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Guazzone VA, Hollwegs S, Mardirosian M, Jacobo P, Hackstein H, Wygrecka M, Schneider E, Meinhardt A, Lustig L, Fijak M. Characterization of dendritic cells in testicular draining lymph nodes in a rat model of experimental autoimmune orchitis. ACTA ACUST UNITED AC 2010; 34:276-89. [DOI: 10.1111/j.1365-2605.2010.01082.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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52
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Abstract
A large body of evidence points to the existence of a close, dynamic relationship between the immune system and the male reproductive tract, which has important implications for our understanding of both systems. The testis and the male reproductive tract provide an environment that protects the otherwise highly immunogenic spermatogenic cells and sperm from immunological attack. At the same time, secretions of the testis, including androgens, influence the development and mature functions of the immune system. Activation of the immune system has negative effects on both androgen and sperm production, so that systemic or local infection and inflammation compromise male fertility. The mechanisms underlying these interactions have begun to receive the attention from reproductive biologists and immunologists that they deserve, but many crucial details remain to be uncovered. A complete picture of male reproductive tract function and its response to toxic agents is contingent upon continued exploration of these interactions and the mechanisms involved.
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Key Words
- cytokines
- immunity
- immunoregulation
- inflammation
- leydig cell
- lymphocytes
- macrophages
- nitric oxide
- prostanoids
- seminal plasma
- sertoli cell
- sperm
- spermatogenesis
- steroidogenesis
- toll-like receptors
- 16:0a-lpc, 1-palmitoyl-sn-glycero-3-phosphocholine
- 18:1a-lpc, 1-oleoyl-sn-glycero-3-phosphocholine
- 18:2a-lpc, 1-linoleoyl-sn-glycero-3-phosphocholine
- 20:4a-lpc, 1-arachidonyl-sn-glycero-3-phosphocholine
- aid, acquired immune deviation
- aire, autoimmune regulator
- ap1, activated protein 1
- apc, antigen-presenting cell
- bambi, bmp and activin membrane-bound inhibitor
- bmp, bone morphogenetic protein
- cox, cyclooxygenase
- crry, complement receptor-related protein
- ctl, cytotoxic t lymphocyte
- eao, experimental autoimmune orchitis
- eds, ethane dimethane sulfonate
- enos, endothelial nos
- fadd, fas-associated death domain protein
- fasl, fas ligand
- fsh, follicle-stimulating hormone
- gc, glucocorticoid
- hcg, human chorionic gonadotropin
- hla, human leukocyte antigen
- hmgb1, high mobility group box chromosomal protein 1
- ice, il1 converting enzyme
- ifn, interferon
- ifnar, ifnα receptor
- il, interleukin
- il1r, interleukin 1 receptor
- il1ra, il1 receptor antagonist
- inos, inducible nitric oxide synthase
- irf, interferon regulatory factor
- jak/stat, janus kinase/signal transducers and activators of transcription
- jnk, jun n-terminal kinase
- lh, luteinizing hormone
- lpc, lysoglycerophosphatidylcholine
- lps, lipopolysaccharide
- map, mitogen-activated protein
- mhc, major histocompatibility complex
- mif, macrophage migration inhibitory factor
- myd88, myeloid differentiation primary response protein 88
- nfκb, nuclear factor kappa b
- nk, cell natural killer cell
- nkt cell, natural killer t cell
- nlr, nod-like receptor
- nnos, neuronal nos
- nod, nucleotide binding oligomerization domain
- p450c17, 17α-hydroxylase/c17-c20 lyase
- p450scc, cholesterol side-chain cleavage complex
- paf, platelet-activating factor
- pamp, pathogen-associated molecular pattern
- pc, phosphocholine
- pg, prostaglandin
- pges, pge synthase
- pgi, prostacyclin
- pla2, phospholipase a2
- pmn, polymorphonuclear phagocyte
- pparγ, peroxisome proliferator-activated receptor γ
- rig, retinoic acid-inducible gene
- rlh, rig-like helicase
- ros, reactive oxygen species
- star, steroidogenic acute regulatory
- tcr, t cell receptor
- tgf, transforming growth factor
- th cell, helper t cell
- tir, toll/il1r
- tlr, toll-like receptor
- tnf, tumor necrosis factor
- tnfr, tnf receptor
- tr1, t regulatory 1
- tradd, tnfr-associated death domain protein
- traf, tumor necrosis factor receptor-associated factor
- treg, regulatory t cell
- trif, tir domain-containing adaptor protein inducing interferon β
- tx, thromboxane
- txas, thromboxane a synthase
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Abstract
The testis is an immunological privileged tissue as evidenced by its ability to support grafts with minimal rejection. Immune privilege is essential for the tolerance of neo-antigens from developing germ cells that appear after the constitution of self-tolerance, but imposes the paradoxical task of also providing efficient protection against pathogens and tumor cells. It is becoming increasingly clear that immune privilege cannot be attributed to a single factor such as the sequestration of neo-antigens from the immune system behind the blood-testis barrier, but is based on a complex multifaceted interplay between cells and factors that are essential for the reproductive function of the testis and the testicular immune system. This review summarizes the evidence that has accumulated regarding the role of Sertoli cells, androgens, and selected population of leukocytes in the maintenance of immune privilege and its perturbation in testicular inflammatory sub- and infertility.
