B7-H3 promoted sperm motility in humans.
OBJECTIVE
To determine whether seminal B7-H3 levels are correlated to semen parameters and affect human sperm functions.


METHODS
A total of 83 healthy donors of proven fertility (aged 22-37 years) and 176 infertile men (aged 21-38 years) were recruited. Computer-assisted semen analysis and enzyme-linked immunosorbent assay were used to assess the correlations between seminal B7-H3 levels and semen parameters. Flow cytometry and fluorescence microscopy were used to detect the putative receptor for B7-H3. Computer-assisted semen analysis and FITC-conjugated pisum sativum agglutinin staining were performed for assessing sperm motility, capacitation, and acrosome reaction (AR) after incubation with various concentrations of B7-H3 for 0-4 hours in vitro.


RESULTS
Seminal B7-H3 level was significantly higher in the healthy donors than that in the infertile men (P <.05), and closely associated with sperm concentrations and progressive motility (all P <.05), but not the other parameters examined (all P >.05). A putative receptor for B7-H3 was detected on the surface of sperm, with no significant differences in expression between the healthy donors and infertile men (P >.05). Seminal B7-H3 promoted sperm progressive motility in a time- and dose-dependent manner in vitro, although having no significant influence on sperm capacitation and AR.


CONCLUSIONS
B7-H3 showed a favorable effect on human sperm motility, without affecting sperm capacitation and AR.
Department of Urology, The First Affiliated Hospital of Soochow University, Suzhou, China.
Xuedong
X
Wei
Reproductive Medicine Center, The First Affiliated Hospital of Soochow University, Suzhou, China.
Zigang
Z
Li
Clinical Immunology Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, China.
Guangbo
G
Zhang
Department of Urology, The First Affiliated Hospital of Soochow University, Suzhou, China.
Hexing
H
Yuan
Reproductive Medicine Center, The First Affiliated Hospital of Soochow University, Suzhou, China.
Jingxing
J
Lv
Department of Reproductive Laboratory Medicine, The First Affiliated Hospital of Soochow University, Suzhou, China.
Yufeng
Y
Jiang
Department of Reproductive Laboratory Medicine, The First Affiliated Hospital of Soochow University, Suzhou, China.
Wei
W
Zhang
Department of Urology, The First Affiliated Hospital of Soochow University, Suzhou, China.
Yuhua
Y
Huang
Department of Urology, The First Affiliated Hospital of Soochow University, Suzhou, China. Electronic address: xf192@163.com.
Jianquan
J
Hou
D000328:Adult; D060887:B7 Antigens / Q000032:analysis / Q000502:physiology*; D006801:Humans; D008297:Male; D012661:Semen / Q000737:chemistry; D055101:Semen Analysis; D013081:Sperm Motility / Q000502:physiology*; D055815:Young Adult
D060887:B7 Antigens; C423237:CD276 protein, human