IL-38 in Behçet's disease: Gene expression in bronchoalveolar lavage from patients having pulmonary involvement

The etiological complexity of Behçet disease (BD), an immune-mediated rare form of vasculitis characterized by multi-organ involvement, is still elusive due to an incomplete understanding of the synergy between genetic susceptibility, environmental triggers, and an abnormal immune response. The diagnosis of BD relies on clinical symptoms. Lung inflammatory disorders are severe conditions of patients with BD, here we focus on the expression of biomarkers in BD patients with pulmonary manifestations. Aiming to identify additional discriminating biomarker patterns, we measured and compared protein and gene expression of IL-38 and a broad panel of selected genes in bronchoalveolar cells of patients suffering from BD with and without pulmonary involvement compared to controls. ELISA and RT-PCR analysis were applied. The first principal analysis highlighted decreased IL-38 level in BD patients compared to Rheumatoid Arthritis (RA) patients and controls: BD patients expressed lower IL-38 levels, particularly in cases with pulmonary involvement. The area under the curve (AUC) of the receiver-operating characteristic curve showed that IL-38 may be an eventual biomarker for BD. Co-cultured recombinant IL-38 and stimulated memory PBMCs of active BD, were able to suppress IL-17 and NLRP3 inflammasome and ameliorate the secretion of IL-10 and TGFβ. Transcription factors of the IL-1 family (IL-1β, IL-18, IL-32, IL-33 and IL-37) along with IFN-γ, IL-17, RORγt, Foxp3, TGFβ, IL-10 and NLRP3 inflammasome were the parameters that are the main contributor to the segregation between BD with and without lung involvement. Our results indicate that IL-38 might be involved in the pathogenesis of BD and the combined gene expression in BAL suggests distinct mechanisms governing the inflammatory disorders in the lung.

Identification and Characterization of Phytohemagglutinins from White Kidney Beans (Phaseolus vulgaris L., var. Beldia) in the Rat Small Intestine

Although kidney bean (Phaseolus vulgaris L.) lectin toxicity is widely known, its effects in the gastrointestinal tract require further study. This investigation aimed to identify and characterize phytohemagglutinins (PHAs) in the small intestine and sera of rats following oral challenge with ground white beans. Twenty young, adult male rats were divided randomly into two groups of 10 animals each. The control group underwent gavage with a suspension of 300 mg of rodent pellet flour. The experimental group was administered a 300 mg Beldia bean flour suspension (BBFS). After 10 days of daily treatment, jejunal rinse liquid (JRL) and ileum rinse liquid and secretions, as well as sera, were collected. All biological fluids were screened for lectin reactivity using competitive inhibition ELISA, Ouchterlony double immunodiffusion, and immunoelectrophoresis techniques. The results revealed the presence of immunogenic intraluminal PHAs 3-4 h after the oral intake of the BBFS in the JRLs as well as in the jejunal and ileal secretions; however, no PHA was detectable in the rat sera. Ingestion of raw Beldia beans may lead to interaction between PHAs and the mucosa of the small intestine, potentially resulting in an inflammatory response.

Effect of White Kidney Beans (Phaseolus vulgaris L. var. Beldia) on Small Intestine Morphology and Function in Wistar Rats

The chronic ingestion of raw or undercooked kidney beans (Phaseolus vulgaris L.) causes functional and morphological derangement in various tissues. The major objectives of this study were to investigate the gavage effects of a raw Beldia bean variety that is widely consumed in Tunisia, on the small intestine morphology and jejunal absorption of water, electrolytes, and glucose in Wistar rats. Twenty young male rats were randomly divided into two groups of 10 rats. The first group served as the control and was gavaged with 300 mg of a rodent pellet flour suspension (RPFS), whereas the second experimental group was challenged with 300 mg of a Beldia bean flour suspension (BBFS) for 10 days. Histological studies were performed using light and electron microcopy. The intestinal transport of water, sodium, potassium, and glucose was studied by perfusing the jejunal loops of the small bowels in vivo. The feeding experiments indicated that BBFS did not affect weight gain. Histomorphometric analyses showed that the villus heights, crypt depths, and crypt/villus ratios in the jejunum and ileum were greater in the BBFS-fed rats than controls. Electron microscopy studies demonstrated that the rats exposed to RPFS exhibited intact intestinal tracts; however, the BBFS-treated rats demonstrated intestinal alterations characterized by abnormal microvillus architectures, with short and dense or long and slender features, in addition to the sparse presence of vesicles near the brush border membrane. BBFS administration did not significantly affect glucose absorption. However, significant decreases were observed in water and electrolyte absorption compared with the uptake of the controls. In conclusion, raw Beldia beans distorted jejunum morphology and disturbed hydroelectrolytic flux.

