Association of Hepatitis A exposure and TIM-1 with childhood allergic asthma

Local and systemic autoimmune manifestations linked to hepatitis A infection

Hepatitis A virus (HAV) represents a global burdening infectious agent causing in the majority of cases a self-limiting acute icteric syndrome, the outcome is related to the hepatic substrate and the potential pre-existing damage, whereas a plethora of extra-hepatic manifestations has also been reported. Despite the absence of post- HAV chronicity it has been associated with an additional burden on existing chronic liver diseases. Moreover, the induced immune response and the antigenic molecular mimicry are considered as triggering factors of autoimmunity with regional and distal impact. Diseases such as autoimmune hepatitis, Guillain-Barré syndrome, rheumatoid arthritis, Still's syndrome, Henoch-Schönlein purpura, autoimmune hemolytic anemia, antiphospholipid syndrome, systematic lupus erythematosus or cryoglobulinemic vasculitis have been described in patients with HAV infection. Although the exact mechanisms remain unclear, this review aims to accumulate and clarify the pathways related to this linkage.

HAVCR1 Affects the MEK/ERK Pathway in Gastric Adenocarcinomas and Influences Tumor Progression and Patient Outcome

The hepatitis A virus cellular receptor 1 (HAVCR1) gene as a sensitive and specific biomarker has been reported in various diseases. Especially, HAVCR1 overexpression promotes the development and progression of several human cancers. Hence, we aimed to detect the effects of HAVCR1 on gastric adenocarcinoma (GAC). We first determined the expression of HAVCR1 in GAC tissues compared with normal gastric tissues based on the Cancer Genome Atlas (TCGA) database using bioinformatics analysis methods. Then, we assessed the biological function of HAVCR1 in GAC cells using quantitative real-time reverse transcription-PCR (qRT-PCR), western blot, cell counting kit-8- (CCK-) 8, colony formation assay, wound healing assay, and transwell assay. Our results showed that HAVCR1 expression was upregulated in GAC tissues and positively associated with poor survival. Loss-of-function analyses indicated that knockdown of HAVCR1 inhibited the proliferation, colony formation, migration, and invasion of GAC cells. Furthermore, reduction of HAVCR1 in GAC cells can decrease the expression of phosphorylated MEK/ERK. These findings suggested that HAVCR1 may represent a potential biomarker for GAC prognosis, as well as a novel therapeutic target for GAC treatment.

Genetic polymorphisms of rs9313422 G>C and rs41297579 G>A at the promoter of TIM-1 gene contribute to the risk of community-acquired pneumonia in children

OBJECTIVE

To investigate the association of genetic polymorphisms of rs9313422 G>C and rs41297579 G>A at the promoter of TIM-1 gene with the risk of community-acquired pneumonia (CAP) in children.

METHODS

A total of 112 children with CAP were included as the case group. Another 120 healthy children were enrolled as the control group. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was applied for the genotyping of rs9313422 G>C and rs41297579 G>A in the promoter region of TIM-1.

RESULTS

rs9313422 G>C was related to the risk of CAP in children under codominant model, dominant model, recessive model, and allele model. Besides, the A allele of rs41297579 G>A could increase the risk of CAP in children. Besides, the haplotype GA (rs9313422-rs41297579) and GG reduced the risk of children CAP, while haplotype CA had an elevated risk. rs9313422 G>C and rs41297579 G>A polymorphisms were both associated with the severity of CAP in children, and the rs9313422 G>C was also related to the ICU admission rate. In addition, patients carried with the mutant homozygotes of rs9313422 G>C and rs41297579 G>A showed higher levels of white blood cell (WBC), procalcitonin (PCT), and C-reactive protein (CRP) than the wild type and heterozygous genotypes carriers.

CONCLUSION

rs9313422 G>C and rs41297579 G>A polymorphisms in the promoter region of TIM-1 could increase the risk of CAP in children and showed a relation with inflammatory responses and severity.

Associations of TIM-1 Genetic Polymorphisms with Asthma: A Meta-analysis

PURPOSE

Recently, the roles of TIM-1 genetic polymorphisms in asthma have been extensively studied, with conflicting results. Therefore, we performed the present meta-analysis to better assess potential associations of TIM-1 genetic polymorphisms with asthma.

