1Department of Virology, PGIMER, Chandigarh, India.
2Department of Internal Medicine, PGIMER, Chandigarh, India.
Abstracts of the papers presented at the XVIII National Conference of Indian Virological Society at Post Graduate Institute of Medical Education and Research, Chandigarh, India, December 11–13, 2008.
CMV infection one of the most common refractory opportunistic infection complicating organ transplantation and other immunodeficiency syndromes. Thus there is a demand for rapid reliable methods for detection of current CMV infection. Among all the available methods, detection of CMV antigen in peripheral blood polymorphonuclearI (PMN) cells is a rapid and sensitive technique. There are different methods available for separation of PMNs from whole blood. Ficoll Hypaque method is expensive. In the developing countries there is a need for less expensive technique. Thus the current study was planned to compare ammonium chloride technique with Ficoll based technique. Total of 25 blood samples received for pp65 antigen detection were included. In Ficoll method, 2–3 mL of blood was overlaid on 2–3 mL of Ficoll in a centrifuge tube. Buffy coat was collected after 30 min centrifugation. In ammonium chloride method, 3–4 mL of 1% ammonium chloride and 1 mL of blood was allowed to stand for 10 min. Pellet collected after 10 min centrifugation and washed in PBS. Smears prepared from the cells thus obtained from both the technique were subjected for immuno-fluorescence (IF) stain using monoclonal antibody for the detection of CMV pp65 antigen and to Giemsa stain for differential leukocyte count. In the ammonium chloride method the average percentage PMN and lymphocyte was 53% and 43% as against 50% and 47% in Ficoll method. No difference was noted in the leukocyte count by two methods. Two out of 25 samples were positive for CMV pp65 antigen by both the methods. Ammonium chloride method is found to be equally good in separation of the PMNs as Ficoll method without losing the viral antigen. The morphology of leukocyte was preserved in both. Positivity found to be cost effective having the potentiality of replacing Ficoll for separation of leukocytes.
