1015 LEUKOCYTE INHIBITION FACTOR (LIF) RELEASE BY SPECIFIC ANTIGEN STIMULATION OF CORD LYMPHOCYTES (CL)

Abstract

The transfer of specific cell-mediated immunity (CMI) from mother to fetus during pregnancy has considerable potential significance in immunization schemes. We reported previously on blast transformation (BT) in response to specific antigen of CL from infants whose mothers' cells exhibit BT to the same antigens. Karyotypic analyses of the transformed cells support the conclusion that they are the infant's and not the mother's (Fed. Res. 18: 262A, 198A).We have now demonstrated LIF generation in 24 and 48 hr cultures of CL, stimulated by purified protein derivative (PPD) or phytohemagglutinin (PHA). Indicator leukocytes from normal donors placed in wells in 2% agarose were incubated × 48 hrs in media containing LIF (LM), and controls in media without LIF or with PPD or PHA. Migration was measured by calculating the area covered by IL. Inhibition of migration (MI) is percent decrease in migration by the indicator leukocytes in LM compared to controls. CL from 17 successive babies produced LIF in presence of PHA, giving >60% MI; 5 of these also produced LIF in presence of PPD, giving >50% MI. These 5 had stimulation indices to PPD by BT of >2.0; the others did not. We conclude that the specific CMI transferred during pregnancy from the mother to the fetus in addition to response by BT to specific antigen extends to the capacity of lymphokine production. This passive CMI may account for poor immunization results with vaccines requiring a naive T-cell population reactive to certain specific antigens, eg. BCG.