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R N Lausch

Publications and source records attributed to R N Lausch.

At least 19 recordsLinked to original sources
PubMed2005

A novel role for neutrophils as a source of T cell-recruiting chemokines IP-10 and Mig during the DTH response to HSV-1 antigen.

Analogous to CD4+ T cells, neutrophils are essential participants in delayed-type hypersensitivity (DTH) to Herpes simplex virus type 1 antigen. However, what role they play in this cellular immune response is unclear. The recent recognition that neutrophils are potent producers of chemokines led us to hypothesize that they may help recruit CD4+ effector T cells. In the present study, we show that neutrophil depletion was accompanied by a marked decrease in the numbers of CD4+ and CXC receptor 3+ (CXCR3+)-expressing cells migrating to the DTH site and a sharp drop in the levels of interferon-inducible protein 10 (IP-10) and monokine induced by IFN-gamma (Mig). Purified mouse neutrophils were stimulated directly by IFN-gamma to secrete these chemokines, and neutrophils at the DTH site expressed IP-10. IFN-gamma knockout mice, which manifested depressed ear-swelling following DTH challenge, made little IP-10 and no Mig. Reconstitution of these mice with IFN-gamma induced CXCR3 ligand synthesis. Depletion of neutrophils or CD4+ T cells but not CD8+ T cells markedly reduced IFN-gamma levels, suggesting the former were direct (or indirect) cellular sources of this cytokine. Collectively, our results support the hypothesis that neutrophil production of T cell-recruiting chemokines contributes to the regulation and amplification of the DTH response.

Animals↗
PubMed2004

Acute ventilator-induced vascular permeability and cytokine responses in isolated and in situ mouse lungs.

To determine the influence of experimental model and strain differences on the relationship of vascular permeability to inflammatory cytokine production after high peak inflation pressure (PIP) ventilation, we used isolated perfused mouse lung and intact mouse preparations of Balb/c and B6/129 mice ventilated at high and low PIP. Filtration coefficients in isolated lungs and bronchoalveolar lavage (BAL) albumin in intact mice increased within 20-30 min after initiation of high PIP in isolated Balb/c lungs and intact Balb/c, B6/129 wild-type, and p55 and p75 tumor necrosis factor (TNF) dual-receptor null mice. In contrast, the cytokine response was delayed and variable compared with the permeability response. In isolated Balb/c lungs ventilated with 25-27 cmH(2)O PIP, TNF-alpha, interleukin (IL)-1 beta, IL-1 alpha, macrophage inflammatory protein (MIP)-2, and IL-6 concentrations in perfusate were markedly increased in perfusate at 2 and 4 h, but only MIP-2 was detectable in intact Balb/c mice using the same PIP. In intact wild-type and TNF dual-receptor null mice with ventilation at 45 cmH(2)O PIP, the MIP-2 and IL-6 levels in BAL were significantly increased after 2 h in both groups, but there were no differences between groups in the BAL albumin and cytokine concentrations or in lung wet-to-dry weight ratios. TNF-alpha was not be detected in BAL fluids in any group of intact mice. These results suggest that the alveolar hyperpermeability induced by high PIP ventilation occurs very rapidly and is initially independent of TNF-alpha participation and unlikely to depend on MIP-2 or IL-6.

Acute Disease↗
PubMed2001

Autocrine action of IL-10 suppresses proinflammatory mediators and inflammation in the HSV-1-infected cornea.

We investigated whether IL-10 produced endogenously would influence the development of HSV-1-induced acute corneal disease. Murine corneal epithelial cells and fibroblasts cultured in vitro expressed IL-10 mRNA and protein constitutively and also IL-10 receptors. Inclusion of IL-10 neutralizing antibody in the culture medium significantly (p<0.05) enhanced TNF-alpha-induced IL-6 and MIP-2 production by both corneal cell types. Endogenous IL-10 synthesis, which also occurred in vivo, was not modulated by Herpes virus infection or by depletion of neutrophils or natural killer cells. Antibody to IL-10 given locally at the time of HSV-1 intracorneal infection was associated with significantly (p<0.05) enhanced production of IL-6, MIP-2, and MIP-1alpha, increased neutrophil infiltration, and more extensive corneal disease. Similarly, mice with a disrupted IL-10 gene developed more severe corneal disease than wild-type controls. Collectively, these observations suggest that locally produced IL-10 can act in an autocrine/paracrine fashion to down-regulate the production of proinflammatory mediators and thus limit corneal inflammation.