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Histopathology of the tubuli recti at the start of experimental autoimmune orchitis in mice. Med Mol Morphol 2009; 42:230-5. [DOI: 10.1007/s00795-009-0469-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2009] [Accepted: 08/27/2009] [Indexed: 11/27/2022]
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55
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Guazzone VA, Jacobo P, Theas MS, Lustig L. Cytokines and chemokines in testicular inflammation: A brief review. Microsc Res Tech 2009; 72:620-8. [PMID: 19263422 DOI: 10.1002/jemt.20704] [Citation(s) in RCA: 143] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A wide spectrum of data in the literature shows the relevance of cytokines as paracrine regulators of spermatogenesis and steroidogenesis in the normal testis. In this brief review, we highlight the relevance of cytokines in the testis during inflammation. This phenomenon involves complex and multiple interactions among immune and germ cells generally resulting in the alteration of spermatogenesis. The complexity of these cell interactions is multiplied because Sertoli and Leydig cells are also producers of pro- and anti-inflammatory cytokines and chemokines. Also, cytokines are pleiotropic and they exert opposite and/or redundant effects in different conditions. However, in spite of this bidirectional immunoregulatory function of cytokines, the mass of the data, reported from experiments of acute testicular inflammation, shows upregulation of interleukin (IL)-1beta, IL-1alpha, IL-6, and tumor necrosis factor alpha (TNF-alpha), which induce adverse effects on germ cells. In autoimmune orchitis, a chronic testicular inflammation, chemokines such as CCL2, CCL3, and CCL4 induce attraction and extravasation of immune cells within the testicular interstitium. These cells alter the normal immunosuppressor microenvironment principally through the secretion of proinflammatory cytokines, interferon-gamma initially, and IL-6 and TNF-alpha thereafter. Germ cells expressing TNFR1, IL-6R, and Fas increase in number and undergo apoptosis, through the TNF-alpha/TNFR1, IL-6/IL-6R, and Fas/Fas L systems. The knowledge of immune-germ and somatic testicular cell interactions will contribute to the understanding of the mechanisms by which chronic inflammatory conditions of the testis can disrupt the process of spermatogenesis.
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Affiliation(s)
- Vanesa Anabella Guazzone
- Institute for Research in Reproduction, School of Medicine, University of Buenos Aires, Paraguay 2155 P10, C1121ABG Buenos Aires, Argentina
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56
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Chen Y, Wang H, Qi N, Wu H, Xiong W, Ma J, Lu Q, Han D. Functions of TAM RTKs in regulating spermatogenesis and male fertility in mice. Reproduction 2009; 138:655-66. [DOI: 10.1530/rep-09-0101] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Mice lacking TYRO3, AXL and MER (TAM) receptor tyrosine kinases (RTKs) are male sterile. The mechanism of TAM RTKs in regulating male fertility remains unknown. In this study, we analyzed in more detail the testicular phenotype of TAM triple mutant (TAM−/−) mice with an effort to understand the mechanism. We demonstrate that the three TAM RTKs cooperatively regulate male fertility, and MER appears to be more important than AXL and TYRO3. TAM−/− testes showed a progressive loss of germ cells from elongated spermatids to spermatogonia. Young adult TAM−/− mice exhibited oligo-astheno-teratozoospermia and various morphological malformations of sperm cells. As the mice aged, the germ cells were eventually depleted from the seminiferous tubules. Furthermore, we found that TAM−/− Sertoli cells have an impaired phagocytic activity and a large number of differentially expressed genes compared to wild-type controls. By contrast, the function of Leydig cells was not apparently affected by the mutation of TAM RTKs. Therefore, we conclude that the suboptimal function of Sertoli cells leads to the impaired spermatogenesis in TAM−/− mice. The results provide novel insight into the mechanism of TAM RTKs in regulating male fertility.
