Upregulated survivin expression in activated T lymphocytes correlates with disease activity in multiple sclerosis

Single-Cell Analysis of CX3CR1+ Cells Reveals a Pathogenic Role for BIRC5+ Myeloid Proliferating Cells Driven by Staphylococcus aureus Leukotoxins

Our previous studies identified a population of stem cell-like proliferating myeloid cells within inflamed tissues that could serve as a reservoir for tissue macrophages to adopt different activation states depending on the microenvironment. By lineage-tracing cells derived from CX3CR1+ precursors in mice during infection and profiling by single-cell RNA sequencing, in this study, we identify a cluster of BIRC5+ myeloid cells that expanded in the liver during chronic infection with either the parasite Schistosoma mansoni or the bacterial pathogen Staphylococcus aureus. In the absence of tissue-damaging toxins, S. aureus infection does not elicit these BIRC5+ cells. Moreover, deletion of BIRC5 from CX3CR1-expressing cells results in improved survival during S. aureus infection. Hence the combination of single-cell RNA sequencing and genetic fate-mapping CX3CR1+ cells revealed a toxin-dependent pathogenic role for BIRC5 in myeloid cells during S. aureus infection.

Single-cell analysis of CX3CR1 + cells reveal a pathogenic role for BIRC5 + myeloid proliferating cells driven by Staphylococcus aureus leukotoxins

Our previous studies identified a population of stem cell-like proliferating myeloid cells within inflamed tissues that could serve as a reservoir for tissue macrophages to adopt different activation states depending on the microenvironment. By lineage tracing cells derived from CX3CR1 + precursors in mice during infection and profiling by scRNA-seq, here we identify a cluster of BIRC5 + myeloid cells that expanded in the liver during either chronic infection with the parasite Schistosoma mansoni or the bacterial pathogen Staphylococcus aureus . In the absence of tissue damaging toxins, S. aureus infection does not elicit these BIRC5 + cells. Moreover, deletion of BIRC5 from CX3CR1 expressing cells results in improved survival during S. aureus infection. Hence, the combination of scRNA-Seq and genetic fate mapping CX3CR1 + cells revealed a toxin dependent pathogenic role for BIRC5 in myeloid cells during S. aureus infection.

Contribution of survivin to the immune system, allergies and autoimmune diseases

In addition to malignancies, survivin (a member of the apoptosis inhibitor family) has been implicated in the pathogenesis of inflammatory disorders, including autoimmune and allergic diseases. Survivin is constantly expressed in the proliferating hematopoietic progenitor cells, and it is re-expressed in the mature cells of the innate and adaptive immunity, upon activation. Survivin enhances the expression of co-stimulatory molecules and MHC class II molecules in dendritic cells, and promotes the lifespan of macrophages, neutrophils, and eosinophils, while suppressing natural killer (NK) cell activity. Survivin has been implicated in T cell maturation, T cell expansion, effector CD4⁺ T cell differentiation, maintenance of memory CD4⁺ T and CD8⁺ T cells, as well as antibody production. Upregulated expression of survivin was indicated in the T cells as well as various samples collected from allergic patients. Survivin can contribute to the pathogenesis of allergic diseases via the promotion of the Th2 polarization, promoting IL-4 expression, compromising activation-induced cell death (AICD) in Th2 cells, and preventing apoptosis of eosinophils, as well as, amplification of eosinophilia. Moreover, survivin can interfere with clonal deletion of autoreactive T and B cells, as well as suppress Treg cell development and activity supporting the development of autoimmune diseases. This review discusses the role of survivin in immunity, allergy and autoimmunity as well as provides evidence that survivin may be considered as a novel therapeutic target for the treatment of allergic and autoimmune diseases.

The Behaviour of Serum Survivin in Patients With Lupus Nephritis

Background:

Systemic lupus erythematosus (SLE) is a chronic, multi phenotypic, autoimmune inflammatory disease and renal involvement significantly worsens its prognosis. Apoptosis dysregulation plays a key pathogenic role. Survivin, a protein from the apoptosis inhibitors family, has been considered a promising strategy in cancer therapy and evaluated as one of the regulatory pathways in the scenario of immune-mediated disorders.

Objective:

This study aims to explore survivin behaviour in SLE patients with lupus nephritis (LN), assessing its potential as a therapeutic and prognostic biomarker.

Methods:

297 SLE patients were classified based on the American College of Rheumatology (ACR) 1997 criteria, from 2000 to 2015. In a cross-sectional study, the serum level of survivin was measured by an ELISA test and compared between 200 SLE individuals and healthy controls. In a longitudinal cohort, 97 patients with active LN had the concentration of survinin measured, before and after treatment with cyclophosphamide pulse therapy.

Results:

The serum concentration of survivin was significantly lower in the SLE group than in healthy controls, regardless of concomitant NL or disease activity. The longitudinal evaluation revealed a significant reduction in survivin serum level after treatment. However, survivin rates were not able to discriminate groups that achieved remission from those that maintained nephritis activity.

Conclusion:

Our study suggests that survivin levels in SLE patients are lower than in the general population. Even so, its use as a biomarker in SLE seems limited, not reflecting disease activity or response to LN treatment, as in other contexts.

A Scoping Review on Body Fluid Biomarkers for Prognosis and Disease Activity in Patients with Multiple Sclerosis

Multiple sclerosis (MS) is a complex demyelinating disease of the central nervous system, presenting with different clinical forms, including clinically isolated syndrome (CIS), which is a first clinical episode suggestive of demyelination. Several molecules have been proposed as prognostic biomarkers in MS. We aimed to perform a scoping review of the potential use of prognostic biomarkers in MS clinical practice. We searched MEDLINE up to 25 November 2021 for review articles assessing body fluid biomarkers for prognostic purposes, including any type of biomarkers, cell types and tissues. Original articles were obtained to confirm and detail the data reported by the review authors. We evaluated the reliability of the biomarkers based on the sample size used by various studies. Fifty-two review articles were included. We identified 110 molecules proposed as prognostic biomarkers. Only six studies had an adequate sample size to explore the risk of conversion from CIS to MS. These confirm the role of oligoclonal bands, immunoglobulin free light chain and chitinase CHI3L1 in CSF and of serum vitamin D in the prediction of conversion from CIS to clinically definite MS. Other prognostic markers are not yet explored in adequately powered samples. Serum and CSF levels of neurofilaments represent a promising biomarker.

Survivin; a novel therapeutic target that correlates with survival of autoreactive T lymphocytes obtained from patients with ankylosing spondylitis

Ankylosing spondylitis (AS) is progressive immune-mediated arthritis. Persistent autoreactivity of T cells with an up-regulated Survivin expression is strongly implicated in AS immunopathogenesis. Besides, Survivin can inhibit proapoptotic caspase 9 activations. Moreover, microRNAs are small non-coding RNAs that are dysregulated in various diseases, in which their altered expression could modulate Survivin expression. The primary goal of this study was to assess the role of Survivin and its-targeting microRNAs in the immunopathogenesis of AS disease. For this aim, peripheral blood mononuclear cells (PBMCs) were isolated from 15 patients with AS and healthy matched controls using Ficoll-Hypaque. T cells were obtained using the magnetic-activated cell sorting (MACS) method. After that, the expression levels of Survivin, