Study of Interleukin 12-Gamma interferon Axis and Natural Killer Cells in Acute Viral hepatitis

Innate immune response toward viral hepatitis plays an important defense. Nevertheless little data are known regarding the difference of the immune response according to the type of viral pathogen.

In the present study we studied natural killer cells subsets in patients with different types of hepatitis viruses (A,B,C) combined with study of interleukin 12 (IL12) gamma interferon (IFN-) axis in those patients.

The study was carried out on eighty six patients with acute viral hepatitis in addition to twenty healthy subjects as control. Blood samples were subjected to study of natural killer cells counts by flow cytometry. Furthermore, serum IL12 and IFN-were determined by enzyme linked immunosorbent assay.

Natural killer counts had statistically significant increase among patients compared to control, P=0.036. The greatest counts were among patients with acute viral hepatitis B (25.1± 4.4) and acute viral hepatitis A (24.7± 3.5). The lowest mean was among patients with acute hepatitis C (18.6± 6.8). Furthermore, there was statistically significant difference among patients and control for both IL12 and IFN-(P=0.0001, P=0.022 respectively). The highest levels were found in patients with acute viralhepatitis A for IL12 and IFN- (731.9± 403.7pg/ml, 0.7± 0.0205pg/ml respectively).

The lowest levels were found among patients with hepatitis B or IL12 and IFN(41.2± 39.5 pg/ml, 0.1± 0.04 pg/ml, respectively) and patients with hepatitis C or IL12 and IFN- (70.0± 19.7 pg/ml, 0.12± 0.05pg/ml, respectively).

The present study highlights innate immune responses to acute viral hepatitis infections represented by IL12 and interferon gamma axis associated with natural killer.Altogether these observations are in favor of the activation of innate immune responses during acute hepatits viral infections what ever its type. Nevertheless the degree of response differs according to type of infecting viruses, being extensive in hepatitis A virus thought to be associated with mild form of acute hepatitis. The least response is associated with acute viral hepatitis C infection.