B cells are the primary cell in the production of the humoral response, which initiates antibody mediation. Bone marrow stem cells produce pre-cursor T lymphocytes and pre-cursor B lymphocytes. B cells then develop in the bone marrow stem cells and are involved in the production of virus-specific antibodies. The T cells are involved with cell-mediated immunity. Helper T lymphocytes help stimulate the release of B lymphocyte growth factors which in turn enhance the production of plasma cells. B cells can also either block the surface of cells to prevent viral entry or they can initiate the killing of the virus and therefore reduce viral dissemination. The plasma cells can secrete antibodies that clump together with the viral antigens. This is known as an antibody-antigen complex. The antibodies can neutralize or block the virus from entering the host cell, they can attach to the infected cell, or they can also signal other immune cells for help. These other immune cells respond in a variety of ways to either destroy the virus or the infected host cells.
