635–643,643–651,658–666,659–667,660–668,699–707,706–714,718–726,734–742,741–749,780–788,781,789–797,800–808,805–813,816–824,817–825,821–829,825–833,826–834,833–841,836–844,863–871,864–872,898–906,903–911,904–912,915–913,926–934,976–984,990–998,991–999,1067–1075,1081–1089,1094–1102,1095–1103,1102–1110,1114–1122,1115–1123,1148–1156,1208–1216,1220–1228,1256–1264.
DRB4∗01:01	7–15,8–16,16–24,47–55,97–105,98–106,115–123,116–124,117–125,127–135,168–176,190–198,208–216,209–217,210–218,223–231,230–238,233–241,234–242,235–243,236–244,237–245,238–246,317–325,507–515,508–516,509–517,511–519,557–565,558–566,579–587,607–615,608–616,684–692,685–693,690–698,691–699,750–758,751–759,781–789,814–822,815–823,847–855,856–864,857–865,861–869,862–870,863–871,890–898,891–899,894–902,895–903,896–904,897–905,908–916,919–917,920–928,921–929,959–967,960–968,972–980,973–981,993–1001,995–1003,996–1004,999–1007,1004–1012,1005–1013,1006–1014,1007–1015,1010–1018,1011–1019,1047–1055,1048–1056,1057–1065,1129–1137,1175–1183,1176–1184,1195–,1218–1226,1225–1233,1226–1234,1263–1271,1264–1272.
DRB5∗01:01	4–12,36–44,42–50,55–63,58–66,65–73,70–78,98–106,133–141,139–147,140–148,144–152,150–158,169–177,175–183,179–187,186–194,187–195,194–202,199–207,200–208,238–246,258–266,265–273,267–275,269–277,306–314,311–319,312–320,318–326,320–328,338–346,347–355,349–357,350–358,370–378,379–387,400–408,449–457,450–458,453–461,454–462,458–466,489–497,508–516,515–523,527–535,543–551,550–558,559–567,626–634,674–682,695–703,718–726,725–733,758–766,778–786,782–790,787–795,817–825,826–834,827–835,833–841,847–855,886–894,888–896,892–900,894–902,897–905,898–906,925–933,927–935,939–947,956–964,970–978,993–1001,994–1002,1007–1015,1011–1019,1020–1028,1032–1040,1046–1054,1065–1073,1075–1083,1094–1102,1095–1103,1103–1111,1141–1149,1208–1216,1217–1225,1264–1272.
HLA-DQA10102-DQB10502	1–9,32–40,46–54,61–69,63–71,64–72,104–112,132–140,133–141,140–148,141–149,170–178,171–179,172–180,173–181,189–197,192–200,216–224,258–266,261–269,262–270,263–271,265–273,273–281,275–283,338–346,347–355,357–365,392–400,420–428,421–429,447–455,485–493,486–494,515–523,516–524,562–570,563–571,564–572,565–573,606–614,607–615,620–628,622–630,656–664,766–774,767–775,800–808,813–821,814–822,823–831,829–837,833–841,840–848,865–873,869–877,888–896,898–906,923–931,1011–1019,1044–1052,1046–1054,1047–1055,1061–1069,1098–1106,1099–1107,1106–1114,1132–1140,1144–1152,1145–1153,1192–1200,1193–1201,1202–1210,1214–1222,1216–1224,1217–1225,1220–1228.
HLA-DQA10201-DQB10301	9–17,10–18,15–23,17–25,18–26,19–27,31–39,42–50,59–67,112–120,119–127,120–128,252–260,253–261,254–262,255–263,256–264,257–265,258–266,259–267,260–268,280–288,281–289,282–290,283–291,284–294,301–309,340–348,341–349,342–350,344–352,345–353,367–375,368–376,369–377,370–378,371–379,391–399,411–419,427–435,429–437,467–475,471–479,472–480,474–482,492–500,517–525,543–551,545–553,546–554,547–555,569–577,587–595,589–597,590–598,591–599,592–600,596–604,597–605,598–606,601–609,602–610,603–611,604–612,618–626,634–642,635–643,636–644,637–645,643–651,644–652,645–653,649–657,664–672,665–673,666–674,672–680,680–688,684–692,685–693,686–694,687–695,688–696,690–698,692–700,693–701,694–702,695–703,696–704,698–706,705–713,707–715