Murine neonates develop vigorous in vivo cytotoxic and Th1/Th2 responses upon exposure to low doses of NIMA-like alloantigens.
Early life exposure to noninherited maternal antigens (NIMAs) may occur via transplacental transfer and/or breast milk. There are indications that early life exposure to NIMAs may lead to lifelong tolerance. However, there is mounting evidence that exposure to NIMAs may also lead to immunologic priming. Understanding how these different responses arise could be critical in transplantation with donor cells expressing NIMAs. We recently reported that murine neonates that received a transplant of low doses of NIMA-like alloantigens develop vigorous memory cytotoxic responses, as assessed by in vitro assays. Here, we demonstrate that robust allospecific cytotoxicity is also manifest in vivo. Importantly, at low doses, NIMA-expressing cells induced the development of in vivo cytotoxicity during the neonatal period. NIMA-exposed neonates also developed vigorous primary and memory allospecific Th1/Th2 responses that exceeded the responses of adults. Overall, we conclude that exposure to low doses of NIMA-like alloantigens induces robust in vivo cytotoxic and Th1/Th2 responses in neonates. These findings suggest that early exposure to low levels of NIMA may lead to long-term immunologic priming of all arms of T-cell adaptive immunity, rather than tolerance.
Department of Microbiology and Immunology, University of Miami Miller School of Medicine, FL 33136, USA.
Shannon J
SJ
Opiela
Robert B
RB
Levy
Becky
B
Adkins
D000818:Animals; D000831:Animals, Newborn; D003602:Cytotoxicity, Immunologic; D004306:Dose-Response Relationship, Immunologic; D007108:Immune Tolerance; D007156:Immunologic Memory; D007519:Isoantigens / Q000276:immunology*; D051379:Mice; D009035:Mothers; D018417:Th1 Cells / Q000276:immunology*; D018418:Th2 Cells / Q000276:immunology*
D007519:Isoantigens