RECIPIENT AGE DETERMINES THE SUCCESS OF INTRAPERITONEAL TRANSPLANTATION OF PERITONEAL-CAVITY B-CELLS

In vivo studies of lymphocyte biology have used intravenous (i.v.) inj ection as the primary mode of cell transfer, a protocol consistent wit h the anatomic distribution of most lymphocytes. However, for study of peritoneal cavity B cells, i.v. injection does not correlate with ana tomical localization. This report describes the restoration of B-cell function in B lymphocyte-defective X-chromosome-linked immune-defectiv e (XID) mice after intraperitoneal transfer of immunoglobulin heavy ch ain (Igh)-disparate peritoneal cavity (PerC) cells. In contrast to i.v . transfer, intraperitoneal (i.p.) transfer restored B-cell function i n young, but not adult (>8 weeks), XID mice. When host and donor Igh a llotype matched, PerC B-cell engraftment was noted in older recipients ; this reconstitution however, was also age-dependent. Migration from the peritoneum to systemic circulation was necessary for serum IgM pro duction as shown by the presence of donor antibody-secreting cells in the host spleen. Host lymphocytes also influenced the success of i.p. transplantation as severe combined immune-deficient mice, regardless o f age, exhibited donor serum IgM production. Recipient age, Igh alloty pe, and immune-deficiency were found to have an impact on the ability of i.p.-transferred PerC B cells to restore B-cell function in XID mic e.