,713–721,716–724,717–725,718–726,719–727,720–728,721–729,722–730,728–736,729–737,730–738,735–743,743–751,754–762,763–771,764–772,765–773,766–774,826–834,827–835,844–852,855–863,868–876,870–878,871–879,872–880,873–881,874–882,875–883,876–884,877–885,881–889,882–900,883–891,884–892,885–893,886–894,887–895,888–896,889–897,927–935,934–942,935–943,936–944,937–945,938–946,939–947,940–948,941–949,965–973,966–974,967–975,968–976,969–977,970–978,996–1004,997–1005,1002–1010,1008–1016,1012–1020,1017–1025,1018–1026,1019–1027,1020–1028,1021–1029,1022–1030,1026–1034,1027–1035,1062–1070,1072–1080,1074–1082,1075–1083,1076–1084,1096–1104,1114–1122,1115–1123,1116–1124,1120–1128,1121–1129,1122–1130,1169–1177,1170–1178,1218–1226,1220–1228,1227–1235,1230–1238,1235–1243,1236–1244,1237–1245,1247–1255.
HLA-DQA10501-DQB10302	7–15,10–18,42–50,43–51,58–66,59–67,63–71,64–72,88–96,104–112,114–122,115–123,157–165,158–166,169–177,170–178,172–180,217–225,218–226,219–227,236–244,237–245,255–263,256–264,257–265,258–266,259–268,260–268,263–271,264–272,283–291,301–309,328–336,340–348,344–352,345–353,346–354,367–375,368–376,379–377,390–398,391–399,429–437,472–480,488–496,506–514,508–516,513–521,515–523,516–524,517–525,518–526,519–527,546–554,547–555,590–598,591–599,592–600,593–601,604–612,606–614,618–626,619–627,620–628,635–643,636–644,645–653,646–654,663–671,664–672,665–673,666–674,667–675,668–676,684–692,686–694,687–695,688–696,689–697,690–698,693–701,694–702,695–703,706–704,707–715,716–724,717–725,718–726,719–727,720–728,730–738,735–743,754–762,755–763,756–764,765–773,766–774,767–775,799–807,800–808,821–829,822–830,840–848,853–861,854–862,855–863,860–868,868–876,870–878,871–879,872–880,873–881,874–882,875–883,878–,885–,886–894,887–895,888–896,889–897,890–898,891–899,892–900,895–903,896–904,904–912,936–944,937–945,938–946,968–976,969–977,970–978,971–979,972–980,1001–1010,1009–1017,1010–1018,1017–1025,1018–1026,1019–1027,1024–1032,1045–1053,1046–1054,1048–1056,1049–1057,1055–1063,1061–1069,1062–1070,1063–1071,1064–1072,1074–1082,1075–1083,1076–1084,1110–1118,1131–1139,1169–1177,1170–1178,1217–1225,1218–1226,1221–1229,1235–1243,1236–1244.
HLA-DQA10601-DQB10402	4–12,6–14,13–21,15–23,16–24,26–34,27–35,28–36,29–37,30–38,36–44,41–49,43–51,44–52,56–64,57–65,58–66,59–67,60–68,61–69,62–70,63–71,64–72,65–73,90–98,91–99,94–102,116–124,124–132,150–158,155–163,199–207,200–208,201–209,202–210,206–214,229–237,238–246,239–247,240–248,255–263,256–264,263–271,264–272,265–273,266–274,268–276,270–278,301–309,304–312,311–319,313–321,316–324,320–328,341–349,342–350,345–353,347–355,348–356,349–357,350–358,351–359,360–368,365–373,369–377,372–380,373–381,374–382,375–383,377–385,395–403,400–408,430–438,449–457,450–458,451–459,468–476,486–494,488–496,490–498,503–511,505–513,506–514,514–522,617–625,620–628,628–636,629–637,630–638,631–639,633–641,638–646,640–648,641–649,669–677,974–682,680–688,689–697,690–698,691–699,692–700,693–701,694–702,705–703,713–721,714–722,715–723,716–724,717–725,718–726,719–727,722–730,724–732,725–733,726–734,727–735,728–736,757–765,759–767,760–768,787–795,821–829,868–876,871–879,873–881,875–883,880–888,881–889,883–891,884–892,886–894,893–901,894–902,895–903,896–904,898–906,927–935,937–945,995–1003,1002–1010,1004–1012,1005–1013,1006–1014,1007–1015,1008–1016,1009–1017,1011–1019,1022–1030,1047–1055,1048–1056,1059–1067,1061–1069,1062–1070,1063–1071,1064–1072,1073–1081,1074–1082,1075–1083,1093–1101,1094–1102,1098–1106,1099–1107,1100–1108,1101–1109,1102–1110,1154–1162,1206–1214,1207–1215,1208–1216,1209–1217,1210–1218,1212–1220,1214–1222,1215–1223.
