Glycyrrhizin Interacts with TLR4 and TLR9 to Resolve Keratitis.

This study tests the mechanism(s) of glycyrrhizin (GLY) protection against keratitis. Female C57BL/6 (B6), TLR4 knockout (TLR4KO), myeloid specific TLR4KO (mTLR4KO), their wildtype (WT) littermates, and TLR9 knockout (TLR9KO) mice were infected with KEI 1025 and treated with GLY or PBS onto the cornea after infection. Clinical scores, photography with a slit lamp, RT-PCR and ELISA were used.

Type II Collagen-Specific B Cells Induce Immune Tolerance in Th1-Skewed, Th2-Skewed, and Arthritis-Prone Strains of Mice.

Antigen-specific regulatory T cells play key immune suppressive roles in autoimmune disease models and regulate the peripheral tolerance achieved via anterior chamber-associated immune deviation (ACAID). Articular cartilage has type II collagen (CII), which is a potent autoantigen protein in arthritis. There has not been much research on the clinical importance of CII-associated diseases.

Disruption of GPR35 Exacerbates Dextran Sulfate Sodium-Induced Colitis in Mice.

Background: G protein-coupled receptor 35 (GPR35) is an orphan receptor and is vastly expressed in immune cells and gastrointestinal cells, suggesting the potential physiological importance of GPR35 in these cells. Here, we tested the hypothesis that the lack of GPR35 expression in the colon mucosa exacerbates the severity of dextran sulfate sodium (DSS)-induced experimental colitis in mice.

Methods: Colitis was induced in GPR35 wild-type (GPR35) and GPR35 knockout (GPR35) mice through the administration of DSS in drinking water for 5 days followed by regular facility water for 1 day.

A critical role of CXCR2 PDZ-mediated interactions in endothelial progenitor cell homing and angiogenesis.

Bone marrow-derived endothelial progenitor cells (EPCs) contribute to neovessel formation in response to growth factors, cytokines, and chemokines. Chemokine receptor CXCR2 and its cognate ligands are reported to mediate EPC recruitment and angiogenesis. CXCR2 possesses a consensus PSD-95/DlgA/ZO-1 (PDZ) motif which has been reported to modulate cellular signaling and functions.

Eye-mediated immune tolerance to Type II collagen in arthritis-prone strains of mice.

Type II collagen (CII) is a cartilage structural protein that plays important roles in joint function, arthritis and ageing. In studying the ability of CII to induce eye-mediated specific immune tolerance, we have recently proven that CII is capable of inducing anterior chamber-associated immune deviation (ACAID) in Balb/c mice. Here, we study the ability of CII to induce eye-mediated immune tolerance in strains of mice that are prone to the induction of rheumatoid arthritis.

The in vivo and in vitro induction of anterior chamber associated immune deviation to myelin antigens in C57BL/6 mice.

Introduction of antigens into the anterior chamber (AC) of the eye generates a specific systemic form of tolerance that is termed AC-associated immune deviation (ACAID). Experimental autoimmune encephalomyelitis (EAE) is an animal model of the human CNS demyelinating diseases, including multiple sclerosis (MS) and acute disseminated encephalomyelitis. We investigated whether the encephalitogenic antigens myelin oligodendrocyte glycoprotein (MOG35-55) or myelin basic protein (MBP) induce ACAID in the EAE-prone C57BL/6 mice.

C-phycocyanin confers protection against oxalate-mediated oxidative stress and mitochondrial dysfunctions in MDCK cells.

Oxalate toxicity is mediated through generation of reactive oxygen species (ROS) via a process that is partly dependent on mitochondrial dysfunction. Here, we investigated whether C-phycocyanin (CP) could protect against oxidative stress-mediated intracellular damage triggered by oxalate in MDCK cells. DCFDA, a fluorescence-based probe and hexanoyl-lysine adduct (HEL), an oxidative stress marker were used to investigate the effect of CP on oxalate-induced ROS production and membrane lipid peroxidation (LPO).

