LIMITATION OF HU-PBL-SCID MOUSE MODEL IN DIRECT APPLICATION TO IMMUNOTOXICITY ASSESSMENT

Hu-PBL-scid mice were directly introduced to the methods of immunotoxi city assessments. Human IgG and IgM was detected 1 week after transpla ntation. Cyclosporin A (CsA) and cyclophosphamide (CP), which were inj ected i.p. 4 weeks after transplantation, decreased the serum concentr ation of IgM after 2-4 days of treatment but not that of IgG. Lymphocy te proliferation induced by various mitogens and primary T-dependent a ntibody responses to sheep red blood cells could not be measured by us ing splenocytes of hu-PBL-scid mice. These results were correlated wit h the fact that human cells were not detected in the spleen, thymus, o r blood of hu-PBG-scid mouse but were detected in lymph nodes of the i ntestine, which were observed by flow cytometric and immunohistochemic al examinations. The present results suggest using hu-PBL-scid mice in routine immunotoxicity investigations; lymph nodes of intestines coul d be used as the lymphocyte sources. In addition, the determination of serum Ig concentration might be used as a experimental item. (C) 1997 Elsevier Science Inc.