Related Experiment Video
Updated: Jun 6, 2025
An Ectopic Chemokine Expression Model for Testing Macrophage Recruitment In Vivo
Published on: September 25, 2019
EphB4 and ephrin-B1 expression in the intra-testicular-resident macrophages in mice
Md Royhan Gofur1, Kazushige Ogawa2
1Department of Veterinary and Animal Sciences, University of Rajshahi, Rajshahi, Bangladesh.
Objective:
The objective was to find out the expression of EphB4 receptor and ephrin-B1 ligand by the macrophages that live inside the mouse testicles.
Materials And Methods:
Messenger ribonucleic acid (mRNA) expression of EphB4 and ephrin-B1 was identified via RT-PCR amplification, and protein expression was examined by immunostaining.
Results:
Analysis using RT-PCR revealed that mRNA of EphB4 and ephrin-B1 were noticed in the examined testis of all postnatal ages. Furthermore, immunostaining revealed that F4/80-positive intra-testicular-resident macrophages were located in the intertubular spaces within the testis and more densely around the intra-testicular excurrent duct system, and increased in number gradually during the postnatal period of development until 5 weeks of age, when the mice attain their maturity (puberty), and maintained thereafter. Both EphB4 and ephrin-B1 immunoreactivity were noticed in F4/80-positive intra-testicular-resident macrophages within the testis of all studied postnatal ages. Ephrin-B1 and EphB4 immunoreactivity were weak during early postnatal development until the age of 2 weeks, and then ephrin-B1 immunoreactivity became very strong and EphB4 immunoreactivity became strong at the age of 3 weeks, and they continued to do so until the age of 8 weeks. Furthermore, EphB4 receptor was tyrosine-phosphorylated in testis.
Conclusion:
The expression of EphB4 and ephrin-B1 in mice intra-testicular-resident macrophages is being examined for the first time in this work. The localization of EphB4 and ephrin-B1, and EphB4 tyrosine-phosphorylation suggest that EphB4/ephrin-B1 signaling might occur in the intra-testicular-resident macrophages, and may participate in maintaining male fertility.
Insights
This study investigated EphB4 receptor and ephrin-B1 ligand expression in mouse testicular macrophages. These molecules are present and potentially active, suggesting a role in male fertility.
Area of Science:
- Reproductive biology and immunology
- Cell signaling in testicular microenvironment
Background:
- Macrophages are immune cells found in various tissues, including the testes.
- The EphB4 receptor and ephrin-B1 ligand are involved in cell-cell communication and tissue development.
- Their specific roles in testicular macrophages and male fertility are not well understood.
Purpose of the Study:
- To determine the expression of the EphB4 receptor and ephrin-B1 ligand in macrophages within the mouse testis.
- To investigate the developmental changes in these molecules and their localization.
- To explore the potential involvement of EphB4/ephrin-B1 signaling in testicular macrophages.
Main Methods:
- Messenger ribonucleic acid (mRNA) expression was analyzed using reverse transcription-polymerase chain reaction (RT-PCR).
- Protein expression and localization were examined through immunostaining techniques.
- Tyrosine phosphorylation of the EphB4 receptor was assessed.
Main Results:
- Both EphB4 and ephrin-B1 mRNA were detected in mouse testes across all postnatal ages studied.
- F4/80-positive macrophages, expressing EphB4 and ephrin-B1, were identified in intertubular spaces and around the excurrent duct system, increasing with age until puberty.
- EphB4 receptor tyrosine phosphorylation was observed, indicating signaling activity.
Conclusions:
- This study provides the first evidence of EphB4 and ephrin-B1 expression in mouse intra-testicular macrophages.
- The localization and phosphorylation suggest active EphB4/ephrin-B1 signaling within these cells.
- This signaling pathway may play a crucial role in maintaining male fertility.