HLA-DPA10103-DPB10601	1–9,2–10,3–11,4–12,5–13,31–39,32–40,42–50,50–58,51–59,52–60,53–61,54–62,58–66,59–67,78–86,100–108,104–112,127–135,128–136,130–138,132–140,133–141,134–142,135–143,139–147,140–148,167–175,168–176,170–178,188–196,189–197,233–241,237–245,238–246,264–272,265–273,273–281,288–296,387–495,390–398,391–399,395–403,429–437,448–456,449–457,450–458,451–459,456–464,489–497,492–500,507–515,508–516,509–517,510–518,511–519,512–520,513–521,514–522,538–546,557–567,581–589,749–857,754–762,800–808,815–823,816–824,817–825,818–826,855–863,1046–1054,1047–1055,1060–1068,1061–1069,1062–1070,1109–1117,1132–1140,1208–1210,1209–1217,1210–1218,1211–1219,1212–1220,1213–1221,1214–1222,1215–1223,1216–1224,1220–1228,1224–1232,1225–1233,1226–1234,1227–1235,1228–1236,1229–1237,1231–1239,1232–1240,1233–1241.
HLA-DPA10201-DPB10101	2–10,4–12,40–48,41–49,42–50,48–56,51–59,52–60,53–61,54–62,55–63,58–66,59–67,78–86,102–110,110–118,112–120,133–141,138–146,139–147,140–148,152–160,167–175,168–176,169–177,170–178,186–194,188–196,189–197,193–201,200–208,233–241,235–243,237–245,238–246,262–270,269–277,302–310,312–320,340–348,341–349,342–350,369–377,392–400,449–457,450–458,453–461,505–513,508–516,509–517,510–518,511–519,512–520,556–564,557–565,558–566,559–567,577–585,579–587,581–589,719–727,725–733,797–805,814–822,815–823,816–824,817–825,818–826,820–828,821–829,822–830,833–841,853–861,854–862,870–878,893–901,915–923,962–970,996–1004,1000–1008,1059–1067,1062–1070,1107–1115,1148–1156,1195–1203,1208–1216,1209–1217,1213–1221,1214–1222,1217–1225,1220–1228,1264–1272,1265–1273.
HLA-DPA10201-DPB10501	4–12,36–44,41–49,42–50,50–58,51–59,52–60,53–61,58–66,76–84,89–97,90–98,127–135,139–147,140–148,168–176,186–194,187–195,188–196,189–197,194–202,195–203,199–207,200–208,235–243,236–244,237–245,238–246,269–277,302–310,342–350,449–457,450–458,451–459,453–461,456–464,508–516,509–517,511–519,512–520,527–535,528–536,550–558,551–559,555–563,556–564,557–565,558–566,559–567,794–802,814–822,815–823,816–824,817–825,818–826,870–878,898–906,915–923,1012–1020,1149–1157,1203–1211,1214–1222,1215–1223,1264–1272.
HLA-DPA10301-DPB10402	4–12,5–13,41–49,42–50,43–51,48–56,51–59,52–60,54–62,55–63,58–66,59–67,62–70,112–120,127–135,133–141,135–143,138–146,139–147,140–148,152–160,168–176,169–177,170–178,189–197,200–208,205–213,218–226,233–241,234–242,235–243,236–244,237–245,238–246,241–249,262–270,263–271,264–272,312–320,313–321,342–350,344–352,392–400,449–457,450–458,451–459,486–494,508–516,509–517,510–518,511–519,512–520,557–565,577–585,579–587,580–588,643–651,691–699,719–727,721–729,752–760,753–761,759–767,797–805,814–822,815–823,816–824,817–825,818–826,820–828,821–829,826–834,833–841,853–861,858–866,862–870,863–871,864–872,869–877,870–878,871–879,904–912,915–913,973–981,976–984,993–1001,996–1004,1005–1013,1006–1014,1007–1015,1057–1065,1058–1066,1060–1068,1062–1070,1214–1222,1264–1272.

