Red blood cell Alloimmunization in SCD patients

During pregnancy the antibodies and antigens production levels are traced to be abnormal in women. Such changes can affect the health of the mother and as well the new born along with many complications during pregnancy. RBC Alloimmunization is also one such condition which occurs due to the formation of antibodies to red blood cell antigens in the recipient from previous blood transfusions or a pregnancy. Sometimes this condition is also traced when the body is not exposed to foreign RBC antigens earlier before the transfusions.

The formation of antibodies in the human body differs extensively depending on the patient’s disease, history of transfusions, pregnancy and the rate of antigens production against the donors of different geographical locations. In order to trace the level of RBC Alloimmunization keeping the record of the antibody and antigen rates against the transfusions is important. Normally, the rate of red cell antibodies is estimated to be 20% or more in patients with transfusion dependent diseases like sickle cell anemia and thalassemia etc.

Sickle-cell disease (SCD) is an autosomal recessive genetic blood disorder with over dominance, characterized by red blood cells that assume an abnormal, rigid, sickle shape. Sickling decreases the cells flexibility and results in a risk of various complications. The sickling occurs because of a mutation in the hemoglobin gene during a transfusion. However, Red blood cell transfusions have reduced despair and mortality for patients with sickle cell disease. Transfusions can anyhow lead to RBC Alloimmunization.

Blood transfusion is an essential treatment for the patients with sickle cell disease (SCD). However, transfusions can lead to RBC Alloimmunization with serious complications for the patient. These antibodies produced in such conditions are often directed against antigens expressed on RBC’s of white persons, donors of western countries. However, finding such donors lacking those antigens can sometimes be difficult and identifying and characterizing the antibodies can be a time consuming job causing transfusion delays.

The most serious consequence of RBC Alloimmunization in SCD patients is the risk of developing a delayed hemolytic transfusion reaction (DHTR), which can be life taking. In many cases, the patient's hemoglobin level falls below the pre transfusion level indicating that the patient own RBCs are lysed in addition to hemolysis of the transfused RBCs. This condition is known as hyperhemolysis. Additional transfusions may provoke the hemolysis and further worsen the degree of anemia in the patients.

Not all patients develop all antibodies after exposure to transfused RBCs. This fact pertains not only to patients with SCD but also to other transfused recipients. RBC Alloimmunization cannot be entirely prevented except by transfusions from an identical twin or by autologous transfusions. Preventing RBC antibody formation is also not practical for most patients and, for man yit causes no serious complications. But prevention of RBC Alloimmunization is important in women of child bearing age, and for some patients at risk of serious haemolytic transfusion reactions. It is currently unknown whether RBC Alloimmunization rates differ depending on the presence or absence of clinical complications of SCD.

In conclusion, challenges remain for the diagnosis, prevention, and management of RBC Alloimmunization in SCD. Understanding the mechanisms and associated risk factors will aid in developing strategies to prevent and inhibit production of antibodies in transfused patients and to minimize its life threatening complications resulting from transfusions. Also, Immuno modulatory therapies, such as the use of immune cell depleting agents, costimulatory blockade, and cytokine blockade, may be effective in suppressing RBC Alloimmunization in patients. Tracing the conditions and taking timely precautions can help to recover from such complications during the pregnancy.

Hepatitis B Vaccines made from Human Plasma

Immunity plays a crucial role in the human body fighting against various diseases and infections attacking it. If a human immune system is prepared to withstand a disease it is said to be immune to the following disease. Immunity is sometimes gained naturally by suffering and surviving the infection and conquering it. This is called naturally acquired immunity. With naturally acquired immunity, one suffers the symptoms of the disease and also faces the complications, which can be sometimes dangerous. Apart from naturally acquired immunity, artificially acquired immunity can also be attained by the human body through vaccines which is the easiest and the less risky way to get immune against any disease.

