Membrane-associated gamma-glutamyl transferase and alkaline phosphatase in the context of concanavalin A- and wheat germ agglutinin-reactive glycans mark seminal prostasome populations from normozoospermic and oligozoospermic men

Ups J Med Sci. 2020 Feb;125(1):10-18. doi: 10.1080/03009734.2019.1690603. Epub 2019 Nov 27.

Abstract

Background: Human seminal prostasomes are intrinsically heterogeneous extracellular vesicles (EVs) whose composition is, additionally, influenced by different physiological conditions. Aiming at the molecular properties of the prostasomal surface exemplified by glycan compositions as a possible distinction factor, we applied lectin-affinity chromatography (LAC) as a new tool for their separation. Since glycans, generally, exhibit various biological activities, introduction of glyco-parameters as reference could upgrade standardization of EVs isolated by different methods and intended for use in biomedicine.Methods: Preparations of seminal prostasomes from normozoospermic (sPro-N) and oligozoospermic (sPro-O) men were subjected to LAC on concanavalin A (Con A) and wheat germ agglutinin (WGA) columns. Prostasomes recovered in LAC-separated fractions were characterized according to the distribution of selected markers: gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), tetraspanin CD63, and total protein/glycoprotein composition.Results: Two CD63-immunoreactive populations exhibiting prostasome signature bands but differing in GGT activity and surface glycans were separated on the WGA column. Additional populations having distinct profiles of total glycoproteins and which can be tracked down by ALP activity were enriched on the Con A column. WGA-separated populations were similar in sPro-N and sPro-O, whereas Con A-separated ones were strikingly different.Conclusions: Membrane-associated gamma-glutamyl transferase and alkaline phosphatase in the context of Con A- and WGA-reactive glycans mark seminal prostasomes populations from normozoospermic and oligozoospermic men.

Keywords: Alkaline phosphatase; gamma-glutamyl transferase; lectin-affinity chromatography; seminal prostasomes; surface glycans.

MeSH terms

  • Alkaline Phosphatase / metabolism*
  • Case-Control Studies
  • Cell Membrane / enzymology
  • Chromatography, Affinity / methods
  • Concanavalin A / metabolism*
  • Extracellular Vesicles / enzymology
  • Extracellular Vesicles / metabolism
  • Humans
  • Male
  • Oligospermia / enzymology
  • Oligospermia / metabolism*
  • Prostate / enzymology
  • Prostate / metabolism*
  • Semen / enzymology
  • Semen / metabolism*
  • Wheat Germ Agglutinins / metabolism*
  • gamma-Glutamyltransferase / metabolism*

Substances

  • Wheat Germ Agglutinins
  • Concanavalin A
  • gamma-Glutamyltransferase
  • Alkaline Phosphatase

Grants and funding

This work was supported by the Ministry for Science, Education and Technological Development of the Republic of Serbia, under Grant 173010.