Elevated semaphorin5A in systemic lupus erythematosus is in association with disease activity and lupus nephritis

Ankrd1 as a potential biomarker for the transition from acute kidney injury to chronic kidney disease

Ischemia-reperfusion injury (IRI) is one of the leading causes of acute kidney injury (AKI), predisposing patients to chronic kidney disease (CKD) due to maladaptive renal repair. Nevertheless, the molecular mechanisms and biomarkers that cause maladaptive repair remain unclear. In this study, we used single-nucleus RNA sequencing data from GEO database (GSE139107) to identify molecular markers during the transition from AKI to CKD caused by IRI. Analysis of intercellular crosstalk, trajectory and machine learning algorithms revealed hub cell clusters and genes. Proximal tubule (PT) cells, especially a new cluster (New PT2), significantly interacted with fibroblasts during the transition. The expression levels of hub genes were validated using the bulk RNA-seq data (GSE98622) and further confirmed through RT-qPCR and immunohistochemical analysis in ischemia-reperfusion injury (uIRI) mice. Ankrd1, a hub gene in New PT2, showed sustained upregulation in the proximal tubule in AKI. Compared to the sham-operated group, the expression of Ankrd1 in mice increased at 0.5 days post-reperfusion, peaked at day 1, and remained significantly elevated up to 60 days. This study indicated that the upregulation of Ankrd1 was positively associated with the progression from AKI to CKD and may potentially serve as a valuable biomarker for this transitional process.

Analysis of expression and its clinical significance of the ADAMTS-2 in systemic lupus erythematosus

OBJECTIVES

ADAMTS-2 is a procollagen N-proteinase that plays an important role in inflammation regulation. The objective of our research is to explore the expression of ADAMTS-2 in Systemic Lupus Erythematosus (SLE), and analyze its relationship with clinical features of SLE, and evaluate the potential value of ADAMTS-2 as a diagnostic biomarker in SLE.

METHODS

ADAMTS-2 expression in PBMCs was detected by RT-qPCR in SLE patients, RA patients, and healthy controls (HC). The diagnostic value of ADAMTS-2 for SLE was evaluated by ROC curve, and the correlation between ADAMTS-2 and the clinical characteristics of SLE was analyzed by Spearman's rank correlation coefficient. The expression profiles of GSE8650 and GSE82221 were downloaded from the GEO database. We performed GSEA to further understand the functions of ADAMTS-2 in SLE. CIBERSORT was utilized for immune cell infiltration analysis.

RESULTS

RT-qPCR results validated that the expression of ADAMTS-2 in PBMCs was significantly increased in SLE patients than RA patients and HC. ROC anaylsis suggested that ADAMTS-2 has significant value in distinguishing new-onset SLE patients from RA patients and HC (AUC = 0.805, p < 0.0001). The expression of ADAMTS-2 was negatively correlated with C3, WBC, PLT, neutrophil, and monocyte level. PBMCs samples with high ADAMTS-2 expression were enriched in TNFA_SIGNALING_VIA_NFKB pathway. We found that ADAMTS-2 was positively correlated with neutrophils, M0 macrophages and M2 macrophages.

CONCLUSION

ADAMTS-2 may be a potential biomarker of SLE patients and closely related to the occurrence and development of SLE. ADAMTS-2 is expected to be a new target for SLE treatment. Key Points • ADAMTS-2 is a potential biomarker of disease activity in SLE patients that develop a flare. • Samples with high ADAMTS-2 expression are enriched in TNFA_SIGNALING_VIA_NFKB pathway in SLE. • ADAMTS-2 expression is positively correlated with neutrophils, M0 macrophages and M2 macrophages.

Semaphorin 5A promotes Th17 differentiation via PI3K-Akt-mTOR in systemic lupus erythematosus

BACKGROUND

Previously, we reported that serum Semaphorin 5 A (Sema5A) levels were increased in systemic lupus erythematosus (SLE) patients compared with healthy controls (HC), and elevated Sema5A correlated with disease activity and lupus nephritis in SLE patients. In this study, we aimed to further understand the role of Sema5A in promoting Th17 cells differentiation in SLE.