Table 4. The predictions results of B-cell epitopes and T-cell epitopes of E protein.

Type	Tools	Location of the prediction results
B-cell epitope prediction	DNAStar	3-10,52-70.
	CBTOPE	3-8,52-63.
	BepiPred	2-8,47-68.
T-cell epitope prediction (HLA-DR)	DRB1∗01:01	10–18,11–19,26–34,31–39,36–44,44–52,49–57,50–58,57–65,62–70.
	DRB3∗01:01	4–12,12–20,57–65.
	DRB4∗01:01	10–18,30–38,31–39.
	DRB5∗01:01	4–12,30–38,31–39,36–44,49–57,55–63,56–64,61–69.
T-cell epitope prediction (HLA-DQ)	HLA-DQA10102-DQB10502	1–9,17–25,20–28.
	HLA-DQA10201-DQB10301	6–14,7–15,8–16,14–22,24–32,27–35,28–36,29–37,30–38,32–40,33–41,46–54.
	HLA-DQA10501-DQB10302	1–9,8–16,32–40,35–43,36–44.
	HLA-DQA10601-DQB10402	2–8,10–18,18–26,21–29,24–32,25–33,26–34,27–35,29–37,30–38,32–40,33–41,40–48,42–50,45–53,52–60,54–62,55–63,56–64, 57–65.
T-cell epitope prediction (HLA-DP)	HLA-DPA10103-DPB10601	1–9,12–20,13–21,15–23,16–24,17–25,18–26,19–27,20–28,21–29,22–30,23–31,24–32,25–33,26–34,27–35,28–36,29–37,31–39,36–44,37–45,46–54,51–59.
	HLA-DPA10201-DPB10101	4–12,26–34,30–38,44–52,45–53.
	HLA-DPA10201-DPB10501	11–19,14–22,30–38,31–39,53–61,55–63,56–64,57–65.
	HLA-DPA10301-DPB10402	10–18,11–19,12–20,26–34,31–39,32–40,33–41,39–47,44–52,55–63,57–65.

