T-enriched spleen cells in delayed-type hypersensitivity to influenza virus in mice.

Restimulation in vitro of T-enriched spleen cells from CBA mice with influenza virus A/Bangkok 1/79/H3N2 or its hemagglutinin (HA) leads to enhancement of delayed-type hypersensitivity (DTH) to virus and HA in recipients of transfer. The enhancement of DTH measured by tail swelling is accompanied by 20-fold increase of binding affinity of transferring cells to HA measured by saturation analysis. DTH induced by HA in vivo is weaker than induced by virus in this system. However, when HA is used in vitro as a restimulating antigen of virus primed in vivo lymphocytes it leads to generation of such lymphocytes population which after transfer mediates DTH response to virus or HA to the same level as virus restimulated cells. The increase of binding affinity of restimulated T lymphocytes to HA accompanying the enhancement of DTH activity is considered in the relation to quantitative and qualitative changes of antigen binding cell populations and their role in antiviral response in this systems.