Immune Checkpoint-Related Gene Polymorphisms Are Associated With Primary Immune Thrombocytopenia

Impact of the Multiple Sclerosis-Associated Genetic Variant CD226 Gly307Ser on Human CD8 T-Cell Functions

BACKGROUND AND OBJECTIVES

The rs763361 nonsynonymous variant in the CD226 gene, which results in a glycine-to-serine substitution at position 307 of the CD226 protein, has been implicated as a risk factor of various immune-mediated diseases, including multiple sclerosis (MS). Compelling evidence suggests that this allele may play a significant role in predisposing individuals to MS by decreasing the immune-regulatory capacity of Treg cells and increasing the proinflammatory potential of effector CD4 T cells. However, the impact of this CD226 gene variant on CD8 T-cell functions, a population that also plays a key role in MS, remains to be determined.

METHODS

To study whether the CD226 risk variant affects human CD8 T-cell functions, we used CD8 T cells isolated from peripheral blood mononuclear cell of 16 age-matched healthy donors homozygous for either the protective or the risk allele of CD226. We characterized these CD8 T cells on T-cell receptor (TCR) stimulation using high-parametric flow cytometry and bulk RNAseq and through characterization of canonical signaling pathways and cytokine production.

RESULTS

On TCR engagement, the phenotype of ex vivo CD8 T cells bearing the protective (CD226-307Gly) or the risk (CD226-307Ser) allele of CD226 was largely overlapping. However, the transcriptomic signature of CD8 T cells from the donors carrying the risk allele presented an enrichment in TCR, JAK/STAT, and IFNγ signaling. We next found that the CD226-307Ser risk allele leads to a selective increase in the phosphorylation of the mitogen-activated protein kinases extracellular signal-regulated kinases 1 and 2 (ERK1/2) associated with enhanced phosphorylation of STAT4 and increased production of IFNγ.

DISCUSSION

Our data suggest that the CD226-307Ser risk variant imposes immune dysregulation by increasing the pathways related to IFNγ signaling in CD8 T cells, thereby contributing to the risk of developing chronic inflammation.

Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) gene polymorphisms in a cohort of Egyptian patients with immune thrombocytopenia (ITP)

BACKGROUND

Immune thrombocytopenia (ITP) is characterized by immune response dysregulations. Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) plays a central role in immune checkpoint pathways and preventing autoimmune diseases by regulating immune tolerance. We aimed to explore the potential association between CTLA-4 gene polymorphisms and ITP as well as study their impact on the response to therapy.

METHODS

We investigated two CTLA-4 single-nucleotide polymorphisms (SNPs; rs: 231775 and rs: 3087243) using real-time PCR as well as the plasma levels of CTLA-4 by ELISA in 88 patients with ITP and 44 healthy participants (HC).

RESULTS

CTLA-4 (rs: 3087243) A > G polymorphism analysis showed most HC had the homozygous AA genotype, which was statistically significant compared to patients with ITP. Plasma levels of CTLA4 were statistically lower in patients with acute ITP. There was no correlation between CTLA-4 (rs: 231775 and rs: 3087243) A/G SNPs were not correlated to the response to all lines of therapy assessed (corticosteroids, thrombopoietin receptor agonists, splenectomy, and rituximab).

CONCLUSION

CTLA-4 CT 60 A/G may affect the susceptibility of ITP, but both CTLA-4 + 49 A/G and CT60 A/G did not impact the response of patients with ITP to different lines of therapy.

The role of T cells and myeloid-derived suppressor cells in refractory immune thrombocytopenia

Immune thrombocytopenia (ITP) is characterized by a dysregulated immune response against platelets, affecting both their destruction and production. A role for an abnormal T-cell compartment has been established in ITP pathogenesis and treatments that increase platelet counts in patients with ITP have shown improvements in T-cell profiles. On the other hand, patients who were refractory to treatment appear to retain the T-cell abnormalities as before. Myeloid-derived suppressive cells (MDSCs) are also emerging as key contributors to the immune pathology of ITP and response to treatment. In this review, we will discuss how various treatments affect the T-cell and MDSC compartments in ITP. The review will focus on studies that have examined the underlying mechanisms and/or genetic basis responsible for refractoriness to a given treatment and highlight remaining challenges in identifying factors and mechanisms to predict response to treatment.