Blockade of CXCR2 signalling: a potential therapeutic target for preventing neutrophil-mediated inflammatory diseases.

Polymorphonuclear neutrophils (PMN) play a key role in host innate immune responses by migrating to the sites of inflammation. Furthermore, PMN recruitment also plays a significant role in the pathophysiology of a plethora of inflammatory disorders such as chronic obstructive pulmonary disease (COPD), gram negative sepsis, inflammatory bowel disease (IBD), lung injury, and arthritis. Of note, chemokine-dependent signalling is implicated in the amplification of immune responses by virtue of its role in PMN chemotaxis in most of the inflammatory diseases.

In vitro-induced cell-mediated immune deviation to encephalitogenic antigens.

The injection of antigens into the Anterior Chamber (AC) of the eye induces Anterior Chamber Associated Immune Deviation (ACAID), which is a potent form of immune deviation that is largely attributed to the effect of TGFβ2 in the aqueous humor on ocular antigen-presenting cells (APCs). ACAID antigen presentation via APCs and B cells leads to the generation of antigen-specific T regulatory cells. The encephalitogenic antigens Myelin oligodendrocyte glycoprotein (MOG) and Myelin basic protein (MBP) have an obvious clinical relevance.

Eye-mediated induction of specific immune tolerance to encephalitogenic antigens.

Aims: Administration of antigens into the anterior chamber (AC) of the eye induces a form of antigen-specific immune tolerance termed anterior chamber-associated immune deviation (ACAID). This immune tolerance effectively impairs host delayed-type hypersensitivity (DTH) responses. We hypothesized that ACAID could be generated in BALB/c mice following AC inoculation of the encephalitogenic antigens myelin oligodendrocyte glycoprotein (MOG) and myelin basic protein (MBP).

Type II collagen induces peripheral tolerance in BALB/c mice via the generation of CD8+ T regulatory cells.

Antigens introduced into the anterior chamber (AC) of the eye induce a potent form of antigen-specific peripheral immune tolerance termed AC-associated immune deviation (ACAID), which prevents inflammatory immune responses and is characterized by impaired delayed-type hypersensitivity (DTH) responses. Type-II collagen (CII) is a fibrillar protein expressed exclusively in cartilage tissues. Although of its clinical relevance to Rheumatoid arthritis, aging, and osteoarthritis, there have been no studies to date to test if CII has the ability to induce ACAID.

Neutrophil infiltration of the colon is independent of the FPR1 yet FPR1 deficient mice show differential susceptibilities to acute versus chronic induced colitis.

Background: The receptor for formylated peptides, formyl peptide receptor 1 (FPR1), potently activates and serves as a chemoattractant receptor for neutrophils.

Aim: Given the abundance of neutrophils in the inflamed colon, our aim was to determine if the FPR1 mediates colonic neutrophil migration, using the dextran sodium sulfate (DDS)-induced model of colitis.

Methods: Formyl peptide receptor 1 gene-deficient mice were administered DDS in drinking water for a single 5-day period (acute) or in two 5-day periods separated by 16 days (chronic).

A chemokine receptor CXCR2 macromolecular complex regulates neutrophil functions in inflammatory diseases.

Inflammation plays an important role in a wide range of human diseases such as ischemia-reperfusion injury, arteriosclerosis, cystic fibrosis, inflammatory bowel disease, etc. Neutrophilic accumulation in the inflamed tissues is an essential component of normal host defense against infection, but uncontrolled neutrophilic infiltration can cause progressive damage to the tissue epithelium. The CXC chemokine receptor CXCR2 and its specific ligands have been reported to play critical roles in the pathophysiology of various inflammatory diseases.

The functional significance behind expressing two IL-8 receptor types on PMN.

PMN are critical to innate immunity and are fundamental to antibacterial defense. To localize to sites of infection, PMN possess receptors that detect chemoattractant stimuli elicited at the site, such as chemokines, complement split products, or bioactive lipids. Signaling through these receptors stimulates chemotaxis toward the site of infection but also activates a number of biochemical processes, with the result that PMN kill invading bacteria.