Vaccine made from Biological Products prevents diseases from occurring at the first place, rather than attempting to cure it after getting it. In fact, it is cheaper to prevent a disease than to treat it as in the course time you can face many complications and also can spread it to people around you. Vaccines protect the human body against infectious diseases caused by microbes and viruses by generating antibodies in the body to fight against the infectious conditions.

Vaccines protect the human body against various diseases like chickenpox, hepatitis A, hepatitis B, and Haemophilus influenzae type b (Hib) etc.

Vaccines for hepatitis B:

Hepatitis B is a serious disease that is killing about 4k to 5k of Americans every year and 1 million people around the world. Hepatitis B is caused by infection with the hepatitis B virus, termed as HBV. Persons with HBV infection have this virus circulating in their blood, much like hepatitis C virus (HCV) and human immunodeficiency virus (HIV). Persons who become infected with HBV either recover from their infection in several months or they may remain chronically infected for most of their lifetime. Also, majority of people in U.S.A go under liver transplant each year, out of which 16% were done due to infections caused by hepatitis B.

Although most people do not show symptoms of HBV infection, however blood tests can accurately identify the conditions of the life taking disease. Adults who are chronically infected by HBV have a 15% chance of dying from liver disease whereas young children or infants have a 25% chance to die due to liver cancer. So, prevention of such infection is very crucial as if once a person is infected, there are only few treatment options available that are much expensive too.

Apparently, prevention is better than cure. Vaccines prove to be a life saving option for the persons suffering from HBV. There are about 15 different types of Hepatitis B vaccines available today around the world.

The first Hepatitis B vaccine was developed in 1981. It was derived from donated human plasma and was known as PDV (Plasma Derived Vaccine). It is prepared from particles of HBsAg obtained from human plasma, which is purified thus delivers 95% pure Biological Products. These vaccines are subjected to inactivation with formalin and heat and are adjuvant with compounds of Aluminium. Plasma derived vaccine is presently available for large-scale, public-sector purchase with valid medical prescription. It is used widely used today as the best preventive for HBV.

However, it comes with minor side effects associated with it. The vaccine is though suitable for all persons, some cases suffer through mild swelling, tenderness and redness at the place of the injection. Other minor reactions such as malaise or fever occur in less than 2% of individuals. However, more serious reactions are rare has not been detected.

The World Health Organization has stated that plasma derived vaccines (PDV’s) are safe and effective type of vaccines made from Biological Products for all age groups.

Products derived from human plasma

Plasma is a major constituent of human blood that is packed up of large number of proteins in it. These plasma proteins play a major role in transportation of blood and various other vital substances in human body. These proteins are responsible to carry out vital body functions like blood clotting, defending body against attacks by diseases, transportation of various substances in the blood and cleansing the blood by flushing out the toxins. This miracle substance plasma works as a firewall protecting the human body against external agents and keeping it healthy.

However by Donating Plasma one can contribute this substance for helping the other fellow beings. The plasma when taken out from human body can be fractionated, purified, and used to treat diseases caused from defects in these plasma components of other human bodies. Donating Plasma is helping the healthcare industry to develop range of Plasma Products that can be used as a medication in treatment of various chronic diseases.

These plasma derived proteins or Plasma Products are developed by collecting the Donating Plasma samples of thousands of donors. Once collected appropriate processing is done and the product is preserved for future use. However, the processing of plasma is very costly and time taking. Blood plasma once processed can be used in manufacture of various Plasma Products.

The major Plasma Products that are derived from human blood plasma are:

·         Intravenous Immunoglobulin (IVIG)

·         Albumin

·         Clotting Factors

·         Hyper Immunes

Intravenous Immunoglobulin (IVIG):

Intravenous Immunoglobulin (IVIG) contains pooled, polyvalent, IgG extracted from the plasma of over one thousand blood donors. It is a blood product that is administered intravenously to the patients. This Plasma Product is used to treat immune deficiencies, inflammatory and autoimmune diseases, and acute infections in the human body. When IVIG is administered to the patients it effect last up to 2weeks to 3 months in the body.