Immune checkpoint-related gene polymorphisms are associated with acute myeloid leukemia

BACKGROUND

Chemotherapy is still the standard regimen for treating acute myeloid leukemia (AML) and its disappointing efficacy requires the urgent need for new therapeutic targets. It is well known that immune response plays an increasingly significant role in the pathogenesis of AML.

METHODS

We detected nine single nucleotide polymorphisms (SNPs) in immune checkpoint-related genes, including PD1, LAG3, TIM3, and TIGIT in 285 AML inpatients and 324 healthy controls. SNP genotyping was performed on the MassARRAY platform. Furthermore, we analyzed the relationship between the susceptibility and prognosis of AML and the selected SNPs.

RESULTS

Our results showed that rs2227982 and rs10204525 in PD1 were significantly associated with susceptibility to AML after false discovery rate correction. PD1 rs10204525 also showed a significant correlation with the response to chemotherapy and risk stratification of AML. Importantly, the AA genotype of PD1 (rs2227982) under the recessive model showed a negative impact on AML prognosis independently.

CONCLUSIONS

Our results indicate that PD1 SNPs are important for susceptibility and prognosis in AML, which may provide a new therapeutic target for AML patients.

Single Nucleotide Polymorphisms Associated with Rheumatoid Arthritis in Saudi Patients

Rheumatoid arthritis (RA) is a complex, multifactorial disorder with an autoimmune etiology. RA is highly heritable and is associated with both human leucocyte antigen (HLA) and non-HLA genes. We investigated the associations of 33 single nucleotide polymorphisms (SNPs) with RA in the Saudi population.

METHODS

This study included 105 patients with RA and an equal number of age- and sex-matched controls. The patients with RA attended outpatient clinics at King Khalid University Hospital in Riyadh, Saudi Arabia. Blood samples were collected, and DNA was extracted using Qiagen kits. Primers were designed for the 33 selected SNPs using the MassEXTEND primers program, and samples were genotyped on the Sequenom MassARRAY iPLEX platform. The allele frequencies and genotypes were determined for each SNP, and the results obtained for the patients were compared to those for the controls.

RESULTS

The allele and genotype frequencies of six SNPs were significantly associated with RA: rs1188934, rs10919563, rs3087243, rs1980422, rs10499194, and rs629326. The minor alleles of rs1188934, rs10919563, rs10499194, and rs629326 were protective, with odds ratios of 0.542, 0.597, 0.589, and 0.625, and p-values of 0.002, 0.023, 0.013 and 0.036, respectively. In addition, the heterozygote frequencies of two SNPs (rs6859219 and rs11586238) were significantly higher in the controls than in the patients.

CONCLUSIONS

There is considerable heterogeneity in the genetics of RA in different populations, and the SNPs that are associated with RA in some populations are not in others. We studied 33 SNPs and only eight were associated with RA. The remaining SNPs showed no allelic or genotypic associations with RA.

Evaluation of the possible association of PDCD-1 and LAG3 gene polymorphisms with hepatocellular carcinoma risk

PURPOSE

Programmed death-1 (PDCD-1) and lymphocyte activating 3 (LAG3), two important immunosuppressive molecules, play crucial roles in immune escape of tumor cells. This study evaluated the effects of PDCD-1 (rs10204525 and rs36084323), and LAG3 (rs870849 and rs1882545) gene polymorphisms on hepatocellular carcinoma (HCC) risk.

METHODS

341 patients with HCC and 350 cancer-free controls in the South Chinese population were included in a population-based case-control study. DNAs were extracted from peripheral blood samples. Genotypes were analyzed using multiplex PCR and sequencing. SNPs were analyzed using multiple inheritance models (co-dominant, dominant, recessive, and over-dominant).

