Stem Cell Therapy: A Possible Solution for Coronavirus
- 1. American Stem Cell Base, Los Angeles, CA, USA
- 2. Stem Cell Life Science Corporation, New Taipei City, Taiwan
- 3. Loma Linda University School of Medicine, Loma Linda, CA, USA
- 4. LifeCode Biotech Company, Taipei, Taiwan
Abstract
Coronavirus (Covid-19) has caused a global pandemic. Consequently, companies have manufactured vaccines to combat the spread of Covid-19 and protect those who become vaccinated. However, the current vaccines do not seem to be effective against the new variants of the virus that have emerged. Stem cell therapy could be an alternative. The immunomodulatory effects from stem cell therapy can inhibit the immune system overactivation therefore lower the mortality rate by preventing or attenuating the cytokine storm caused by Covid-19. It can reduce time to recovery with its regenerative effects by repairing damages caused by Covid-19 and improving bodily functions. In addition, unlike most traditional medicine, no adverse effects have been observed after treatment. All this suggests that stem cell therapy is a promising and viable solution to combat and treat Covid-19.
Citation
Wang FN, Hsu MC, Wang SL, Wang SG, Chen WC, et al. (2021) Stem Cell Therapy: A Possible Solution for Coronavirus. J Hematol Transfus 8(2): 1094.
INTRODUCTION
Coronavirus (Covid-19) is a contagious and infectious disease that was first reported from Wuhan, China. It is caused by acute respiratory syndrome coronavirus 2 (SARS-CoV-2), an enveloped ribonucleic acid (RNA) virus [1,2]. Unlike deoxyribonucleic acid (DNA) viruses, RNA viruses are more difficult to develop vaccines for as they have the ability to adapt to their hosts and are prone to mutations resulting in many different variants. As a result, RNA vaccines are difficult to develop and/or rarely used [3,4]. SARS-CoV-2 causes patients to have complex and varied systemic symptoms including acute respiratory distress syndrome (ARDS), pulmonary fibrosis, and multiple organ failure. The onset symptoms of the coronavirus often come quickly and vary from mild symptoms to severe illness [5]. The World Health Organization (WHO) has declared a global pandemic as Covid-19 has spread throughout the world causing over 2.9 million deaths [1]. It resulted in pharmaceutical companies and research labs worldwide to accelerate research for the development of a Covid-19 vaccine.
Current Covid-19 vaccines have many side effects with the most common side effects including fever, chills, fatigue, headache, body aches, nausea, diarrhea, and pain and swelling at the site of injection. It takes more than two months for the antibodies to fully develop. During this time people can still get infected with SARS-CoV-2 [6]. The SARS-CoV-2 vaccines such as BNT162b2 vaccine, mRNA-1273 vaccine, Ad26.COV2.S, etc are only effective against certain SARS-CoV-2 strains [7-9]. They have an efficiency rate up to 94.1% [8]. After the vaccination, people become immune to some strains of coronavirus. Unfortunately, multiple new variants of SARS-COV-2 have emerged [10]. The current vaccines are not effective against these new variants.
While the efficiency rate of the Covid-19 vaccine is high, the emergence of the new Covid-19 variants brings up the problem and question; what could be a possible solution? A solution to this problem lies in stem cell therapy.
Stem Cell Therapy
Stem cells therapy is a potential noninvasive method for treating the emerging variants ofSARS-COV-2 that the coronavirus vaccine is ineffective against. When an oocyte is fertilized by a sperm, it develops into a blastocyst. The blastocyst’s inner cell mass (ICM) is the most primitive source of embryonic stem cells [11-13]. Embryonic stem cells can also be derived from fetal gonadal tissue [12]. Stem cells can be totipotent, pluripotent, multipotent, oligopotent, and unipotent. They are unspecialized cells that have self-renewing ability and the ability to differentiate into cells with specialized functions [13]. In just a few months, stem cells can differentiate into more than two hundred kinds of cells in the human body. These cells have specialized functions that are responsible for various physiological mechanisms in the human body [14]. The ability to differentiate into different types of cells gives stem cells the potential to be used for therapeutic uses. Stem cells are easily obtained and can be effectively isolated from amniotic fluid, umbilical cord, the placenta, dental pulp, olfactory tissues, etc and cultured in vitro for clinical use [15,16]. Once isolated, the application of intravenous infusion of stem cells works quickly and effectively with the dual functions of prevention and treatment [15]. Stem cell therapy has shown promise for treating; pulmonary fibrosis [17], plaque psoriasis [15], liver disease [18], strokes [19], heart disease [20], etc. They have antibacterial, anti-apoptotic, immunomodulatory, and regenerative effects [16,21-25]. These effects have the potential to treat many diseases including Covid-19.
