Kupffer cell engraftment across the major histocompatibility barrier in mice: Bone marrow origin, class II antigen expression, and antigen-presenting capacity

The source of population renewal for Kupffer cells (KC), the major antigen-presenting cells of the liver, remains controversial. Using a well-described murine bone marrow transplantation (BMT) model in which the donor and recipient are disparate at the major histocompatibility complex (MHC), we have studied (a) the source of KC renewal by genotypic analysis, cell surface (class II or la) antigens, and immune function assays; (b) the level of KC la expression post-BMT in transplant recipients; and (c) the capacity of newly repopulating KC to present antigen to an la-restricted T cell clone of donor la type. Kupffer cell engraftment, as assessed by each of these three methods, was noted to be predominantly of donor marrow origin by day 21 post-BMT. Cell surface la expression was comparable to that of nontransplanted controls of the same strain as donor mice. Within 7 days post-BMT, KC were mature antigen-presenting cells. We conclude that KC rapidly repopulate the liver from donor bone marrow post-BMT, and these macrophages are able to interact with T lymphocytes in an immunocompetent manner.