Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2019 Apr 10;9(1):5847.
doi: 10.1038/s41598-019-42396-3.

Growth Kinetics of Chlamydia Trachomatis in Primary Human Sertoli Cells

Affiliations
Free PMC article

Growth Kinetics of Chlamydia Trachomatis in Primary Human Sertoli Cells

Simone Filardo et al. Sci Rep. .
Free PMC article

Abstract

Chlamydia trachomatis (Ct) is the leading cause of bacterial sexually transmitted infections worldwide and has been associated with male infertility. Recently, it was hypothesized that Ct may infect the epithelium of the seminiferous tubule, formed by Sertoli cells, thus leading to impaired spermatogenesis. To date, there is a lack of data on Ct infection of the seminiferous epithelium; therefore, we aimed to characterize, for the first time, an in vitro infection model of primary human Sertoli cells. We compared Ct inclusion size, morphology and growth kinetics with those in McCoy cells and we studied F-actin fibres, Vimentin-based intermediate filaments and α-tubulin microtubules in Sertoli and McCoy cells. Our main finding highlighted the ability of Ct to infect Sertoli cells, although with a unique growth profile and the inability to exit host cells. Furthermore, we observed alterations in the cytoskeletal fibres of infected Sertoli cells. Our results suggest that Ct struggles to generate a productive infection in Sertoli cells, limiting its dissemination in the host. Nevertheless, the adverse effect on the cytoskeleton supports the notion that Ct may compromise the blood-testis barrier, impairing spermatogenesis.

Conflict of interest statement

The authors declare no competing interests.

Figures

Figure 1
Figure 1
Comparison of C. trachomatis infectivity and morphological phenotype in primary human Sertoli and McCoy cells. (A) Yield of C. trachomatis D/UW-3/CX infection of primary human Sertoli and McCoy cells at a MOI = 1.0, expressed as means ± SD of four replicates from two independent experiments; (B) Phase-contrast micrographs of C. trachomatis inclusions in primary human Sertoli and McCoy cells at 24 and 48 hours post infection. Representative images of ten microscope fields are shown. Arrows point to chlamydial inclusions.
Figure 2
Figure 2
Growth kinetics of C. trachomatis in primary human Sertoli cells. Infectivity profile (A), chromosomal replication (B), quantification of the inclusion size (C) and fluorescence micrographs (D). Infected primary human Sertoli cells were removed for analysis at 4 hourly intervals and then titrated to assess the quantity of IFUs and the relative number of chlamydial genomes by qPCR. Values are expressed as means ± SD of four replicates from two independent experiments. Chlamydial inclusions were visualized by indirect immunofluorescence with species-specific anti-MOMP monoclonal antibodies (Mab6ciii). Representative images of ten chlamydial inclusion per time-point are shown. Mean and standard deviation of inclusion size, expressed as square pixels, were measured from fluorescence micrographs using ImageJ software.
Figure 3
Figure 3
Reduced cell lysis of C. trachomatis infected primary human Sertoli compared with McCoy cells. Phase contrast micrographs (A) and one-step infectivity growth profiles and chromosome replication (B) of C. trachomatis in Sertoli and McCoy cells at 24 hourly intervals up to 96 hours post infection. Values are expressed as means ± SD of four replicates from two independent experiments. Representative images of ten chlamydial inclusions per condition are shown. White arrows indicate inclusions. *cell monolayer vs culture medium p < 0.01; #cell monolayer vs culture medium p < 0.05.
Figure 4
Figure 4
Confocal analysis of cell cytoskeleton in primary human Sertoli and McCoy cells infected by C. trachomatis. Laser scanning confocal micrographs of F-actin microfilaments, Vimentin-based Intermediate Filaments and α-tubulin microtubules in primary human Sertoli (A) and McCoy (B) cells infected with C. trachomatis. Representative images of ten chlamydial inclusions are shown (100X magnification). White arrows point to assemblies of cytoskeleton fibres lining chlamydial inclusions. Green arrows point to C. trachomatis inclusions.

Similar articles

See all similar articles

Cited by 1 article

References

    1. Sessa, R., et al. Lactobacilli-lactoferrin interplay in Chlamydia trachomatis infection. Pathog Dis. 75(5), 10.1093/femspd/ftx054 (2017). - PubMed
    1. Sessa R, et al. Effect of bovine lactoferrin on Chlamydia trachomatis infection and inflammation. Biochem Cell Biol. 2017;95(1):34–40. doi: 10.1139/bcb-2016-0049. - DOI - PubMed
    1. Newman L, et al. Global Estimates of the Prevalence and Incidence of Four Curable Sexually Transmitted Infections in 2012 Based on Systematic Review and Global Reporting. PLoS One. 2015;10(12):e0143304. doi: 10.1371/journal.pone.0143304. - DOI - PMC - PubMed
    1. Bhushan S, Schuppe HC, Fijak M, Meinhardt A. Testicular infection: microorganisms, clinical implications and host-pathogen interaction. J Reprod Immunol. 2009;83(1-2):164–167. doi: 10.1016/j.jri.2009.07.007. - DOI - PubMed
    1. O’Connell CM, Ferone ME. Chlamydia trachomatis Genital Infections. Microb Cell. 2016;3(9):390–403. doi: 10.15698/mic2016.09.525. - DOI - PMC - PubMed

Publication types

Feedback