THE CELLULAR IMMUNE STATUS OF HBSAG-POSITIVE CARRIERS IN MALAYSIA

The percentage of lymphocyte subsets from the peripheral blood of heal thy adults and hepatitis B surface antigen (HBsAg) carriers were analy zed by flow cytometry. The five lymphocyte subsets studied were:- T (C D3) cells, B (CD19) cells, CD4 cells, CD8 cells, Natural Killer (CD3(- )CD16(+)/CD56(+)) cells (NK cells) and the CD4/CD8 ratio. The percenta ge (mean +/- SD) for the five lymphocyte subsets from the healthy adul ts were (67.5 +/- 8.5)%, (12.4 +/- 4.5)%, (35.5 +/- 7.8)%, (36.8 +/- 8 .5)%, (17.9 +/- 8.1)% and 1.1 +/- 0.6, respectively. HBsAg carriers po sitive for HBV-DNA had a lower CD4/CD8 ratio than the healthy populati on (P = 0.030), The percentage of CD8 cells in HBsAg carriers increase d significantly (r = 0.28; P = 0.019) with an increase in ALT levels b ut the values remained within normal range. The percentage of NK cells and CD4/CD8 ratio in HBsAg carriers positive for anti-HBe were higher than HBsAg carriers negative for anti-HBe (92% of which are HBeAg pos itive) (P = 0.045 and P = 0.035, respectively). The CD4/CD8 ratio in H BsAg carriers negative for anti-HBe (92% positive for HBeAg) was also lower than in the healthy population (P = 0.042). HBsAg carriers posit ive for HBV-DNA, HBeAg and raised ALT levels had a lower CD4/CD8 ratio than did the healthy population. The lower ratio was due to an increa se in the percentage of CD8 cells. This suggests an activated immune r esponse triggered by the infection in an attempt to clear the virus. H BsAg carriers with normal ALT levels and who are negative for HBV-DNA may be in a state of tolerance.