CCR2-64I polymorphism is associated with Non-Small Cell Lung Cancer in Tunisian patients

Single nucleotide polymorphism (SNPs) in genes coding for chemokines may be associated with some cancer. The purpose of this study was to investigate the impact of CCR2-64I and CXCL12-3'A SNPs on the susceptibility and the clinicopathological characteristics of NSCLC (Non-Small Cell Lung Cancer) in the Tunisian population. 170 NSCLC patients and 225 healthy controls screened by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis were enrolled. A significant association for the homozygous genotype CCR2 64I/64I with lung cancer risk was observed (P=0.004). An increased significant frequency of the -64I allele (P=0.0006) was noted in the patient's group. Clinical analysis indicated a positive association of the -64I allele among squamous cell lung carcinoma patients (P=0.003). The CCR2 mRNA extracted from peripheral blood mononuclear cells (PBMC) was found highly expressed in NSCLC patients compared to controls. The same higher levels were found in patients carrying the CCR2 64I/64I genotype. No significant association was retrieved with CXCL12-3'A polymorphism. In conclusion, our results revealed that the subjects with -64I allele of CCR2-64I gene polymorphism, expressed a significantly higher risk for NSCLC risk without influence on its pathological progression.

Toxicity Assessment of Common Beans (Phaseolus vulgaris L.) Widely Consumed by Tunisian Population

This research aimed at assessing the content and the functional properties of phytohemagglutinin (PHA) in different varieties of beans widely consumed in Tunisia through soaking, cooking, autoclaving, germination, and their combinations. This study was carried out on three varieties of white beans grown in different localities of Tunisia, namely Twila, Coco, and Beldia, as well as on imported and local canned beans. All bean samples underwent biochemical and immunological evaluation by employing several techniques such as indirect competitive enzyme-linked immunosorbent assay (ELISA), hemagglutinating assay, Ouchterlony double immunodiffusion, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Biochemical and immunological analyses indicated that raw dry beans contained a considerable amount of proteins and PHAs. ELISA demonstrated that soaking, either in plain water or in alkaline solution, caused an increase in the concentration of PHA. A slight increase of PHA was produced equally by germination during 4 days in all bean varieties. Cooking or autoclaving of presoaked beans resulted in a complete disappearance of PHA. ELISA test also proved that both imported and local canned beans contained fingerprints of PHA. Hemagglutination assays showed that not only cooked and autoclaved presoaked beans lacked the ability to agglutinate red blood cells but also autoclaved unsoaked beans did. In agar gel immunodiffusion using rabbit anti-PHA serum, raw, soaked, cooked unsoaked, and sprouted beans gave precipitin arc reactions, indicating that PHA existed in immunoreactive form in the tested seeds. SDS-PAGE electrophoretograms showed protein isolates of Twila and Beldia beans to have different profiles through soaking, cooking, and autoclaving processes. This work revealed that the combination of soaking and cooking/autoclaving was the best way in reducing PHA content and its activity in all bean varieties when compared with germination.

Tumor necrosis factor gene polymorphisms in Tunisian patients with non-small cell lung cancer

BACKGROUND

Lung cancer (LC) is one of the most lethal malignant disorders; it is generally divided into two groups: small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). In our present study we have been interested to NSCLC. Several approaches were adopted to study the etiology or pathophysiology of this disease. As recent reports have focused on the genetic susceptibility to this disease, with many candidate genes studied, we chose TNF in view of the major role it plays in the immune pro inflammatory system and its association with increased risk of a variety of human cancers. We have investigated three polymorphisms in the promoter region of the TNFalpha gene (-308 G/A and -238 G/A) and TNFbeta + 252A > G for their susceptibility to non-small cell lung cancer (NSCLC) in Tunisian population.

