Background of the Study

CHAPTER 1 INTRODUCTION

A. Background of the Study

Platelets or thrombocytes are cell fragments that function in the clotting system of the body. Normal numbers range from 150,000-350,000 platelets per μL in the human blood. A change in condition of the normal number of platelets in the blood can cause defective clotting functions and bleeding disorders which may lead to hemorrhage. This change in condition may be because of 1 failing platelet production, 2 increased platelet destruction, 3 dilution of platelets, or a combination of these in the body. Thrombocytopenia is the disorder in which there is an abnormally low number of platelets in the blood which, for humans, is less than 150,000 platelets per μL of blood. Platelet transfusions are currently used to treat thrombocytopenia in patients. This may be given either prophylactically, to stop further complications, or therapeutically, to directly treat the disorder. Prophylactic platelet transfusions are considered in thrombocytopenic patients who require operations or biopsy or have sustained serious trauma because of platelet function defects. Therapeutic platelet transfusions, on the other hand, are considered in thrombocytopenic patients with disorders caused by increased platelet destruction if there is severe and potentially life-threatening bleeding. But an increase in the platelet count after the platelet transfusion is not fully-guaranteed to the patients, though an improved hemostasis is more likely Kelton and Blajchman 1979. This inefficiency of platelet transfusions in increasing the number of platelets in the blood may be because of the following factors: refractory state, red cell alloimmunization, fever, and granulocytopenia. Patients that have received multiple platelet transfusions eventually become refractory, or not responsive, to further transfusions because of the development of alloantibodies to non-autologous platelets, or platelets from other donors except the patient himself Buchholz and others 1973; Gardner 1974; Herzig and others 1975; Schiffer 1978; Nagasawa and others 1978. This is an example of a condition, called alloimmunity, in which the body gains immunity against foreign cells from another individual of the same species. Transfusion of human leukocyte antigen-matched HLA-matched platelets has been tried to solve the problem but it was observed that it also leads to the development of alloantibodies Howard and Perkins 1978. Red cell alloimmunization has also been reported as one of the factors due to the contamination of platelets by red cells and hemolytic reactions in the donor plasma Zoes and others 1977. Another problem is the fever, occurring hours after the platelet transfusion, which may be due to the formation alloantibodies already, bacterial or viral contamination, and protozoal infections in the blood. When platelet transfusions fail in increasing the platelet count of the patient, thrombocytopenia becomes severe. This condition oftentimes results to hemorrhage on the part of the patient. If this hemorrhage continues, albumin levels in the blood will decrease and the patient will develop hypoalbuminemia, a deficit of albumin in the blood. This condition necessitates albumin infusion using fractionized human serum albumin to the patient. The administration of albumin to the body can control the accompanied symptoms until the underlying condition is diagnosed andor treated. It can also be required sometimes to maintain the level of the systolic blood pressure. In humans, human serum albumin HSA is the most abundant plasma protein found in the blood, accounting for 55-60 of all the plasma proteins. It functions mainly as carrier of different materials like hormones, fatty acids, and drugs in the blood. Also, because it holds approximately 18 mL of water per gram of HSA, it is used as a plasma volume expander in the treatment of hemorrhage or shock through infusions. It is also used as a protein replacement in cases of very low protein levels in the serum. But there are also other forms of albumin other than HSA, and are found in many other animals. Bovine serum albumin BSA, for example, is found in the blood of cows. Its primary biological function has been associated with its lipid binding properties. BSA is cheap and plentiful due to the fact thats it is a natural byproduct of the cattle industry. It is often used in restriction digestion to stabilize some specific enzymes during the digestion of DNA for studies, making it ideal for determining the quantities of other particular proteins present. It is also often used in cell generation, e.g. regenerating plants from cultured guard cells, by feeding the cell a healthy amount of protein leading to faster growth and improved healing. BSA is quite stable, which makes it ideal for scientific measures, in vaccine production, medical research, and food additives. In this study, the number of platelets of thrombocytopenic Mus musculus white mice will be determined after the infusions of bovine serum albumin. The BSA will be experimented at different concentrations of BSA.

B. Objectives of the Study