Figure 8. Transferred K^d-reactive antibodies mediate K^d cardiac graft injury in RAG-1^−/−recipients.

Groups of 4–5 RAG-1^−/− recipients of B6.K^d cardiac allografts were treated on days 8 and 9 post-transplant with 200 μg of control rat IgG or anti-K^d mAb or 400 μl pooled serum from CCR5^−/− mice that had rejected B6.K^d cardiac allografts. The allografts were harvested from the RAG-1^−/− recipients on day 10 post-transplant. (A) Prepared sections were stained with hematoxylin and eosin or with C4d specific antibody for immunohistochemical analysis. Sections shown are representative of 4 grafts analyzed in each group. Magnification, 200x. (B) B6.K^d cardiac allografts were retrieved from RAG-1^−/− recipients treated with control rat IgG or with anti-K^d mAb. Whole cell mRNA was isolated from graft tissue homogenates and the levels of mRNA encoding CXCL1, CXCL2, myeloperoxidase, perforin and CCL5 were determined by quantitative RT-PCR. Data indicate mean mRNA expression levels ± SEM for 4–5 grafts per group. *p < 0.05, n.s.= P>0.05.