Animals↗
PubMed2001

Synthesis of type II interleukin-1 receptors by human corneal epithelial cells but not by keratocytes.

PURPOSE: The purpose of this study was to determine whether human corneal epithelial cells and keratocytes synthesize both the soluble and membrane forms of the type II IL-1 receptor (IL-1RII). METHODS: Primary cell cultures of human corneal epithelial cells and keratocytes were established from human corneas. RT-PCR was used to analyze cell cultures for expression of IL-1RII mRNA. The capacity of corneal cells to synthesize membrane-bound IL-1RII was determined by immunofluorescence microscopy, whereas ELISA was used to quantitate synthesis of soluble IL-1RII after IL-1alpha and TNF-alpha stimulation. RESULTS: Corneal epithelial cells expressed IL-1RII mRNA. The cells also stained positive for membrane-bound IL-1RII, and media harvested from epithelial cell cultures contained up to 50 pg/ml of soluble IL-1RII. Both IL-1alpha and TNF-alpha significantly enhanced the amounts of soluble IL-1RII released from epithelial cell surfaces. In contrast to epithelial cells, corneal keratocytes did not express IL-1RII mRNA. Membrane-bound IL-1RII was not detected on keratocytes, nor was soluble IL-1RII detected in culture media harvested from these cells. CONCLUSIONS: Human corneal epithelial cells but not corneal keratocytes synthesize both membrane and soluble forms of IL-1RII. Because both forms of IL-1RII can function as IL-1alpha antagonists, the results suggest that human corneal epithelial cells but not corneal keratocytes have evolved the capacity to dampen IL-1alpha responses through the production of IL-1RII.

Cells, Cultured↗
PubMed2000

Calcitonin gene-related peptide induces IL-8 synthesis in human corneal epithelial cells.

Calcitonin gene-related peptide (CGRP), a neuropeptide with proinflammatory activities, is released from termini of corneal sensory neurons in response to pain stimuli. Because neutrophil infiltration of the clear corneal surface is a hallmark of corneal inflammation in the human eye, we determined whether CGRP can bind to human corneal epithelial cells (HCEC) and induce expression of the neutrophil chemotactic protein IL-8. It was found that HCEC specifically bound CGRP in a saturable manner with a Kd of 2.0 x 10-9 M. Exposure of HCEC to CGRP induced a significant increase in intracellular cAMP levels and enhanced IL-8 synthesis nearly 4-fold. The capacity of CGRP to stimulate cAMP and IL-8 synthesis was abrogated in the presence of the CGRP receptor antagonist CGRP8-37. CGRP stimulation had no effect on the half-life of IL-8 mRNA while increasing IL-8 pre-mRNA synthesis >2-fold. In contrast to IL-8, CGRP did not induce monocyte chemotactic protein-1 or RANTES synthesis, nor did the neuropeptide enhance detectable increases in steady state levels of mRNA specific for these two beta-chemokines. The results suggest that HCEC possess CGRP receptors capable of initiating a signal transduction cascade that differentially activates expression of the IL-8 gene but not the genes for monocyte chemotactic protein-1 or RANTES. The capacity of CGRP to stimulate IL-8 synthesis in HCEC suggests that sensory neurons are involved in induction of acute inflammation at the eye surface.

Calcitonin Gene-Related Peptide↗
PubMed2000

Role of macrophages in restricting herpes simplex virus type 1 growth after ocular infection.