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O'Bryan MK, Hedger MP. Inflammatory networks in the control of spermatogenesis : chronic inflammation in an immunologically privileged tissue? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2009; 636:92-114. [PMID: 19856164 DOI: 10.1007/978-0-387-09597-4_6] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Spermatogenesis is a complex, organized process involving intimate interactions between the developing germ cells and supporting Sertoli cells. The process is also highly regulated. Studies suggest that regulation in the seminiferous epithelium involves molecules normally associated with either immune or inflammatory processes; in particular, interleukin 1a (IL1a), IL6, tumor necrosis factor (TNFa), activin A and nitric oxide (NO). While there is considerable evidence that these inflammatory mediators have effects on spermatogonial and spermatocyte development as well as critical supportive functions of the Sertoli cells, which are undoubtedly of considerable importance during testicular inflammation, there remains some skepticism regarding the significance of these molecules with respect to normal testicular function. Nonetheless, it is evident that expression of these regulators varies across the cycle of the seminiferous epithelium in a consistent manner, with major changes in production coinciding with key events within the cycle. This review summarizes the evidence supporting the hypothesis that inflammatory cytokines play a role in normal testicular spermatogenesis, as well as in the etiology of inflammation induced sub-fertility. The balance of data leads to the striking conclusion that the cycle of the seminiferous epithelium resembles a chronic inflammatory event. This appears to be a somewhat paradoxical assertion, since the testis is an immunologically privileged tissue based on its well-established ability to support grafts with minimal rejection responses. However, it may be argued that local immunoregulatory mechanisms, which confer protection from immunity on both transplanted tissues and the developing spermatogenic cells, are equally necessary to prevent local inflammation responses associated with the spermatogenic process from activating the adaptive immune response.
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Affiliation(s)
- Moira K O'Bryan
- Monash Institute of Medical Research, Monash University, Clayton, 3168, Australia.
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58
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Tokunaga Y, Terayama H, Naito M, Qu N, Hirai S, Ogawa Y, Yi SQ, Itoh M. Splenic cytokines in mice immunized with testicular germ cells. ACTA ACUST UNITED AC 2008; 31:471-6. [PMID: 17651401 DOI: 10.1111/j.1365-2605.2007.00790.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We previously established that two subcutaneous injections of viable syngeneic testicular germ cells (TGC) alone can induce CD4+ T cell-dependent experimental autoimmune orchitis (EAO) in mice. This model is histologically characterized by lymphocytic infiltration into the testes and the following aspermatogenesis. In the present study, we investigated the dynamics of splenic cytokines in EAO, using specific enzyme-linked immunosorbent assay. We found that splenic production of both type 1 helper T cell (Th1) and type 2 helper T cell (Th2)-related cytokines increased after the second but not the first immunization with TGC, indicating that secondary immune responses are critical to the EAO induction. However, the production of Th1-related cytokines became predominant at the clinical stage of EAO. Additionally, serum FSH and inhibin-B increased and decreased, respectively, during EAO. On the other hand, LH did not significantly change and testosterone temporally increased during the same period. These results indicate that both Th1- and Th2-related cytokines are involved at the pre-clinical phase of EAO, but that Th1- rather than Th2-related cytokines are responsible for the clinical phase when spermatogenesis is disrupted but the Leydig cell function is well preserved.
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Affiliation(s)
- Yo Tokunaga
- Department of Internal Medicine, Tamashima Central Hospital, Okayama, Japan
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59
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Rival C, Theas MS, Suescun MO, Jacobo P, Guazzone V, van Rooijen N, Lustig L. Functional and phenotypic characteristics of testicular macrophages in experimental autoimmune orchitis. J Pathol 2008; 215:108-17. [PMID: 18381617 DOI: 10.1002/path.2328] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Testicular inflammation with compromised fertility can occur despite the fact that the testis is considered an immunoprivileged organ. Testicular macrophages have been described as cells with an immunosuppressor profile, thus contributing to the immunoprivilege of the testis. Experimental autoimmune orchitis (EAO) is a model of organ-specific autoimmunity and testicular inflammation. EAO is characterized by an interstitial inflammatory mononuclear cell infiltration, damage of the seminiferous tubules and germ cell apoptosis. Here we studied the phenotype and functions of testicular macrophages during the development of EAO. By stereological analysis, we detected an increased number of resident (ED2+) and non-resident (ED1+) macrophages in the testicular interstitium of rats with orchitis. We showed that this increase was mainly due to monocyte recruitment. The in vivo administration of liposomes containing clodronate in rats undergoing EAO led to a reduction in the number of testicular macrophages, which correlated with a decreased incidence and severity of the testicular damage and suggests a pathogenic role of macrophages in EAO. By immunohistochemistry and flow cytometry we detected an increased number of testicular macrophages expressing MHC class II, CD80 and CD86 costimulatory molecules in rats with orchitis. Also, testicular macrophages from rats with EAO showed a higher production of IFNgamma (ELISA). We conclude that testicular macrophages participate in EAO development, and the ED1+ macrophage subset is the main pathogenic subpopulation. They stimulate the immune response through the production of pro-inflammatory cytokines and antigen presentation and thus activation of T cells in the target organ.