RESULTS

The allele and genotype frequencies of neither of the four polymorphisms, adjusted for age and gender, differed between HCC patients and controls. The differences were also not significant after stratifying by gender and age. According to our results, HCC patients with rs10204525 TC genotype had significantly lower AFP levels than HCC patients with rs10204525 TT genotype (P = 0.004). Moreover, the frequency of PDCD-1 rs36084323 CT genotype reduced the risk of TNM grade (CT vs. C/C-T/T: OR = 0.57, 95%CI = 0.37-0.87, P = 0.049).

CONCLUSION

Our results demonstrated that the PDCD-1 (rs10204525 and rs36084323), and LAG3 (rs870849 and rs1882545) polymorphism did not influence the risk of HCC, PDCD-1 rs10204525 TC genotype was associated with the lower AFP levels and rs36084323 CT genotypes were related to HCC tumor grades in the South Chinese samples.

Nectin Family Ligands Trigger Immune Effector Functions in Health and Autoimmunity

The superfamily of immunoglobulin cell-adhesion molecules (IgCAMs) is a well-known family of cell-adhesion molecules used for immune-cell extravasation and cell-cell interaction. Amongst others, this family includes DNAX accessory molecule 1 (DNAM-1/CD226), class-I-restricted T-cell-associated molecule (CRTAM/CD355), T-cell-activated increased late expression (Tactile/CD96), T-cell immunoreceptor with Ig and ITIM domains (TIGIT), Nectins and Nectin-like molecules (Necls). Besides using these molecules to migrate towards inflammatory sites, their interactions within the immune system can support the immunological synapse with antigen-presenting cells or target cells for cytotoxicity, and trigger diverse effector functions. Although their role is generally described in oncoimmunity, this review emphasizes recent advances in the (dys)function of Nectin-family ligands in health, chronic inflammatory conditions and autoimmune diseases. In addition, this review provides a detailed overview on the expression pattern of Nectins and Necls and their ligands on different immune-cell types by focusing on human cell systems.

Plasma long noncoding RNAs lncDC and THRIL as potential diagnostic markers of adult primary immune thrombocytopenia

INTRODUCTION

Immune thrombocytopenia (ITP) is a common acquired hemorrhagic disease without "gold standard" for the diagnosis, long non-coding RNA (lncRNAs) can participate in regulating gene expression through various mechanisms and may play a role in immune intolerance in ITP. Several previous studies have confirmed that lncRNA lncDC and THRIL are involved in the development of autoimmune diseases. This study investigates the relationship between expression levels of two plasma lncRNAs (lncDC and THRIL) and clinical characteristics of adult primary ITP patients, ascertain their potential applications as diagnostic markers of ITP.

METHODS

We recruited 102 subjects, including 41 ITP patients, 41 healthy controls (HCs) and 20 patients under myelosuppression phase after chemotherapy (MS). qRT-PCR was used to detect the expression of two lncRNAs in the peripheral blood plasma of the three groups. Receiver operating characteristic (ROC) curves were used to test the diagnostic efficacy of lncDC and THRIL in ITP.

RESULTS

The expression level of lncDC was downregulated in ITP patients compared with HCs (p = . 012) and MS (p = .035), whereas THRIL was significantly upregulated (p = .0005, p < . 0001). We further revealed that lncDC has a high sensitivity (78. 05%), while THRIL has a high specificity (97. 56%). The area under the curve (AUC) (0.869, 95% CI: 0.795-0.943, p < .0001) of the ROC curve for this combination increased significantly.

CONCLUSIONS

THRIL and lncDC expression levels were changed in adult ITP patients. The lncRNAs lncDC and THRIL can serve as potential diagnostic markers for adult primary ITP.

