Association of Serum Immunoglobulins Levels With Specific Disease Phenotypes of Crohn's Disease: A Multicenter Analysis in China

Drug Repurposing to Inhibit Oncostatin M in Crohn's Disease

Crohn's disease is an inflammatory bowel disease (IBD) that currently lacks satisfactory treatment options. Therefore, new targets for new drugs are urgently needed to combat this disease. In the present study, we investigated the transcriptomics-based mRNA expression of intestinal biopsies from patients with Crohn's disease. We compared the mRNA expression profiles of the ileum and colon of patients with those of healthy individuals. A total of 72 genes in the ileum and 33 genes in the colon were differentially regulated. Among these, six genes were overexpressed in both tissues, including IL1B, TCL1A, HCAR3, IGHG1, S100AB, and OSM. We further focused on OSM/oncostatin M. To confirm the responsiveness of intestinal tissues from patients with Crohn's disease to oncostatin M inhibition, we examined the expression of the oncostatin M using immunohistochemistry in patient biopsies as well as in kindlin-1-/- and kindlin-2-/- knockout mice, which exhibit an inflammatory bowel disease (IBD) phenotype, and found strong oncostatin M expression in all samples examined. Next, we conducted a drug-repurposing study using the supercomputer MOGON and bioinformatic methods. A total of 13 candidate compounds out of 1577 FDA-approved drugs were identified by PyRx-based virtual drug screening and AutoDock-based molecular docking. Their lowest binding energies (LBEs) ranged from -10.46 (±0.08) to -8.77 (±0.08) kcal/mol, and their predicted inhibition constants (pKi) ranged from 21.62 (±2.97) to 373.78 (±36.78) nM. Ecamsule has an interesting stereostructure with two C2-symmetric enantiomers (1S,4R-1'S,4'R and 1R,4S-1'R,4'S) (1a and 1b) and one meso diastereomer (1S,4R-1'R,4'S) (1c). These three stereoisomers showed strong, albeit differing, binding affinities in molecular docking. As examined by nuclear magnetic resonance and polarimetry, the 1S,4R-1'S,4'R isomer was the stereoisomer present in our commercially available preparations used for microscale thermophoresis. Ecamsule (1a) was chosen for in vitro validation using recombinant oncostatin M and microscale thermophoresis. Considerable dissociation constants were obtained for ecamsule after three repetitions with a Kd value of 11.36 ± 2.83 µM. Subsequently, we evaluated, by qRT-PCR, the efficacy of ecamsule (1a) as a potential drug that could prevent oncostatin M activation by inhibiting downstream inflammatory marker genes (IL6, TNFA, and CXCL11). In conclusion, we have identified oncostatin M as a promising new drug target for Crohn's disease through transcriptomics and ecamsule as a potential new drug candidate for Crohn's disease through a drug-repurposing approach both in silico and in vitro.

Immunomodulatory Effects of L-Arginine-Modified Silkworm Pupae Protein Enteral Nutrition on Murine Intestinal Morphology and Immunity

L-arginine, a semi-essential amino acid, is well-documented for its role in nitric oxide (NO) synthesis, its anti-inflammatory properties, and its modulation of immune responses. Studies suggest it may improve gut barrier function and reduce inflammation in conditions such as colitis or sepsis. However, its specific efficacy in diabetic enteropathy (a complication of diabetes involving intestinal dysfunction, inflammation, and neuropathy) is less studied. To verify whether L-arginine and silkworm pupae components have a role in the treatment of diabetic enteropathy via the regulation of other cytokines and suppression of CD4+ T lymphocyte proliferation, a special medical-purpose formula containing both of these components was tested. For the first time, we have integrated L-arginine and silkworm pupae protein into enteral nutrition formulations for testing its anti-inflammatory potential. We have found that these formulations can improve the characteristics of diabetic intestinal inflammation through nutrient-modulating effects and nutritional efficacy. In addition, L-arginine (L-arginine, L-arg) enhances the immunomodulatory effects of special medical purpose formulas for diabetes mellitus. We utilized an oxidative stress model of small intestinal epithelial cells induced by high glucose and an inflammation model of the small intestine triggered by lipopolysaccharide in mice. The aim was to further investigate the protective effects of L-arginine and enteral nutritional preparations derived from silkworm pupae protein components on the intestinal tract. This research seeks to establish a theoretical foundation for understanding how L-arginine and these nutritional preparations regulate intestinal inflammation in vivo.