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Affiliation(s)
- C Rival
- Centro de Investigaciones en Reproducción, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
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60
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Theas MS, Rival C, Jarazo-Dietrich S, Jacobo P, Guazzone VA, Lustig L. Tumour necrosis factor-alpha released by testicular macrophages induces apoptosis of germ cells in autoimmune orchitis. Hum Reprod 2008; 23:1865-72. [PMID: 18579514 DOI: 10.1093/humrep/den240] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Experimental autoimmune orchitis (EAO) is a model of chronic inflammation and infertility useful for studying testicular immune and germ cell (GC) interactions. In this model, EAO was induced in rats by immunization with testicular homogenate and adjuvants; Control (C) rats were injected with adjuvants. EAO was characterized by an interstitial infiltrate of lymphomonocytes and seminiferous tubule damage, moderate 50 days (focal orchitis) and severe 80 days after the first immunization (severe orchitis). Based on the previous results showing that the number of macrophages and apoptotic GC expressing tumour necrosis factor (TNF) receptor 1 increased in EAO, we studied the role of macrophages and TNF-alpha in GC apoptosis. METHODS AND RESULTS Conditioned media of testicular macrophages (CMTM) obtained from rats killed on Days 50 and 80 decreased the viability (MTS, P < 0.01) and induced apoptosis (terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labelling, TUNEL) of GC obtained from EAO but not from non-immunized, N rats (P < 0.001). TNF-alpha content (enzyme-linked immunosorbent assay) was significantly higher in the CMTM from EAO versus C rats on Day 80 (P < 0.05). The apoptotic effect of CMTM from Day 80 rats was abrogated by a selective TNF-alpha blocker (Etanercept). Moreover, TNF-alpha in vitro induced GC apoptosis. TNF-alpha expression (by immunofluorescence) was observed in testicular (ED2(+)) and non-resident (ED1(+)) macrophages, the percentage of TNF-alpha(+) macrophages being similar in focal and severe orchitis. CONCLUSIONS Results demonstrated that soluble factors released from testicular EAO macrophages induce apoptosis of GC, biased by the local inflammatory environment, and that TNF-alpha is a relevant cytokine involved in testicular damage during severe orchitis.
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Affiliation(s)
- M S Theas
- Instituto de Investigaciones en Reproducción, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, Piso 10, C1121 ABG Buenos Aires, Argentina.
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61
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Abstract
The production, differentiation, and presence of male gametes represent inimitable challenges to the immune system, as they are unique to the body and appear long after the maturation of the immune system and formation of systemic self-tolerance. Known to protect germ cells and foreign tissue grafts from autoimmune attack, the 'immune privilege' of the testis was originally, and somewhat simplistically, attributed to the existence of the blood-testis barrier. Recent research has shown a previously unknown level of complexity with a multitude of factors, both physical and immunological, necessary for the establishment and maintenance of the immunotolerance in the testis. Besides the blood-testis barrier and a diminished capability of the large testicular resident macrophage population to mount an inflammatory response, it is the constitutive expression of anti-inflammatory cytokines in the testis by immune and particularly somatic cells, that represents an essential element for local immunosuppression. The role of androgens in testicular immune regulation has long been underestimated; yet, accumulating evidence now shows that they orchestrate the inhibition of proinflammatory cytokine expression and shift cytokine balance toward a tolerogenic environment. Furthermore, the role of the testicular dendritic cells in suppressing antigen-specific immunity and T-lymphocyte activation is discussed. Finally, the active role mast cells play in the induction and amplification of immune responses, both in infertile humans and in experimental models, highlights the importance of preventing mast cell activation to maintain the immune-privileged status of the testis.
