Defective expression of scavenger receptors in celiac disease mucosa

Clearing the Path: Exploring Apoptotic Cell Clearance in Inflammatory and Autoimmune Disorders for Therapeutic Advancements

Inflammatory and autoimmune disorders, characterized by dysregulated immune responses leading to tissue damage and chronic inflammation, present significant health challenges. This review uniquely focuses on efferocytosis-the phagocyte-mediated clearance of apoptotic cells-and its pivotal role in these disorders. We delve into the intricate mechanisms of efferocytosis' four stages and their implications in disease pathogenesis, distinguishing our study from previous literature. Our findings highlight impaired efferocytosis in conditions like atherosclerosis and asthma, proposing its targeting as a novel therapeutic strategy. We discuss the therapeutic potential of efferocytosis in modulating immune responses and resolving inflammation, offering a new perspective in treating inflammatory disorders.

Evaluation of crypt apoptotic bodies and apoptotic indices in pediatric celiac disease by routine staining and H2AX immunostaining

Celiac disease (CD) is an immune-mediated disorder with premature apoptosis occurring along the entire crypt-villous axis. H2AX is the end product of the intrinsic apoptotic pathway. This is the first study to assess apoptotic body counts (ABC) by H&E and apoptotic indices (AI) by immunohistochemistry (IHC) in pediatric CD. The aim of the current study was to evaluate ABC in pediatric patients with CD prior to and following institution of a gluten free diet (GFD). Sixty-three pediatric endoscopic duodenal samples were assessed and divided into three groups. A total of 21 samples from treatment naïve CD patients, 21 from the same patients after instituting a GFD, and 21 from non-celiac patients as a control group. Histopathological evaluation of ABC by H&E, and immunohistochemistry assessment of apoptotic indices (AI) by H2AX antibody were performed. The mean maximum ABC and AI were significantly higher in treatment naïve CD than in GFD and control samples. These values were also significantly higher in treatment naïve Marsh 3C (flat) than in Marsh 1, 2, 3A, and 3B (non-flat) CD cases. GFD samples with persistent flat lesions had significantly higher ABC and AI than GFD non-flat cases. ROC analysis of the mean maximum ABC and AI of treatment naïve CD cases had a statistically significant predictive potential for persistent villous atrophy at a cut-off level ⩾6.61 (P = 0.008) and ⩾105.4 (P = 0.003), respectively. Histopathological evaluation of crypt apoptotic bodies could provide predictive potential for continued villous atrophy following GFD.

The Role of Monocytes and Macrophages in Autoimmune Diseases: A Comprehensive Review

Monocytes (Mo) and macrophages (Mϕ) are key components of the innate immune system and are involved in regulation of the initiation, development, and resolution of many inflammatory disorders. In addition, these cells also play important immunoregulatory and tissue-repairing roles to decrease immune reactions and promote tissue regeneration. Several lines of evidence have suggested a causal link between the presence or activation of these cells and the development of autoimmune diseases. In addition, Mo or Mϕ infiltration in diseased tissues is a hallmark of several autoimmune diseases. However, the detailed contributions of these cells, whether they actually initiate disease or perpetuate disease progression, and whether their phenotype and functional alteration are merely epiphenomena are still unclear in many autoimmune diseases. Additionally, little is known about their heterogeneous populations in different autoimmune diseases. Elucidating the relevance of Mo and Mϕ in autoimmune diseases and the associated mechanisms could lead to the identification of more effective therapeutic strategies in the future.

Celiac Disease and Concomitant Conditions: A Case-based Review

Celiac disease is a chronic autoimmune disease with genetic predisposition, triggered by the ingestion of gluten. It has a wide range of clinical manifestations ranging from asymptomatic forms to classic presentation of malabsorption with diarrhea and abdominal cramps. Celiac disease can also present with several other concomitant disorders (at the time of diagnosis or during the course of celiac disease) such as: type 1 diabetes, inflammatory bowel disease, rheumatoid arthritis, thyroid disorders, nutritional deficiencies, and gram-negative sepsis. We present a 57-year-old female with past medical history of rheumatoid arthritis, who presented to the emergency department with a complaint of chronic diarrhea, complicated by gram-negative sepsis. The family history of the patient was significant for celiac disease, type 1 diabetes, and rheumatoid arthritis. The patient was closely monitored and treated appropriately. In this case-based review, we explore different associated conditions of celiac disease in the literature, as well as the patient's risk of developing malignancy.