PURPOSE: To investigate the role macrophages play in controlling herpes simplex virus (HSV)-1 replication after infection of the murine cornea. METHODS: Macrophage depletion in selected tissues before or after virus infection was achieved by repeated subconjunctival (SCJ) and/or intravenous (IV) injection of liposomes containing dichloromethylene diphosphonate (L-Cl2MDP). Controls received liposomes containing phosphate-buffered saline (L-PBS). The efficiency of depletion was evaluated by histologic examination. Virus content in infected tissues was determined by standard plaque assay. Delayed-type hypersensitivity (DTH) responsiveness was assessed using the ear-swelling assay. Antibody isotype responses to virus antigens and cytokine production were monitored by enzyme-linked immunosorbent assay. RESULTS: Balb/c mice given SCJ injection of L-Cl2MDP 4 and 2 days before HSV-1 corneal infection were found to have ocular virus titers as much as 10(5)-fold higher than that seen in the L-PBS-treated controls 8 days after infection. When L-Cl2MDP treatment was delayed until 2 and 4 days after infection, virus titers in the eye were analogous to those in the control animals. Subconjunctival and submandibular lymph node macrophages in mice given local (SCJ) L-Cl2MDP pretreatment were profoundly reduced, whereas the number of corneal Langerhans' cells and lymph node dendritic cells remained unchanged. Local L-Cl2MDP pretreatment was associated with significantly reduced DTH responsiveness to HSV-1 antigen, and an alteration in selected antibody isotype production. Depletion of macrophages in the subconjunctival tissue before corneal infection was not accompanied by enhanced virus growth at early times (2 or 4 days) after infection. CONCLUSIONS: Macrophages play an important role in restricting HSV-1 growth after corneal infection. These cells appear to be required for the development of an acquired immune response, presumably by functioning in antigen processing and presentation. The hypothesis that macrophages are major participants in innate immunity to HSV-1 corneal infection was not supported.

Acid Phosphatase↗
PubMed2000

Substance P differentially stimulates IL-8 synthesis in human corneal epithelial cells.

PURPOSE: To determine whether substance P (SP), a neuropeptide with proinflammatory properties, specifically interacts with human corneal epithelial cells to stimulate synthesis of the chemokines interleukin (IL)-8, monocyte chemo-attractant protein (MCP)-1, and regulated on activation normal T-cell expressed and secreted (RANTES) protein. METHODS: Primary cultures of human corneal epithelial cells were established from human corneas. Expression of the SP receptor neurokinin (NK)-1 was determined by both the reverse transcription-polymerase chain reaction (RT-PCR) and radiolabeled saturation binding experiments. Synthesis of chemokine-specific RNA in cells stimulated with SP was analyzed by RT-PCR, and quantitation of chemokine protein synthesis was achieved by enzyme-linked immunosorbent assay. RESULTS: Human corneal epithelial cells expressed NK-1 mRNA and bound SP with a K:(d) characteristic of NK-1. Exposure of cells to SP had no effect on IL-8-specific mRNA synthesis, whereas it increased the half-life of IL-8 transcripts by more than twofold, resulting in significant enhancement of IL-8 synthesis. The capacity of SP to bind to corneal epithelial cells and to induce IL-8 synthesis was abrogated in the presence of a specific NK-1 receptor antagonist. In contrast to IL-8, exposure of cells to SP did not stimulate synthesis of MCP-1 or RANTES. CONCLUSIONS: The results suggest that human corneal cells express NK-1 receptors that specifically bind SP and induce IL-8 synthesis by stabilizing the chemokine's transcripts.

Cells, Cultured↗
PubMed1999

Human corneal cells and other fibroblasts can stimulate the appearance of herpes simplex virus from quiescently infected PC12 cells.

