Testicular immune cell populations and macrophage polarisation in adult male mice and the influence of altered activin A levels

S. Indumathy, D. Pueschl, B. Klein, D. Fietz, M. Bergmann, H. C. Schuppe, N. Da Silva, B. E. Loveland, M. J. Hickey, M. P. Hedger, K. L. Loveland

Research output: Contribution to journalArticlepeer-review

9 Scopus citations

Abstract

Detailed morphological characterization of testicular leukocytes in the adult CX3CR1gfp/+ transgenic mouse identified two distinct CX3CR1+ mononuclear phagocyte (macrophage and dendritic cell) populations: stellate/dendriform cells opposed to the seminiferous tubules (peritubular), and polygonal cells associated with Leydig cells (interstitial). Using confocal microscopy combined with stereological enumeration of CX3CR1gfp/+ cells established that there were twice as many interstitial cells (68%) as peritubular cells (32%). Flow cytometric analyses of interstitial cells from mechanically-dissociated testes identified multiple mononuclear phagocyte subsets based on surface marker expression (CX3CR1, F4/80, CD11c). These cells comprised 80% of total intratesticular leukocytes, as identified by CD45 expression. The remaining leukocytes were CD3+ (T lymphocytes) and NK1.1+ (natural killer cells). Functional phenotype assessment using CD206 (an anti-inflammatory/M2 marker) and MHC class II (an activation marker) identified a potentially tolerogenic CD206+MHCII+ sub-population (12% of total CD45+ cells). Rare testicular subsets of CX3CR1+CD11c+F4/80+ (4.3%) mononuclear phagocytes and CD3+NK1.1+ (3.1%) lymphocytes were also identified for the first time. In order to examine the potential for the immunoregulatory cytokine, activin A to modulate testicular immune cell populations, testes from adult mice with reduced activin A (Inhba+/−) or elevated activin A (Inha+/−) were assessed using flow cytometry. Although the proportion of F4/80+CD11b+ leukocytes (macrophages) was not affected, the frequency of CD206+MHCII+cells was significantly lower and CD206+MHCII correspondingly higher in Inha+/− testes. This shift in expression of MHCII in CD206+ macrophages indicates that changes in circulating and/or local activin A influence resident macrophage activation and phenotype and, therefore, the immunological environment of the testis.

Original languageEnglish
Article number103204
JournalJournal of Reproductive Immunology
Volume142
DOIs
StatePublished - Nov 2020
Externally publishedYes

Keywords

  • Flow cytometry
  • Lymphocytes
  • Mononuclear phagocytes
  • Morphometry
  • Testis

Fingerprint

Dive into the research topics of 'Testicular immune cell populations and macrophage polarisation in adult male mice and the influence of altered activin A levels'. Together they form a unique fingerprint.

Cite this