What is Plasma Therapy and How Does It Work? Can It Cure COVID-19?

Several clinical trials are underway to combat the coronavirus pandemic and one is Plasma Therapy or Convalescent Plasma Therapy (CPT). 

Here we will tell you what convalescent plasma therapy is, how plasma therapy works, the history of plasma therapy, and can it be helpful in the treatment of coronavirus disease (COVID-19)?

Convalescent plasma therapy (CPT) uses blood donated by recovered patients to introduce antibodies in those undergoing treatment.

What is Convalescent Plasma Therapy (CPT), How Does Plasma Therapy Work and Can It Be Helpful in the Treatment of COVID-19?

Treatment of Coronavirus Disease

No exact treatment has been discovered for COVID-19 yet. But there are some drugs created for other diseases that have been successfully tested in some COVID-19 patients. In addition, the progress has also been reported in the development of virus-neutralizing vaccines, antibodies to major antigens, monoclonal and RNA-based vaccines. 

There is increasing discussion about the treatment of cases of new coronavirus (Covid-19) using plasma therapy, a treatment method that draws antibodies from the blood of people recovering from Covid-19 and contributes to the development of immunity and does not exacerbate the disease.

Several countries around the world have officially announced the introduction of clinical trials on this type of treatment. Therefore, convalescent plasma therapy or plasma therapy has been started in some places.
While there are many important facts that should be familiar with this type of treatment.

What is Convalescent Plasma Therapy (CPT)?

Let us now know about convalescent plasma therapy (CPT) or plasma therapy. 
Convalescent plasma therapy (CPT) is the use of antibody-rich blood donated by recovered patients and involves transfusing it in those undergoing treatment.

When pathogens attack our body, our immune system starts working and extract proteins to fight infection. These proteins are known as antibodies.

In plasma therapy, the blood of a person recovering from COVID-19, which is rich in antibodies, is used to treat other critically ill people. Under this, the plasma of the cured people is transfused from the patients.

In this therapy, an antibody is used, which is formed in the body against any virus or bacteria. This antibody is extracted from the body of a patient who has been cured of COVID-19 and put into the sick body.

When there is an effect of antibodies on the patient, the virus starts to weaken. After this, the chances of recovery of the patient increases.

If an infected person produces a sufficient amount of protein, he will recover by the antibody himself.

According to the researchers, immunity develops quickly in a person with precocious or mild symptoms or immunity develops later in seriously ill COVID-19 patients.

Plasma therapy is an ancient technique. It has been in use for decades. Until now, there is no exact cure for coronavirus disease in the world, so it is said that plasma therapy may be useful for serious corona patients.

What is Blood Plasma?

Blood plasma is a liquid material that tends to yellowish color.
Blood plasma is made up of water and protein and it contains important components of immunity known as antibodies.
The most important thing that distinguishes it is that it is formless, i.e, it does not have a specific shape, as it constitutes 55% of the total volume of blood in the human body, and it is very important to transport water, salts, nutrients, and hormones.
Blood plasma has two important functions within the body:

It transfers the nutrients needed for the cell from the place of absorption or its manufacture to the rest of the body.

It provides a medium for circulating red blood cells, white blood cells, and platelets through the body and transfers the products of metabolism processes inside the body.

What are Antibodies?

An antibody is a protein produced in our body and helps us in fighting against external harmful elements called antigens. A healthy person has thousands of antibodies in his body.
Antibodies are made up of specialized protein materials called immunoglobulins, where these bodies are produced by plasma cells (white blood cells). Immune systems make antibodies when antigens enter the body.
These antibodies are spread on the surface of (B) cells, in the blood, and in lymphoid tissues.

Each antibody consists of four polypeptides chains –the first two are large, heavy, and stable in structure, while the remaining two are smaller joined to form a "Y" shaped molecule.

The hemoglobin molecule is composed of polypeptide chains, and the number of polypeptide chains is four: two alpha chains and two beta chains. 
Alpha and beta chains have different amino acid sequences, but they fold to form similar 3D structures.