Albumin:

Serum albumin is the most abundant blood plasma protein constituting about 60% of whole blood plasma protein. It is produced in the liver and is responsible for regulating osmotic pressure of the human blood compartments. The albumins also act as carriers for molecules of low water solubility, hormones, bile salts, calcium and various drugs in the human body. Albumin is often used to replace lost body fluid and to help restore blood concentration levels in various conditions like trauma, burns and surgeries in patients.

Clotting Factors:

Clotting Factors are the unique plasma products that can be derived only form human blood plasma. They are the best known plasma products and the key components of coagulation. These plasma products are administered to patients who are genetically unable to produce all of the components necessary for Blood clotting. The most commonly known need is for Factor VIII, a Blood clotting agent, by hemophiliacs.

Hyper Immunes:

Hyper Immunes are also like Intravenous Immunoglobulin (IVIG) except that it is developed from the Donating Plasma samples of donor with high titers of specific antibody count in them. These Plasma Products administration provides passive immunity to the patient against various agents in the human body. They provide instant results but have serious side effects also associated with their dosage.

Seemingly all these plasma products are proving to be very useful in increasing the immunity of the patients and curing various diseases. By Donating Plasma all individuals can contribute in the development of medicines and vaccines form which these exclusive products to save lives of many patients around the world. Also, the donors are paid on each of their plasma donations so earning while doing a noble deed.

Methods for plasma extraction from human body

The concept of donating your plasma can sound weird to many as it is not very common today like blood donation. But Plasma Donation is similar to blood donations and to say much more safe and healthy for the human body than blood transfusions. In this type of donation only plasma, the liquid part of the blood is taken out and the blood is sent back to the donor body. Though this looks very complex to hear, but this is carried out without causing much pain to the donor. Plasma comes along with many medical benefits associated with it, it is utilized in the development of various medicines and also is used for clinical researches in laboratories.

Plasma is extracted from the human blood at the Plasma Donation Center in different ways to make use of the substance in various ways. The three ways that are majorly used for the extraction process are:

·         Plasma transfusions

·         Fractionation

·         Plasmapheresis

Plasma transfusions: It is the process in which first the entire blood is taken from a human body. The plasma is then separated from the blood by apheresis and is stored at frozen state. This stored substance is called as fresh frozen plasma (FFP). Whenever the plasma is needed it is thawed and given as a transfusion to another person.

Such Plasma transfusions comes very useful in treating patients who are bleeding due to serious accident or undergoing major surgery where clotting factors need replacing as well as red blood cells.

Fractionation: In this process different plasma donation samples are mixed (pooled) and are subjected to different heat and chemical treatments thus separating all the various proteins from the plasma. This is a very complex procedure and can take up to 5 days. The samples that are collected for the pools go through strict tests and checking to trace for all viruses and antibodies. Then the pooled plasma is carefully filtered and cleaned using heat, detergents and solvents to remove all possible viruses that may be present in it. After the fractionation process has been completed, the plasma products are either freeze dried as a powder for reconstitution before use or are stored as a liquid.

Such extractions can be useful in treating patients with the medical condition such as haemophilia.

Plasmapheresis: This is a plasma exchange method in which a cell separator machine is used to separate the plasma from the human blood. In this process a needle is inserted into a donor’s vein on the arm and the blood is extracted and passed through the cell separator. The plasma is separated from the blood in this machine and the left blood is returned back through a needle by the vein in the other arm to the donor’s body. During this process, only a little amount of blood (less than 100ml) will be taken out from the body at a single time as the blood is being removed and returned at the same rate from the body throughout the process. This procedure takes up to 2 hours to extract the required amount of plasma from a single donor.

Plasmapheresis or plasma exchange is often used to treat patients with rare blood conditions and clotting disorder.

However, all these methods are carried out maintaining full hygiene and care of the donor. Also the donor has to pass through certain tests prior to the extraction in order to get approved for Plasma Donation. Once passed through all the tests, all healthy adults can donate their plasma twice a month at any Plasma Donation Center. The donors are also been paid for giving their Plasma Donation.