METHODS

Eligible articles were searched in PubMed, Medline, EMBASE, Google Scholar, and CNKI up to December 2016. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to detect any potential associations between TIM-1 genetic polymorphisms and asthma.

RESULTS

A total of 12 articles including 3120 asthma patients and 2825 control subjects were analyzed. The overall and subgroup analyses revealed that TIM-1-416G>C single nucleotide polymorphism was significantly associated with asthma for the Asian population in the codominant (G/G vs. G/C, p = 0.0003, OR 1.86, 95% CI 1.33-2.60) and dominant (G/G vs. G/C + C/C, p < 0.0001, OR 1.94, 95% CI 1.40-2.69) genetic models. Nevertheless, we failed to detect any significant associations between TIM-1-416G>C single nucleotide polymorphism and asthma in Caucasians. Additionally, according to our analyses, TIM-1 5383_5397 insertion/deletion polymorphism was not correlated with asthma in both Asians and Caucasians.

CONCLUSIONS

In conclusion, our findings suggest that TIM-1-416G>C single nucleotide polymorphism is associated with asthma susceptibility for the Asian ethnicity in certain genetic models. However, TIM-1 5383_5397 insertion/deletion polymorphism may not be correlated with the risk of asthma.

TIM-1 rs41297579 G>A (-1454) and TIM-4 rs7700944 gene polymorphisms as possible risk factor for rheumatoid arthritis: relation to activity and severity

This study was aimed to evaluate the impact of both TIM-1 rs41297579 G>A (-1454) and TIM-4 rs7700944 polymorphisms on susceptibility to rheumatoid arthritis (RA) in a cohort of Egyptian population and to evaluate for the first time their relation to activity, severity, disease-related disability and erosion. TIM-1 rs41297579 G>A (-1454) and TIM-4 rs7700944 gene polymorphisms were typed by RFLP for 128 patients with RA and 125 healthy controls. The A allele, A-containing genotypes (GA and AA) of the TIM-4 and GA haplotype were present with significant higher frequency in patients with RA than healthy controls (Pc  < 0.001). These findings suggest that the A allele, A-containing genotypes (GA and AA) and GA haplotype may be a susceptibility risk factor for RA [OR = 5.83 (3.6-9.4), OR = 9.41 (5.0-17.6) and OR = 4.21 (1.07-19.2), respectively]. No associations were found between TIM genotypes and disease activity, severity or presence of erosion. However, the RA patients with GA genotype of TIM-4 have higher grade of rheumatoid factor (RF) positivity (P = 0.018), and have worse disease-related disability (P = 0.007) and worse pain (0.025). TIM-4 rs7700944 and not TIM-1 rs41297579 G>A (-1454) is associated with RA in the present cohort of Egyptian and may be a risk factor for development of RA in Egyptian. Both SNPs have no effect on disease activity, severity or erosion. However, TIM-4 GA genotype is associated with higher grade of RF positivity and worse disease-related disability and pain.

Protective association of TIM1-1454G>a polymorphism with asthma in a North Indian population

PURPOSE

TIM1 is a key regulator of Th2-dominated immune responses, including allergy, asthma, autoimmunity, and response to the pathogens. They are mainly expressed by hepatocytes and lymphoid cells. Analysis of the sequence of TIM1 was found to have range of SNPs which increases the transcriptional activity of the TIM1 gene.

METHODS

A case-control study was conducted with a total of 964 subjects, including 483 healthy controls and 481 asthma patients in the present study. DNA samples were extracted from blood, and genotyping was done using polymerase chain reaction-restriction fragment length polymorphism method.

RESULTS

Statistical analysis revealed that both heterozygous (GA) as well as the mutant (AA) genotype of -1454G>A (rs41297579) polymorphism shows resistance toward asthma with OR = 0.74, 95 % CI (0.55-0.98), p = 0.029 and OR = 0.43, 95 % CI (0.28-0.65), p = 0.000, respectively. The mutant (A) allele was also found to be highly protective toward asthma with OR = 0.68, 95 % CI (0.56-0.82) p = 0.000. However, no statistical difference was found between the TIM1-416G>C (rs9313422) polymorphism and asthma patients (p > 0.05).