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Affiliation(s)
- Monika Fijak
- Department of Anatomy and Cell Biology, Justus-Liebig-University of Giessen, Giessen, Germany
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62
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Rodriguez MG, Rival C, Theas MS, Lustig L. Immunohistopathology of the contralateral testis of rats undergoing experimental torsion of the spermatic cord. Asian J Androl 2006; 8:576-83. [PMID: 16847529 DOI: 10.1111/j.1745-7262.2006.00146.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
AIM To evaluate the immunohistopathological changes in the contralateral testis of rats after an experimental spermatic cord torsion. METHODS Male Sprague-Dawley rats of 45-50 days old were subjected to a 720 degree unilateral spermatic cord torsion for 10, 30 and 80 days (experimental group, E), respectively or sham operation (control group, C). Histopathology of the contralateral testis as well as germ cell apoptosis were studied using the Terminal Deoxynucleotidyl Transferase Biotin-dUTP Nick End Labeling (TUNEL) technique. The number of testicular lymphocytes, mast cells and macrophages, and the expression of tumor necrosis factor-alpha (TNF-alpha) and its receptor (TNFR1) in testicular cells of the contralateral testis were quantified by histochemistry and immunohistochemistry. TNF-alpha concentration in testicular fluid was determined by ELISA. RESULTS In the contralateral testis of rats from the E group, the maximal degree of damage of the germinal epithelium was seen 30 days after torsion. At this time we observed in the E group vs. the C group increases: (i) the number of testicular T-lymphocytes; (ii) the number of testicular mast cells and macrophages; (iii) the percentage of macrophages expressing TNF-alpha; (iv) TNF-a concentration in testicular fluid; (v) the number of apoptotic germ cells; and (vi) the number of TNFR1+ germ cells. CONCLUSION Experimental spermatic cord torsion induces, in the contralateral testis, a focal damage of seminiferous tubules characterized by apoptosis and sloughing of germ cells. Results suggest humoral and cellular immune mediated testicular cell damage in which macrophages and mast cells seem to be involved in the induction of germ cell apoptosis through the TNF-alpha/TNFR1 system and in the modulation of the inflammatory process.
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Affiliation(s)
- Marcelo G Rodriguez
- Center for Research in Reproduction, School of Medicine, University of Buenos Aires, Buenos Aires C1121 ABG, Argentina
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63
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Rival C, Theas MS, Guazzone VA, Lustig L. Interleukin-6 and IL-6 receptor cell expression in testis of rats with autoimmune orchitis. J Reprod Immunol 2006; 70:43-58. [PMID: 16458979 DOI: 10.1016/j.jri.2005.10.006] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2005] [Revised: 08/30/2005] [Accepted: 10/18/2005] [Indexed: 01/24/2023]
Abstract
Experimental autoimmune orchitis (EAO) is an organ-specific model of autoimmunity characterized by an interstitial lymphomononuclear cell infiltrate as well as sloughing and apoptosis of germ cells. EAO was induced in adult male Sprague-Dawley rats by active immunization with testicular homogenate and adjuvants. Rats injected with saline solution and adjuvants were used as control group. The aim of this work was to study the expression of interleukin-6 (IL-6) and its receptor (IL-6R) in the testis of rats with EAO and analyze whether IL-6 could be involved in germ cell apoptosis. By immunohistochemistry, we detected IL-6 expression in testicular macrophages and Leydig cells of control and EAO rats. Sertoli cells showed IL-6 immunoreactivity in most of the seminiferous tubules of control rats, while a few IL-6+ Sertoli cells were found in the testis of rats with EAO. IL-6R immunoreactivity was observed in macrophages, Leydig and germ cells. A significant increase was noted in the number of IL-6R+ germ cells in rats with EAO compared to control rats. The content of IL-6 (ELISA) in the conditioned media obtained from testicular macrophages of rats with orchitis was significantly higher than in the control group. By immunofluorescence performed on isolated testicular macrophages, IL-6 was shown to be expressed by monocytes recently arrived from circulation (ED1+ cells), while resident macrophages (ED2+ cells) were negative. In vitro experiments (trypan blue and MTS assays) showed that IL-6 (50 ng/ml) reduced germ cell viability. We demonstrated also using the TUNEL technique that IL-6 added to cultures of seminiferous tubule segments induced apoptosis of germ cells. Our results suggest that IL-6 and IL-6R may be involved in the pathogenesis of autoimmune orchitis by promoting testicular inflammation and germ cell apoptosis.
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Affiliation(s)
- Claudia Rival
- Centro de Investigaciones en Reproducción, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, Piso 10, C1121 ABG Buenos Aires, Argentina.
