Location-based prediction model for Crohn’s disease regarding a novel serological marker,anti-chitinase 3-like 1 autoantibodies

BACKGROUND Defective neutrophil regulation in inflammatory bowel disease(IBD)is thought to play an important role in the onset or manifestation of IBD,as it could lead to damage of the intestinal mucosal barrier by the infiltration of neutrophils in the inflamed mucosa and the accumulation of pathogens.Like neutrophils in the context of innate immune responses,immunoglobulin A(IgA)as an acquired immune response partakes in the defense of the intestinal epithelium.Under normal conditions,IgA contributes to the elimination of microbes,but in connection with the loss of tolerance to chitinase 3-like 1(CHI3L1)in IBD,IgA could participate in CHI3L1-mediated improved adhesion and invasion of potentially pathogenic microorganisms.The tolerance brake to CHI3L1 and the occurrence of IgA autoantibodies to this particular target,the exact role and underlying mechanisms of CHI3L1 in the pathogenesis of IBD are still unclear.AIM To determine the predictive potential of Ig subtypes of a novel serological marker,anti-CHI3L1 autoantibodies(aCHI3L1)in determining the disease phenotype,therapeutic strategy and long-term disease course in a prospective referral cohort of adult IBD patients.METHODS Sera of 257 Crohn’s disease(CD)and 180 ulcerative colitis(UC)patients from a tertiary IBD referral center of Hungary(Division of Gastroenterology,Department of Internal Medicine,Faculty of Medicine,University of Debrecen)were assayed for IgG,IgA,and secretory IgA(sIgA)type aCHI3L1 by enzyme-linked immunosorbent assay using recombinant CHI3L1,along with 86 healthy controls(HCONT).RESULTS The IgA type was more prevalent in CD than in UC(29.2%vs 11.1%)or HCONT(2.83%;P<0.0001 for both).However,sIgA subtype aCHI3L1 positivity was higher in both CD and UC patients than in HCONT(39.3%and 32.8%vs 4.65%,respectively;P<0.0001).The presence of both IgA and sIgA aCHI3L1 antibodies was associated with colonic involvement(P<0.0001 and P=0.038,respectively)in patients with CD.Complicated disease behavior at sample procurement was associated with aCHI3L1 sIgA positivity(57.1%vs 36.0%,P=0.009).IgA type aCH3L1 was more prevalent in patients with frequent relapse during the disease course in the CD group(46.9%vs 25.7%,P=0.005).In a group of patients with concomitant presence of pure inflammatory luminal disease and colon involvement at the time of diagnosis,positivity for IgA or sIgA type aCH3L1 predicted faster progression towards a complicated disease course in time-dependent models.This association disappeared after merging subgroups of different disease locations.CONCLUSION CHI3L1 is a novel neutrophil autoantigenic target in IBD.The consideration of antibody classes along with location-based prediction may transform the future of serology in IBD.

Potential role of chitinase 3-like-1 in inflammation-associated carcinogenic changes of epithelial cells

The family of mammalian chitinases includes members both with and without glycohydrolase enzymatic activity against chitin, a polymer of N-acetylglucosamine. Chitin is the structural component of fungi, crustaceans, insects and parasitic nematodes, but is completely absent in mammals. Exposure to antigens containing chitin- or chitin-like structures sometimes induces strong T helper type-I responses in mammals, which may be associated with the induction of mammalian chitinases. Chitinase 3-like-1 （CHI3L1）, a member of the mammalian chitinase family, is induced specifically during the course of inflammation in such disorders as inflammatory bowel disease, hepatitis and asthma. In addition, CHI3L1 is expressed and secreted by several types of solid tumors including glioblastoma, colon cancer, breast cancer and malignant melanoma. Although the exact function of CHI3L1 in inflammation and cancer is still largely unknown, CHI3L1 plays a pivotal role in exacerbating the inflammatory processes and in promoting angiogenesis and remodeling of the extracellular matrix. CHI3L1 may be highly involved in the chronic engagement of inflammation which potentiates development of epithelial tumorigenesis presumably by activating the mitogen-activated protein kinase and the protein kinase B signaling pathways. Anti-CHI3L1 antibodies or pan-chitinase inhibitors may have the potential to suppress CHI3Ll-mediated chronic inflammation and the subsequent carcinogenic change in epithelial cells.

Increased expression and possible role of chitinase 3-like-1 in a colitis-associated carcinoma model

AIM: To investigate the possible role of chitinase 3-like-1 (CHI3L1) in the progression of colitis-associated carcinoma (CAC).

Chitinase 3-like 1 secreted by peritumoral macrophages in esophageal squamous cell carcinoma is a favorable prognostic factor for survival

AIM To identify whether chitinase 3-like 1(CHI3 L1) serves as a suitable biomarker for the prognosis of esophageal squamous cell carcinoma(ESCC) and to analyze this protein's cellular source.METHODS An ELISA was conducted to detect the concentration of CHI3 L1 in the serum of 150 ESCC patients diagnosed between January 2001 and February 2005. The prognostic relevance of CHI3 L1 was evaluated by a Kaplan-Meier and Cox regression analysis. The immunohistochemistry was reanalyzed,and fluorescent staining was utilized to explore the cellular origins of CHI3 L1. We stimulated monocyte-derived macrophages(MDMs) with either IL-6 or the supernatant of the ESCC cell line Eca-109 and later investigated the level of CHI3 L1 by q PCR and ELISA.RESULTS The level of serum CHI3 L1 was higher in older patients(≥ 60) than in patients under the age of 60(P = 0.001). The patients with higher levels of CHI3 L1 had a significantly shorter overall survival,whereas the traditional markers,carcinoembryonic antigen and squamous cell carcinoma antigen,were less effective(P > 0.05). A multivariate Cox analysis(P = 0.001) indicated that CHI3 L1 was an independent prognostic factor for ESCC patients. Peritumoral macrophages in ESCC exhibited high levels of CHI3 L1. Interleukin-6(IL-6) and the supernatant of Eca-109 containing IL-6 stimulated MDMs to secrete CHI3 L1. The serum concentration of CHI3 L1 in the ESCC patients showed a weak correlation with the laboratory inflammatory parameters neutrophil(NEU,P = 0.045),neutrophil/lymphocyte rate(NLR,P = 0.016),and C-reactive protein(CRP,P < 0.001).CONCLUSION Our study first established a connection between the pretreated CHI3 L1 and patients with ESCC,and the serum CHI3 L1 was primarily secreted by ESCC-surrounded macrophages.

