Recently our attention has been focused on the spread of coronavirus that occurs in the world without exception in Indonesia. The case spread is dramatically increasing in a short period of time. Starting from the outbreak case that occurred in Wuhan, China then quickly spread to other countries, and finally in March 2020 confirmed coronavirus cases occurred in Indonesia.
Coronavirus is a large family of viruses that can cause disease with mild to severe symptoms. Some examples of coronaviruses that can cause severe symptoms are Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). Coronavirus Disease 2019 (COVID 19) is a new type of disease that has never been identified previously caused by a virus called SARS-CoV-2. This virus is a zoonotic virus, which means transmitted between animals and humans. A common symptom of someone infected with COVID-19 is the presence of acute respiratory disorders such as fever, coughing, and shortness of breath. In severe cases, it can cause pneumonia, acute respiratory syndrome, kidney failure, and even death. Reported clinical signs and symptoms related to sufferers of this disease are fever, difficulty breathing and the presence of extensive infiltrate pneumonia in both lungs on patient’s x-ray results (DJPPP Ministry of Health, 2020).
WHO determined that COVID-19 has become a global pandemic on April 2020, according to data there are positive COVID-19 cases totaling 1,524,161 cases, and cases of death from COVID-19 totaling 92,941 cases, this cased are from 213 countries who have infected by COVID-19 (WHO, 2020). The prevalence of COVID-19 cases in Indonesia until 9 June 2020, Government has confirmed 32.076 positive cases from 34 provinces in Indonesia with 1.923 death cases (Ministry of Health 2020).
Researchers are trying hard to find a drug that can be used to treat this disease. Researchers have revealed that more than 30 agents including western medicine, natural products, and Chinese medicine have the potential against COVID-19. However, until now there is no definite and recommended therapy/drug for COVID-19 because this is a new disease. Current treatment is the administration of drugs or curative therapy using antivirals, this was chosen because COVID-19 is a disease caused by a viral infection. Antiviral therapy refers to therapies used when MERS and SARS pandemics such as interferon α (IFN-α), lopinavir/ritonavir, chloroquine phosphate, ribavirin, and arbidol have been included in the latest version of the Guidelines for the Prevention, Diagnosis, and Treatment of Novel Coronavirus-induces Pneumonia issued by the Republic of China National Health Commission (NHC) for tentative treatment in handling COVID-19 (Dong et al, 2020). In addition to the use of antiviral therapy, antibiotic therapy such as amoxicillin, azithromycin, or fluoroquinolones is used (Jin et al, 2020).
The mechanism of this virus infection is virus enters the cell and reproduces itself using a host cell machine together with the damage to the host cell, this is the key to finding and developing a therapy for COVID-19 in the future. The SARS-CoV-2 virus induces the respiratory system and alveoli cells in the lungs are stem cells infected by this virus (Chhikara et al, 2020)
In patients with mild manifestations of COVID-19, there was no increase in chemokine and proinflammatory cytokines even in patients who showed symptoms. Whereas in the case of COVID-19 with severe symptoms, a lower lymphocyte count, leukocytes, and a higher neutrophil-lymphocyte ratio and a lower percentage of monocytes, eosinophils and basophils were obtained. Proinflammatory cytokines such as TNF-α, IL-6, and IL-8 and infection markers such as procalcitonin, ferritin, and C-reactive protein are also found to be higher in cases with severe clinical symptoms. The main cause of death in patients with COVID-19 is caused by ARDS (Acute Respiratory Distress Syndrome). This occurs because of a cytokine storm, which is an uncontrolled systemic inflammatory response due to the release of large amounts of proinflammatory cytokines (IFN-α, IFN-β, IL-1β, IL-2, IL-6, IL-7, IL-10, IL-12, IL-18, IL-33, TNF-α, and TGF-β) and large amounts of chemokines. This excessive immune response can cause lung damage and fibrosis thich lead to functional disability (Susilo et al, 2020).
Along with the development of technology, stem cell-based biological medical therapy, and stem cell-based immunotherapy were developed to find out its potential in the case of COVID-19 treatment besides using chemical drugs as a therapy.
Hematopoietic stem cells (HSC) are multipotent progenitor cells that can renew themselves from all different types of blood cells appear during the process of hematopoiesis. One of the important features of HSC is the ability to do self-renew, which is making copies with the same or very similar potential. The blood and the system that forms it, known as the hematopoietic system, consist of many types of cells with special functions (Domen et al., 2006).
Sources of hematopoietic stem cells are from PBMC, Bone marrow, and umbilical cord blood cells. The following are the SPH isolation and culture protocols derived from PBMCs and bone marrow stem cells which must express CD105, CD73, and CD90 and less express CD45, CD34, CD14
The mechanism of the immunomodulatory effects of HSCs is not yet fully understood, although direct and indirect effects have been demonstrated through cell-to-cell interactions or dissolved factors that create a local immunosuppressive environment. HSCs alter the cytokine secretion profile of dendritic cells, naive and effector T cells, and NK cells to induce a more anti-inflammatory and tolerant phenotype. The secretion of proinflammatory cytokines, TNF-α and IFN-γ decreases while IL-4 and IL-10 are more suppressive stimulated. Other factors involved include hepatocyte growth factor, TGF-β1, IL-10, IL-6, prostaglandin E2, nitric oxide, and possible indoleamine 2,3-dioxygenase. Although the exact mechanism has not been clarified yet, some evidence suggests that HSCs are immunosuppressive and anti-inflammatory and can be grafted between incompatible individuals
Based on the above background, an in vitro study was conducted regarding the potential hematopoietic stem cells (HSC) against SARS-CoV-2 (COVID-19) viruses with virus isolates from Indonesia.