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Theas MS, Rival C, Dietrich SJ, Guazzone VA, Lustig L. Death receptor and mitochondrial pathways are involved in germ cell apoptosis in an experimental model of autoimmune orchitis. Hum Reprod 2006; 21:1734-42. [PMID: 16585127 DOI: 10.1093/humrep/del066] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Studies on experimental autoimmune orchitis (EAO) have helped to elucidate immunological mechanisms involved in testicular damage. We previously demonstrated that EAO is characterized by lymphomononuclear cell infiltrates and apoptosis of spermatocytes and spermatids expressing Fas and TNFR1. The aim of this work was to characterize the pathways involved in germ cell apoptosis in EAO and to determine the involvement of the Bcl-2 protein family in this process. METHODS AND RESULTS EAO was induced in rats by immunization with testicular homogenate (TH) and adjuvants, whereas control (C) rats were injected with saline solution and adjuvants. Testis of EAO rats showed procaspase 8 cleavage products (western blot) with high caspase 8 activity. Cytochrome c content increased in the cytosol and decreased in the mitochondrial fraction of testis from EAO rats compared with C, concomitant with increased caspase 9 activity. Bax was mainly expressed in spermatocytes and spermatids and Bcl-2 in basal germ cells (immunohistochemistry). Baxbeta isoform content increased in EAO rat testis compared with C, whereas content of Baxalpha remained unchanged (western blot). However, Baxalpha content decreased in the cytosol and increased in the mitochondrial and endoplasmic reticulum (ER)-enriched fractions of testis from EAO rats compared with C (western blot). Bcl-2 content also increased in the testes of EAO rats. CONCLUSIONS Our results demonstrated that extrinsic, mitochondrial and possibly ER pathways are inducers of germ cell apoptosis in EAO and that Bax and Bcl-2 proteins modulate this process.
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Affiliation(s)
- M S Theas
- Centro de Investigaciones en Reproducción, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
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Li X, Strauss L, Kaatrasalo A, Mayerhofer A, Huhtaniemi I, Santti R, Mäkelä S, Poutanen M. Transgenic mice expressing p450 aromatase as a model for male infertility associated with chronic inflammation in the testis. Endocrinology 2006; 147:1271-7. [PMID: 16306085 DOI: 10.1210/en.2005-0654] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Our previous studies have shown that transgenic male mice expressing human P450 aromatase (AROM+) are infertile. In the present study, we followed the testis phenotype up to 15 months of age in these mice. The testes of the old AROM+ mice showed Leydig cell hypertrophy and hyperplasia, as indicated by the staining for steroidogenic enzymes and androgen and estrogen receptors. However, the Leydig cell adenomas did not show signs of malignization. In contrast, we observed a marked increase in the number of activated macrophages in the testicular interstitium of the aging AROM+ mice. The macrophages were further shown to express high levels of CD68 (a monocyte/macrophage marker) and secrete TNFalpha, indicating strong activation, presumably by estrogen exposure. The increased activity of the macrophages was associated with Leydig cell depletion (analyzed at the age of 9 and 15 months) and an increased number of mast cells and fibrosis in the testicular interstitium. Interestingly, similar findings have been made in testes of infertile men. Hence, the aging AROM+ males present with a phenocopy of inflammation-associated infertility in men, providing a model for further studies on the putative link among estrogens, orchitis, and infertility.
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Affiliation(s)
- Xiangdong Li
- Department of Physiology, Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FIN-20520 Turku, Finland
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66
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Affiliation(s)
- C Rival
- Center for Research in Reproduction, School of Medicine, University of Buenos Aires, Argentina
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67
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Rival C, Lustig L, Iosub R, Guazzone VA, Schneider E, Meinhardt A, Fijak M. Identification of a dendritic cell population in normal testis and in chronically inflamed testis of rats with autoimmune orchitis. Cell Tissue Res 2006; 324:311-8. [PMID: 16432710 DOI: 10.1007/s00441-005-0129-5] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2005] [Accepted: 11/13/2005] [Indexed: 10/25/2022]
Abstract
Experimental autoimmune orchitis (EAO) in the rat is the primary chronic animal model for the investigation of one of the main causes of male infertility, viz., testicular inflammation. Dendritic cells (DC) are potent antigen-presenting cells that play a fundamental role in autoimmune disease. We investigated the number of DC in normal testis and examined whether DC infiltrated the testis during the development of EAO. EAO was induced by active immunization with testis homogenate and adjuvants in two strains of rat (Wistar and Sprague Dawley). The presence of DC in testis was determined, 50 and 80 days after the first immunization, by immunohistochemical staining with specific antibodies (OX-62 and CD11c), and then the total number of DC was measured by stereological analysis. Labeled cells were found only in the interstitial compartment and within granulomas of EAO animals. The number of DC in EAO testes increased compared with control rats in both strains, whereas the number of OX-62+ and CD11c+ cells in adjuvant controls remained unchanged compared with untreated rats. Interspecies variations in the quantity of DC were found, with the total number of DC per testis in untreated and adjuvant control Sprague-Dawley rats being about three times higher than that seen in Wistar rats. Moreover, the increase in DC numbers at 80 days was less prominent in EAO testes of Sprague-Dawley rats than in the Wistar strain in which EAO was more severe and showed a higher number of granulomae. Thus, we have identified the DC population in normal and chronically inflamed testis. The increase in DC observed in EAO suggests that, under inflammatory conditions, the modified action(s) of these cells is a factor in the induction of the autoimmune response in testis.
