Strain specific CCR5 expression analysis in homozygous B-hCCR5 mice by flow cytometry. Peritoneal washes were collected from WT and homozygous B-hCCR5 (H/H) mice and analyzed by flow cytometry with species-specific anti-CCR5 antibody. Mouse CCR5 was exclusively detectable in WT mice. Human CCR5 were exclusively detectable in homozygous B-hCCR5 but not WT mice.