CONCLUSIONS

This is the first study conducted in India conferring -1454G>A polymorphism provides resistance toward asthma while lack of association was found between -416G>C polymorphism and asthma in the studied North Indian population.

Molecular biology and inhibitors of hepatitis A virus

Hepatitis A virus (HAV) is a faeco-orally transmitted picornavirus and is one of the main causes of acute hepatitis worldwide. An overview of the molecular biology of HAV is presented with an emphasis on recent findings. Immune evasion strategies and a possible correlation between HAV and atopy are discussed as well. Despite the availability of efficient vaccines, antiviral drugs targeting HAV are required to treat severe cases of fulminant hepatitis, contain outbreaks, and halt the potential spread of vaccine-escape variants. Additionally, such drugs could be used to shorten the period of illness and decrease associated economical costs. Several known inhibitors of HAV with various mechanisms of action will be discussed. Since none of these molecules is readily useable in the clinic and since the availability of an anti-HAV drug would be of clinical importance, increased efforts should be targeted toward discovery and development of such antivirals.

Pooled-analysis of the association between TIM-1 5383_5397 insertion/deletion polymorphism and asthma susceptibility

The T cell immunoglobulin (Ig) domain and mucin domain 1 (TIM-1) gene play an important role in pathogenesis of asthma. We investigate the association between the TIM-1 5383_5397 insertion/deletion polymorphism (rs45623443) and the risk of asthma in an asthma case-control study, and added these data to a literature-based meta-analysis. The TIM-1 5383_5397 insertion/deletion polymorphism genotype was analyzed in 156 asthma patients and 162 healthy subjects from Han Chinese population. We combined our data with that from previously published studies and performed a meta-analysis to evaluate the effect of the gene. Through regression model, we found no significant association for TIM-1 5383_5397 insertion/deletion polymorphism in our cohort. Meta-analysis, comprising a total of 1,577 asthma cases and 1,781 controls, revealed that no significant association between and asthma susceptibility was observed (OR = 0.99, 95 % CI = 0.83-1.20 for Ins vs. Del; OR = 1.01, 95 % CI = 0.74-1.37 for Ins/Ins vs. Ins/Del + Del/Del; OR = 0.96, 95 % CI = 0.78-1.18 for Ins/Ins + Ins/Del vs. Del/Del). The present meta-analysis suggested that TIM-1 5383_5397 insertion/deletion polymorphism may not substantially contribute to asthma susceptibility. However, gene-gene and gene-environment interaction effects and other considerations involving this polymorphism may exit.

TIM-family proteins inhibit HIV-1 release

Accumulating evidence indicates that T-cell immunoglobulin (Ig) and mucin domain (TIM) proteins play critical roles in viral infections. Herein, we report that the TIM-family proteins strongly inhibit HIV-1 release, resulting in diminished viral production and replication. Expression of TIM-1 causes HIV-1 Gag and mature viral particles to accumulate on the plasma membrane. Mutation of the phosphatidylserine (PS) binding sites of TIM-1 abolishes its ability to block HIV-1 release. TIM-1, but to a much lesser extent PS-binding deficient mutants, induces PS flipping onto the cell surface; TIM-1 is also found to be incorporated into HIV-1 virions. Importantly, TIM-1 inhibits HIV-1 replication in CD4-positive Jurkat cells, despite its capability of up-regulating CD4 and promoting HIV-1 entry. In addition to TIM-1, TIM-3 and TIM-4 also block the release of HIV-1, as well as that of murine leukemia virus (MLV) and Ebola virus (EBOV); knockdown of TIM-3 in differentiated monocyte-derived macrophages (MDMs) enhances HIV-1 production. The inhibitory effects of TIM-family proteins on virus release are extended to other PS receptors, such as Axl and RAGE. Overall, our study uncovers a novel ability of TIM-family proteins to block the release of HIV-1 and other viruses by interaction with virion- and cell-associated PS. Our work provides new insights into a virus-cell interaction that is mediated by TIMs and PS receptors.