A pilot study on observations on CD4 & CD8 counts in healthy HIV seronegative individuals

Abstract

Background & objectives: CD4 T lymphocyte count is used to measure the progression of HIV infection and is recommended as part of the standard care of HIV infected person. Information on reference CD4 counts and CD4:CD8 ratio in healthy individuals is lacking in India. Therefore the present study was undertaken to obtain base-line data on CD4 counts and CD4:CD8 ratio of healthy population from north India and to assess the feasibility of using the values as reference in an extended larger study.

Methods: In this pilot study 84 HIV negative healthy volunteers (56 males, 28 females) in the age group of 20-59 yr and who were willing to participate in the study were enrolled after proper counseling. Blood specimens were collected from each subject and processed for anti-HIV antibodies for exclusion of HIV. CD4 and CD8 counts of the samples were performed by fluorescence activated cell sorting (FACS).

Results: The mean +/- SD of the absolute numbers of CD4 and CD8 lymphocytes/microliter was 763.6 +/- 226 and 547.5 +/- 190 in males and 797.9 +/- 263 and 567.7 +/- 250 in females. The range of the CD4 and CD8 counts was 365-1328 and 264-991 in males and 415-1257 and 224-1126 in females respectively. The mean +/- SD of the CD4:CD8 ratio was 1.47 +/- 0.42 in males and 1.52 +/- 0.45 in females.

Interpretation & conclusion: The results of this study showed that there is wide variability in CD4 count in our population, as is seen in studies reported from other parts of India. A large multicentric study could define the normal range for CD4 and CD8 counts and CD4:CD8 ratio in the Indian population.