Prostasomes: a role in prostatic disease?

Immunologically Mediated Male and Female Reproductive Failure

“…Several proteins have also been identified in prostasomes associated with the enhancement of sperm motility, calcium homeostasis, semen liquefaction, complement inhibition, and clotting activation (Stewart, 2004). Tarazona et al (2011) have shown by flow cytometric analysis that prostasomes express high levels of CD48, the ligand for the NK cell activating receptor CD244, and may modulate NK cell cytotoxicity or lead to inhibition of cytokine secretion.…”

Human prostasomes express CD48 and interfere with NK cell function

“…These vesicles are rich in cholesterol (Arienti et al 1998), calcium (Arienti et al 2001) and several surface proteins (Stewart et al 2004) and after fusion with sperm cells enhances mobility (Arienti et al 1999), acrosome reaction (Palmerini et al 2003) and liquefaction of semen .…”

What are Prostasomes?

“…By adhering to and undergoing hydrophobic fusion with spermatozoa prostasomes allow lipids, carotenoids (such as lycopene), proteins and ions (as Zn þþ , Ca þþ ) to be directly transferred into spermatozoa (2,4,6,8,11). Thus the sperm membrane becomes enriched in cholesterol, sphingomyelin and saturated glycerophospholipids, proteins, enzymes and low molecular compounds.…”

“…Proteins mediating these effects include protein kinases, CD13, CD59, CD142, angiotensin converting enzyme (ACE) and chromogranin A (5,6,8,12,13). …”

“…This fusion is important in aiding the passage of sperm, and their survival in the lower and upper female genital tract to penetrate the zona pellucida and to reach the oocyte for fertilization. Prostasomes are involved in: modulation of cation levels (Zn þþ , Ca þþ ) in sperm environment and enhancement of sperm motility by transfer of calcium by ATPase and annexin's calcium channels (1, 4, 6, 11); sperm capacitation and acrosome reaction (4, 6); semen coagulation and liquefaction via PSA, tissue factor (CD142) and protectin (CD59) (2,8,10); antioxidant action by transferring their unique lipids and by inhibiting NAPDH-oxidase activity of leucocytes (5,6,8); antibacterial activity due to hCAP-18 and immunosuppression by CD46, CD55 and CD59 (2,3,5,8).…”