Scoping Review on Epigenetic Mechanisms in Primary Immune Thrombocytopenia

Immune Thrombocytopenia (ITP) is an autoimmune blood disorder that involves multiple pathways responsible for the homeostasis of the immune system. Numerous pieces of literature have proposed the potential of immune-related genes as diagnostic and prognostic biomarkers, which mostly implicate the role of B cells and T cells in the pathogenesis of ITP. However, a more in-depth understanding is required of how these immune-related genes are regulated. Thus, this scoping review aims to collate evidence and further elucidate each possible epigenetics mechanism in the regulation of immunological pathways pertinent to the pathogenesis of ITP. This encompasses DNA methylation, histone modification, and non-coding RNA. A total of 41 studies were scrutinized to further clarify how each of the epigenetics mechanisms is related to the pathogenesis of ITP. Identifying epigenetics mechanisms will provide a new paradigm that may assist in the diagnosis and treatment of immune thrombocytopenia.

Lack of Association between Common LAG3/CD4 Variants and Risk of Migraine

Several papers have been published suggesting a probable role of inflammatory factors in the etiopathogenesis of migraine. In this study, we investigated the possible association between common variants in the LAG3/CD4 genes (both genes, which are closely related, encode proteins involved in inflammatory and autoimmune responses) in the risk of migraine in a cohort of Caucasian Spanish participants. For this purpose, the frequencies of CD4 rs1922452, CD4 rs951818, and LAG3 rs870849 genotypes and allelic variants, using a specific TaqMan-based qPCR assay, were assessed in 290 patients diagnosed with migraine and in 300 healthy controls. The relationship of these variables with several clinical features of migraine was also analyzed. The frequencies of the analyzed LAG3/CD4 genotypes did not differ significantly between the two study groups and were not related to the sex, age at onset of migraine, family history of migraine, presence or absence of aura, or the triggering effect of ethanol on migraine episodes. These results suggest a lack of association between common variants in the LAG3/CD4 genes and the risk of developing migraine in the Caucasian Spanish population.

Association between LAG3/CD4 Genes Variants and Risk for Multiple Sclerosis

Several recent works have raised the possibility of the contribution of the lymphocyte activation gene 3 (LAG3) protein in the inflammatory processes of multiple sclerosis (MS). Results of studies on the possible association between LAG3 gene variants and the risk of MS have been inconclusive. In this study, we tried to show the possible association between the most common single nucleotide variants (SNVs) in the CD4 and LAG3 genes (these two genes are closely related) and the risk of MS in the Caucasian Spanish population. We studied the genotypes and allelic variants CD4 rs1922452, CD4 rs951818, and LAG3 rs870849 in 300 patients diagnosed with MS and 400 healthy patients using specific TaqMan-based qPCR assays. We analyzed the possible influence of the genotype frequency on age at the onset of MS, the severity of MS, clinical evolutive subtypes of MS, and the HLADRB1*1501 genotype. The frequencies of the CD4 rs1922452, CD4 rs951818, and LAG3 rs870849 genotypes and allelic variants were not associated with the risk of MS and were unrelated to gender, age at onset and severity of MS, the clinical subtype of MS, and HLADRB1*1501 genotype. The results of the current study showed a lack of association between the CD4 rs1922452, CD4 rs951818, and LAG3 rs870849 SNVs and the risk of developing MS in the Caucasian Spanish population.