A two-cell system for the stimulation of herpes simplex virus type 1 (HSV-1) from an in vitro model of long-term (quiescent) infection is described. Rat pheochromocytoma (PC12) cells differentiated with nerve growth factor were infected with HSV-1 strain 17. Little, if any, cytotoxicity was observed, and a quiescent infection was established. The long-term infection was characterized by the absence of all detectable virus in the culture medium and little, if any, detectable early or late viral-gene expression as determined by reverse transcriptase PCR analysis. The presence of HSV-1 DNA was determined by PCR analysis. This showed that approximately 180 viral genomes were present in limiting dilutions where as few as 16 cells were examined. The viral DNA was infectious, since cocultivation with human corneal fibroblasts (HCF) or human corneal epithelial cells (HCE) resulted in recovery of virus from most, if not all, clusters of PC12 cells. Following cocultivation, viral antigens appeared first on PC12 cells and then on neighboring inducing cells, as determined by immunofluorescent staining, demonstrating that de novo viral protein synthesis first occurred in the long-term-infected PC12 cells. Interestingly, the ability to induce HSV varied among the cell lines tested. For example, monkey kidney CV-1 cells and human hepatoblastoma HepG2 cells, but not mouse neuroblastoma cells or undifferentiated PC12 cells, mediated stimulation. This work thus shows that (i) quiescent HSV infections can be maintained in PC12 cells in vitro, (ii) HSV can be induced from cells which do not accumulate significant levels of latency-associated transcripts, and (iii) the activation of HSV gene expression can be induced via neighboring cells. The ability of adjacent cells to stimulate HSV gene expression in neuron-like cells represents a novel area of study. The mechanism(s) whereby HCF, HCE, and HepG2 and CV-1 cells communicate with PC12 cells and stimulate viral replication, as well as how this system compares with other in vitro models of long-term infection, is discussed.

Animals↗
PubMed1998

Membranes of herpes simplex virus type-1-infected human corneal epithelial cells are not permeabilized to macromolecules and therefore do not release IL-1alpha.

Nanogram amounts of the proinflammatory cytokine interleukin-1alpha (IL-1alpha) were detected in uninfected cultures of human corneal epithelial cells (HCEC). Although HSV-1 replicated >10(4)-fold in these cells and caused extensive cytopathic effects, virus infection was not accompanied by significant extracellular release of IL-1alpha. Additional studies showed that release of radiolabeled cytosolic proteins from virus-infected HCEC was no greater than that released by mock-infected cells. These findings indicate that HSV-1 infection of HCEC does not result in IL-1alpha release because newly formed virus progeny can escape infected cells without disrupting cell membranes.

Cell Membrane↗
PubMed1998

Chemokine synthesis in the HSV-1-infected cornea and its suppression by interleukin-10.

Herpes simplex virus type 1 (HSV-1) infection of the murine cornea results in a tissue-destructive inflammatory response. In this study we show that virus infection induces the synthesis of macrophage inflammatory protein-2 (MIP-2), MIP-1alpha, and monocyte chemoattractant protein-1 (MCP-1). However, only the production of MIP-2 and MIP-1alpha coincided with the influx of leukocytes into the cornea. IL-10 treatment markedly suppressed chemokine message and protein synthesis in vivo. Local administration of IL-10 also dramatically reduced the number of T cells and neutrophils migrating into the cornea and suppressed the severity of corneal disease. The inflammatory response could also be suppressed by the passive transfer of neutralizing antibody to MIP-1alpha but not MCP-1. We conclude that local IL-10 administration can suppress chemokine synthesis, thereby ameliorating corneal disease. Furthermore, our results indicate that MIP-1alpha plays a major role in herpes stromal keratitis development, whereas MCP-1 does not.

Animals↗
PubMed1998

Absence of macrophage inflammatory protein-1alpha prevents the development of blinding herpes stromal keratitis.

