Figure 8.

Fluorescent photomicrographs showing co-expression of OMP with OR6B2 in control human spermatozoa. OR6B2, a marker for a human OR,⁶⁵ was co-labeled with OMP using double-labeling ICC. (A) OMP co-expresses with OR6B2 (yellow) on the EqS (arrows) of the head, and along the tail, except for the mp. DAPI (blue) stains spermatozoal nuclei. (B) Immunofluorescence shows expression of OMP (red) on the head, cp (arrowheads), and along the tail. On the head, expression of OMP is seen prominently on the EqS and faintly on the apical part of acrosomal region. OMP is also expressed in a discontinuous and punctate pattern along the tail, except for the mp. (C) Expression of OR6B2 (OR, green) is seen on the EqS of the head (arrows) and evenly along the tail, but not on the cp or mp. Scale bar = 10µm. Abbreviations: OMP, olfactory marker protein; OR, olfactory receptor (OR6B2); ICC, immunocytochemistry; EqS, equatorial segment; DAPI, 4′,6-diamidino-2-phenylindole dihydrochloride; cp, connecting piece; mp, middle piece.