Induction of the <em>Chlamydia trachomatis</em> Persistent State by Herpes simplex Virus Type 2 Does Not Require Productive Viral Replication.

<p>Clinical and epidemiological studies have shown that multiple infection with HSV-2 and <em>Chlamydia trachomatis</em> occurs <em>in vivo</em>. We hypothesize that (i) HSV-2 co-infection of <em>C. trachomatis</em> infected cervical epithelial cells induces chlamydial persistence; (ii) productive HSV-2 replication is required for induction of persistence in <em>C. trachomatis</em>; (iii) co-infection with <em>C. trachomatis</em> and HSV-2 alters accumulation of immuno-modulatory molecules in infected cells. To test these hypotheses, a cell culture model of co-infection was established in HeLa cells. Transmission electron microscopic (TEM) analyses demonstrated aberrant chlamydial morphology in co-infected cells, which was apparent by 10 hours and prominent by 20 hours post HSV-2 infection. Moreover, co-infection reduced infectivity of progeny chlamydiae. These observations indicate chlamydial persistence and are consistent with certain historical 'markers' of persistence previously described. Since chlamydial persistence was being established, we were interested in unraveling the mechanism of induction. To determine whether HSV-2 replication was necessary, cyclohexamide (Cx), a eukaryotic protein synthesis inhibitor, was used. Cx inhibits host cell and viral protein synthesis by >95% and productive viral replication by >90%. Development of chlamydial persistence was observed in the presence of Cx. To analyze whether events during attachment and entry are sufficient for induction of chlamydial persistence, UV-inactivated, replication incompetent HSV-2 (HSV-2uv) was used. HSV-2uv is capable of attachment and entry but incapable of productive replication. Chlamydial persistence also developed during co-infection with <em>C. trachomatis</em> and HSV-2uv. Both of these observations suggest that an early event/s in HSV-2 replication, most probably occurring during HSV-2 attachment and entry, is sufficient for induction of chalmydial persistence. These observations also suggest that productive viral replication is not required for the induction of chlamydial persistence. Accumulation of chlamydial major outer membrane (MOMP) was decreased whereas pro-inflammatory chlamydial heat shock protein 60 (cHSP60) was increased in co-infected cells compared to <em>C. trachomatis</em> singly-infected cells. Among the cytokines looked at, an elevation in the levels of IL-6 was observed in HSV-2 infected and co-infected samples. Release of chlamydial antigens during chlamydial persistence increases inflammation and disease severity <em>in vivo</em>. Therefore, co-infection might increase immunopathology compared to that observed in <em>C. trachomatis</em> singly-infected individuals.</p>

Name thesis:degree_name

PhD (Doctor of Philosophy)

Level thesis:degree_level

Dissertation - restricted

Discipline thesis:degree_discipline

Biomedical Sciences

Year dc:date.issued

2005

Author dc:creator

• Deka, Srilekha

• induction
• persistence
• co-infection
• herpes
• chlamydia
• Medical Sciences
• Medicine and Health Sciences

Statement dc:rights

• Copyright by the authors.

Repository record dc:identifier

https://dc.etsu.edu/etd/1065

OAI identifier oai:identifier

oai:dc.etsu.edu:etd-2222