Lack of short-term effects of chemokine antagonists on the number of different types of human cells present in NOD/SCID mice. Mice were transplanted with human bone marrow and 10 to 12 weeks later were given 2 injections of 10 μg of either agent (or medium), 1 day apart, and then sacrificed 1 day later. Results for MCP-1(9-76) are shown as the hatched bars, for MIP-1β as the solid bars, and for the controls as the open bars. Values shown represent the mean ± SEM of the total number of human cells, of the types shown, present in the 2 femurs and tibiae of a total of 24 mice from 4 experiments. Neither of the chemokine antagonists had a significant effect, although a slight effect of MCP-1(9-76) on LTC-IC numbers was noted (P = .02).