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Affiliation(s)
- Claudia Rival
- Center for Research in Reproduction, University of Buenos Aires, Buenos Aires, Argentina
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Itoh M, Terayama H, Naito M, Ogawa Y, Tainosho S. Tissue microcircumstances for leukocytic infiltration into the testis and epididymis in mice. J Reprod Immunol 2005; 67:57-67. [PMID: 16111766 DOI: 10.1016/j.jri.2005.06.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Spermatozoa do not appear in the seminiferous epithelium until puberty, when immune tolerance has already been established. Therefore, they contain various autoimmunogenic materials which are recognized as foreign by the self immune system. However, the testis and epididymis are known as immunologically privileged organs. In particular, the blood-testis barrier (BTB) formed by Sertoli cells and the blood-epididymal barrier formed by epididymal epithelial cells protect autoimmunogeneic spermatozoa from attack by the self immune system. The immune privileged circumstances in the testis and epididymis have been demonstrated by many studies to involve a local transplantation system. We review here the immune privileged status of these organs from the viewpoint of induction of inflammatory cell responses in mice. The testicular interstitium in mice is resistant to vasculitis, lymphangitis, spermatic granuloma and polymorphonuclear cell infiltration: however, the epididymal interstitium is vulnerable to them. Therefore, the testicular tissue outside BTB is also protected from inflammatory cell infiltration, although many resident macrophages are normally present in the testis. In sharp contrast, subcutaneous injection of viable syngeneic testicular germ cells (TGC) alone induces autoimmune orchitis with no involvement of the epididymitis in mice. In the testes of TGC-immunized animals, severe lymphocytic infiltration with aspermatogenesis was seen in spite of no use of adjuvants. Unexpectedly, injections of viable epididymal spermatozoa (ES) did not evoke any autoimmune inflammation in the epididymides. Therefore, the testis rather than the epididymis may easily become an unprivileged organ as to autoimmunity under some special conditions.
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Affiliation(s)
- Masahiro Itoh
- Department of Anatomy, Tokyo Medical University, Shinjuku 6-1-1, Shinjuku, Tokyo 160-8402, Japan.
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Guazzone VA, Denduchis B, Lustig L. Involvement of CD44 in leukocyte recruitment to the rat testis in experimental autoimmune orchitis. Reproduction 2005; 129:603-9. [PMID: 15855623 DOI: 10.1530/rep.1.00329] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Experimental autoimmune orchitis (EAO) is characterized by an interstitial mononuclear cell infiltrate and a severe lesion of the seminiferous tubules with germ cells that undergo apoptosis and sloughing. The aim of this study was to determine the role of CD44 in testicular leukocyte recruitment in EAO. The biological functions of CD44 have been attributed to the generation of a functionally active hyaluronan-binding phenotype. Orchitis was induced in Sprague-Dawley adult rats by active immunization with an emulsion of testicular homogenate and complete Freund's adjuvant using Bordetella pertussis as co-adjuvant. Control rats (C) injected with saline and adjuvants and normal (N) untreated rats were also studied. CD44 expression was analyzed by flow cytometry in peripheral blood mononuclear cells (PBMC) and lymph node cells isolated from rats at different times after the first immunization. We observed an increase in the mean fluorescence intensity of both samples in the C and experimental (E) groups only after the immunization period. A significant decrease in percentage of CD44+PBMC and in mean fluorescence intensity was observed in rats with orchitis compared with the C group. By in vitro hyaluronic acid-binding assay we demonstrated that the percentage of PBMC adhesion was higher in the E group compared with the C and N groups. By immunohistochemistry, we observed a significant increase in the number of CD44+cells in the testicular interstitium of rats with severe orchitis compared with the N and C groups. These results suggested that the CD44 molecule is involved in the homing of lymphomonocytes into the testes of rats with autoimmune orchitis.