Crohn's disease-associated IgA nephropathy may prone to better renal outcome

BACKGROUND AND AIM

Renal involvement in Crohn's Disease (CD) was rare in the population. Little was known between IgA nephropathy and CD. This study aimed to investigate the differences in clinical and outcome features of CD-associated IgA nephropathy (CD-IgAN) and primary IgA nephropathy (PIgAN).

METHODS

Clinical data of patients diagnosed with IgAN by kidney biopsy were collected in the Sixth Affiliated Hospital of Sun Yat-sen University from January 1st, 2016 to June 1st, 2023. 17 patients with CD-IgAN and 87 patients with PIgAN were enrolled in this retrospective study.

RESULTS

Compared with PIgAN patients, CD-IgAN patients had lower levels of urinary protein excretion (1.57 g per 24 h vs. 0.33 g per 24 h, p < 0.01), but higher levels of estimated glomerular filtration rate (77.63 ± 40.11 ml per min per 1.73m2 vs. 104.53 ± 32.97 ml per min per 1.73m2, p = 0.008). From the point of renal pathology of PIgAN, patients with CD-IgAN had a less incidence of tubular atrophy or interstitial fibrosis (p = 0.001). CD-IgAN patients had a higher incidence of complete remission of proteinuria (45.8% vs. 81.8%, p = 0.031) or hematuria (10.4% vs. 45.4%, p = 0.019) than PIgAN patients after twelve-month treatments.

CONCLUSIONS

CD-IgAN manifests a milder progression of renal function than those PIgAN. After the treatment, proteinuria or hematuria are more prone to remit in patients with CD-IgAN.

Changes in Immunoglobulins G and A in the Saliva and Serum of Horses with Equine Gastric Ulcer Syndrome (EGUS) and Their Relationship with Other Immune and Redox Status Biomarkers

Equine Gastric Ulcer Syndrome (EGUS) is a widespread disease with a very high prevalence and importance in horses. It includes two conditions: Equine squamous gastric disease (ESGD), linked to acid disturbances, and Equine Glandular Gastric Disease (EGGD), associated with inflammation and immune system issues. In saliva, increased levels of immunological markers have been observed in this disease, indicating immune system involvement. In addition, changes in biomarkers of oxidative stress have been described. In horses, IgG and IgA are proteins that appear in saliva and serum and are considered to be the major proteins in specific immunity; however, their levels in horses with EGUS have not been previously studied. This report aims to evaluate IgG and IgA concentrations in the saliva and serum of horses with EGUS, measured by automated assays, and compare them with other biomarkers of the immune and oxidative stress system. This work validated the IgG and IgA assays in saliva and showed that IgA significantly increased in the saliva of horses with EGUS. When the correlation between IgG and IgA and other biomarkers of immune system issues and oxidative stress such as ADA, S100 A8-A9 (calprotectin), S100 A12 (calgranulin), uric acid, FRAS, and AOPP was studied, IgA in saliva showed a significant moderate correlation with adenosine deaminase, indicating its possible involvement in the immune reaction occurring in EGUS.

Serum immunoglobulin A (IgA) levels in children affected with Juvenile Idiopathic Arthritis

BACKGROUND AND OBJECTIVE

Immunoglobulin A (IgA) is the most abundant antibody isotype in the human body, considering its presence on the mucosal surfaces, in addition to the amount circulating in the bloodstream. Serum IgA levels can be variably altered in several pathological settings. However, very few studies specifically investigated serum IgA in Juvenile Idiopathic Arthritis (JIA). In the present study, we specifically assessed serum IgA levels in our cohort of patients affected with JIA.

METHODS

In this cross-sectional study, serum IgA levels were measured in patients with JIA (and age-matched controls) and analyzed according to age class. The correlation of serum IgA levels with hematological, inflammatory, and disease activity parameters was assessed.

RESULTS

No significant difference in the frequency of low IgA levels (according to the definition of complete and partial IgA deficiency) was observed between JIA patients and controls, overall. This pediatric study population showed a progressive increase of total serum IgA concentrations with age, as expected; however, in JIA patients aged 10-17 years, total IgA serum levels resulted to be significantly higher than in age-matched control subjects. No clear correlation between IgA levels and the examined inflammatory, hematological, and disease activity parameters was observed in JIA patients, except for the erythrocyte sedimentation rate (ESR) in oligoarticular JIA patients: here, serum IgA levels showed a positive and moderate covariation with ESR, which was also observed for disease activity (JADAS-10) in selected oJIA patients without biological therapy.

