DAAM1 and PREP are involved in human spermatogenesis

During differentiation of the male gamete, there is a massive remodelling in the shape and architecture of all the cells in the seminiferous epithelium. The cytoskeleton, as well as many associated proteins, plays a pivotal role in this process. To better characterise the factors involved, we analysed two proteins: the formin, dishevelled-associated activator of morphogenesis 1 (DAAM1), which participates in the regulation of actin polymerisation, and the protease, prolyl endopeptidase (PREP), engaged in microtubule-associated processes. In our previous studies we demonstrated their involvement in cytoskeletal dynamics necessary for correct postnatal development of the rat testis. Here, we used samples of testicular tissue obtained from infertile men by testicular sperm extraction and the spermatozoa of asthenoteratozoospermic patients. By western blot and immunofluorescent analysis, we found that DAAM1 and PREP expression and localisation were impaired in both the testis and spermatozoa, and in particular in the midpiece as well as in the principal and end-pieces of the flagella, as compared with spermatozoa of normospermic men. Our results provide new knowledge of the dynamics of spermatogenesis, raising the possibility of using DAAM1 and PREP as new markers of normal fertility.

MAGNETIC NANOPARTICLE BASED FLUORESCENCE IMMUNOASSAY FOR DETERMINATION OF OCHRATOXIN A

Ochratoxins are possible human carcinogens. The aim of this study is to develop a sensitive competitive immunofluorescent analysis for determination of ochratoxin A (OTA) on the base of immobilized polyclonal antibody against ochratoxin and F(ab)2 fragment on magnetic nanoparticles (MNPs). Competitive immunoassay was performed by using variety concentrations of OTA and constant concentration of fluorescein isothiocyanate (FITC) labeled OTA. The analytical characteristics of the analysis with immobilized polyclonal antibody and F(ab)2 fragment were very closely.