MOLECULAR PROBES FOR THE LOCATION OF HUMAN SPERM-ALPHA-D-MANNOSIDASES.2. THE FITC-ALPHA-D-MANNOSYLATED-ALBUMIN

The fluorescein-labeled neoglycoprotein alpha-D-mannosylated albumin ( FITC-alpha-D-mannosylated-albumin) was used as molecular probe to dete ct alpha-D-mannose binding-sites in the human spermatozoon. The follow ing binding site-patterns were observed: homogeneous staining all over the cell (I), staining mainly in equatorial zone (II), in acrosome (i ncluding or not equatorial zone or neck) (III), in post acrosomal shea th and midpiece (IV) or in neck and midpiece (V). Comparison of the re sults with those obtained with FITC-HRP and a reinterpretation of prev ious data suggest that the FITC-alpha-D-mannosylated-albumin is a poor probe for the detection of binding sites on spermatozoa because of it s rudimentary carbohydrate chain, with broad specificity.