Prior studies in our laboratory have suggested that the CC chemokine macrophage inflammatory protein-1alpha (MIP-1alpha) may be an important mediator in the blinding ocular inflammation which develops following herpes simplex virus type 1 (HSV-1) infection of the murine cornea. To directly test this hypothesis, MIP-1alpha-deficient (-/-) mice and their wild-type (+/+) counterparts were infected topically on the scarified cornea with 2.5 x 10(5) PFU of HSV-1 strain RE and subsequently graded for corneal opacity. Four weeks postinfection (p.i.), the mean corneal opacity score of -/- mice was 1.1 +/- 0.3 while that of the +/+ mice was 3.7 +/- 0.5. No detectable infiltrating CD4+ T cells were seen histologically at 14 or 21 days p.i. in -/- animals, whereas the mean CD4+ T-cell count per field (36 fields counted) in +/+ hosts was 26 +/- 2 (P < 0.001). In addition, neutrophil counts in the -/- mouse corneas were reduced by >80% in comparison to the wild-type controls. At 2 weeks p.i., no interleukin-2 or gamma interferon could be detected in six of seven -/- mice, whereas both T-cell cytokines were readily demonstrable in +/+ mouse corneas. Also, MIP-2 and monocyte chemoattractant protein-1 protein levels were significantly lower in MIP-1alpha -/- mouse corneas than in +/+ host corneas, suggesting that MIP-1alpha directly, or more likely indirectly, influences the expression of other chemokines. Interestingly, despite the paucity of infiltrating cells, HSV-1 clearance from the eyes of -/- mice was not significantly different from that observed in +/+ hosts. We conclude that MIP-1alpha is not needed to control virus growth in the cornea but is essential for the development of severe stromal keratitis.

Animals↗
PubMed1998

Role of MIP-2 in neutrophil migration and tissue injury in the herpes simplex virus-1-infected cornea.

PURPOSE: Neutrophils are the most prominent cell type to migrate initially into the herpes simplex virus type 1 (HSV-1)-infected murine cornea. The role the C-X-C chemokines macrophage inflammatory protein (MIP)-2 and KC play in promoting this response was investigated. METHODS: MIP-2 and KC were quantitated by enzyme-linked immunosorbent assay. Neutralization of endogenous MIP-2 and KC was achieved by subconjunctival inoculation of the appropriate antibody. Infected corneas were examined immunohistochemically for infiltrating leukocytes and assayed for myeloperoxidase activity using the dye o-dianisidine. Depletion of neutrophils and natural killer cells was accomplished by intraperitoneal administration of RB6-8C5 and asialo GM1 antibodies. RESULTS: Herpes simplex virus type 1, when introduced intracorneally, stimulated the production of MIP-2 and KC, with peak synthesis occurring 48 hours after infection. Dose-response studies showed that exogenous MIP-2 was three to four times more potent than KC in attracting neutrophils as assessed by myeloperoxidase assay and immunohistochemical staining. Subconjunctival administration of neutralizing antibody to MIP-2 resulted in a sharp decrease in neutrophil infiltration and significantly reduced corneal opacity scores. In contrast, in vivo treatment with neutralizing antibody to KC did not suppress ocular inflammation. Additional studies indicated that MIP-2 and KC could be made by corneal epithelial cells and that production was promoted by interleukin (IL)-1. In vivo depletion of neutrophils sharply reduced MIP-2 levels but did not affect KC levels. CONCLUSIONS: Collectively, the results suggest that MIP-2 is the major chemokine that attracts neutrophils into the HSV-1 infected cornea, where the cells directly or indirectly cause tissue injury. Resident corneal cells and inflammatory cells contribute to MIP-2 synthesis, whereas KC production seems to be confined largely to corneal cells.

Animals↗
PubMed1997

Differential induction of GRO alpha gene expression in human corneal epithelial cells and keratocytes exposed to proinflammatory cytokines.

