Aplastic anemia severity and IL-6 and IL-8 blood levels.

Abstract

Introduction and aims: Aplastic anemia is a rare, fatal bone marrow disorder that is presumed to be an autoimmune-mediated illness that actively destroys haematopoietic cells through a T helper type-1 cell response. Different cell types in the bone marrow and peripheral circulation produce chemokines, such as interleukin-6 (IL-6) and interleukin-8 (IL-8). The myelopoiesis that is profoundly impaired in aplastic anemia may be inhibited by these two, as critical and powerful inhibitors. Therefore, it is conceivable that their ongoing overproduction may contribute to aplastic anemia. We performed a quantitative enzyme-linked immunosorbent assay on the peripheral blood plasma to reveal the levels of IL-6 and IL-8 and their correlation to aplastic anaemia.

Materials and methods: A total of 80 cases of aplastic anemia were included in this study, diagnosed according to the criteria laid down by the International Agranulocytosis and Aplastic Anemia study group. A total of 10 healthy individuals served as controls in this study. With the help of a commercial ELISA kit and the instructions from the kit's maker, the levels of IL-6 and IL-8 were measured in a quantitative way.

Results: Mean serum IL-6 and IL-8 levels in cases were 283.28±220.27 and 122.56±97.79 pg/ml, respectively, as compared to 7.52±1.43 and 3.42±1.73 pg/ml levels in controls. Statistically, mean IL-6, as well as IL-8 levels, were significantly higher in aplastic anemia patients than in controls (p< 0.001). Levels of interleukins were also assessed in relation to the severity of the disease. Patients with very severe aplastic anaemia had significantly higher mean IL-6 and IL-8 levels (516.71±36.73 and 220.50±23.45 pg/ml, respectively), followed by severe aplastic anaemia (198.84±150.39 and 89.82±77.18 pg/ml, respectively) and non-severe aplastic anaemia (26.71±33.40 and 10.29±2.63 pg/ml, respectively) (p<0.001).

Conclusion: Blood serum levels of IL-6 and IL-8 were increased in aplastic anemia and showed a correlation with the severity of the disease. Hence, IL-6 and IL-8 may play an important role in the immune-mediated pathophysiology of aplastic anemia and their increasing levels are giving alarming signals for timely implementation of the appropriate treatment regimen to stop further progression of the disease. Additional studies are required in order to further investigate the exact involvement and role of IL-6 and IL-8 in aplastic anemia.