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Affiliation(s)
- V A Guazzone
- Centro de Investigaciones en Reproducción, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155 piso 10, C1121 ABG, Buenos Aires, Argentina.
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Lysiak JJ. The role of tumor necrosis factor-alpha and interleukin-1 in the mammalian testis and their involvement in testicular torsion and autoimmune orchitis. Reprod Biol Endocrinol 2004; 2:9. [PMID: 15012831 PMCID: PMC404472 DOI: 10.1186/1477-7827-2-9] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2003] [Accepted: 03/10/2004] [Indexed: 12/04/2022] Open
Abstract
This review will focus the roles of TNF-alpha, IL-1 alpha, and IL-1 beta in the mammalian testis and in two testicular pathologies, testicular torsion and orchitis. TNF alpha in the testis is produced by round spermatids, pachytene spermatocytes, and testicular macrophages. The type 1 TNF receptor has been found on Sertoli and Leydig cells and numerous studies suggest a paracrine mode of action for TNF alpha in the normal testis. IL-1 alpha has been reported to be produced by Sertoli cells, testicular macrophages, and possibly postmeiotic germ cells. IL-1 receptors have been reported on Sertoli cells, Leydig cells, testicular macrophages, and germ cells suggesting both autocrine and paracrine functions. While these proinflammatory cytokines have important roles in normal testicular homeostasis, an elevation of their expression can lead to testicular dysfunctions. Testicular torsion is a clinical pathology with results in testicular ischemia and surgical intervention is often required for reperfusion. A pivotal role for IL-1beta in the pathology of testicular torsion has been recently described whereby an increase in IL-1beta production after reperfusion of the testis is correlated with the activation of the stress-related kinase, c-jun N-terminal kinase, and ultimately resulting in neutrophil recruitment to the testis and germ cell apoptosis. In autoimmune orchitis, on the other hand, TNF alpha produced by T-lymphocytes and macrophages of the testis has been implicated in the development and progression of the disease. Thus, both proinflammatory cytokines, TNF alpha and IL-1, have significant roles in normal testicular functions as well as in certain testicular pathologies.
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Affiliation(s)
- Jeffrey J Lysiak
- Department of Urology, University of Virginia, Charlottesville, VA 22908, USA.
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Guazzone VA, Rival C, Denduchis B, Lustig L. Monocyte chemoattractant protein-1 (MCP-1/CCL2) in experimental autoimmune orchitis. J Reprod Immunol 2003; 60:143-57. [PMID: 14638441 DOI: 10.1016/j.jri.2003.08.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Experimental autoimmune orchitis (EAO) is characterized by an interstitial mononuclear cell infiltrate and a severe lesion of seminiferous tubules with germ cells that undergo apoptosis and sloughing. The mechanism by which immune cells migrate and extravasate in the testicular interstitium is poorly understood. The aim of this study was to detect the variations in the expression of monocyte chemoattractant protein-1 (MCP-1/CCL2) and its receptor in the testis of rats undergoing autoimmune orchitis. EAO was induced in Sprague-Dawley adult rats by active immunization with an emulsion of testicular homogenate and complete Freund adjuvant using Bordetella pertussis as co-adjuvant. Control rats injected with saline and adjuvants and normal untreated rats were also studied. By ELISA we observed a significant increase of MCP-1 in the testicular fluid (TF) and in the conditioned medium obtained from cultures of testicular macrophages of rats with EAO compared with control groups. By immunohistochemistry, an increase in MCP-1 expression was observed in mononuclear, endothelial, Leydig and peritubular cells. MCP-1 immunoreactivity was also detected in Sertoli cell cytoplasm of rats with severe orchitis. A 2-fold increase in the number of mononuclear cells that express CCR2 was also found in rats with orchitis compared with controls. In conclusion, we demonstrated in vivo that MCP-1 is highly expressed in testicular interstitial cells suggesting that this chemokine has an important role in recruiting immune cells to the testis in rats undergoing autoimmune orchitis.
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Affiliation(s)
- Vanesa A Guazzone
- Centro de Investigaciones en Reproducción, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155 piso 10, C1121 ABG, Buenos Aires, Argentina.
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