LAG3/CD4 Genes Variants and the Risk for Restless Legs Syndrome

According to several studies, inflammatory factors could be related to the pathogenesis of idiopathic restless legs syndrome (RLS). In addition, RLS and Parkinson's disease (PD) have shown a possible relationship, and recent studies have shown an association between CD4 rs1922452 and CD4 rs951818 single nucleotide variants (SNVs) and the risk for PD. For these reasons, we investigated the possible association between common variants in the LAG3/CD4 genes (which encoded proteins involved in inflammatory and autoimmune responses) and the risk for RLS in a Caucasian Spanish population. We assessed the frequencies of CD4 rs1922452, CD4 rs951818, and LAG3 rs870849 genotypes and allelic variants in 285 patients with idiopathic RLS and 350 healthy controls using a specific TaqMan-based qPCR assay. We also analyzed the possible influence of the genotypes' frequencies on several variables, including age at onset of RLS, gender, family history of RLS, and response to drugs commonly used in the treatment of RLS. We found a lack of association between the frequencies of genotypes and allelic variants of the 3 SNVs studied and the risk of RLS, and a weak though significant association between the CD4 rs1922452 GG genotype and an older age at onset of RLS. With the exception of this association, our findings suggest that common SNVs in the CD4/LAG3 genes are not associated with the risk of developing idiopathic RLS in Caucasian Spanish people.

Comprehensive analysis of the relationship between cuproptosis-related genes and esophageal cancer prognosis

BACKGROUND

Esophageal cancer is one of the most common malignant tumors of the digestive system, with a 5-year survival rate of 15% to 50%. Cuproptosis, a unique kind of cell death driven by protein lipoylation, is strongly connected to mitochondrial metabolism. The clinical implications of cuproptosis-related genes in esophageal cancer, however, are mainly unknown.

AIM

To identify cuprotosis-related genes that are differentially expressed in esophageal cancer and investigate their prognostic significance.

METHODS

With |log fold change| > 1 and false discovery rate < 0.05 as criteria, the Wilcox test was used to evaluate the differentially expressed genes between 151 tumor tissues and 151 normal esophageal tissues. Cuproptosis-related genes were selected to be linked with prognosis using univariate Cox regression analysis. Genes were separated into high- and low- expression groups based on their cutoff value of gene expression, and the correlation between the two groups and overall survival or progression-free survival was investigated using the log-rank test. The C-index, calibration curve, and receiver operator characteristic (ROC) curve were used to assess a nomogram containing clinicopathological characteristics and cuproptosis-related genes.

RESULTS

Pyruvate dehydrogenase A1 (PDHA1) was found to be highly correlated with prognosis in univariate Cox regression analysis (hazard ratio = 22.96, 95% confidence interval = 3.09-170.73; P = 0.002). According to Kaplan-Meier survival curves, low expression of PDHA1 was associated with a better prognosis (log-rank P = 0.0007). There was no significant correlation between PDHA1 expression and 22 different types of immune cells. Tumor necrosis factor superfamily member 15 (TNFSF15) (P = 3.2 × 10^-6; r = 0.37), TNFRSF14 (P = 8.1 × 10^-8; r = 0.42), H long terminal repeat-associating 2 (P = 6.0 × 10^-8; r = 0.42) and galectin 9 (P = 3.1 × 10^-6; r = 0.37) were all found to be considerably greater in the high PDHA1 expression group, according to an analysis of genes related to 47 immunological checkpoints. The low PDHA1 expression group had significantly lower levels of cluster of differentiation 44 (CD44) (P = 0.00028; R = -0.29), TNFRSF18 (P = 1.2 × 10^-5; R = -0.35), programmed cell death 1 ligand 2 (P = 0.0032; R = -0.24), CD86 (P = 0.018; R = -0.19), and CD40 (P = 0.0047; R = -0.23), and the differences were statistically significant. We constructed a prognostic nomogram incorporating pathological type, tumor-node-metastasis stage, and PDHA1 expression, and the C-index, calibration curve, and ROC curve revealed that the nomogram’s predictive performance was good.

CONCLUSION

Cuproptosis-related genes can be used as a prognostic predictor for esophageal cancer patients, providing novel insights into cancer treatment.