CONCLUSIONS

In our cohort of JIA patients, total serum IgA levels were not reduced and were actually increased in adolescents compared to controls. Larger studies are needed to confirm this finding, which cannot be certainly explained based on the available data in this study, even though JIA disease control and/or chronic inflammation may be implicated to some extent.

IgE-Dependent Food Sensitisation and Its Role in Clinical and Laboratory Presentation of Paediatric Inflammatory Bowel Disease

The rising prevalence of inflammatory bowel disease (IBD) and food allergies and their partially overlapping mechanisms such as microbiome diversity reduction raise questions about the role of allergies in IBD. While data on their comorbidity are available, analysis of IgE-sensitization's influence on the clinical presentation of IBD is lacking and is the aim of this study. Histories of 292 children with newly diagnosed IBD (173 cases of ulcerative colitis, 119 cases of Crohn's disease) were analyzed. Disease age of onset, activity, location, behaviour, and anthropometric and laboratory parameters were tested for its dependence on the presence of chosen IgE sensitization markers. A.o. Chi2, OR and phi coefficient were assessed. In Crohn's disease (CD), elevated total IgE (tIgE) correlated with weight loss, rectal bleeding, ASCA IgG positivity (φ = 0.19 for all) and negatively correlated with complicated disease behaviour (φ = -0.19). TIgE > 5 × reference range correlated with being underweight (φ = 0.2), ASCA IgG positivity (φ = 0.3), ASCA double (IgA and IgG) positivity (φ = 0.25) and elevated total IgG (φ = 0.18). The presence of specific IgEs (sIgE) correlated with extraintestinal manifestations of IBD (φ = 0.19): Egg white sIgE correlated with upper GI involvement (L4b) (φ = 0.26), severe growth impairment (φ = 0.23) and colonic mucosal eosinophilia (φ = 0.19). In ulcerative colitis, decreased IgA correlated with egg white sIgE (φ = 0.3), as well as the presence of any (φ = 0.25) or multiple sIgEs (φ = 0.2); the latter correlated also with elevated IgG (φ = 0.22), fever (φ = 0.18), abdominal pain (φ = 0.16) and being underweight (φ = 0.15). Cow's milk sIgE correlated positively with growth impairment (φ = 0.15) and elevated IgG (φ = 0.17) and negatively with extensive colitis (φ = -0.15). Pancolitis correlated negatively with sIgE presence (φ = -0.15). In summary, single moderate and numerous weak but interesting relationships were observed.

Crohn's Disease-Like Features in a Patient With IgE and Selective IgG1 and IgG3 Deficiency

We report a 19-year-old male with congenital, combined deficiency of immunoglobulin (Ig) E and 2/4 subclasses of IgG (G1, G3) and chronic diarrhea. He presented at six years of age with chronic recurrent diarrhea responsive to immunoglobulin treatment. Initially, it was considered of infectious origin. However, at the age of 14 years, ileocolonoscopy and magnetic resonance enterography (MRE) were performed, and they showed a mild, limited, non-specific, terminal ileitis with increased eosinophil count on histology. A diagnosis of possible eosinophilic gastroenteritis was made, and budesonide was administered with temporary relief. However, at the age of 19 years, repeat ileocolonoscopy showed multiple ulcers in the terminal ileum and aphthous ulcers in the cecum, and repeat MRE demonstrated extensive ileal involvement. Esophagogastroduodenoscopy demonstrated the involvement of the upper GI tract with aphthous ulcers. Subsequently, gastric, ileal, and colonic biopsies revealed Ziehl-Neelsen-negative, non-caseating granulomas. We hereby report the first case of IgE and selective IgG1 and IgG3 deficiency complicated with Crohn's disease-like extensive GI involvement.

Salivary IgA and IgG Antibody Responses against Periodontitis-Associated Bacteria in Crohn's Disease

Elevated serum immunoglobulin (Ig) antibody levels are observed in Crohn's disease patients. The aim of this study was to evaluate the salivary IgA and IgG antibody levels against Porphyromonas gingivalis, Tannerella forsythia, Aggregatibacter actinomycetemcomitans, and Prevotella intermedia in Crohn's disease patients. Eighty-eight participants (47 Crohn's disease patients and 41 systemically healthy age- and gender-matched controls) were included in the study. Oral and medical health statuses were recorded and salivary samples were collected. Salivary P. gingivalis, T. forsythia, A. actinomycetemcomitans, and P. intermedia carriage were analyzed with DNA sequencing technique, salivary levels of IgG1, IgG2, IgG3, IgG4, and IgM were measured with the Luminex^® xMAP™ technique, and salivary IgA and IgG antibody levels against P. gingivalis, T. forsythia, A. actinomycetemcomitans, and P. intermedia were detected by ELISA. As result, higher salivary IgG2 (p = 0.011) and IgG3 (p = 0.006), P. gingivalis IgA (p < 0.001), A. actinomycetemcomitans IgG (p = 0.001), and P. intermedia IgG (p < 0.001) antibody levels were detected in the Crohn's disease group compared to the controls. Salivary P. gingivalis carriage was lower in the Crohn's disease group in comparison to the controls (p = 0.024). In conclusion, salivary IgA antibody responses against P. gingivalis and IgG antibody responses against P. intermedia have independent associations with Crohn's disease.