Table 5. The predictions results of B-cell epitopes and T-cell epitopes of M protein.

Type	Tools	Location of the prediction results
B-cell epitope prediction	DNAStar protean	2-18,40-45,104-117,157-176,183-194,203-217.
	CBTOPE	4-10, 171-176, 185-194.
	BepiPred	1-8,112-113, 169-176,185-194,206-215.
T-cell epitope prediction (HLA-DR)	DRB1∗01:01	14–22,15–23,16–24,20–28,32–40,33–41,35–43,43–51,53–61,54–62,55–63,64–72,65–73,73–81,75–83,79–87,80–88,93–101,94–102,95–103,100–108,112–120,117–125,118–126,121–129,126–134,127–135,136–144,142–150,148–156,149–157,168–176,173–181,178–186,179–187.
	DRB3∗01:01	8–13,16–24,37–45,38–46,65–73,71–79,92–100,94–102,95–103,96–104,101–109,110–118,112–120,160–168,170–178,179–187,186–194,187–195,198–206,204–212,212–220.
	DRB4∗01:01	5–13,12–20,13–21,14–22,15–23,24–32,32–40,43–51,44–52,45–53,48–56,49–57,50–58,79–87,100–108,116–124,117–125,125–133,126–134,131–139,132–140,136–144,141–149,147–155,148–156.
	DRB5∗01:01	7–12,20–28,33–41,34–42,35–43,36–44,37–45,42–50,47–55,54–62,64–72,65–73,93–101,94–102,95–103,97–105,99–107,100–108,101–109,103–111,138–146,142–150,147–155,148–156,168–176,172–180,178–186,179–187,192–200,193–201,197–205,198–206.
T-cell epitope prediction (HLA-DQ)	HLA-DQA10102-DQB10502	16–24,17–25,33–41,34–42,35–43,36–44,41–49,43–51,52–60,53–61,54–62,55–63,65–73,89–97,91–99,92–100,96–104.
	HLA-DQA10201-DQB10301	1–9,2–10,3–11,4–12,60–68,61–69,64–72,73–81,74–82,75–83,76–84,77–85,80–88,81–89,86–94,96–104,122–130,138–146,139–147,168–175,169–177,170–178,171–179,180–188,181–189,187–195,188–196,210–218,211–219.
	HLA-DQA10501-DQB10302	4–12,30–38,57–65,58–66,60–68,63–71,64–72,75–83,76–84,77–85,78–86,79–87,80–88,124–132,213–221.
	HLA-DQA10601-DQB10402	6–14,25–33,26–34,28–36,31–39,37–45,44–52,45–53,47–55,52–60,53–61,55–63,56–64,60–68,62–70,63–71,64–72,65–73,66–74,69–77,73–81,75–83,84–92,90–98,92–100,93–101,94–102,95–103,96–104,97–105,98–106,99–107,100–108,101–109,102–110,103–111,104–112,108–116,120–128,126–134,127–135,138–146,142–150,143–151,149–157,166–174,167–175,168–176,169–177,172–180,173–181,174–182,177–185,178–186,191–199,193–201,194–202.
T-cell epitope prediction (HLA-DP)	HLA-DPA10103-DPB10601	19–27,20–28,21–29,22–30,23–31,24–32,25–33,26–34,27–35,28–36,29–37,30–38,31–39,32–40,34–42,43–51,44–52,45–53,46–54,47–55,48–56,49–57,50–58,51–59,52–60,53–61,54–62,55–63,57–65,60–68,61–69,62–70,63–71,64–72,65–73,66–74,70–78,82–90,84–92,85–93,86–94,87–95,88–96,89–97,90–98,91–99,92–100,93–101,94–102,95–103,128–136,138–146.
	HLA-DPA10201-DPB10101	5–13,7–15,14–22,15–23,21–29,28–36,31–39,34–42,42–50,43–51,44–52,53–62,54–62,55–63,64–74,65–73,89–97,90–98,92–100,93–101,94–102,95–103,96–104,97–105,99–107,112–120,117–125,123–131,127–135,130–138,131–139,132–140,173–181,193–201.
	HLA-DPA10201-DPB10501	7–15,8–14,14–22,15–23,28–36,34–42,37–45,41–49,42–50,43–51,44–52,54–62,55–63,62–70,64–72,65–73,89–97,90–98,91–99,93–101,94–102,95–103,96–104,97–105,99–107,100–108,101–109,117–125,132–140,138–146,142–150,143–151,144–152,173–181,193–201,199–207.
	HLA-DPA10301-DPB10402	8–16,15–23,16–24,21–29,26–34,27–35,28–36,34–42,42–50,53–61,55–63,65–73,86–94,89–97,90–98,92–100,94–102,95–103,96–104,97–105,112–120,117–125,118–126,126–134,127–135,128–136,131–139,132–140,137–145,143–151,144–152,148–156,168–176,193–201.

Table 6. The predictions results of B-cell epitopes and T-cell epitopes of N protein.

