The expression of anti-protein disulfide isomerase A3 autoantibody is associated with the increased risk of miscarriage in euthyroid women with thyroid autoimmunity

The effects of maternal anti-alpha-enolase antibody expression on the brain development in offspring

Anti-alpha-enolase autoantibodies have not only been found to play an important role in autoimmune diseases but also cause neurological damage in adults. In this study, a pregnant mouse model with high serum alpha-enolase (ENO1)-specific antibody (ENO1Ab) was established by immunization with ENO1 protein to explore the effects of maternal circulatory ENO1Ab on the brain development in offspring. The pups showed impaired learning and memory abilities with obviously thinner tight junctions in the brain tissue. IgG deposits colocalized with both ENO1 protein and complement 3 (C3), and the membrane attack complex was obviously detectable in the brain tissues of pups from dams with high serum ENO1Ab expression. Our findings suggest that highly expressed ENO1Ab in the maternal circulation can pass through the blood-placenta-barrier and the compromised blood-brain barrier into the brain tissues of offspring and may cause neurological development impairment mainly through complement-dependent cytotoxicity.

A Predictive Role of Autoantibodies Against the Epitope aa168–183 of ENO1 in the Occurrence of Miscarriage Related to Thyroid Autoimmunity

Objective

The aim of the research is to study the association between the serum levels of autoantibodies against one important epitope (¹⁶⁸FMILPVGAANFREAMR¹⁸³, designated as P6) of α-enolase (ENO1-P6Abs) and miscarriage among euthyroid females with thyroid autoimmunity (TAI).

Methods

Anti-ENO1-P6 total IgG was investigated in 432 euthyroid women, and its four subclasses were analyzed in 184 euthyroid women. The serum FT4, TSH, TgAb, and TPOAb levels were determined using an electrochemiluminescence immunoassay. The serum ENO1-P6Ab and anti-protein disulfide isomerase A3 autoantibody (PDIA3Ab) levels were determined using an enzyme-linked immunosorbent assay.

Results

The serum levels of anti-ENO1-P6 total IgG, IgG2, IgG3, and IgG4 were significantly higher in euthyroid TAI females than in non-TAI controls. Additionally, anti-ENO1-P6 total IgG and its 4 subtypes were all markedly higher in euthyroid TAI females with pregnancy loss than those without miscarriage. Moreover, logistic regression analysis showed that highly expressed anti-ENO1-P6 total IgG, IgG1, IgG2, and IgG3 subtypes in the serum were all independent risk factors for euthyroid TAI-related miscarriage, and its IgG1 was also for non-TAI-related abortion. According to the trend test, the prevalence of miscarriage was increased in a titer-dependent manner with the raised levels of serum anti-ENO1-P6 total IgG and IgG1, IgG2, and IgG3 subtypes among euthyroid TAI females. The receiver operating characteristic curve analysis of anti-ENO1-P6 total IgG and IgG1, IgG2, and IgG3 subclass expressions in the serum for miscarriage prediction in euthyroid TAI females exhibited that the total areas under the curves were 0.773 ± 0.041, 0.761 ± 0.053, 0.827 ± 0.043, and 0.760 ± 0.050, respectively (all P <0.0001). Their corresponding optimal cut-off OD450 values were 0.68 (total IgG), 0.26 (IgG1), 0.97 (IgG2), and 0.48 (IgG3), with sensitivities of 70.8, 87.5, 83.3, and 85.4%, and specificities of 70.8, 59.1, 77.3, and 56.8%, respectively. There was an additive interaction between serum anti-ENO1-P6 and anti-PDIA3 total IgGs on the development of miscarriage (RERI = 23.6, AP = 0.79, SI = 5.37).

Conclusion

The highly expressed ENO1-P6Abs may be important risk factors for euthyroid TAI-related miscarriage. The serum levels of ENO1-P6Abs may become good predictive markers for pregnancy loss in euthyroid TAI females, especially its IgG2 subclass expression.

Protein Disulfide-Isomerase A3 Is a Robust Prognostic Biomarker for Cancers and Predicts the Immunotherapy Response Effectively

Background

Protein disulfide isomerase A3 (PDIA3) is a member of the protein disulfide isomerase (PDI) family that participates in protein folding through its protein disulfide isomerase function. It has been reported to regulate the progression of several cancers, but its function in cancer immunotherapy is unknown.

Methods

The RNA-seq data of cancer and normal tissues were downloaded from The Cancer Genome Atlas (TCGA) and the Genotype-Tissue Expression (GTEx) databases. The Cbioportal dataset was used to explore the genomic alteration information of PDIA3 in pan-cancer. Human Protein Atlas (HPA) and ComPPI websites were employed to mine the protein information of PDIA3, and western blot assay was performed to monitor the upregulated PDIA3 expression in clinical GBM samples. The univariate Cox regression and the Kaplan–Meier method were utilized to appraise the prognostic role of PDIA3 in pan-cancer. Gene Set Enrichment Analysis (GSEA) was applied to search the associated cancer hallmarks with PDIA3 expression. TIMER2.0 was the main platform to investigate the immune cell infiltrations related to PDIA3 in pan-cancer. The associations between PDIA3 and immunotherapy biomarkers were performed by Spearman correlation analysis. The immunoblot was used to quantify the PDIA3 expression levels, and the proliferative and invasive ability of glioma cells was determined by colony formation and transwell assays.

Findings

PDIA3 is overexpressed in most cancer types and exhibits prognosis predictive ability in various cancers, and it is especially expressed in the malignant cells and monocytes/macrophages. In addition, PDIA3 is significantly correlated with immune-activated hallmarks, cancer immune cell infiltrations, and immunoregulators, and the most interesting finding is that PDIA3 could significantly predict anti-PDL1 therapy response. Besides, specific inhibitors that correlated with PDIA3 expression in different cancer types were also screened by using Connectivity Map (CMap). Finally, knockdown of PDIA3 significantly weakened the proliferative and invasive ability of glioma cells.

Interpretation

The results revealed that PDIA3 acts as a robust tumor biomarker. Its function in protein disulfide linkage regulation could influence protein synthesis, degradation, and secretion, and then shapes the tumor microenvironment, which might be further applied to develop novel anticancer inhibitors.