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Genital chlamydial infections lead to severe upper reproductive tract pathology in a subset of untreated women. We demonstrated previously that TNF-α producing CD8+ T cells contribute significantly to chlamydial upper genital tract pathology in female mice. Additionally, we observed minimal chlamydial oviduct pathology develops in OT-1 transgenic (OT-1) mice, wherein CD8+ T cell repertoire is restricted to recognition of the ovalbumin peptide Ova257–264, suggesting that non-Chlamydia-specific CD8+ T cells may not be responsible for chlamydial pathogenesis. In the current study, we evaluated whether antigen-specific CD8+ T cells mediate chlamydial pathology. Groups of wild type C57BL/6J (WT), OT-1 mice, and OT-1 mice replete with WT CD8+ T cells (1×106 cells/mouse intravenously) were infected intravaginally with C. muridarum (5 × 104 IFU/mouse). Serum total anti-Chlamydia antibody and total splenic anti-Chlamydia IFN-γ and TNF-α responses were comparable among the three groups of animals. However, Chlamydia-specific IFN-γ and TNF-α production from purified splenic CD8+ T cells of OT-1 mice was minimal, whereas responses in OT-1 mice replete with WT CD8+ T cells were comparable to those in WT animals. Vaginal chlamydial clearance was comparable between the three groups of mice. Importantly, the incidence and severity of oviduct and uterine horn pathology was significantly reduced in OT-1 mice but reverted to WT levels in OT-1 mice replete with WT CD8+ T cells. Collectively, these results demonstrate that Chlamydia-specific CD8+ T cells contribute significantly to upper genital tract pathology.

H uman cytomegalovirus (HCMV), a member of the betaherpesvirus family, is the leading cause of congenital neurological complications in neonates as a result of maternal infection (1-4). Among immunocompromised patients-especially those with an organ transplant, chemotherapy, or AIDS-the reactivation of virus causes life-threatening diseases, such as gastroenteritis, encephalitis, pneumonitis, and graft rejection (5-7). In addition, HCMV infection is also implicated in widespread ocular damage and potential vision loss from retinitis, anterior uveitis, and corneal endotheliitis (8-11). Because HCMV infection of the iris is a risk factor during anterior uveitis, understanding the dynamics of viral infection at the molecular level becomes relevant for understanding the viral pathogenesis in general and developing novel strategies to prevent blindness. Therefore, we used primary cultures of human iris stromal (HIS) cells as a model to determine the susceptibility and role of 3-O-sulfated heparan sulfate (3-OS HS) during HCMV uveitis.Although HCMV entry into host cells is poorly understood (12, 13), it is clearly a multistep process that requires complex interactions between viral envelope glycoproteins and the host cell receptors (12). It has been suggested that HCMV glycoprotein B (gB) binds to heparan sulfate (HS) during viral attachment, resulting in a high virion concentration at the cell surface and further binding to the cellular receptor (14-17). This interaction has been proposed to modulate immune responses (14, 18). To date, three receptors, epidermal growth factor receptor (EGFR), platelet-derived growth factor receptor ␣ (PDGFR␣), and cellular integrins (␣2␤1, ␣6␤1, and ␣v␤3), have been implicated during HCMV entry (19)(20)(21)(22)(23)(24). In addition, recent studies have suggested the potential role of a sulfated form of HS during HCMV entry. For instance, a library of peptides derived from human hemofiltrate and screened for inhibitory effects on HCMV infection implicated the role of 6-O-sulfated HS (6-OS HS) (25) in HCMV entry. Similarly, a peptide generated against 3-OS HS using phage display library screening blocked HCMV entry (26). In addition, several sulfated polysaccharides (dextran sulfate, pentosan polysulfate, and heparin), copolymers of acrylic acid with vinyl alcohol sulfate, and 3-O-sulfated saccharide have proved to be potent inhibitors of HCMV infectivity in vitro (17,27). In this study, we investigated the susceptibility of HIS cells to HCMV infection and the role of 3-OS HS during this process. Our data demonstrate the significance of 3-OS HS during HCMV entry, and we propose a unique in vitro model for future studies related to 3-OS HS-dependent induction of proinflammatory cytokines and virus tropism.Susceptibility of primary cultures of HIS cells to HCMV infection. The HIS cultures were prepared in accordance with institutional review board-approved protocols and were isolated from anonymously donated human eyes (provided by the Illinois Eye Bank, Chicago, IL) via sterile dissecti...

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Ocular herpes simplex virus 1 (HSV-1) infection can lead to multiple complications, including iritis, an inflammation of the iris. Here, we use human iris stroma cells as a novel in vitro model to demonstrate HSV-1 entry and the inflammatory mediators that can damage the iris. The upregulated cytokines observed in this study provide a new understanding of the intrinsic immune mechanisms that can contribute to the onset of iritis. Herpes simplex virus 1 (HSV-1) is a significant ocular pathogen affecting multiple regions, including the iris (1). The iris, a specialized eye tissue, is affected in various inflammatory ophthalmic conditions (2, 3). For instance, inflammation of the iris following HSV-1 infection may be associated with elevated intraocular pressure, ultimately resulting in glaucoma, although the possibility remains that this may be steroid induced (4-6). The iris has been shown to have histopathologic involvement in HSV-1 infection of the corneal stroma, herpetic stromal keratitis (HSK) (3). Inflammation of the iris is also seen in herpetic anterior uveitis, a condition that often presents as an inflammation of the iris and ciliary body (iridocyclitis) and is the leading cause of infectious anterior uveitis worldwide (2). In addition to iris involvement in primary inflammatory conditions of various ocular tissues, there had previously been a longstanding question as to whether HSV-induced iritis could occur without concurrent or precedent keratitis. Studies performed since have indicated that HSV may cause iritis that predisposes to glaucoma without necessarily causing keratitis (6). Although these results indicate the possible pathogenesis mediated by primary HSV-1 infection of the iris, primary infection of human iris stromal (HIS) cells has not been previously investigated. Likewise, chemokine signaling, which plays a significant role in many inflammatory eye conditions (7), has been poorly studied in the context of HSV-1 infection of HIS cells. The current study demonstrates the potential of an in vitro HIS cell model to uncover the molecular basis of viral entry and the identity of the inflammatory mediators involved.HSV-1 starts its infectious journey into cells via interactions of its envelope glycoproteins with their respective host cell receptors (8). The initial attachment involves glycoprotein B (gB) and glycoprotein C (gC) interactions with host cell surface heparan sulfate proteoglycans (9, 10). HSV-1 glycoprotein D (gD), with its subsequent conformational changes, can bind to any of its host cell receptors, such as nectin-1, herpesvirus entry mediator (HVEM) (11), or 3-O-sulfated heparan sulfate (3-OS HS) (12). This conformational change is important since it allows for the gD-host cell receptor complex to associate with the heterodimer complex of glycoprotein H-glycoprotein L (gH-gL). This allows gH-gL to bind gB, a process that allows the viral and host cell membranes to fuse (12,13).Following infection by HSV-1, the intrinsic inflammatory responses contribute strongly to subsequent di...