Intratesticular Expression of mRNAs of Both Interferon γ and Tumor Necrosis Factor α is Significantly Increased in Experimental Autoimmune Orchitis in Mice

Abstract

Abstract. Experimental autoimmune orchitis (EAO) is one of the models of immunological male infertility. Murine EAO is CD4+T cell-dependent and classically induced by immunization with a testicular homogenate and adjuvants. We previously established that immunization with viable syngeneic testicular germ cells (TGC) can also induce murine EAO with no use of any adjuvant. Analyses of this EAO model have already revealed that cultured spleen cells of immunized mice secreted interferon (IFN)-γ and that treatment of the immunized mice with anti-IFN-γ monoclonal antibodies significantly suppressed the EAO. It is known that both IFN-γ and tumor necrosis factor (TNF)-α are representative cytokines of Th1 cells and exhibit local toxicity toward the seminiferous epithelium in vivo. However, changes in these two cytokines in EAO-affected testes have not yet been investigated. Therefore, in the present study, we investigated the expression of intratesticular IFN-γ and TNF-α mRNAs in TGC-induced EAO using real-time RT-PCR. The results demonstrated that the intratesticular mRNAs for both IFN-γ and TNF-α significantly increased, while other cytokines such as IL-1α, IL-1β, IL-6 and TGF-β did not show dramatic changes in the immunized mice. These results suggest that secretion of significant amounts of IFN-γ and TNF-α in situ contributes to the spermatogenic disturbance in EAO. Key words: Autoimmunity, Cytokine, Spermatogenic disturbance, Testis (J. Reprod. Dev. 57: [296][297][298][299][300][301][302] 2011) xperimental autoimmune orchitis (EAO) is a model of immunologic inflammation leading to male infertility [1]. The histopathology is characterized by intratesticular infiltration of CD4+T cells, CD8+T cells, B cells and plasma cells, followed by spermatogenic disturbance [2,3]. Classically, immunization with a testicular homogenate (TH) emulsified in complete Freund's adjuvant (CFA) followed by intravenous injections of Bordetella pertussis (BP) is necessary for induction of EAO in mice [4,5]. TH+CFA+BP-induced EAO in mice is dependent on CD4+ T cells that secrete tumor necrosis factor (TNF)-α and interferon (IFN)-γ in vitro [6]. It has also been reported that the disease can be suppressed in vivo by the administration of anti-TNF-α antibodies but not anti-IFN-γ antibodies [6]. In rat EAO induced by immunization with TH+CFA+BP, it was shown that isolated testicular macrophages secreted both . However, the intratesticular changes in IFN-γ and TNF-α mRNA expression at the organ level have not yet been investigated in any EAO model.We previously established that two subcutaneous injections of viable syngeneic testicular germ cells (TGC) can induce CD4+ T cell-dependent EAO in both A/J and C3H/He mice with a very high incidence [2,10]. This model is unique in that CFA and BP are not necessary for EAO induction. However, in spite of no use of these adjuvants, it was found that delayed type hypersensitivity rather than humoral immunity against TGC antigens is critical for induction of the disease [2,11,12]. It was also shown tha...

Testicular activin and follistatin levels are elevated during the course of experimental autoimmune epididymo–orchitis in mice

“…Furthermore, TNF, a strong pro-inflammatory cytokine, was increased in our model of EAEO, similar to other mouse models of testicular inflammation induced by viable germ cells 64 or adoptive transfer by using testis and sperm-antigen specific T cell clones 65 . An increase was detected also in testicular mRNA levels for MCP-1, a potent chemokine, involved in recruiting the immune cells to the site of inflammation.…”

Cytokines in the blood and semen of infertile patients

“…It was demonstrated that antisperm antibodies can be a common reason of male infertility also in association with the cytokine presence and that infection/inflammation of the male genital tract, systemic infection or illness may deteriorate the testicular function [ 24 ]. Conversely, secondary autoimmune orchitis can be represented by testicular vasculitis associated with systemic autoimmune diseases such as polyarteritis nodosa, Behçet's disease, and rheumatoid arthritis [ 42 , 43 ].…”

Pivotal Roles of T-Helper 17-Related Cytokines, IL-17, IL-22, and IL-23, in Inflammatory Diseases

“…Such patients have increased levels of Th17 cells, their cytokines such as IL-17A, IL-21, and IL-22, and IL-23-producing CD11c + DCs and CD68 + macrophages [137]. Moreover, because IL-17 was expressed not only in normal testis but also in higher levels in azoospermic testis, IL-17 might be involved in the maintenance of testicular immune privilege and spermatogenesis [137, 138]. In addition, pro-inflammatory cytokines including IL-1 and IL-6 have direct effects on spermatogenic cell differentiation and testicular steroidogenensis within the normal testis [139].…”