PURPOSE: GRO alpha is an inducible neutrophil chemotactic factor synthesized in inflamed corneal tissues. In this study, the regulation of GRO alpha synthesis after exposure of human corneal cells to proinflammatory cytokines was investigated. METHODS: Pure cultures of human corneal epithelial cells and keratocytes were exposed to increasing concentrations of either interleukin-1 alpha (IL-1 alpha) or tumor-necrosis factor-alpha (TNF-alpha). At selected times postexposure, the amounts of GRO alpha produced by the cultures were quantitated by enzyme-linked immunosorbent assay. The RNA was harvested from stimulated cultures to monitor GRO alpha mRNA and pre-mRNA levels by the reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: Both IL-1 alpha and TNF-alpha induced significant levels of GRO alpha synthesis in keratocytes. However, IL-1 alpha-stimulated cells produced > 10 times more GRO alpha protein and 12 times more GRO alpha mRNA than did TNF-alpha-stimulated keratocytes. In contrast to the log differences in mRNA levels and protein synthesis, there was a less than twofold difference between IL-1 alpha and TNF-alpha in their capacity to induce GRO alpha specific pre-mRNA synthesis. When actinomycin D was added to stimulated keratocytes to inhibit transcription, the half-life of GRO alpha mRNA in TNF-alpha-treated cells was < 1 hour, whereas the half-life of the GRO alpha mRNA synthesized in IL-1 alpha-stimulated cells was > or = 9 hours. In contrast to keratocytes, exposure of corneal epithelial cells to IL-1 alpha and TNF-alpha did not induce significant increases in steady-state levels of GRO alpha pre-mRNA, mRNA, or protein. CONCLUSIONS: The results suggest that keratocytes are the major producers of GRO alpha in the human cornea. The capacity of IL-1 alpha to stimulate the synthesis of significantly higher quantities of GRO alpha in keratocytes compared to TNF-alpha is caused by the fact that GRO alpha-specific transcripts are more than nine times more stable in cells exposed to IL-1 alpha than in cells exposed to TNF-alpha.

Chemokine CXCL1↗
PubMed1996

Early cytokine synthesis in the excised mouse cornea.

Corneas excised from normal BALB/c mice and incubated in vitro were analyzed for the production of "early-warning" cytokines via reverse transcription-polymerase chain reaction and ELISA. It was found that the trauma of excision stimulated rapid IL-1 alpha synthesis, with peak protein accumulation occurring at 6 h, whereas IL-6 synthesis was maximal at 18 h. Neither IL-1 beta protein nor message was detected at any point, and TNF-alpha synthesis never increased above constituted levels. Antibody neutralization of endogenous IL-1 alpha blocked IL-6 synthesis. Addition of exogenous IL-1 alpha induced IL-1 alpha and IL-6 synthesis in vitro. Inoculation of IL-1 alpha into the cornea induced IL-6 synthesis in vivo. Addition of IL-1 alpha could stimulate IL-1R, IL-1 alpha, and IL-6 mRNA synthesis in the epithelial, stromal, and endothelial components of the cornea. However, protein production was readily detected only in the epithelial layer. We concluded that mechanical trauma to the mouse cornea triggers the enhanced synthesis of IL-1 alpha and IL-1R, which in turn results in the production of IL-6 and more IL-1 alpha. That corneal excision did not stimulate the synthesis of IL-1 beta or TNF-alpha indicates that there is a selective induction of early cytokine expression in this specialized tissue.

Animals↗
PubMed1996

Protective antibody therapy is associated with reduced chemokine transcripts in herpes simplex virus type 1 corneal infection.

Herpes simplex virus type 1 (HSV-1) infection on the murine cornea induces an intense inflammatory response which can lead to blindness. This disease, known as herpes stromal keratitis, can be prevented by the timely passive transfer of monoclonal antibody specific for viral glycoprotein D (gD). Precisely how antibody treatment prevents excessive corneal inflammation is not known. In this study we investigated whether chemokine mRNA expression is inhibited by antibody treatment. Total cellular RNAs isolated from normal corneas and at various times after virus infection were analyzed via reverse transcription-PCR for mRNA coding for seven different chemokines. Constitutive levels of IP-10, KC, MIP-2, MCP-1, MIP-1 beta, and RANTES mRNA were detected in uninfected corneas of BALB/c mice. When the cornea was mechanically traumatized, message for all six chemokines was transiently elevated above constitutive levels. In contrast, HSV-1 infection resulted in prolonged enhanced chemokine message expression. The kinetics of mRNA accumulation was distinctive for each chemokine analyzed. MIP-1 alpha message, not detected constitutively, was not evident until day 7 postinfection. Administration of anti-HSV gD monoclonal antibody 1 day after infection was associated with reduced message for MIP-2, MCP-1, MIP-1 alpha, and MIP-1 beta. IP-10, KC, and RANTES messages were not altered. Collectively, our results suggest that anti-gD treatment may protect, at least in part, by inhibiting production of chemokines believed to promote inflammation.

