PERITONEAL GAMMA-DELTA T-CELLS INDUCED BY ESCHERICHIA-COLI INFECTION IN MICE - CORRELATION BETWEEN THY-1 PHENOTYPE AND HOST MINOR LYMPHOCYTE-STIMULATING PHENOTYPE

We found that gammadelta T cells increased in number in the peritoneal cavity after i.p. inoculation with Escherichia coli (ATCC 26) in mice . The increase of the gammadelta T cells was most prominent on day 5 a fter inoculation when the pathogens had been already eliminated from t he hosts. Two-color flow cytometric (FCM) analysis revealed that these gammadelta T cells in infected C57BL/6 mice expressed Thy-1 Ag on the ir cell surface. On the other hand, gammadelta T cells induced by E co li inoculation in C3H/He mice contained Thy-1-negative gammadelta T ce lls in addition to the Thy-1-positive gammadelta T cells. In both stra ins, irrespective of Thy-1 Ag expression, these gammadelta T cells wer e CD5 negative, CD44 positive, L-selectin negative, Ly-6C negative, an d IL-2R low positive. Analyses of peritoneal exudate cells (PEC) from several other strains of mice after E. coli inoculation suggested that Thy-1-negative gammadelta T cells appear in mice carrying endogenous superantigen specific for Vbeta3, especially mammary tumor virus-6. Th ese findings suggest that Thy-1 Ag expression on the gammadelta T cell s appearing in the peritoneal cavity after i. p. E. coli inoculation i s correlated to the Mls phenotype of the host mice.