METHODS

Sema5A, interferon gamma (IFN-γ), interleukin 4 (IL-4), interleukin 17 A (IL-17 A) and interleukin 10 (IL-10) were measured by Enzyme Linked Immunosorbent Assay (ELISA). RNA and protein were isolated from peripheral blood mononuclear cells (PBMCs) in SLE patients and HC. Expression of PlexinA1 and PlexinB3 were measured by quantitative RT-PCR (qRT-PCR) and Western Blot. Th cell subsets were detected by flow cytometry. Treatment with recombinant human Sema5A (rhSema5A) and small interfering RNA (siRNA) were employed to examine the in vitro effect of Sema5A in CD4+T cell differentiation in SLE patients.

RESULTS

IL-17 A elevated in SLE patients and positively correlated with Sema5A. PlexinA1 was upregulated and mainly expressed in CD4+ T cells of SLE; Sema5A treatment induced the differentiation of Th17 cells, while did not affect the Th1 and Th2 skewing. These effects were associated with an upregulation of the transcription factor RORγt by Th17 cells, but not T-bet or GATA3 in Th1 and Th2 cells, respectively. Knock down PlexinA1 regulates IL-17 A production by CD4+T cells. Functional assays showed that Sema5A-PlexinA1 axis promoted Th17 cells differentiation via PI3K/Akt/mTOR signaling.

CONCLUSIONS

These findings demonstrated that Sema5A-PlexinA1 axis acts as a key mediator on Th17 differentiation, suggesting that Sema5A might be a novel therapeutic target in SLE.

Associations of SEMA7A, SEMA4D, ADAMTS10, and ADAM8 with KRAS, NRAS, BRAF, PIK3CA, and AKT Gene Mutations, Microsatellite Instability Status, and Cytokine Expression in Colorectal Cancer Tissue

Semaphorins (SEMAs), ADAM, and ADAMTS family members are implicated in various cancer progression events within the tumor microenvironment across different cancers. In this study, we aimed to evaluate the expression of SEMA7A, SEMA4D, ADAM8, and ADAMTS10 in colorectal cancer (CRC) in relation to the mutational landscape of KRAS, NRAS, BRAF, PIK3CA, and AKT genes, microsatellite instability (MSI) status, and clinicopathological features. We also examined the associations between the expression of these proteins and selected cytokines, chemokines, and growth factors, assessed using a multiplex assay. Protein concentrations were quantified using ELISA in CRC tumors and tumor-free surgical margin tissue homogenates. Gene mutations were evaluated via RT-PCR, and MSI status was determined using immunohistochemistry (IHC). GSEA and statistical analyses were performed using R Studio. We observed a significantly elevated expression of SEMA7A in BRAF-mutant CRC tumors and an overexpression of ADAM8 in KRAS 12/13-mutant tumors. The expression of ADAMTS10 was decreased in PIK3CA-mutant CRC tumors. No significant differences in the expression of the examined proteins were observed based on MSI status. The SEMA7A and SEMA4D expressions were correlated with the expression of numerous cytokines associated with various immune processes. The potential immunomodulatory functions of these molecules and their suitability as therapeutic targets require further investigation.

Biomarkers associated with immune-related adverse events induced by immune checkpoint inhibitors

Immune checkpoint inhibitors (ICIs) constitute a pivotal class of immunotherapeutic drugs in cancer treatment. However, their widespread clinical application has led to a notable surge in immune-related adverse events (irAEs), significantly affecting the efficacy and survival rates of patients undergoing ICI therapy. While conventional hematological and imaging tests are adept at detecting organ-specific toxicities, distinguishing adverse reactions from those induced by viruses, bacteria, or immune diseases remains a formidable challenge. Consequently, there exists an urgent imperative for reliable biomarkers capable of accurately predicting or diagnosing irAEs. Thus, a thorough review of existing studies on irAEs biomarkers is indispensable. Our review commences by providing a succinct overview of major irAEs, followed by a comprehensive summary of irAEs biomarkers across various dimensions. Furthermore, we delve into innovative methodologies such as machine learning, single-cell RNA sequencing, multiomics analysis, and gut microbiota profiling to identify novel, robust biomarkers that can facilitate precise irAEs diagnosis or prediction. Lastly, this review furnishes a concise exposition of irAEs mechanisms to augment understanding of irAEs prediction, diagnosis, and treatment strategies.

