Novel potential biomarkers for the diagnosis and monitoring of patients with ulcerative colitis

Anti-integrin αvβ6 antibody in Takayasu arteritis patients with or without ulcerative colitis

Background

It has been well documented that Takayasu arteritis (TAK) and ulcerative colitis (UC) coexist in the same patients. HLA-B*52 characterizes the co-occurrence, which is one of the common genetic features between these two diseases, indicating shared underlying pathologic mechanisms. Anti-integrin αvβ6 antibody (Ab) is present in sera of UC patients in a highly specific manner. We investigated if there were any associations between anti-integrin αvβ6 Ab and TAK, considering the risk HLA alleles.

Methods

A total of 227 Japanese TAK patients were recruited in the current study and their serum samples were subjected to measurement of anti-integrin αvβ6 Ab by ELISA. The clinical information, including the co-occurrence of UC, was collected. The HLA allele carrier status was determined by Luminex or genotype imputation.

Results

The information about the presence of UC was available for 165 patients, among which eight (4.84%) patients had UC. Anti-integrin αvβ6 antibody was identified in 7 out of 8 TAK subjects with UC (87.5%) while only 5 out of 157 (3.18%) TAK subjects without UC had the antibody (OR 121, p=7.46×10-8). A total of 99 out of 218 (45.4%) patients were HLA-B*52 carriers. There was no significant association between the presence of anti-integrin αvβ6 Ab and HLA-B*52 carrier status in those without UC (OR 2.01, 95% CI 0.33-12.4, p = 0.189).

Conclusions

The prevalence of anti-integrin αvβ6 Ab was high in TAK patients with UC, but not in the absence of concomitant UC. The effect of HLA-B*52 on anti-integrin αvβ6 Ab production would be minimal.

Identified S100A9 as a target for diagnosis and treatment of ulcerative colitis by bioinformatics analysis

Ulcerative colitis (UC) is a chronic, recurrent inflammatory bowel disease. UC confronts with severe challenges including the unclear pathogenesis and lack of specific diagnostic markers, demanding for identifying predictive biomarkers for UC diagnosis and treatment. We perform immune infiltration and weighted gene co-expression network analysis on gene expression profiles of active UC, inactive UC, and normal controls to identify UC related immune cell and hub genes. Neutrophils, M1 macrophages, activated dendritic cells, and activated mast cells are significantly enriched in active UC. MMP-9, CHI3L1, CXCL9, CXCL10, CXCR2 and S100A9 are identified as hub genes in active UC. Specifically, S100A9 is significantly overexpressed in mice with colitis. The receiver operating characteristic curve demonstrates the excellent performance of S100A9 expression in diagnosing active UC. Inhibition of S100A9 expression reduces DSS-induced colonic inflammation. These identified biomarkers associated with activity in UC patients enlighten the new insights of UC diagnosis and treatment.

Biological, genetic and epigenetic markers in ulcerative colitis

In this review, we have summarized the existing knowledge of ulcerative colitis (UC) markers based on current literature, specifically, the roles of potential new biomarkers, such as circulating, fecal, genetic, and epigenetic alterations, in UC onset, disease activity, and in therapy response. UC is a complex multifactorial inflammatory disease. There are many invasive and non-invasive diagnostic methods in UC, including several laboratory markers which are employed in diagnosis and disease assessment; however, colonoscopy remains the most widely used method. Common laboratory abnormalities currently used in the clinical practice include inflammation-induced alterations, serum autoantibodies, and antibodies against bacterial antigens. Other new serum and fecal biomarkers are supportive in diagnosis and monitoring disease activity and therapy response; and potential salivary markers are currently being evaluated as well. Several UC-related genetic and epigenetic alterations are implied in its pathogenesis and therapeutic response. Moreover, the use of artificial intelligence in the integration of laboratory biomarkers and big data could potentially be useful in clinical translation and precision medicine in UC management.

Ulcerative colitis: shedding light on emerging agents and strategies in preclinical and early clinical development

INTRODUCTION

Ulcerative colitis (UC) is an inflammatory disease of the large intestine. Progress in preclinical therapeutic target discovery and clinical trial design has resulted in the approval of new therapies. Nonetheless, remission rates remain below 30% thus underlining the need for novel, more effective therapies.