G307S DNAM-1 Mutation Exacerbates Autoimmune Encephalomyelitis via Enhancing CD4+ T Cell Activation

Although rs763361, which causes a nonsynonymous glycine-to-serine mutation at residue 307 (G307S mutation) of the DNAX accessory molecule-1 (DNAM-1) immunoreceptor, is a single-nucleotide polymorphism associated with autoimmune disease susceptibility, little is known about how the single-nucleotide polymorphism is involved in pathogenesis. In this study, we established human CD4+ T cell transfectants stably expressing wild-type (WT) or G307S DNAM-1 and showed that the costimulatory signal from G307S DNAM-1 induced greater proinflammatory cytokine production and cell proliferation than that from wild-type DNAM-1. The G307S mutation also enhanced the recruitment of the tyrosine kinase Lck and augmented p-Tyr322 of DNAM-1. We also established a mouse myelin Ag-specific CD4+ T cell transfectant stably expressing the chimeric DNAM-1 (chDNAM-1) consisting of the extracellular, transmembrane, and a part of intracellular regions of mouse DNAM-1 (residues 1-285) fused with the part of the intracellular region (residues 286-336) of human WT or G307S chDNAM-1. Adoptive transfer of the mouse T cell transfectant expressing the G307S chDNAM-1 into mice exacerbated experimental autoimmune encephalomyelitis compared with the transfer of cells expressing the WT chDNAM-1. These findings suggest that rs763361 is a gain-of-function mutation that enhances DNAM-1-mediated costimulatory signaling for proinflammatory responses.

Association between LAG3/CD4 gene variants and risk of Parkinson's disease

BACKGROUND/OBJECTIVES

Several recent studies suggest a possible role of lymphocyte activation 3 (LAG3) protein. LAG3 can behave as an α-synuclein ligand, and serum and cerebrospinal fluid-soluble LAG3 levels have been proposed as a marker of Parkinson's disease (PD). In this study, we aimed to investigate whether there is an association between 3 common single-nucleotide variations (SNVs) in the LAG3 gene and its closely related CD4 molecule gene and the risk of PD in a Caucasian Spanish population. Two of them have been previously associated with the risk of PD in Chinese females.

METHODS

We analysed genotypes and allele frequencies for CD4 rs1922452, CD4 951818 and LAG3 rs870849 SNVs, by using specifically designed TaqMan assays, in a cohort composed of 629 PD patients and 865 age- and gender-matched healthy controls.

RESULTS

The frequencies of the CD4 rs1922452 A/A genotype, according to the dominant and recessive genetic models, and of the CD4 rs1922452/A allelic variant were significantly lower, and the frequencies of the CD4 rs951818 A/A genotype, according to the dominant genetic model, and of the CD4 rs951818/A allele, were significantly higher in PD patients than in controls. The differences were not significant after stratifying by sex. These two SNVs showed strong linkage. Regression models showed a lack of relation between the 3 SNVs studied and the age at onset of PD.

CONCLUSIONS

These data suggest a possible role of CD4 rs1922452 and CD4 rs951818 polymorphisms in the risk of PD.

Single Nucleotide Polymorphisms of the HIF1A Gene are Associated With Sensitivity of Glucocorticoid Treatment in Pediatric ITP Patients

BACKGROUND

Hypoxia-inducible factor-1α (HIF-1α) plays a crucial role in both innate and adaptive immunity. Emerging evidence indicates that HIF-1α is associated with the inflammation and pathologic activities of autoimmune diseases, suggesting that HIF1α may be involved in immune dysregulation in patients with immune thrombocytopenia (ITP). The purpose of this study was to evaluate whether single nucleotide polymorphisms (SNPs) of the HIF1A gene are associated with susceptibility to ITP and its clinical prognosis including incidence of chronic ITP and glucocorticoid sensitivity.

MATERIALS AND METHODS

This study involved 197 Chinese ITP pediatric patients (discovery cohort) and 220 healthy controls. The Sequenom MassArray system (Sequenom, San Diego, CA) was used to detect 3 SNPs genotypes in the HIF1A gene: rs11549465, rs1957757, and rs2057482. We also used another ITP cohort (N=127) to validate the significant results of SNPs found in the discovery cohort.

