[期刊论文][Brief Report]

出版年：1997

The protective effect of primed CD4 T cells against a lethal dose of Salmonella typhimurium was studied in Lewis rats. Primed CD4 T cells were obtained by inoculating Lewis rats with a non-lethal dose of S. typhimurium . Four weeks after the infection, spleen non-adherent mononuclear cells were isolated. The cells were separated according to their expression of CD4 and the OX40 antigen by FACS. OX40 ⁺ and OX40 ⁻ CD4 ⁺ T-cell subpopulations were together with unsorted CD4 ⁺ T cells transferred to untreated rats 24 h prior to infection with S. typhimurium . Transfer of either unsorted CD4 ⁺ T cells or CD4 ⁺ T cells sorted into OX40 ⁻ or OX40 ⁻ subpopulations significantly increased animal survival compared to controls. Animals receiving OX40 ⁺ CD4 ⁺ T cells did not differ significantly in survival probability from those receiving unsorted CD4 ⁺ T cells. However, animals receiving OX40 ⁻ CD4 ⁺ T cells had a significantly better survival compared to animals given unsorted CD4 ⁺ T cells. It is concluded that OX40 ⁻ CD4 ⁺ T cells can induce significant protection against S. typhimurium infections in rats. This is most likely due to the fact that the OX40 ⁻ CD4 ⁺ T-cell population contains a significant number of antigen-specific memory T cells that have returned to a resting state.

Salmonella typhimurium;rats;experimental infection;CD4 ⁺ T cells;OX40;OX40 antigen