The composition of the amino acids found at the top of the chain changes, allowing the antibody to bind to specific types of antigen and inactivate them.

How Does Plasma Therapy Work?

In plasma therapy, blood is extracted from a patient who is cured with COVID-19. The serum is then separated and tested for antibodies that neutralize the virus. 
Serum containing antibodies is given to a patient with COVID-19, with severe symptoms.

According to the Houston Methodologist, the process of donating plasma takes about one hour, just like donating blood.
The plasma donors are attached to a small device that extracts the plasma, as well as returning red blood cells to their bodies.

At the same time, during regular blood donation, donors have to wait for red blood cells in between when donating. In the case of plasma, it can be donated repeatedly, i.e. twice a week.

Antibody-rich plasma is taken from patients cured with COVID-19 and then transmitted to the bloodstream of other infected coronavirus patients. 
When the body is exposed to external pathogens such as bacteria or germs, it automatically initiates a defense mechanism and starts releasing antibodies.

Coronavirus has roughly three stages. In the first stage, the virus enters the body. In the second, it reaches the lungs and in the third, the body tries to fight it and kill it,  which is the most dangerous stage. Here even the body parts get spoiled.

The best time to treat coronavirus with plasma is the second stage. Because there is no use to give it in the first and in the third it will not work. Plasma therapy can prevent a patient from going to the third stage.

History of Plasma Therapy

The concept of plasma therapy dates back more than a century when in 1890 a German physiologist Emil von Behring found that when he took serum from a diphtheria-infected rabbit, it was effective in preventing infection caused by diphtheria.

In the past, the same types of treatments have been used during several outbreaks, including the H1N1 influenza virus (Spanish flu) pandemic 1918, diphtheria outbreak 1920, etc. 

This therapy was tried for other viral diseases such as Ebola virus, SARS in 2003 and MERS in 2012. 

During the Ebola outbreak that began in 2013, plasma therapy was used to treat patients because vaccines always take time to develop.

This method was used with improved extraction and screening techniques and appeared to be safer and more effective than before.

Convalescent plasma therapy was less effective at the time and had substantial side effects.

Risks and Side Effects of Plasma Therapy 

Studies by John Hopkins immunologists have shown some of the risks associated with plasma therapy:

1. Transfer of blood substances: As blood transfusion occurs, there may be a risk that an unintentional infection may transfer to the patient and plasma transfusion can lead to adverse reactions or events.

2. Enhancement of infection: Plasma therapy may fail for some patients and may result in an increased form of infection.

3. Effect on the immune system: Antibody administration can abolish the natural immune response of the body, causing the coronavirus patient to become susceptible to re-infection later.

Can Plasma Therapy be Helpful in the Treatment of COVID-19?

According to the Food and Drug Administration (FDA), plasma therapy has already been used on patients in several outbreaks, such as SARS-CoV, H1N1, and MERS-CoV.

As COVID-19 is similar to SARS-CoV, plasma therapy may prove to be effective and safe.

Plasma therapy is currently at the experimental stage for the treatment of COVID-19 and it is necessary to conduct research and testing thoroughly to recommend plasma therapy for routine use in patients with coronavirus.

The FDA also stated that more clinical trials are needed to prove plasma therapy to be the right treatment.

'All India Institute of Medical Sciences (AIIMS) is working closely with the Indian Council of Medical Research (ICMR) to conduct a clinical trial of the effect of plasma therapy in patients with COVID-19.'

It is necessary for all institutes in India to get the necessary approval from ICMR and DCGI for plasma therapy and they should follow the appropriate clinical guidelines for this research.

In very limited studies worldwide, the plasma of a cured patient is supportive of other therapies that have provided some benefits in the management of severe COVID-19 patients.

Plasma therapy should be tested in terms of safety and that it should have adequate antibodies that are useful for patients with COVID-19.

According to the researchers, plasma therapy will not be so simple. In the case of COVID-19 which is a new pandemic where most of the patients are aged and already suffering from other diseases like high blood pressure, diabetes, etc. Therefore, how effective this therapy can be for COVID-19 treatment will be known only after research.