Integrated comparison of the mRNAome in cartilage, synovium, and macrophages in osteoarthritis

The precise molecular mechanisms associated with osteoarthritis (OA), the most common musculoskeletal disorder, are poorly understood. There are currently no effective treatments to prevent the initiation and progression of the disease. In recent years, the development of mRNAome has made it possible to identify new mechanisms and therapeutic targets. However, the differentially expressed genes screened by different microarrays are not completely the same. In order to avoid this shortcoming, we integrate the different genes from different tissues and data sets, and select the commonly expressed genes for further studies.

Semaphorin 5A suppresses ferroptosis through activation of PI3K-AKT-mTOR signaling in rheumatoid arthritis

Abnormal activation of synovial fibroblasts (SFs) plays an important role in rheumatoid arthritis (RA), the mechanism of which remains unknown. The purpose of our study is to comprehensively and systematically explore the mechanism for Semaphorin 5A-mediated abnormal SF activation in RA. Here, we found that Semaphorin 5A levels were significantly higher in synovial fluid and synovial tissue from RA patients compared with osteoarthritis patients. We further found that the mRNA level and protein abundance of Plexin-A1 was elevated in RA SFs compared with OA SFs, while Plexin-B3 expression showed no significant difference. The increased Semaphorin 5A in RA synovial fluid was mainly derived from CD68⁺ synovial macrophages, and the elevation led to increased binding between Semaphorin 5A and its receptors, thereby promoting cytokine secretion, proliferation, and migration, and decreasing apoptosis. Moreover, the effect of Semaphorin 5A on enhancing activation (cytokine secretion, cell proliferation and migration) and reducing apoptosis of SFs was significantly abolished after knockdown of Plexin-A1 and Plexin-B3 by small interfering RNA. Transcriptome sequencing and protein array detection revealed that Semaphorin 5A activated the PI3K/AKT/mTOR signaling pathway and inhibited ferroptosis. Morphologically, transmission electron microscopy results showed that Semaphorin 5A could significantly eliminate the mitochondrial diminution, membrane density increased and crest ruptured of SFs induced by ferroptosis inducer RSL3. Mechanistically, Semaphorin 5A enhanced GPX4 expression and SREBP1/SCD-1 signaling by activating the PI3K/AKT/mTOR signaling pathway, thus suppressing ferroptosis of RA SFs. In conclusion, our study provided the first evidence that elevated Semaphorin 5A in RA synovial fluid promotes SF activation by suppressing ferroptosis through the PI3K/AKT/mTOR signaling pathway.

TSP1 is the essential domain of SEMA5A involved in pannus formation in rheumatoid arthritis

OBJECTIVE

In this study, we explored the effect of semaphorin5A (SEMA5A) on RA pathogenesis and its specific TSP1 domain on pannus formation.

METHODS

The expression of SEMA5A was detected in the synovium, the fibroblast-like synoviocytes (FLSs) and the SF of RA patients and healthy controls (HCs) by real-time quantitative PCR (q-PCR), immunohistochemistry staining, western blot and ELISA. SEMA5A-mAb intervention was performed to appraise the severity of joints in the CIA model. Transcriptome sequencing and bioinformatics analysis in SEMA5A-transfected FLSs from HCs were performed to screen differentially expressed genes after SEMA5A overexpression. An MTT assay in RA-FLSs, a chicken embryo allantoic membrane experiment and a tube formation experiment were used to clarify the influence of SEMA5A on cell proliferation and angiogenesis. Furthermore, a rescue experiment verified the function of the TSP1 domain of SEMA5A in the progress of RA with Sema5a-/- CIA mice.

RESULTS

The expression of SEMA5A increased in RA compared with that in HCs. Simultaneously, SEMA5A-mAbs significantly attenuated joint injury and the inflammatory response in CIA models. In addition, transcriptome sequencing and angiogenesis-related experiments verified the ability of SEMA5A to promote FLS proliferation and angiogenesis. Moreover, TSP1 was proved to be an essential domain in SEMA5A-induced angiogenesis in vitro. Additionally, rescue of TSP1-deleted SEMA5A failed to reduce the severity of arthritis in a CIA model constructed with Sema5a -/- mice.

