Expression of complement receptors (CR) by resident liver and spleen macrophages in selected species
| Species | Liver Macrophages | Spleen Macrophages | ||
|---|---|---|---|---|
| Kupffer Cells | Red Pulp | Marginal Zone | White Pulp | |
| Human | CR1 (++)a | CR1 (—)1-b | CR1 (—)1-b | CR1 (?)a |
| CR3 (++)a | CR3 (+)1-b | CR3 (++)1-b | CR3 (—)1-b | |
| CR4 (++)a | ||||
| Murine | CR3 (—)1-c | CR3 (+)1-d | CR3 (++)1-d | CR3 (—)1-d |
| Rat | CR3 (++)1-e | CR3 (++)1-e | CR3 (+)1-e | CR3 (—)1-e |
| KCA-31-f | ||||
Tissue expression of the above receptors was analyzed by immunohistochemical techniques (a Hinglais et al., 1988;
↵1-b Buckley et al., 1987;
↵1-c Lee et al., 1986;
↵1-d Gordon et al., 1992;
↵1-e Robinson et al., 1986;
↵1-f Maruiwa et al., 1993). (++) represents strong expression (25–50% of macrophages); (+) represents poor expression (less than 15% of macrophages); (—) represents no expression; and (?) represents unknown at present. CR1 recognizes particles bearing C3b as well as C4b; CR3 (CD11b/CD18) recognizes the iC3b region that contains the amino acid sequence Tyr-Arg-Gly-Asp-Gln; CR4 recognizes surface-bound iC3b. In human spleen, white pulp macrophages refers to T zone (interdigitating reticulum cells) and B zone (dendritic reticulum cells and tangible body macrophages). KCA-3 antigen is exclusive to periportal Kupffer cell surface facing the sinusoid rather than the endothelial lining.