Salivary IgA subtypes as novel disease biomarkers in systemic lupus erythematosus

Introduction

Immunoglobulin A (IgA) is the main antibody isotype in body fluids such as tears, intestinal mucous, colostrum, and saliva. There are two subtypes of IgA in humans: IgA1, mainly present in blood and mucosal sites, and IgA2, preferentially expressed in mucosal sites like the colon. In clinical practice, immunoglobulins are typically measured in venous or capillary blood; however, alternative samples, including saliva, are now being considered, given their non-invasive and easy collection nature. Several autoimmune diseases have been related to diverse abnormalities in oral mucosal immunity, such as rheumatoid arthritis, Sjogren's syndrome, and systemic lupus erythematosus (SLE).

Methods

We decided to evaluate the levels of both IgA subtypes in the saliva of SLE patients. A light chain capture-based ELISA measured specific IgA1 and IgA2 levels in a cohort of SLE patients compared with age and gender-matched healthy volunteers.

Results

Surprisingly, our results indicated that in the saliva of SLE patients, total IgA and IgA1 subtype were significantly elevated; we also found that salivary IgA levels, particularly IgA2, positively correlate with anti-dsDNA IgG antibody titers. Strikingly, we also detected the presence of salivary anti-nucleosome IgA antibodies in SLE patients, a feature not previously reported elsewhere.

Conclusions

According to our results and upon necessary validation, IgA characterization in saliva could represent a potentially helpful tool in the clinical care of SLE patients with the advantage of being a more straightforward, faster, and safer method than manipulating blood samples.

Liver-side of inflammatory bowel diseases: Hepatobiliary and drug-induced disorders

Hepatobiliary disorders are among the most common extraintestinal manifestations in inflammatory bowel diseases (IBD), both in Crohn’s disease and ulcerative colitis (UC), and therefore represent a diagnostic challenge. Immune-mediated conditions include primary sclerosing cholangitis (PSC) as the main form, variant forms of PSC (namely small-duct PSC, PSC-autoimmune hepatitis overlap syndrome and IgG4-related sclerosing cholangitis) and granulomatous hepatitis. PSC is by far the most common, presenting in up to 8% of IBD patients, more frequently in UC. Several genetic foci have been identified, but environmental factors are preponderant on disease pathogenesis. The course of the two diseases is typically independent. PSC diagnosis is based mostly on typical radiological findings and exclusion of secondary cholangiopathies. Risk of cholangiocarcinoma is significantly increased in PSC, as well as the risk of colorectal cancer in patients with PSC and IBD-related colitis. No disease-modifying drugs are approved to date. Thus, PSC management is directed against symptoms and complications and includes medical therapies for pruritus, endoscopic treatment of biliary stenosis and liver transplant for end-stage liver disease. Other non-immune-mediated hepatobiliary disorders are gallstone disease, whose incidence is higher in IBD and reported in up to one third of IBD patients, non-alcoholic fatty liver disease, pyogenic liver abscess and portal vein thrombosis. Drug-induced liver injury (DILI) is an important issue in IBD, since most IBD therapies may cause liver toxicity; however, the incidence of serious adverse events is low. Thiopurines and methotrexate are the most associated with DILI, while the risk related to anti-tumor necrosis factor-α and anti-integrins is low. Data on hepatotoxicity of newer drugs approved for IBD, like anti-interleukin 12/23 and tofacitinib, are still scarce, but the evidence from other rheumatic diseases is reassuring. Hepatitis B reactivation during immunosuppressive therapy is a major concern in IBD, and adequate screening and vaccination is warranted. On the other hand, hepatitis C reactivation does not seem to be a real risk, and hepatitis C antiviral treatment does not influence IBD natural history. The approach to an IBD patient with abnormal liver function tests is complex due to the wide range of differential diagnosis, but it is of paramount importance to make a quick and accurate diagnosis, as it may influence the therapeutic management.