PubMed Health⌕ Search

PubMed · 9717462

Integrin cell adhesion molecules on human spermatozoa.

Abstract

The expression of integrin cell adhesion molecules (ITG-CAMs) by human ejaculated spermatozoa (fresh, capacitated and acrosome reacted) was evaluated by immunocytochemical, immunofluorescence and cell-ELIS methods, using monoclonal antibodies against alpha-6 and beta-3 subunits. Both the subunits were expressed on the acrosome region in fresh spermatozoa and post acrosomal region after acrosome reaction induced by calcium ionophore. The spermatozoa of the fertile men showed significantly (P < 0.001) higher expression of alpha-6 and beta-3 ITG subunits than the subfertile men. The percentage of spermatozoa reacting with alpha-6 and beta-3 mAbs increased significantly after the loss of acrosome when compared with fresh spermatozoa. Moreover, 35-40% of spermatozoa with normal shape and none of the spermatozoa with pathological shape showed a positive reaction. The quantitative analysis carried out by ELISA suggests that the levels of these ITG subunits decreased significantly (P < 0.001) in the subfertile subjects when compared with the fertile and the difference was more for alpha-6 than the beta-3. Hence our result suggests that alpha-6 subunit may be used as a clinical marker to evaluate the sperm quality in men.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

K V Reddy, P K Meherji, S K Shahani. 1998. Integrin cell adhesion molecules on human spermatozoa.. https://pubmed.ncbi.nlm.nih.gov/9717462/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Binding of the adhesion and pathogen receptor DC-SIGN by monocytes is regulated by the density of Lewis X molecules.

Soluble DC-SIGN (CD209) bind unsialylated Lewis X epitopes that are abundantly expressed on neutrophils. Due to the low expression of unsialylated Lewis X epitopes on monocytes, no binding of soluble DC-SIGN molecules was seen. In contrast, beads coated with multiple DC-SIGN molecules show a high percentage of binding to monocytes. The increased number of DC-SIGN molecules present on the beads enable multivalent interactions between the DC-SIGN molecules and the scarce Lewis X epitopes present on monocytes. Increased expression of unsialylated Lewis X epitopes on monocytes after neuraminidase treatment coincided with enhanced binding to soluble DC-SIGN. Multiple unsialylated Lewis X epitopes in close proximity of each other are now able to interact multivalently to soluble DC-SIGN. From these findings, we conclude that firm interactions between DC-SIGN and monocytes can be established by either increasing the density of DC-SIGN molecules at the cell surface or by increasing the number of Lewis X epitopes. Regulating the number of ligands endows monocytes with the capacity to modulate binding to DC-SIGN. This may result in a bi-directional cross-talk between DC and monocytes, to modulate innate and/or adaptive immune responses.

Cell Adhesion Molecules↗

Thiocyanate-dependent induction of endothelial cell adhesion molecule expression by phagocyte peroxidases: a novel HOSCN-specific oxidant mechanism to amplify inflammation.

Both eosinophil peroxidase (EPO) and neutrophil myeloperoxidase (MPO) preferentially oxidize SCN(-) to generate HOSCN, a weak, sulfhydryl-reactive oxidant, as a major physiologic product. We here show that HOSCN is a uniquely potent phagocyte oxidant inducer of E-selectin, ICAM-1, and VCAM-1 expression in HUVEC as detected by Western blot and flow cytometry. EMSA and inhibitor studies show that HOSCN up-regulation of these adhesion molecules is transcriptionally mediated through a mechanism that is dependent upon activation of the NF-kappaB p65/p50 transcription factor and constitutively suppressed by PI3K-Akt pathway activity. HUVEC monolayers exposed to HOSCN bind 8-fold more neutrophils and 3- to 4-fold more Aml14.3D10 cells (a differentiated cell line model of mature eosinophils) than control monolayers. Blocking Ab studies confirm the involvement of E-selectin and ICAM-1 but not VCAM-1 in neutrophil adhesion and of all three in Aml14.3D10 adhesion. Intraperitoneal injection of HOSCN evoked an 8-fold increase in neutrophil peritoneal extravasation. In addition to NF-kappaB, HOSCN also activates the potentially proinflammatory transcription factors Stat4, CDP, GRE, CBF, Ets-1/PEA3, and TFIID, a pattern easily distinguishable from that induced by LPS. These results suggest that phagocyte peroxidases function to amplify inflammation through a novel, HOSCN-specific oxidant mechanism.

Cell Adhesion Molecules↗