CONCLUSION

In summary, upregulation of SEMA5A was first confirmed in pathological lesions of RA patients. Furthermore, treatment with SEMA5A-mAbs attenuated the progress of RA in the CIA model. Moreover, TSP1 was indicated as the key domain of SEMA5A in the promotion of pannus formation in RA.

Immune Checkpoint Blockade and Skin Toxicity Pathogenesis

Immune checkpoint blockade has revolutionized the treatment of multiple tumor types, including melanoma and nonmelanoma skin cancers. The use of immune checkpoint blockade is curtailed by tissue toxicities termed immune-related adverse events (irAEs), which occur most quickly and most often in the skin. We review the rationale for immune checkpoint blockade use, current agents, use in skin cancers, autoimmune manifestations in the skin, and considerations for predictive biomarkers and treatment options on the basis of skin pathogenesis. We also highlight major gaps in the field and the lack of preclinical modeling in the skin. A deeper understanding of irAE pathophysiology may help to uncouple toxicity and efficacy but mandates an interdisciplinary approach, including foundational skin immunology and autoimmune pathogenesis.

Genetic determinants of immune-related adverse events in patients with melanoma receiving immune checkpoint inhibitors

BACKGROUND

Immune checkpoint inhibitors (ICIs) can cause profound immune-related adverse events (irAEs). The host genetic background is likely to play a role in irAE susceptibility because the presentation of toxicity varies among patients and many do not develop irAEs despite continued ICI use. We sought to identify potential genetic markers conferring risk for irAEs.

METHODS

We conducted a pilot exploratory study in 89 melanoma patients who received ICIs (44 with irAEs, and 45 without irAEs after at least 1 year from starting treatment). Genotyping was performed using the Infinium Multi-Ethnic Global-8 v1.0 Bead Chip. The genotype data were extracted using PLINK (v1.90b3.34) and processed for quality control. Population structure-based clustering was carried out using IBS matrix, pairwise population concordance test (p < 1 × 10-3), and phenotype distribution for all study participants, resulting in seven population structure-based clusters. In the analytical stage, 599,931 variants in autosomal chromosomes were included for the association study. The association test was performed using an additive genetic model with exact logistic regression, adjusted for age, sex, and population cluster.

RESULTS

A total of 30 variants or single-nucleotide polymorphisms with p < 1 × 10-4 were identified; 12 were associated with an increased risk of irAEs, and the remaining 18 were associated with a decreased risk. Overall, nine of the identified single-nucleotide polymorphisms mapped to eight unique genes that have been associated with autoimmunity or inflammatory diseases.

CONCLUSION

Several genetic variants associated with irAEs were identified. Additional larger studies are needed to validate these findings and establish their potential functional relevance.

The Expression of IL-17, in Chronic Spontaneous Urticaria Is Linked to Semaphorin5A

Background: Patients with chronic spontaneous urticaria (CSU), an autoimmune disorder, show increased skin expression of IL-17A and can benefit from treatment with the anti-IL-17A biologic secukinumab. The mechanisms that drive IL-17A expression in CSU are currently unknown, but may involve Semaphorin5A (Sema5A). Objective: To explore the expression, role, and effects of Sema5A in CSU and its link to IL-17A. Material and Methods: We investigated patients with CSU and healthy controls for skin expression of expressing peripheral T cells. Results: Sema5A was highly expressed in the skin of CSU patients as compared to healthy control skin. Both CD4+ T cells and mast cells in CSU skin expressed Sema5A, and many of them expressed both Sema5A and IL-17A. Patients with CSU had significantly higher rates of IL-17A-expressing CD4+ T cells as compared to healthy controls. Incubation with Sema5A increased the rates of IL-17A-expressing CD4+ T cells in healthy controls to CSU levels. Conclusion: Sema5A may drive the expression and effects of IL-17A in CSU. Further studies in larger cohorts are needed to confirm the role of Sema5A in the pathogenesis of CSU and to explore its potential as a therapeutic target.

High Expression Levels of Long Noncoding RNA Small Nucleolar RNA Host Gene 18 and Semaphorin 5A Indicate Poor Prognosis in Multiple Myeloma

BACKGROUND

The aim of this study was to detect the expression of long noncoding RNA small nucleolar RNA host gene 18 (SNHG18) andsemaphorin 5A (SEMA5A) genes in multiple myeloma (MM) patients and to explore the correlation of the expression of these genes with the clinical characteristics and prognosis of MM patients.