RESULTS

The frequencies of the three SNPs did not show any significant differences between the ITP and healthy control groups. The CT genotype at rs11549465 was significantly higher in ITP patients sensitive to glucocorticoid treatment than in those insensitive to glucocorticoid treatment (P=0.025). These results were validated using another ITP cohort (N=127, P=0.033). Moreover, the CC genotype was a risk factor for insensitive to GT the odds ratio (95% confidence interval) was 5.96 (5.23-6.69) in standard prednisone (P=0.0069) and 6.35 (5.33-7.37) in high-dose dexamethasone (P=0.04).

CONCLUSIONS

Although HIF1A gene polymorphisms were not associated with susceptibility to ITP, the CT genotype at rs11549465 was associated with the sensitivity to glucocorticoid treatment of ITP patients, suggesting that the rs11549465 SNP may contribute to the sensitivity of glucocorticoid treatment in pediatric ITP patients.

Investigation of the correlation between immune thrombocytopenia and T cell activity-regulated gene polymorphism using functional study

Thrombocytopenia is a condition where the platelet count is under 100 × 10⁹/L, which is caused by various disorders. However, the mechanism of thrombocytopenia is still unclear. Hence, we tried to investigate the correlation between immune thrombocytopenia (ITP) and single nucleotide polymorphisms (SNPs) of genes related to T cell activation. There were 32 ITP patients and 30 healthy controls enrolled in this study. PCR and sequencing were used to find out the significant SNPs, which we focused on the promoter region of CTLA4 and CD28. In this study, the ITP cases were divided into primary ITP group, secondary ITP group, and the combination of the two to the follow-up analysis. Moreover, dual-luciferase reporter assay was used to evaluate the transcription activity of the significant SNP. We found the − 1765_rs11571315 of CTLA4 gene was associated with primary ITP (p = 0.006), secondary ITP (p = 0.008), and the combination of the two (p = 0.003). Moreover, the −318_rs5742909 also had statistical significance in secondary ITP group that was only caused by autoimmune disease (p = 0.019). In functional study, the rs5742909 would decrease 19% of the transcription activity when it carried a T-allele at this position (p = 0.040). It was noted that CTLA4 gene polymorphism was related to ITP but not CD28. According to our results, we surmised that CTLA4 is involved in the pathogenesis of ITP, and the secondary ITP result from the lower CTLA4 expression that leads to T cell over-activation.

Intravenous Immunoglobulin Therapy Restores the Quantity and Phenotype of Circulating Dendritic Cells and CD4+ T Cells in Children With Acute Kawasaki Disease

Background

Intravenous immunoglobulin (IVIG) showed its therapeutic efficacy on Kawasaki disease (KD). However, the mechanisms by which it reduces systemic inflammation are not completely understood. Dendritic cells (DCs) and T cells play critical roles in the pathogenic processes of immune disorders. Assessing the quantity of DC subsets and T cells and identifying functional molecules present on these cells, which provide information about KD, in the peripheral blood may provide new insights into the mechanisms of immunoglobulin therapy.

Methods

In total, 54 patients with KD and 27 age-matched healthy controls (HCs) were included in this study. The number, percentage, and phenotype of DC subsets and CD4⁺ T cells in peripheral blood were analyzed through flow cytometry.

Results

Patients with KD exhibited fewer peripheral DC subsets and CD4⁺ T cells than HCs. Human leucocyte antigen-DR (HLA-DR) expression was reduced on CD1c⁺ myeloid DCs (CD1c⁺ mDCs), whereas that on plasmacytoid DCs (pDCs) did not change significantly. Both pDCs and CD1c⁺ mDCs displayed significantly reduced expression of co-stimulatory molecules, including CD40, CD86. pDCs and CD1c⁺ mDCs presented an immature or tolerant phenotype in acute stages of KD. Number of circulating pDC and CD1c⁺ mDC significantly inversely correlated with plasma interleukin-6 (IL-6) levels in KD patients pre-IVIG treatment. No significant differences were found concerning the DC subsets and CD4⁺ T cells in patients with KD with and without coronary artery lesions. Importantly, these altered quantity and phenotypes on DC subsets and CD4⁺ T cells were restored to a great extent post-IVIG treatment. T helper (Th) subsets including Th1 and Th2 among CD4⁺ T cells did not show alteration pre- and post-IVIG treatment, although the Th1-related cytokine IFN-γ level in plasma increased dramatically in patients with KD pre-IVIG treatment.