Type	Tools	Location of the prediction results
B-cell epitope prediction	DNAStar	5-12,19-48,59-70,78-84,90-106,114-120,122-130,139-152,162--215,227-264,274-300,323-329,334-349,357-389,400-405,414-418.
	CBTOPE	1-8,23-30,43-46,54-56,70-73,79-86,100-111,145-147,164-178, 230-244, 266-300,310-327,355-383,404-410.
	BepiPred	1-51,58-85,93-104,115-127,137-154,164-216,232-269,273-287,291-301,306-310,323-331,338-347,361-387.
T-cell epitope prediction (HLA-DR)	DRB1∗01:01	52–60,53–61,110–118,111–119,130–138,132–140,157–165,159–167,165–173,215–223,219–227,222–230,227–235,314–322,330–338,331–339,349–357,351–359,360–368,392–400.
	DRB3∗01:01	86–94,100–108,125–133,213–221,221–229,222–230,266–274, 306–314,307–315,345–353,351–359,355–363,374–382.
	DRB4∗01:01	130–138,153–161,154–162,155–163,156–164,157–165,217–225,218–226,219–227,220–228,221–229,222–230,303–311,348–352,349–357,350–358,351–359,392–400.
	DRB5∗01:01	6–14,28–36,32–40,52–60,53–61,85–93,86–94,87–95,94–102, 110–118,157–165,171–179,177–185,181–189,183–191,187–195,249–257,253–261,254–262,258–266,268–276,291–299,292–300,307–315,311–319,314–322,330–338,331–339,349–357,353–361,379–387,392–400.
T-cell epitope prediction (HLA-DQ)	HLA-DQA10102-DQB10502	56–64,83–91,107–115,108–116,152–160,153–161,217–225,218–226,219–227,223–231,282–290,286–294,303–311,333–341,351–359,352–360,353–361,393–401,394–402,395–403.
	HLA-DQA10201-DQB10301	15–23,47–55,48–56,49–57,50–58,112–120,113–121,131–139, 132–140,133–141,134–142,152–160,174–182,176–184,180–188,182–190,197–205,198–207,199–207.200–208,201–209,202–210,203–211,210–218,211–219,212–220,244–252,245–253,246–254,247–255,263–271,303–311,304–312,305–313,307–315,308–316,309–317,310–318,323–331,324–332,325–333,330–338,331–339,332–340,389–397,390–398,391–399,406–414,408–416,409–417,410–418,411–419.
	HLA-DQA10501-DQB10302	49–57,50–58,51–59,110–118,111–119,129–137,130–138,151–159,154–162,203–211,213–221,214–222,217–225,300–308,301–309,304–312,305–313,306–314,307–315,308–316,309–317,310–318,313–321,314–322,315–323,317–325,318–326,324–332,332–340,333–341,388–396,389–397,390–398,391–399,392–400,393–401,394–402,407–415,408–416.
	HLA-DQA10601-DQB10402	48–56,49–57,50–58,51–59,52–60,53–61,54–62,83–91,84–92,85–93,86–94,87–95,106–114,108–116,111–119,130–138,169–177, 244–252,263–271,268–276,269–277,298–306,305–313,311–319,313–321,314–322,322–330,327–335,328–336,329–337,330–338,331–339,390–398.
T-cell epitope prediction (HLA-DP)	HLA-DPA10103-DPB10601	107–115,108–116,109–117,110–118,217–225,218–226,219–227.
	HLA-DPA10201-DPB10101	49–57,50–58,105–113,155–163,216–224,217–225,218–226,219–227,220–228,221–229,222–230,345–353,346–354,387–395.
	HLA-DPA10201-DPB10501	105–113,106–114,218–226,219–227,220–228,221–229,311–319, 330–338,331–339,346–354,349–357,387–395.
	HLA-DPA10301-DPB10402	49–57,218–226,219–227,220–228,221–229,222–230,317–325, 331–339,387–395.

Table 7. Predicted B-cell epitopes of 2019-nCoV structural proteins.

Protein	Code	Position	Sequence
S protein	B1	21-30	RTQLPPAYTN
	B2	71-77	SGTNGTK
	B3	110-113	LDSK
	B4	251-258	PGDSSSGW
	B5	280-286	GTITD
	B6	315-325	TSNFRVQPTES
	B7	382-387	VSPTKL
	B8	408-415	RQIAPGQT
	B9	439-447	NNLDSKVGG
	B10	471-484	EIYQAGSTPCNGVE
	B11	526-532	GPKKSTN
	B12	551-557	VLTESNK
	B13	601-607	GTNTSNQ
	B14	636-643	YSTGSNVF
	B15	656-659	VNNS
	B16	675-687	QTQTNSPRRARSV
	B17	773-780	EQDKNTQE
	B18	789-797	YKTPPIKDF
	B19	805-816	ILPDPSKPSKRS
	B20	936-941	DSLSST
	B21	1080-1088	AICHDGKAH
	B22	1114-1122	IITTDNTFV
N protein	B1	43-46	QGLP
	B2	100-104	KMKDL
	B3	164-178	GTTLPKGFYAEGSRG
	B4	275-283	GRRGPEQTQ
	B5	296-300	TDYKH
	B6	323-329	EVTPSGT
	B7	361-365	KTFPP
M protein	B1	171-176	ATSRTL
M protein	B2	185-194	QRVAGDSGFA
E protein	B1	3-8	SFVSEE
E protein	B2	52-63	VKPSFYVYSRVK

