In-vitro characterization of novel and functional regulatory SNPs in the promoter region of IL2 and IL2R alpha in a Gabonese population

Circular RNA circLOC101928570 suppresses systemic lupus erythematosus progression by targeting the miR-150-5p/c-myb axis

Background

Accumulating evidence supports the implication of circular RNAs (circRNAs) in systemic lupus erythematosus (SLE). However, little is known about the detailed mechanisms and roles of circRNAs in the pathogenesis of SLE.

Methods

Quantitative real-time PCR was used to determine the levels of circLOC101928570 and miR-150-5p in peripheral blood mononuclear cells of SLE. Overexpression and knockdown experiments were conducted to assess the effects of circLOC101928570. Fluorescence in situ hybridization, RNA immunoprecipitation, luciferase reporter assays, Western blot, flow cytometry analysis and enzyme-linked immunosorbent assay were used to investigate the molecular mechanisms underlying the function of circLOC101928570.

Results

The results showed that the level of circLOC101928570 was significantly downregulated in SLE and correlated with the systemic lupus erythematosus disease activity index. Functionally, circLOC101928570 acted as a miR-150-5p sponge to relieve the repressive effect on its target c-myb, which modulates the activation of immune inflammatory responses. CircLOC101928570 knockdown enhanced apoptosis. Moreover, circLOC101928570 promoted the transcriptional level of IL2RA by directly regulating the miR-150-5p/c-myb axis.

Conclusion

Overall, our findings demonstrated that circLOC101928570 played a critical role in SLE. The downregulation of circLOC101928570 suppressed SLE progression through the miR-150-5p/c-myb/IL2RA axis. Our findings identified that circLOC101928570 serves as a potential biomarker for the diagnosis and therapy of SLE.

PTPN22 gene and IL2RA rs11594656, rs2104286 gene variants: additional insights of polygenic single-nucleotide polymorphisms’ pattern among Egyptian children with type 1 diabetes

Background

Type 1 diabetes mellitus (T1D) results from environmental and genetic factors.

We aimed to investigate the distribution of PTPN22, IL2RA rs11594656, and rs2104286 variants and its association with T1D in children.

A case-control study conducted on 100 diabetic patients and 100 control children. PTPN22 gene, IL2RA rs11594656, and rs2104286 polymorphisms study were done by PCR followed by restriction fragment length polymorphism (RFLP) assay.

Results

T allele of PTPN22 gene was presented more frequently 47% in patient group versus 30% in controls, while C allele was 53% in the diabetic group versus 70% in controls showing a statistically significant difference between patient and control groups. Similarly, TT 1858 genotype was found in higher frequency with a statistically significant difference in favor of T1D patients (p = 0.038), OR (CI 95% 3.16 (1.28–7.09).

For IL2RA rs11594656 polymorphism, the frequency of TT, TA, and AA in patients at percentages of 20%, 60%, and 20% versus 4%, 60%, and 36% in controls respectively showed significant difference (p = 0.045). Also, T allele was detected more in patients group as evidenced by p = 0.059, OR (95% CI) of 2.38(1.49–6.12). Whereas, IL2RA rs2104286 polymorphism revealed a difference of otherwise non-statistical significance (p = 0.091). Those who harbored homozygous pattern of both IL2RA polymorphisms frequently had DKA and high mean HbA1C values.

Conclusion

PTPN22 (C1858T) and IL2RA rs11594656 polymorphisms increased the risk of T1DM development, while IL2RA rs2104286 polymorphism did not display any significant association among children with T1D. Having more than one risk allele could affect progression and control of T1D.

FOXO3A regulatory polymorphism and susceptibility to severe malaria in Gabonese children

The clinical course of malaria varies between affected individuals and host genetic factors have been shown to influence the outcome of malaria. The role of FOXO3-driven pathway in modulating inflammatory responses, including mediation of distinct functions of regulatory T effector cell populations (Tregs) by the transcription factor FOXO3, has recently been recognized. We aimed to study possible associations of a non-coding polymorphism in intron 2 of the FOXO3A gene (rs12212067T>G) that was shown earlier to modulate the FOXO3 expression and to be associated with the prognosis of distinct inflammatory and infectious diseases. The FOXO3A polymorphism rs12212067T>G was genotyped by direct sequencing in a group of Gabonese children with confirmed Plasmodium falciparum malaria. Severe cases of malaria were compared with asymptomatic/mild cases. The FOXO3A variant rs12212067T>G was associated with the phenotype of severe malaria, but not with asymptomatic/mild malaria (allelic model: OR = 1.54, 95 % CI = 1.15-2.05, P = 0.0028; dominant model: OR = 1.94, 95 % CI = 1.36-2.77, P = 0.0002). The FOXO3A variant rs12212067T>G is associated with increased inflammatory responses to Plasmodium falciparum malaria, indicating a role of the FOXO3-dependent pathway in malaria.

Analysis of genetic variants in the IL4 promoter and VNTR loci in Indian patients with Visceral Leishmaniasis

Visceral Leishmaniasis (VL) is the most severest form of Leishmaniasis and resistance to infection is mediated by cellular immune responses. Interleukin 4 (IL-4) orchestrates of Th2 and Th1 immune responses during infections. In this study, we aimed to investigate possible association between three functional IL-4 polymorphisms -590C/T (rs2243250), -34C/T (rs2070874) and 70bp VNTR (rs79071878 in intron3) with VL in an Indian cohort comprising of 197 VL patients and 193 healthy controls. The three investigated IL-4 polymorphisms were in strong linkage disequilibrium. The investigated IL-4 alleles, genotypes and the reconstructed haplotypes were not significantly distributed between the VL patients and healthy controls. Our study signifies no possible association of functional IL-4 polymorphisms with Indian VL and postulate other vital genes involved in the IL-4 pathway may provide genetic clues to elucidate of IL-4 regulation and immune-pathogenesis during VL.