Conclusions

pDCs and CD1c⁺ mDCs presented an immature or tolerant phenotype in acute stages of KD, IVIG treatment restored the quantity and functional molecules of DCs and CD4⁺ T cells to distinct levels in vivo, indicating the involvement of DCs and CD4⁺ T cells in the inflammation in KD. The findings provide insights into the immunomodulatory actions of IVIG in KD.

Lymphocyte Activation Gene 3 Single-Nucleotide Polymorphisms in Bone Marrow Failure Diseases

Introduction. Lymphocyte activation gene 3 (LAG3) is an inhibitory checkpoint protein expressed on activated T effector, T regulatory, and natural killer cells. The main function of LAG3 is the regulation of immune homeostasis. Several studies have suggested its role in malignant and autoimmune diseases. The objective of this study was to explore the association between LAG3 single-nucleotide polymorphisms (SNPs) and bone marrow failure diseases. Methods. Sixty-two patients newly diagnosed with bone marrow failure diseases in the Hematology Department of Tianjin Medical University General Hospital between January 2019 and December 2020 and 16 healthy controls were enrolled in this study. SNPs in LAG3 were investigated by performing Sanger sequencing, and the association of the detected SNPs with bone marrow failure diseases was analyzed. Results. Eleven SNPs were identified. Among them, the frequency of LAG3 rs1941928301 (C>T) was statistically different among the groups ( $P=0.013$ ). It was higher in the myelodysplastic syndrome (MDS) group than that in the severe aplastic anemia (SAA) group ( $P=0.004$ ) and that in the healthy control group ( $P=0.009$ ). Conclusions. LAG3 rs1941928301 (C>T) might be associated with a higher risk of MDS. The detected LAG3 SNPs have no apparent effect on susceptibility to SAA and immune-related pancytopenia (IRP).

A risk model based on autophagy-related lncRNAs for predicting prognosis and efficacy of immunotherapy and chemotherapy in gastric cancer patients

Long non-coding RNAs (lncRNAs) are a class of non-protein-coding RNAs essential to the occurrence and development of gastric cancer (GC). We aimed to identify critical lncRNA pairs to construct a prognostic model and assess its performances in prognosis and efficacy prediction in GC patients receiving immunotherapy and chemotherapy. We searched transcriptome and clinical data of GC patients from The Cancer Genome Atlas (TCGA) database. Autophagy-related lncRNAs were identified using co-expression network analysis, and lncRNA pairs with prognostic value were selected using pairwise transcriptome analysis. The gene pairs were subjected to LASSO algorithm for identification of optimal gene pairs for risk model construction. Patients were classified into the low-risk and high-risk groups with the RiskScore as a cutoff. Finally, 9 optimal gene pairs were identified in the LASSO algorithm model for construction of a lncRNA prognostic risk model. For predictive performances, it successfully predicted a shorter survival of high-risk patients than that obtained in low-risk individuals (P < 0.001). It showed moderate AUC (area under the curve) values for 1-, 2-, and 3-year overall survival prediction of 0.713 and could serve as an independent predictor for GC prognosis. Compared to the low-risk group, high-risk patients had higher expressions of marker genes for immune checkpoint inhibitors (ICIs) and showed higher sensitivity to the chemotherapy agents, rapamycin, bexarotene, and bicalutamide. Our findings demonstrate a robust prognostic model based on nine autophagy-related lncRNA pairs for GC. It acts as an independent predictor for survival and efficacy prediction of immunotherapy and chemotherapy in GC patients.