J Vet Sci.  2007 Jun;8(2):107-110. 10.4142/jvs.2007.8.2.107.

Immunohistochemical study of osteopontin in boar testis

• Kim S
• Shin T

• KMID: 1089659
• DOI: http://doi.org/10.4142/jvs.2007.8.2.107

Abstract

The expression of osteopontin (OPN) in boar testis was studied. Western blot analysis detected 66- and 32-kDa OPN immunopositive bands in the testes of adult boars. In postnatal piglets, the 66-kDa OPN band was detected in the testes, but not the 32-kDa band. In the newborn testis, OPN immunostaining was seen in gonocytes and in some supporting cells in the seminiferous tubules, as well as in interstitial Leydig cells. In the adult boar testis, OPN immunoreactivity was detected in seminiferous tubules with varying intensities. Intense OPN immunostaining was seen in the residual bodies and acrosomes in the spermatids while, occasionally, OPN immunostaining was seen in spermatogonia and various stage of spermatocytes but in few Sertoli cells in the seminiferous tubules. In addition, Leydig cells in adult boars were weakly immunostained with OPN. These findings suggest that OPN is detected in the majority of germ cells and is involved in spermatogenesis in boar testis.

Keyword

boar; osteopontin; testis

MeSH Terms

Animals
Animals, Newborn
Blotting, Western/veterinary
Immunohistochemistry/veterinary
Leydig Cells/metabolism
Male
Osteopontin/*biosynthesis
Sertoli Cells/metabolism
Spermatogenesis/physiology
Spermatozoa/metabolism
Swine/*metabolism
Testis/cytology/*metabolism

Figure

• 

  Fig. 1 Histology of the testes of postnatal (A) and adult (B) boars. (A) In the postnatal boar, sex cords and interstitial cells were seen. Undifferentiated supporting cells are positioned along the edges of the cords, while gonocytes, the precursors of spermatogonia, are located in the interior of the cords. (B) In the adult boar, there were interstitial cells and seminiferous tubules containing primary spermatocytes, spermatids, and Sertoli cells. H&E stain. bar = 50 µm.

• 

  Fig. 2 A representative photo of a Western blot analysis of osteopontin (OPN) and beta-actin in the testes of postnatal and adult boars. The molecular sizes of standard proteins are shown on the left. Major and minor OPN bands were observed at the expected sizes of 66 and 32-kDa, respectively.

• 

  Fig. 3 Immunohistochemical analysis of osteopontin in the testes of postnatal (1 day old) (A) and adult (B, C) boars. (A) In the postnatal testis, osteopontin diffusely immunostained the testis, including the seminiferous tubules and interstitial cells. Gonocytes (arrows) in the undifferentiated tubules are typically immunopositive for OPN. (B) In the adult boar, intense osteopontin immunostaining was seen in the residual bodies (arrows) and acrosomes of spermatids in the seminiferous tubules, while OPN immunostaining was seen in spermatogonia, and various stage of spermatocytes as well as in some Leydig cells. (C) OPN-positive acrosomes (arrows) in spermatids are well visualized in an adjacent tubule. A-B; Counterstained with hematoxylin. bar = 50 µm (A and B), 20 µm (C).

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