L-NMMA prevents TNFα- and MIP-1α–mediated inhibition of

Fancc^−/− BM colony growth.(A) In the presence of 0.5 ng/mL TNFα, colony formation byFancc^−/− BM cells was reduced, as compared with wild-type littermate controls. This was prevented by addition of 0.25 mM L-NMMA. (B) Reduction in Fancc^−/− BM cell colony numbers in the presence of MIP-1α (1 ng/mL) was inhibited by the addition of 0.5 mM L-NMMA. Data points represent the average number of colonies counted. n = 4 mice per genotype. *P < .05; **P < .005.