Table 8. The number of MHC-binding peptides of different alleles prediction

Type	Tools	S protein	N protein	M protein	E protein
T-cell epitope prediction (HLA-DR)	DRB1∗01:01	119	20	35	10
	DRB3∗01:01	114	13	21	3
	DRB4∗01:01	84	18	25	3
	DRB5∗01:01	91	32	32	8
T-cell epitope prediction (HLA-DQ)	HLA-DQA10102- DQB10502	77	20	17	3
	HLA-DQA10201- DQB10301	182	52	29	12
	HLA-DQA10501- DQB10302	162	39	15	5
	HLA-DQA10601- DQB10402	174	33	57	20
T-cell epitope prediction (HLA-DP)	HLA-DPA10103- DPB10601	96	7	52	23
	HLA-DPA10201- DPB10101	93	14	34	5
	HLA-DPA10201- DPB10501	64	12	36	8
	HLA-DPA10301- DPB10402	96	9	34	11

Table 9. The number of MHC-binding peptides of different allele coverage

Allele coverage	S protein			N protein			M protein			E protein
	DR	DQ	DP	DR	DQ	DP	DR	DQ	DP	DR	DQ	DP
100%	0	0	18	0	0	2	0	0	5	0	0	0
75%	17	24	20	5	4	3	6	1	18	1	1	2
50%	62	113	44	11	29	6	23	17	18	6	7	6
25%	234	294	129	46	74	13	49	81	46	9	23	29

Table 10. Predicted T-cell epitopes of 2019-nCoV structural protein.

Protein	Code	Position	Sequence
S protein	T1	4-12	FLVLLPLVSS
	T2	41-76	KVFRSSVLHSTQDLFLPFFSNVTWFHAIHVSGTNGT
	T3	98-106	SNIIRGWIF
	T4	127-148	VIKVCEFQFCNDPFLGVYYHKN
	T5	168-178	FEYVSQPFLMD
	T6	186-197	FKNLREFVFKNI
	T7	233-246	INITRFQTLLALHR
	T8	255-277	SSGWTAGAAAYYVGYLQPRTFLL
	T9	301-326	CTLKSFTVEKGIYQTSNFRVQPTESI
	T10	342-353	FNATRFASVYAW
	T11	449-458	YNYLYRLFRK
	T12	489-497	YFPLQSYGF
	T13	508-520	YRVVVLSFELLHA
	T14	557-565	KKFLPFQQF
	T15	620-628	VPVAIHADQ
	T16	693-702	IAYTMSLGAE
	T17	716-727	TNFTISVTTEIL
	T18	766-774	ALTGIAVEQ
	T19	814-841	KRSFIEDLLFNKVTLADAGFIKQYGDCL
	T20	871-906	AQYTSALLAGTITSGWTFGAGAALQIPFAMQMAYRF
	T21	915-923	VLYENQKLI
	T22	993-1001	IDRLITGRL
	T23	1007-1015	YVTQQLIRA
	T24	1062-1083	FLHVTYVPAQEKNFTTAPAICH
	T25	1214-1222	WYIWLGFIA
N protein	T1	49-58	TASWFTALTQ
	T2	157-165	IVLQLPQGT
	T3	218-230	ALALLLLDRLNQL
	T4	305-313	AQFAPSA
	T5	351-359	ILLNKHIDA
	T6	387-400	KKQQTVTLLPAADL
M protein	T1	15-73	KLLEQWNLVIGFLFLTWICLLQFAYANRNRFLYIIKLIFLWLLWPVTLACFVLAAVYRI
	T2	89-108	GLMWLSYFIASFRLFARTRS
	T3	117-125	NILLNVPLH
	T4	132-140	PLLESELVI
	T5	148-156	HLRIAGHHL
	T6	179-187	YKLGASQRV
	T7	193-201	FAAYSRYRI
E protein	T1	26-40	FLLVTLAILTALRLC

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Structure/epitope-based immunoinformatics analysis of structural proteins of 2019 novel coronavirus

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