Animals↗
PubMed1996

Neutrophil-mediated suppression of virus replication after herpes simplex virus type 1 infection of the murine cornea.

Herpes simplex virus type 1 (HSV-1) infection of the murine cornea induces the rapid infiltration of neutrophils. We investigated whether these cells could influence virus replication. BALB/c mice treated with monoclonal antibody (MAb) RB6-8C5 experienced a profound depletion of neutrophils in the bloodstream, spleen, and cornea. In these animals, virus titers in the eye were significantly higher than those in the immunoglobulin G-treated controls at 3 days postinfection. By day 9, virus was no longer detectable in the controls, whereas titers of 10(3) to 10(6) PFU were still present in the neutrophil-depleted hosts. Furthermore, virus spread more readily to the skin and brains of MAb RB6-8C5-treated animals, rendering them significantly more susceptible to HSV-1-induced blepharitis and encephalitis. Only 25% of the treated animals survived, whereas all of the controls lived. Although MAb RB6-8C5 treatment did not alter the CD4+ T-cell, B-cell, natural killer cell, or macrophage populations, the CD8+ T-cell population was partially reduced. Therefore, the experiments were repeated in severe combined immunodeficiency mice, which lack CD8+ T cells. Again virus growth was found to be significantly elevated in the eyes, trigeminal ganglia, and brains of the MAb RB6-8C5-treated hosts. These results strongly indicate that in both immunocompetent and immunodeficient mice, neutrophils play a significant role in helping to control the replication and spread of HSV-1 after corneal infection.

Animals↗
PubMed1996

Proinflammatory cytokines induce RANTES and MCP-1 synthesis in human corneal keratocytes but not in corneal epithelial cells. Beta-chemokine synthesis in corneal cells.

PURPOSE: To determine whether human corneal epithelial cells and keratocytes produce chemokines regulated upon activation, normal T-cell expressed and secreted (RANTES) protein and monocyte chemotactic protein-1 (MCP-1) after exposure to proinflammatory cytokines interleukin-1 alpha (IL-1 alpha) and tumor necrosis factor-alpha (TNF-alpha). METHODS: Pure cultures of human corneal epithelial cells and keratocytes were exposed to increasing concentrations of either human recombinant IL-1 alpha or TNF-alpha. At selected time intervals after exposure, culture supernatants were removed and assayed for RANTES and MCP-1 by the enzyme-linked immunosorbent assay. Total RNA was extracted from the cell cultures, and steady state mRNA levels were measured by reverse transcriptase-polymerase chain reaction. RESULTS: Exposure to keratocytes to either IL-1 alpha or TNF-alpha resulted in > 100-fold increases in RANTES protein secretion and > 150-fold increases in MCP-1 protein secretion, as well as in rapid sustained increases in intracellular levels of their corresponding mRNAs. Exposure of corneal epithelial cells to IL-1 alpha and TNF-alpha did not stimulate MCP-1 secretion nor intracellular levels of MCP-1 mRNA. Epithelial cells also failed to secrete RANTES protein even through the two inducing cytokines did stimulate increased expression of RANTES mRNA. CONCLUSIONS: These results suggest that RANTES and MCP-1 gene expression in human keratocytes differs markedly from their expression in human corneal epithelial cells and that the stroma of the cornea may be more important than the epithelium in recruitment of mononuclear leukocytes responsible for cell-mediated immunity.

Adult↗