Phenotypes of Peripheral Blood Lymphocytes during Acute Hepatitis A

Abstract

We investigated peripheral blood lymphocyte phenotypes of 74 patients at weekly intervals during the course of acute hepatitis A. In the second week after onset of jaundice, a significant elevation of total lymphocytes was observed (4,096 X 10(6) +/- 1,003 X 10(6)/l vs. controls 3,038 X 10(6) +/- 1,208 X 10(6)/l, p less than 0.005). However, no change in the relative percentage of B-cells (CD20+), T-cells (CD3+ or CD2+), or T-cell subpopulations (CD4+ helper cells and CD8+ suppressor cells) could be demonstrated during the course of the disease. Activated T-cells (CD3+ DR+) were elevated during the first week (204 X 10(6) +/- 134 X 10(6)l vs. normal 91 X 10(6) +/- 54 X 10(6)/l, p less than 0.005) and during the second week (202 X 10(6) +/- 82 X 10(6)/l, p less than 0.0005) after onset of disease and returned to normal values until the third week. Cells expressing phenotypes of lymphocytes capable of exerting non-MHC-restricted cellular cytotoxicity, i.e. Natural Killer cell activity (CD57+, CD16+, and CD56+) were significantly elevated in percentage in the first week of disease, as compared to controls (CD57: 14.5 +/- 7.0% vs. 9.3 +/- 5.8%, p less than 0.05; CD16: 13.4 +/- 7.3 vs. 9.5 +/- 5.1%, p less than 0.05; CD56: 10.5 +/- 3.5% vs. 8.0 +/- 1.5%, p less than 0.005). Also the absolute numbers of these lymphocyte subpopulations were found to be elevated during the first and second week. The increase in NK cells in the initial phase of acute hepatitis A suggests an important role of these cells in the first line of defence in this disease.

Natural Killer Cells in Liver Disease

“…One study suggested NK cells have the potential to control HAV infection, although this was carried out in HAV-infected fibroblasts rather than hepatocytes [75,76]. There is controversy over changes in NK cell frequency during Hepatitis A [77,78] but elevated NK cell NKG2A expression correlates with ALT, suggesting a possible role for NK cells in acute liver damage [78].…”

Acute and chronic viral hepatitis

“…Thus, there is a fairly normal nuclear : cytoplasmic ratio. 194 A substantial direct cytopathic effect of the virus on hepatocytes seems unlikely. It is most often thought to be malignancy associated, rather than directly premalignant, 170 although this concept has now been questioned in some cases.…”