An ascending urinary tract infection was induced by transurethral instillation of Escherichia coli mice which had an impaired T cell function from the administration of cyclosporine (impaired T cell function group). We investigated the time course fluctuation of local immune response at the infected sites in terms of immune response cells as compared with that in normal mice (control group). 100 mg/kg of Cyclosporine was administered a total of 4 times at 7, 5, 3 days and 1 day before the day of infection. Using this method of administration, the T cell function, for which we used delayed type hypersensitivity as an indicator, significantly suppressed the impaired T cell function group.
When the ascending urinary tract infection was induced by Escherichia coli, the occurrence of pyelonephritis increased and the survival rate significantly decreased in the impaired T cell function group compared to the control group, indicating a high incidence of infection.
By the time course observation of the immune response cells at the infected sites, marked infiltration of neutrophils was recognized in the impaired T cell function group as compared withthat in the control group and such infiltration remained on the same higher level thereafter. On the other hand, T, B cell infiltration was weaker in the impaired T cell function group compared to the control group.
It was therefore suggested that other immune response cells compensated for the infiltration of T cells when their function was suppressed, and that these cells on the whole possibly responded toward the preservation of their protective mechanisim against infection.