Shared Genetic Factors Involved in Celiac Disease, Type 2 Diabetes and Anorexia Nervosa Suggest Common Molecular Pathways for Chronic Diseases

Background and Objectives

Genome-wide association studies (GWAS) have identified several genetic regions involved in immune-regulatory mechanisms to be associated with celiac disease. Previous GWAS also revealed an over-representation of genes involved in type 2 diabetes and anorexia nervosa associated with celiac disease, suggesting involvement of common metabolic pathways for development of these chronic diseases. The aim of this study was to extend these previous analyses to study the gene expression in the gut from children with active celiac disease.

Material and Methods

Thirty six target genes involved in type 2 diabetes and four genes associated with anorexia nervosa were investigated for gene expression in small intestinal biopsies from 144 children with celiac disease at median (range) age of 7.4 years (1.6–17.8) and from 154 disease controls at a median (range) age 11.4.years (1.4–18.3).

Results

A total of eleven of genes were differently expressed in celiac patients compared with disease controls of which CD36, CD38, FOXP1, SELL, PPARA, PPARG, AGT previously associated with type 2 diabetes and AKAP6, NTNG1 with anorexia nervosa remained significant after correction for multiple testing.

Conclusion

Shared genetic factors involved in celiac disease, type 2 diabetes and anorexia nervosa suggest common underlying molecular pathways for these diseases.

Rheumatoid arthritis-celiac disease relationship: joints get that gut feeling

Rheumatoid arthritis (RA) and celiac disease (CD) belong to the autoimmune disease family. Despite being separate entities they share multiple aspects. Epidemiologically they share comparable incidence environmental influences, associated antibodies and a recent incidental surge. They differ in their HLA pre-dispositions and specific predictive and diagnostic biomarkers. At the clinical level, celiac disease exhibits extra-intestinal rheumatic manifestations and RA gastrointestinal ones. Small bowel pathology exists in rheumatic patients. A trend towards responsiveness to a gluten free diet has been observed, ameliorating celiac rheumatic manifestations, whereas dietary interventions for rheumatoid arthritis remain controversial. Pathophysiologically, both diseases are mediated by endogenous enzymes in the target organs. The infectious, dysbiotic and increased intestinal permeability theories, as drivers of the autoimmune cascade, apply to both diseases. Contrary to their specific HLA pre-disposition, the diseases share multiple non-HLA loci. Those genes are crucial for activation and regulation of adaptive and innate immunity. Recently, light was shed on the interaction between host genetics and microbiota composition in relation to CD and RA susceptibility, connecting bugs and us and autoimmunity. A better understanding of the above mentioned similarities in the gut-joint inter-relationship, may elucidate additional facets in the mosaic of autoimmunity, relating CD to RA.

Inflammatory Cytokine-Mediated Regulation of Thrombospondin-1 and CD36 in Conjunctival Cells

PURPOSE

Increased expression of transforming growth factor-β2 (TGF-β2) is reported in the conjunctiva of dry eye patients with no increase of anti-inflammatory activity of TGF-β2. Our aim was to compare the expression of molecules involved in TGF-β2 activation, thrombospondin-1 (TSP-1) and CD36, during murine and human conjunctival inflammation.

METHODS

Human conjunctival tissue from cadaveric donors, human conjunctival epithelial primary cells and fibroblasts, and murine conjunctivas were immunostained for TSP-1, CD36, or TGF-β2. Inflamed conjunctival tissues were obtained from C57BL/6 wild-type (WT) mice induced to develop experimental dry eye (EDE) with 10 days of desiccating conditions and scopolamine injections and TSP-1-deficient (TSP1(-/-)) mice, which spontaneously develop Sjögren's syndrome-associated conjunctival inflammation with age. Immunostaining intensities were compared using ImageJ software. Cultures of human conjunctival fibroblasts were stimulated with IL-1β and both secreted protein and message levels of TSP-1, CD36, and TGF-β2 were analyzed.

RESULTS

TSP-1 and CD36 were detectable in human and murine conjunctival tissues as well as primary conjunctival epithelial cells and fibroblasts. Increased conjunctival immunostaining of TGF-β2 and reduced CD36 were detected in EDE mice compared with WT mice. Interestingly, increased TGF-β2 and CD36 conjunctival immunostaining was detected in TSP1(-/-) mice. The expression of TSP-1 and CD36 was downregulated in IL-1β-stimulated conjunctival fibroblasts at both the protein and message level, while active TGF-β2 was undetected.

CONCLUSIONS

The absence or reduced expression of either of the molecules involved in TGF-β2 activation supports proinflammatory conditions in the conjunctiva. Changes in TSP-1 and CD36 may serve as potential biomarkers of conjunctival inflammation.