The immune-privilege of the testis causative mechanism for disturbed spermatogenesis E. coli epididymitis model, E. coli orchitis model

Transcription

1 The immune-privilege of the testis causative mechanism for disturbed spermatogenesis E. coli epididymitis model, E. coli orchitis model MIBIE Summer School Sudhanshu Bhushan 1 st August 2014

2 Aetiology of male infertility Idiopathic infertility 31,7% Varicocele 6,6% Infections (subclinical) 9,0% (Endocr), hypogonadism 8,9% Cryptorchidism 8,5% Systemic diseases 5,0% immunolog. factors 4,2% Testis tumor 2,3% Obstructions 1,5% Others 6,6% Disturbance of emission 5,8% and ejaculation (incl. erectile dysfunktion, hypospadia etc.) Nieschlag and Behre, 2000 Infection and immunological infertility: second most important cause with 13-14%

3 Epidemiology and Pathogens STDs Enterobacteriaceae No bacterial pathogen n=131 n=148 Age of patients A disease of all ages STD s preferentially in young, sexually active patients Pilatz et al., unpublished

4 Bacterial Spectrum No bacterial pathogen E. Coli Enterococcus spp. Klebsiella spp. Pseudomonas spp. S. aureus S. epidermidis Proteus spp. Morganella spp. Chlamydia trachomatis E. coli dominant pathogen Neisseria gonorrhoeae Mycoplasma spp. Pilatz et al., unpublished

5 Bacteria induced epididymo-orchitis model Bhushan et al., 2009

6 Bacterial induced epididymo-orchitis model: Mouse Caput Cauda 7d UPEC 3d UPEC Control Testis 1000x 1000x

7 Bacterial induced epididymo-orchitis model: Rat

8 UPEC CFT073 induces epididymo-orchits Ctrl UPEC

9 UPEC CFT073 induces germ cell loss in testis Ctrl testis Infected testis UPEC infected testis (Electron microscope picture) 20x 40x

10 UPEC CFT073 induces DNA break in testicular cells Ctrl UPEC

11 Pathways leading to cell death Fink et al., 2005

12 Apoptosis signaling pathways Rudel et al., 2010

13 UPEC does not induce apoptotic signaling pathways Extrinsic apoptosis Intrinsic apoptosis Pyroptosis

14 Is UPEC induces necrosis? Ctrl Raw macrophage UPEC C + - EM picture of UPEC infected testis

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16 HMGB1 translocate to the cytoplasm following infection with UPEC

17 Uropathogenic E. coli (CFT073 and 536) induces cell death in Sertoli cells and peritubular cells

18 Uropathogenic E. coli CFT073 induces cell death in Sertoli cells and peritubular cells Ctrl NPEC UPEC PTC Ctrl NPEC UEPC SC

19 Apoptosis signaling pathways Rudel et al., 2010

20 UPEC CFT073 does not induce intrinsic apoptosis pathways in Sertoli cells and peritubular cells Time (h) Caspase 6 PTC SC Time (h) Caspase 3 PTC Jurkat cell extract SC

21 UPEC does not induce enzymatic activity of Caspase 3

22 UPEC CFT073 does not induce extrinsic apoptosis pathways in Sc and PTC Time (h) Caspase-8 PTC RAW ø SC β-actin

23 DNA laddering was not observed following UPEC infection in Sertoli cells and peritubular cells M SC Ctrl UPEC M RAW ø Ctrl SNP F/T M PTC Ctrl UPEC

24 Programmed cell necrosis Kennedy et al., 2008

25 UPEC induces programmed cell necrosis in testicular cells Sertoli cells Peritubular cells Calpain activation No yes ROS production No yes ATP depletion yes yes LDH release yes yes

26 UPEC induces extracellular release of HMGB1 in in Sertoli cells and peritubular cells

27 UPEC induces extracellular release of Histone 3 in Sertoli cells Ctrl NPEC UPEC Histone 3 SC Ctrl NPEC UPEC Histone 3 PTC Ctrl NPEC UPEC HMGB1 HMGB1

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29 Danger signals released from necrotic cell could induce autoimmunity in infected testis

30 Summary Bacteria can reach testis through ascending canicular infection. UPEC infection resulted in severe impairment of spermatogenesis by germ cell loss, damage of testicular somatic cell and a decrease in sperm numbers. Necrosis appears to be the dominant cell death pathway in UPEC infected testis. Substantial necrotic changes seen in Sertoli cells will contribute to impaired spermatogenesis by loss of function in supporting the dependent germ cells.

31 Collaborations Dept. of Anatomy and Cell Biology A. Meinhardt M. Fijak V. Michel F. Áslani Y. Lu Dept. Urology & Andrology W. Weidner F. Wagenlehner H-C. Schuppe A. Pilatz K. Steger A. Paradowska-Dogan Institute of Medical Microbiology T. Chakraborty H. Hossain S Tchatalbachev E. Domann Z. Zhang Institute of Veterinary Anatomy M. Bergmann