Immunosuppression in the Mouse by Porcine Uterine Secretory Protein

: Experiments were performed to determine whether uterine secretory proteins (PAP) of the pig affect T cell or B cell functions in vivo. T cell functions examined were E-rosette formation (ERF) and cutaneous reactivity (to phytohemagglutinin) in mature BALB/c females. Two ERF experiments of identical design were performed using five groups of ten mice each. Each mouse was presensitized with sheep erythrocytes (SRBC) designated as day 0; and the various groups were treated with saline, pig serum (PS), or PAP at different times. For cutaneous reactivity, the area of erythema at the sensitization site (pinnea of ear) was measured, and three groups of 11 mice were used. These groups also received either PS or PAP. B cell function was examined by measurements of hemagglutination titers to SRBC sensitization in BALB/c females treated in two experiments similar to the ERF. T cell functions examined were highly suppressed (p < 0.01) by PAP given hours, not days, prior to the measurement. The B cell function examined was not affected by PAP.