Either B7-1 or B7-2 is required for Listeria monocytogenes-specific production of gamma interferon and interleukin-2.

Listeria infection results in the induction of gamma interferon (IFN-gamma)-producing T lymphocytes. Blocking of the costimulatory molecule B7 in vivo led to a marked decrease in antigen-specific production of IFN-gamma and interleukin-2 by lymphocytes. Blocking of both B7-1 (CD80) and B7-2 (CD86) was required in order to inhibit cytokine production, indicating that either molecule could act alone. Although IFN-gamma production by cultured spleen cells was significantly suppressed by B7 blocking, mice cleared primary and secondary Listeria infection as effectively as control mice.