AREAS COVERED

This paper reviews current experimental techniques available for drug testing in intestinal inflammation and examines new therapies in clinical development for the treatment of UC. The authors searched the literature for 'ulcerative colitis' AND 'preclinical' OR 'drug target/drug name' (i.e. infliximab, vedolizumab, IL-12, IL-23, JAK, etc.). Studies that included preclinical in vivo or in vitro experiments are discussed. The clinicaltrial.gov site was searched for 'ulcerative colitis' AND 'Recruiting' OR 'Active, not recruiting' AND 'Interventional (Clinical Trial)' AND 'early phase 1' OR 'phase 1' OR 'phase 2' OR 'phase 3.'

EXPERT OPINION

Using in vivo, ex vivo, and/or in vitro models could increase the success rates of drugs moving to clinical trials, and hence increase the efficiency of this costly process. Selective JAK1 inhibitors, S1P modulators, and anti-p19 antibodies are the most promising options to improve treatment effectiveness. The development of drugs with gut-restricted exposure may provide increased efficacy and an improved safety.

Identification of an Anti-Integrin αvβ6 Autoantibody in Patients With Ulcerative Colitis

BACKGROUND AND AIMS

Ulcerative colitis is the most frequent type of inflammatory bowel disease and is characterized by colonic epithelial cell damage. Although involvement of autoimmunity has been suggested in ulcerative colitis, specific autoantigens/antibodies have yet to be elucidated.

METHODS

Using 23 recombinant integrin proteins, we performed enzyme-linked immunosorbent assays on sera from patients with ulcerative colitis and controls. Integrin expression and IgG binding in the colon tissues of patients with ulcerative colitis and controls were examined using immunofluorescence and coimmunoprecipitation, respectively. The blocking activity of autoantibodies was examined using solid-phase binding and cell adhesion assays.

RESULTS

Screening revealed that patients with ulcerative colitis had IgG antibodies against integrin αvβ6. In the training and validation groups, 103 of 112 (92.0%) patients with ulcerative colitis and only 8 of 155 (5.2%) controls had anti-integrin αvβ6 antibodies (P < .001), resulting in a sensitivity of 92.0% and a specificity of 94.8% for diagnosing ulcerative colitis. Anti-integrin αvβ6 antibody titers coincided with ulcerative colitis disease activity, and IgG1 was the major subclass. Patient IgG bound to the integrin αvβ6 expressed on colonic epithelial cells. Moreover, IgG of patients with ulcerative colitis blocked integrin αvβ6-fibronectin binding through an RGD (Arg-Gly-Asp) tripeptide motif and inhibited cell adhesion.

CONCLUSIONS

A significant majority of patients with ulcerative colitis had autoantibodies against integrin αvβ6, which may serve as a potential diagnostic biomarker with high sensitivity and specificity.

Elevated systemic immune inflammation index level is associated with disease activity in ulcerative colitis patients

BACKGROUND

It has been confirmed that high Systemic immune-inflammation index (SII) levels usually indicate poor outcomes in various diseases, especially on malignancies. However, the clinical significance of the SII in ulcerative colitis (UC) patients is remain unclear. Therefore, the purpose of our paper is to analyze the levels of SII in UC patients and assess the relationship between the SII and disease activity.

MATERIALS AND METHODS

We studied 187 consecutive patients with UC and 185 age- and sex-matched healthy controls retrospectively. The Mayo scoring system was adopted to evaluate disease activity in UC patients. We collected clinical characteristics and laboratory parameters from hospital electronic medical records.

RESULTS

The SII levels were significantly higher in UC patients than those in healthy subjects (P < 0.001). Higher SII levels were observed in moderate and severe UC subgroups compared to mild or remission subgroups. Correlation analysis displayed that the SII levels were positively relatived with Mayo score (r = 0.469, P < 0.001), C reactive protein (CRP) (r = 0.480, P < 0.001), and erythrocyte sedimentation rate (ESR) (r = 0.336, P < 0.001), but negatively with haemoglobin (Hb) (r = -0.271, P < 0.001). A multiple linear regression analysis suggested that there was an independent correlation between Mayo score and SII (beta = 0.324, t = 4.241, P < 0.001). The receiver operating characteristic (ROC) curve revealed that the maximum area under the curve (AUC) was 0.711 (95% CI, 0.630-0.791, P < 0.001), and the cut-off value for diagnosing active UC was 485.95, the sensitivity was 0.641, and the specificity was 0.75.

CONCLUSIONS

We demonstrated that the SII was elevated significantly in UC patients and was closely related to the UC disease activity. In addition, the SII had a high discriminative capacity for active UC.