Evaluation of trabecular meshwork-specific promoters in vitro and in vivo using scAAV2 vectors expressing C3 transferase

AIM:To evaluate the potential of two trabecular meshwork(TM)-specific promoters,Chitinase 3-like 1(Ch3L1)and matrix gla protein(MGP),for improving specificity and safety in glaucoma gene therapy based on self-complementary AAV2(scAAV2)vector technologies.METHODS:An scAAV2 vector with C3 transferase(C3)as the reporter gene(scAAV2-C3)was selected.The scAAV2-C3 vectors were driven by Ch3L1(scAAV2-Ch3L1-C3),MGP(scAAV2-MGP-C3),enhanced MGP(scAAV2-eMGP-C3)and cytomegalovirus(scAAV2-CMV-C3),respectively.The cultured primary human TM cells were treated with each vector at different multiplicities of infections.Changes in cell morphology were observed by phase contrast microscopy.Actin stress fibers and Rho GTPases/Rho-associated protein kinase pathway-related molecules were assessed by immunofluorescence staining,real-time quantitative polymerase chain reaction and Western blot.Each vector was injected intracamerally into the one eye of each rat at low and high doses respectively.In vivo green fluorescence was visualized by a Micron III Retinal Imaging Microscope.Intraocular pressure(IOP)was monitored using a rebound tonometer.Ocular responses were evaluated by slit-lamp microscopy.Ocular histopathology analysis was examined by hematoxylin and eosin staining.RESULTS:In TM cell culture studies,the vectormediated C3 expression induced morphologic changes,disruption of actin cytoskeleton and reduction of fibronectin expression in TM cells by inhibiting the Rho GTPases/Rhoassociated protein kinase signaling pathway.At the same dose,these changes were significant in TM cells treated with scAAV2-CMV-C3 or scAAV2-Ch3L1-C3,but not in cells treated with scAAV2-eMGP-C3 or scAAV2-MGP-C3.At lowinjected dose,the IOP was significantly decreased in the scAAV2-Ch3L1-C3-injected eyes but not in scAAV2-MGPC3-injected and scAAV2-eMGP-C3-injected eyes.At highinjected dose,significant IOP reduction was observed in the scAAV2-eMGP-C3-injected eyes but not in scAAV2-MGP-C3-injected eyes.Similar to scAAV2-CMV-C3,scAAV2-Ch3L1-C3 vector showed efficient transduction both in the TM and corneal endothelium.In anterior segment tissues of scAAV2-eMGP-C3-injected eyes,no obvious morphological changes were found except for the TM.Inflammation was absent.CONCLUSION:In scAAV2-transduced TM cells,the promoter-driven efficiency of Ch3L1 is close to that of cytomegalovirus,but obviously higher than that of MGP.In the anterior chamber of rat eye,the transgene expression pattern of scAAV2 vector is presumably affected by MGP promoter,but not by Ch3L1 promoter.These findings would provide a useful reference for improvement of specificity and safety in glaucoma gene therapy using scAAV2 vector.

Novel methylxanthine derivative-mediated anti-inflammatory effects in inflammatory bowel disease

Family 18 chitinases have a binding capacity with chitin, a polymer of N-acetylglucosamine. Recent studies strongly suggested that chitinase 3-like 1(CHI3L1, also known as YKL-40) and acidic mammalian chitinase, the two major members of family 18 chitinases, play a pivotal role in the pathogenesis of inflammatory bowel disease(IBD), bronchial asthma and several other inflammatory disorders. Based on the data from highthroughput screening, it has been found that three methylxanthine derivatives, caffeine, theophylline, and pentoxifylline, have competitive inhibitory effects against a fungal family 18 chitinase by specifically interacting with conserved tryptophans in the active site of this protein. Methylxanthine derivatives are also known as adenosine receptor antagonists, phosphodiesterase inhibitors and histone deacetylase inducers. Anti-in-flammatory effects of methylxanthine derivatives have been well-documented in the literature. For example, a beneficial link between coffee or caffeine consumption and type 2 diabetes as well as liver cirrhosis has been reported. Furthermore, theophylline has a long history of being used as a bronchodilator in asthma therapy, and pentoxifylline has an immuno-modulating effect for peripheral vascular disease. However, it is still largely unknown whether these methylxanthine derivativemediated anti-inflammatory effects are associated with the inhibition of CHI3L1-induced cytoplasmic signaling cascades in epithelial cells. In this review article we will examine the above possibility and summarize the biological significance of methylxanthine derivatives in intestinal epithelial cells. We hope that this study will provide a rationale for the development of methylxanthine derivatives, in particular caffeine,-based antiinflammatory therapeutics in the field of IBD and IBDassociated carcinogenesis.