Characteristics of human prostasomes isolated from three different sources.
BACKGROUND
Prostasomes are organelles secreted by human prostate epithelial cells and appear freely in semen. Most prostasomal functional and biochemical characteristics have been settled on basis of seminal prostasomes (SP).


METHODS
Three types of prostasomes, viz., from seminal plasma, prostate gland (native), and prostate cancer bone metastasis, were isolated and compared for their biochemical and functional characteristics.


RESULTS
Flow cytometry showed that all three types of prostasomes had a similar size distribution and electrophoresis revealed close similarities in banding pattern. Also, a high cholesterol/phospholipid ratio and some marker enzymes were distinctive common features. The unusual chromogranin B (CgB)/chromogranin A (CgA) ratio with CgB in abundance over CgA, previously found only in SP, was also valid for the native (NP) and metastasis-derived prostasomes (MP). The latter prostasome type contained a 10-fold higher amount of CgA compared to the others. SP and MP showed the same promotive effect on sperm forward motility, whereas NP did not. All three prostasome types exhibited an antibacterial activity against Bacillus megaterium.


CONCLUSIONS
Since the three prostasome types were isolated from different environments, our data support the view that the common characteristics were prostasome-genuine.
Carlsson
Lena
L
Department of Medical Sciences, Clinical Chemistry Unit, University Hospital, Uppsala, Sweden.
Nilsson
Ove
O
Larsson
Anders
A
Stridsberg
Mats
M
Sahlén
Göran
G
Ronquist
Gunnar
G
D000626:Aminopeptidases / Q000032:analysis; D015415:Biomarkers; D018826:CD13 Antigens / Q000032:analysis; D002864:Chromogranins / Q000032:analysis; D018819:Dipeptidyl Peptidase 4 / Q000032:analysis; D004591:Electrophoresis, Polyacrylamide Gel; D004847:Epithelial Cells / Q000648:ultrastructure*; D005434:Flow Cytometry; D006801:Humans; D008297:Male; D015388:Organelles / Q000737:chemistry / Q000201:enzymology*; D010743:Phospholipids / Q000032:analysis; D011467:Prostate / Q000166:cytology* / Q000201:enzymology; D011471:Prostatic Neoplasms / Q000378:metabolism / Q000473:pathology*; D012661:Semen / Q000166:cytology* / Q000201:enzymology
D015415:Biomarkers; D002864:Chromogranins; D010743:Phospholipids; D000626:Aminopeptidases; C025579:enkephalin degrading enzyme; D018826:CD13 Antigens; D018819:Dipeptidyl Peptidase 4