TNF and non-Hodgkin lymphoma: Previous studies have addressed explanations for such observations which could be due to: (i) immunosuppression from both NHL disease and its treatment may predispose patients to higher risk of coinfection, (ii) An immunomodulating effect of HHV6 since it can induce production of interleukin-1β and tumor necrosis factor-alpha, suppress T lymphocyte function due to reduced interleukin-2 synthesis [7], and suppress bone marrow by inducing interferon-alpha production.