Prostasomes are extracellular vesicles (40-500 nm in diameter) secreted by the prostate

gland In animals, a gland is a group of cells in an animal's body that synthesizes substances (such as hormones) for release into the bloodstream (endocrine gland) or into cavities inside the body or its outer surface (exocrine gland). Structure De ...

epithelial cells into seminal fluid. They possess an unusual lipid composition and a tight and highly ordered structure of their lipid bilayer membrane, resembling that of lipid raft domains. Prostasomes appear to improve sperm motility and protect against attacks from the female immune defense during the passage to the egg. The name prostasomes was coined in the early 1980s by combining the terms "prosta"=prostate and "soma" (Greek for "body"). Around this time, the first functional studies of prostasomes were also performed. Cancerous prostate cells and prostate cells with low differentiation continue to produce and secrete prostasomes. Possibly, the high incidence of

prostate cancer Prostate cancer is cancer of the prostate. Prostate cancer is the second most common cancerous tumor worldwide and is the fifth leading cause of cancer-related mortality among men. The prostate is a gland in the male reproductive system that sur ...

in elderly men could be due to the immunomodulatory properties of prostasomes, protecting the cancer from attack by the immune system. Fusion of prostasomes with the sperm plasma membrane is required for regulation of different aspects of sperm function, such as motility and capacitation. Prostasomes have also been implicated in the interaction between prostatic cancer cells and their microenvironment. Immune regulating proteins found in prostasomes include: amino-peptidase N ( CD13); dipeptidyl-peptidase IV ( CD26); enkephalinase (neutral endopeptidase,

CD10 Neprilysin (), also known as membrane metallo-endopeptidase (MME), neutral endopeptidase (NEP), cluster of differentiation 10 (CD10), and common acute lymphoblastic leukemia antigen (CALLA) is an enzyme that in humans is encoded by the ''MME'' ge ...

); angiotensin converting enzyme (ACE, CD143); tissue factor TF ( CD142, thromboplastin); decay accelerating factor (

CD55 Complement decay-accelerating factor, also known as CD55 or DAF, is a protein that, in humans, is encoded by the ''CD55'' gene. DAF regulates the complement system on the cell surface. It recognizes C4b and C3b fragments that are created during a ...

); protectin ( CD59, inhibitor of MAC) and complement regulatory membrane cofactor protein ( CD46). Prostasomes also contain high levels of the divalent cations: Zn²⁺, Ca²⁺ and Mg²⁺.

Historical background of prostasome research

References

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Historical background of prostasome research

See also

References