The statistics of recovered patients in the world are slowly rising. Across the world, we have about a 25% recovery rate. Even though that is still far beyond our target which is 100%, we should still be optimistic about the efforts of our scientists and medical experts. While there is still no specific treatment that has proven effective to cure this disease, you may have heard of some promising treatments for COVID-19. This puts the attention of many now on convalescent plasma and why it has been used in clinical trials as of late.  

Plasma For Immunity

Blood is made up of different types of cells. There are red blood cells that carry your oxygen and wastes in and out of our bodies. White blood cells that are responsible for our immunity. We also have platelets that are involved in the prevention of bleeding. When these cellular particles are separated, what is left is plasma. This contains different substances like proteins, salts, enzymes, water, and antibodies.

Antibodies, also known as immunoglobulins, are proteins that are produced by the immune system. Their primary function is to attack a foreign invader, like a virus or bacteria. Upon the arrival of the virus or bacteria (antigens) in the body, antibodies are produced to basically attack it. 

There are three different roles of antibodies:

• They circulate the antigen to contain it
• They bind to, attack, and kill the antigen
• They attach to the antigen and prevent it from infecting other cells

These antibodies can identify an antigen that has previously attacked the system. By collaborating with other cells, they can remember the characteristics of their enemy and become activated into defense mode.

Therefore, if your immune system encounters the COVID-19 virus, your immune system can now provide immunity for you against the virus.

Donating Antibodies

A surprising number of COVID-19 survivors have expressed the desire to donate their blood. To do so, laboratories can now extract the plasma with antibodies that were already trained to combat the coronavirus. The antibodies will now be fighting the same antigen, however, within a different individual.

This blood component with these activated antibodies is called convalescent plasma. This plasma from recovered COVID-19 positive patients is properly selected and screened. Their ABO grouping, as well as RhD, have been identified properly. The donated blood has been tested negative for other diseases like human immunodeficiency virus or hepatitis. 

Clinical Reports

Scientific studies have shown positive results for the use of convalescent plasma therapy in curing infected patients. In one research study, clinical symptoms and paraclinical criteria showed an improvement, lung lesions showed degrees of absorption, and viremia disappearances were reported to have improved.

In another publication, they claim to have identified that the transfusion of convalescent plasma can lead to lower mortality and shorter hospitalization. Also, it was mentioned that there were no adverse effects or complications observed in patients who had received the therapy.

Additionally, an improvement in clinical status (normalization of body temperature, decreased SOFA score, and viral loads) was noticed following a transfusion in a study published last March. 

Convalescent Therapy

Although new studies attest to the effectiveness of plasma convalescent therapy, we should remember that everyone has unique biological attributes that can influence the efficacy of certain medical interventions. There are risks associated with this therapy, just like with any other. These include the following: 

• Possible circulatory overload
• If the receiving patient has severe damage in their lungs, they could develop TRALI or transfusion-associated acute lung injury
• Allergic reactions may occur for transfused blood and blood by-products

With any experimental treatment, there are always risks, so speak with your primary care physician before making any decisions. 

References

https://www.pnas.org/content/117/17/9490

https://www.thelancet.com/article/S1473-3099(20)30141-9/fulltext

https://jamanetwork.com/journals/jama/article-abstract/2763983