METHODS

We compared the distribution of these polymorphisms between 133 NSCLC patients and 174 healthy controls using a polymerase chain reaction restriction fragment length-polymorphism (PCR-RFLP) analysis. The frequencies of the two TNFalpha (-238 and -308) "A" alleles were significantly higher in NSCLC patients than in healthy controls respectively (p = 0.01; OR = 1.92; 95% CI 1.14 - 3.23 and p = 0.0000008; OR = 3.65; 95% CI 2.12 - 6.30), whereas the frequency of the TNFbeta + 252 G allele was approximately similar in the two compared groups.

RESULTS

This study supports a relationship between TNFalpha -238G/A and TNFalpha -308G/A polymorphisms and the susceptibility to lung cancer. Contrary to other studies, the -308 A and -238A alleles have an inductive action on lung cancer development and progression in our Tunisian population.

CONCLUSIONS

This study indicates that the TNFalpha -308G > A and TNFalpha -238G > A would be associated with increased susceptibility to lung cancer but no significant association was found in TNFbeta + 252A > G polymorphism.

Association of vitamin D receptor gene polymorphisms with susceptibility to asthma in Tunisian children: A case control study

BACKGROUND

Vitamin D and its nuclear receptor (VDR) are linked to asthma in a genetic and immunologic basis. Polymorphisms in the VDR gene may alter the actions of vitamin D and then influence the development and the severity of asthma.

AIMS

We aimed at elucidating the genetic association of VDR gene polymorphisms with susceptibility to asthma in Tunisian children and with serum vitamin D levels.

METHODS

The study included 155 patients recruited from Abderrahmen MAMI hospital in Tunisia and two hundred twenty five healthy individuals matched with patients in age and sex for comparison. VDR genotypes were determined by PCR-RFLP method using endonuclease FokI, BsmI, TaqI and ApaI and vitamin D was assessed with a radioimmunoassay kit.

RESULTS

The distribution of genotype frequencies differed significantly between asthmatics and controls (FokI: P=0.04; BsmI: P=0.006; TaqI: P=0.006). Haplotype analyses revealed a significant association between bAt and bat haplotypes and asthma (P=0.00076, P=0.016). When patients were stratified according to atopic status and stage of severity, no significant association was detected with VDR variants. No association was found between VDR SNPs and serum 25-hydroxyvitamin D levels.

CONCLUSION

Our study shows a relation between VDR gene polymorphisms and susceptibility to asthma in children.

Vitamin D modulates peripheral immunity in patients with Behçet's disease

BACKGROUND AND OBJECTIVES

There is little knowledge about clinical and immunological variables associated with vitamin D insufficiency in inflammatory diseases. We sought to investigate disease variables associated with vitamin D levels in patients with Behçet's disease (BD) and its interaction with inflammatory responses.

METHODS

One hundred and sixty BD patients (102 patients in active stage) were enrolled in a study assessing the relationship between serum vitamin D concentrations and disease activity. As control diseases we studied 22 Rheumatoid arthritis (RA) and 30 multiple sclerosis (MS) patients. Serum concentrations of vitamin D were assayed with a radioimmunoassay kit. To assess the correlation between inflammatory mediators, immune cell expression and vitamin D, 20 active BD patients and 18 healthy controls were investigated: T-cell subsets and Treg cells were quantified by flow cytometry. Th1/Th2 ratio and Th17 were studied by intracytoplasmic cytokines expression (IFN-γ, IL-4, IL-10 and IL-17).

RESULTS

Decreased levels of vitamin D were observed in active BD patients compared to patients in the inactive stage and to healthy controls (p=0.0246; p=0.0001). A low significant difference was observed between inactive BD and healthy controls (p=0.004). Active BD expressed higher vitamin D levels than RA (p=0.007) and MS (p=0.044) patients (p=0.0238). In active BD, vitamin D levels were correlated with CRP and ESR. Serum levels of vitamin D correlated positively with the number of Treg cells (r=0.640; p=0.0024). The IFN-γ/IL-4 ratio (Th1/Th2) was inversely correlated with serum 25(OH)D levels (r=-0.599; p=0.0053).

CONCLUSIONS

Active BD was associated with lower serum Vitamin D levels. Our results showed that low levels of vitamin D were associated with a decrease in Treg cells and a skewing of the Th1/Th2 balance towards Th1. These findings suggest that vitamin D is an important promoter of T cell regulation in vivo in BD patients. As suggested in other inflammatory/autoimmune diseases, vitamin D may modulate inflammatory mediators.