In a randomized control trial, mesenchymal stem cells (MSC) were intravenously injected to treat H7N9, a virus that induced ARD and other symptoms similar to Covid-19. After treatment, the survival rate was 84.2% for those that underwent stem cell therapy compared to 53.5% from the control group. These researchers also found that MSC have anti-inflammatory effects, and the ability to defend against a cytokine storm. In addition after a five-year follow-up, it was observed that stem cell therapy did not result in any adverse effects [26]. This study foreshadowed the potential for stem cell therapy as a possible therapeutic route for treating Covid-19.
A case report on a 65-year-old woman with severe Covid-19 symptoms showed that treatments with human umbilical cord MSC resulted in the patient recovering from Covid-19 with negative throat swab Covid-19 tests four days later [27]. When critically ill patients with Covid-19 were treated with stem cells, it was observed that the stem cells modulated the immune system and increased the survival rates up to 71.4% compared to only 28.6% from the control group [22]. A double-blind randomized control trial also found that MSC treatments were safe as they did not cause serious adverse effects, significantly decreased the number of inflammatory cytokines involved with the cytokine storm, decreased time to recovery, and improved the patient survival compared to the controls [28]. Similar to the previous finding, another clinical trial with seven patients with severe Covid-19 were treated with MSC and assessed 14 days after treatment. After two days pulmonary functions had improved. At the end of the trial, all seven patients were either cured or had significantly improved functional outcomes in their inflammatory and immune function levels. Again, no adverse effects were observed. It was also found that Covid-19 was unable to infect the stem cells and concluded that stem cell therapy is a safe and effective treatment to treat Covid-19 patients [29]. In another single-center randomized controlled trial, patients with severe Covid-19 were treated with intravenous MSC treatment. Compared to the control group, patients treated with stem cells had faster recovery with improvements to weakness and fatigue, shortness of breath, low oxygen saturation, and returned to a normal range for lymphocyte count. A significant difference in recovery was observed by day 7. No mortalities occurred in the treatment group (n=12), but unfortunately, four patients from the control group (n=19) passed away [30]. Based on these research studies, it can be concluded that stem cell therapy should be a priority treatment for Covid-19.
DISCUSSION
Covid-19 has a spectrum of symptoms, from asymptomatic to severe conditions that could lead to septic shock, multiple organ dysfunction, or death. It can also cause patients to have severe and rapid inflammation and substantial reduction of immunity. Covid-19 causes cytokine-storms that produce a number of inflammatory factors. If the cytokine-storms are not treated, it can result in death [16,31]. All these symptoms are within the scope of potential therapeutic uses for stem cells. With the aid of the vaccination along with stem cell therapy, people are less likely to get infected or have milder symptoms and less organ damages as damage caused by the Covid-19 can be repaired. The antiapoptotic effects of stem cells could potentially help Covid-19 patients by preventing cell death of resident and immune cells, while the antibacterial effects could mitigate secondary bacterial and fungal infections that may develop in patients [25]. Since stem cells have the ability to control effective factors and differentiate into tissues for regeneration of the injured cells caused by Covid-19, stem cell therapy can play an essential role to help patients recover from their damaged organs. Therefore, in theory, and as proven in the above-mentioned studies, Covid-19 can potentially be treated by stem cell therapy as stem cells can greatly improve the symptoms of patients with mild, moderate, and severe coronavirus infections, and repair the damage caused by Covid-19.
Despite overwhelming evidence that stem cell therapy has an incredible amount of potential, a weakness of current studies is the small sample size. However, this is also a strength because it shows that stem cell therapy is beneficial therefore paves the way for future studies. Unfortunately, there are challenges to overcome. One of the challenges faced is: conducting clinical trials and attaining a larger sample size and the ethics behind experimental therapy on humans. On top of that, another challenge is that there are no current Food and Drug Administration (FDA) approved stem cell therapies for the prevention and treatment of Covid-19 [32]. However, as a result of the pandemic, the FDA has created an emergency program called the Coronavirus Treatment Acceleration Program (CTAP) allowing emergency use authorizations (EUAs) of stem cells [33]. The future directions should be focused on getting an FDA approved stem cell therapy. If approved, stem cell therapy can be a possible therapeutic solution to combat coronavirus.
REFERENCES
6. CDCgov. Possible Side Effects After Getting a COVID-19 Vaccine | CDC. 2021; 36: 20Z.
14. Home | STEM Cell Information.
31. Hu B, Huang S, Yin L. The cytokine storm and COVID-19. J Med Virol. 2021; 93: 250-256.
32. Cell-Based Therapy | COVID-19 Treatment Guidelines. NIHCOVIDTx Guide. 2021.
33. US_FDA. Coronavirus Treatment Acceleration Program (CTAP) | FDA. 2021.
