SPECIFIC ANTIRESPONSES OF SCID MICE POPULATED WITH HUMAN LYMPHOID-CELLS FROM PERIPHERAL-BLOOD, UMBILICAL-CORD, BONE-MARROW AND SPLEEN AFTER IMMUNIZATION WITH GROUP-A ERYTHROCYTES

Mice with severe combined immunodeficiency (SCID) were injected i.p. with 10 x 10(6) or 50 x 10(6) human leukocytes obtained from adult peripheral blood, umbilical cord blood, bone marrow and spleen from six group 0 individuals, together with allogeneic group A erythrocytes. Mice were bled every two weeks and levels of human IgG, IgM and anti-A were determined in the murine plasma. Spleen cells elicited the highest Ig levels (up to 5.2 mg/ml IgG) and umbilical cord the least (0-0.16 mg/ml lgG); maximum IgG levels were obtained at about 6-8 weeks after injection. Anti-A was detected in mice receiving adult peripheral blood or spleen leukocytes and immunizing erythrocytes 4-6 weeks after injection. Mice injected with the higher dose of leukocytes gave the best anti-A responses, but were more likely to develop tumours after 8 weeks.