THE EFFECT OF ADOPTIVE TRANSFER OF MONONUCLEAR LEUKOCYTES FROM AN ADULT DONOR ON SPONTANEOUS CELL-MEDIATED CYTO-TOXICITY AND RESISTANCE TO TRANSMISSIBLE GASTROENTERITIS IN NEONATAL PIGLETS

Abstract

This study attempted to establish spontaneous cell-mediated cytotoxicity effector activity in the intraepithelial lymphocytes of neonatal piglets by adoptive transfer of mononuclear leukocytes from an adult donor and determined the effect of transfer on the resistance of piglets to transmissible gastroenteritis. Cytotoxicity was determined by a Cr release assay using PK-15 cells persistently infected with transmissible gastroenteritis virus as targets. The experimental animals were inbred miniature pigs, in which a high degree of uniformity in lymphocyte-defined histocompatibility complex antigens was demonstrated by the mixed lymphocyte reaction. Adoptive transfer of 8 .times. 107 to 4 .times. 108 adult pig leukocytes established effect or activity in 8 recipient piglets, and leukocytes labeled with fluorescein isothiocyanate homed to the epithelium of the small intestine. When 4 recipients of 5 .times. 108 adult leukocytes were challenged with transmissible gastroenteritis virus, the onset of diarrhea was delayed for 24 h and the diarrhea was usually milder than in 4 untreated control piglets. The adoptive transfer of leukocytes with spontaneous cell-mediated cytotoxicity effector activity, which homed to the small intestinal epithelium, may have contributed to an increased resistance to transmissible gastroenteritis.