mide, although the toxicity produced is greater on B cells than ... The hematological indices such ... the hemoglobin levels, platelet, reticulocyte and total leuco-.
Research Letter
Effect of cyclophosphamide pretreatment on hematological indices of Indian Bonnet monkeys Sir, The leucocytes carried along with the transplanted tissue (passenger leucocytes) are important in graf t rejection. It should be possible to greatly diminish the immunogenicity of a tissue graft if one can remove passenger leucocytes. Appropriate treatment of a tissue prior to transplantation can afford a marked reduction in its immunogenicity for the host. It is now possible to eliminate or at least reduce tissue immunogenicity by removal of leucocytes from the transplant prior to grafting. It therefore mak es good theoretical and practical sense to attempt to alter tissue immunogenicity by treating the tissue to be grafted rather than the recipient. 1 Cyclophosphamide belongs to the nitrogen mustard subclass of alkylating agents. It is an immunosuppressant that alk ylates DNA, thereby interfering with its synthesis and function, particularly in proliferating (also in non-proliferating) lymphocytes. Both B and T cells are affected by cyclophosphamide, although the toxicity produced is greater on B cells than T cells. Consequently, this drug exerts its greatest effect by suppressing humoral immunity. When cyclophosphamide is administered in very large doses, it can result in a specific tolerance to any new antigen to which it is simultaneously exposed.2 Normal adult Indian Bonnet monk eys (Macaca radiata radiata) of both se xes, weighing between 2 and 6 kg were used in these experiments. After overnight fasting, about 1 ml of the blood was collected from saphenous vein and mixed thoroughly with the anticoagulant K2 EDTA. Cyclophosphamide (60 mg/kg) was administered intraperitoneally on day 0 and 2 after collecting a blood sample both the days. On day 4 the third blood sample was collected. The hematological indices such as hemoglobin, total leucocyte, differential leucocyte, platelet and reticulocyte were estimated. Hemoglobin was estimated by the Cyanmeth hemoglobin method with drabkins solution and a photoelectric calorimeter. Total leucocyte count and platelet counts were done manually by the bulk dilution method using Turk’s and platelet diluting fluid (for mal citrate) respec-
tively. Reticulocyte count was done manually by a supravital staining at 370C for 20 min with Brilliant cresyl blue dye. Blood smears made were stained by the Leishman’s stain and differential leucocyte count done. All the blood samples were also duplicated on an automated cell counter with five-part differential capacity (coulter MAXM) and a good correlation was demonstrated. Totally, ten monkeys were used for this study. The statistical significance was determined using paired ‘t’ test and P
