The major histocompatibility complex requirement for cellular collaboration in the murine lymphoid procoagulant response stimulated by bacterial lipopolysaccharide
Levy, G.A.; Edgington, T.S.
Journal of Immunology 128(3): 1284-1288
1982
ISSN/ISBN: 0022-1767 PMID: 7035563 Document Number: 186002
The genetic and cellular requirements for the collaborative induction of the monocyte and macrophage procoagulant (PCA) response in the mouse were characterized using the model stimulus lipopolysaccharide (LPS). When lymphocytes were mixed with monocytes or splenic macrophages from H-2 incompatible mice there was no PCA response, suggesting that the lymphocyte collaboration required for this response is genetically restricted. When compatibility was preserved from I-E to the left by mixing lymphocytes from A strain mice with monocytes from C3H mice, full induction of the PCA response by LPS followed; compatibility to the right of I-E did not mediate the response. Requirements for compatibility at I-J and I-E were excluded by the lack of responses with the use of cellular crosses between B10.A(5R) and C3H mice. Provision of compatibility at K did not permit collaboration; cellular crosses of B10.A(4R) and C3H cells, which are compatible at both K and I-A loci, permitted full expression of PCA, indicating that I-A compatibility alone was sufficient. This was further confirmed by the cellular cross of B10.A(4R) with A.TL, which is compatible only at I-A. I-B participation was excluded by the lack of collaboration between B10.A(4R) and C3H cells as well as B10.A(4R) with A.TL cells. On the basis of the full expression of the PCA response by all cellular combinations sharing I-A, there is no evidence for secondary effects of other genetic loci on the response. Whether the I-A gene product per se or a closely linked gene product mediates this collaboration is not yet known; however, these studies provide evidence for a further role of I-A in cellular communication. In the presently described PCA response it appears to be unidirectional, i.e., from the lymphocyte to the monocyte or macrophage.