Therapeutic effect of blocking CXCR2 on neutrophil recruitment and dextran sodium sulfate-induced colitis.

Dextran sodium sulfate (DSS)-induced colitis in mice is characterized by polymorphonuclear neutrophil (PMN) infiltration into the colonic mucosa and lumen. The mechanism by which this occurs is unclear. To begin to understand the mechanism, we determined the role of the PMN chemokine receptor, CXCR2, in DSS-induced colitis by using CXCR2(-/-) mice or by neutralizing CXCR2.

Epidemiological studies on pulmonary pathogens in HIV-positive and -negative subjects with or without community-acquired pneumonia with special emphasis on Mycoplasma pneumoniae.

The prevalence of Mycoplasma pneumoniae among HIV-positive patients with community-acquired pneumonia (CAP) remains unclear. We investigated 300 HIV-positive adults (200 with CAP and 100 with no respiratory illness) and 75 HIV-negative adults with CAP for the prevalence of respiratory pathogens using culture and serology. A growth inhibition test was employed to confirm the isolates of M.

Investigation on the early events of apoptosis in senescent erythrocytes with special emphasis on intracellular free calcium and loss of phospholipid asymmetry in chronic renal failure.

Background: The pathophysiological link between increased blood concentrations of factors responsible for the derangement and erythrocyte membrane functions in chronic renal failure (CRF) patients are not thoroughly elucidated. We studied the erythrocyte characteristics and phospholipid asymmetry loss in CRF patients with different grades of uremia and also examined the involvement of intracellular free Ca(2+) in early events of apoptosis in uremic erythrocytes.

Methods: The studied population consisted of 90, age and sex matched control subjects (Group I) and 238 CRF cases divided into 3 groups (Group II, III and IV) according to urea concentrations and complexity of secondary complications.

Oxalate mediated nephronal impairment and its inhibition by c-phycocyanin: a study on urolithic rats.

The assumption of oxidative stress as a mechanism in oxalate induced renal damage suggests that antioxidants might play a beneficial role against oxalate toxicity. An in vivo model was used to investigate the effect of C-phycocyanin (from aquatic micro algae; Spirulina spp.), a known antioxidant, against calcium oxalate urolithiasis.

Credentials of Spirulina diet on stability and flux related properties on the biomineralization process during oxalate mediated renal calcification in rats.

Background: High Spirulina diet is a potential risk factor for nephrolithiasis since it has the capacity to increase urinary oxalate and uric acid level, facilitating lithogenesis. Our aim was to identify the effect of Spirulina diet during hyperoxaluric condition in Wistar albino rats.

Methods: The animals were divided into four groups: control (Gl, n=6); ethylene glycol (EG) induced (G2, n=6); EG+Spirulina (G3, n=6); Spirulina alone (G4, n=6).

Salubrious effect of C-phycocyanin against oxalate-mediated renal cell injury.

Background: C-phycocyanin, a biliprotein pigment found in some blue green algae (Spirulina platensis) with nutritional and medicinal properties, was investigated for its efficacy on sodium oxalate-induced nephrotoxicity in experimentally induced urolithic rats.

Methods: Male Wistar rats were divided into four groups. Hyperoxaluria was induced in two of these groups by intraperitoneal infusion of sodium oxalate (70 mg/kg), and a pretreatment of phycocyanin (100 mg/kg) as a single oral dosage was given to one of these groups by 1 h prior to sodium oxalate infusion challenges.

Prophylactic role of phycocyanin: a study of oxalate mediated renal cell injury.

Oxalate induced renal calculi formation and the associated renal injury is thought to be caused by free radical mediated mechanisms. An in vivo model was used to investigate the effect of phycocyanin (from Spirulina platensis), a known antioxidant, against calcium oxalate urolithiasis. Male Wistar rats were divided into four groups.