METHODS

Forty-seven newly diagnosed MM, 18 complete remission MM, 13 refractory/relapse MM, and 22 iron deficiency anemia (serving as control) samples were extracted at the Department of Hematology, Second Affiliated Hospital of Xian Jiaotong University between January 2015 and December 2016. The clinical features of the MM patients are summarized. Real-time quantitative PCR was performed to analyze the relative expression levels of the SNHG18 and SEMA5Agenes. The clinical characteristics and overall survival (OS) of the MM patients were statistically analyzed while measuring different levels of SNHG18 and SEMA5Agene expression. At the same time, the correlation between the expression of SNHG18 and SEMA5A was also analyzed.

RESULTS

The analysis confirmed that SNHG18 and its possible target gene SEMA5A were both highly expressed in newly diagnosed MM patients. After analyzing the clinical significance of SNHG18 and SEMA5A in MM patients, we found that the expression of SNHG18 and SEMA5A was related to the Durie-Salmon (DS), International Staging System (ISS), and Revised International Staging System (R-ISS) classification systems, and the Mayo Clinic Risk Stratification for Multiple Myeloma (mSMART; p < 0.05). Moreover, we observed a significant difference in OS between the SNHG18/SEMA5A high expression group and the low expression group. We found a positive correlation between SNHG18 and SEMA5A expression (r = 0.709, p < 0.01). Surprisingly, the expected median OS times of both the SNHG18 and SEMA5Ahigh expression groups were significantly decreased, which was in contrast to those of both the SNHG18 and SEMA5Alow expression groups and the single-gene high expression group (p < 0.05).

CONCLUSION

High expression of both SNHG18 and SEMA5A is associated with poor prognosis in patients with MM.

Role of Semaphorins in Immunopathologies and Rheumatic Diseases

Rheumatic diseases are disorders characterized by joint inflammation, in which other organs are also affected. There are more than two hundred rheumatic diseases, the most studied so far are rheumatoid arthritis, osteoarthritis, spondyloarthritis, systemic lupus erythematosus, and systemic sclerosis. The semaphorin family is a large group of proteins initially described as axon guidance molecules involved in nervous system development. Studies have demonstrated that semaphorins play a role in other processes such as the regulation of immunity, angiogenesis, bone remodeling, apoptosis, and cell migration and invasion. Moreover, semaphorins have been related to the pathogenesis of multiple sclerosis, asthma, Alzheimer, myocarditis, atherosclerosis, fibrotic diseases, osteopetrosis, and cancer. The aim of this review is to summarize current knowledge regarding the role of semaphorins in rheumatic diseases, and discuss their potential applications as therapeutic targets to treat these disorders.

Semaphorin 5A drives melanoma progression: role of Bcl-2, miR-204 and c-Myb

Background

Melanoma, the most aggressive form of skin cancer, is characterized by high rates of metastasis, drug resistance and mortality. Here we investigated the role of Semaphorin 5A (Sema5A) on the properties associated with melanoma progression and the factors involved in Sema5A regulation.

Methods

Western blotting, qRT-PCR, Chromatin immunoprecipitation (ChIP) assay, immunohistochemistry of melanoma patient specimens and xenograft tissues, in vitro Transwell assay for cell migration and invasion evaluation, in vitro capillary-like structure formation analysis.

Results

A significant correlation of Sema5A mRNA expression and melanoma progression was observed by analyzing GEO profile dataset. Endogenous Sema5A protein was detected in 95% of human melanoma cell lines tested, in 70% of metastatic specimens from patients affected by melanoma, and 16% of in situ melanoma specimens showed a focal positivity. We demonstrated that Sema5A regulates in vitro cell migration and invasion and the formation of vasculogenic structures. We also found an increase of Sema5A at both mRNA and protein level after forced expression of Bcl-2. By use of transcriptional and proteasome inhibitors, we showed that Bcl-2 increases the stability of Sema5A mRNA and protein. Moreover, by ChIP we demonstrated that Sema5A expression is under the control of the transcription factor c-Myb and that c-Myb recruitment on Sema5A promoter is increased after Bcl-2 overexpression. Finally, a concomitant decrease in the expression of Sema5A, Bcl-2 and c-Myb proteins was observed in melanoma cells after miR-204 overexpression.

Conclusion

Overall our data provide evidences supporting the role of Sema5A in melanoma progression and the involvement of Bcl-2, miR-204 and c-Myb in regulating its expression.

Electronic supplementary material

The online version of this article (10.1186/s13046-018-0933-x) contains supplementary material, which is available to authorized users.

IL-1 family cytokines and soluble receptors in systemic lupus erythematosus

Background

Dysregulated production of cytokines has a critical role in systemic lupus. The aim of this work is to identify, by a comprehensive analysis of IL-1 family cytokines and receptors in serum, correlation between cytokines/receptors’ levels and the clinical and serological features of the disease.

Methods

A full clinical evaluation was performed in 74 patients with systemic lupus erythematosus (SLE). C3, C4, anti-dsDNA and anti-C1q antibodies were measured. Cytokines of the IL-1 family (IL-1α, IL-1β, IL-33, IL-18), soluble receptors (sIL-1R1, sIL-1R2, sIL-1R3, ST2/sIL-1R4) and antagonists (IL-1Ra, IL-18 binding protein (IL-18BP)) were measured in serum by multiarray ELISA. Free IL-18 was calculated as the amount of IL-18 not inhibited by IL-18BP. Data were analysed by non-parametric tests and by multivariate analysis, using partial least squares (PLS) models.

Results

Total IL-18, IL-18BP, sIL-1R4 and IL-1Ra levels were higher in SLE vs. controls. Total and free IL-18 and sIL-1R4 were higher in patients with active vs. inactive disease and correlated with ECLAM, anti-C1q and anti-dsDNA antibodies. sIL-1R2 was higher in patients with inactive disease, was negatively correlated with ECLAM and anti-C1q antibodies and was positively correlated with C3 levels. PLS identified sIL-1R4, sIL-1R2 and anti-dsDNA as variables distinguishing patients with active from those with inactive disease; sIL-1R4, IL-18BP and anti-dsDNA identified patients with active nephritis; sIL-1R4, C3, IL-18 and free IL-18 identified patients with haematological involvement.

Conclusion

The data support the use of IL-18, sIL-1R2 and sIL-1R4 as biomarkers of disease activity and organ involvement, and suggest that failure in the inhibition of IL-1 activation may be a critical event in the active stages of SLE.

Elevated semaphorin 5A in patients with Hashimoto's thyroiditis: a case-control study

OBJECTIVE

Hashimoto's thyroiditis (HT) is characterized by elevated specific auto-antibodies, including TgAb and TPOAb. Increasing evidence has demonstrated the essential role of Th17 cells in HT. However, the underlying mechanism is still unclear. Semaphorin 5A (Sema 5A) is involved in several autoimmune diseases through the regulation of immune cells. The aim of the present study was to explore the role of Sema 5A in HT.

METHODS

We measured serum Sema 5A levels in HT (n = 92) and healthy controls (n = 111) by enzyme-linked immunosorbent assay (ELISA). RNA levels of Sema 5A and their receptors (plexin-A1 and plexin-B3), as well as several cytokines (IFN-γ, IL-4 and IL-17), were detected by real-time polymerase chain reaction in peripheral blood mononuclear cells from 23 patients with HT and 31 controls. In addition, we investigated the relationship between serum Sema 5A and HT.

RESULTS

Serum Sema 5A in HT increased significantly compared with healthy controls (P < 0.001). Moreover, serum Sema 5A levels were positively correlated with TgAb (r = 0.511, P < 0.001), TPOAb (r = 0.423, P < 0.001), TSH (r = 0.349, P < 0.001) and IL-17 mRNA expression (r = 0.442, P < 0.001). Increased Sema 5A RNA expression was observed (P = 0.041) in HT compared with controls. In receiver-operating characteristic (ROC) analysis, serum Sema 5A predicted HT with a sensitivity of 79.35% and specificity of 96.40%, and the area under the curve of the ROC curve was 0.836 (95% CI: 0.778-0.884, P < 0.001).

CONCLUSIONS

These data demonstrated elevated serum Sema 5A in HT patients for the first time. Serum Sema 5A levels were correlated with thyroid auto-antibodies and IL-17 mRNA expression. Sema 5A may be involved in immune response of HT patients.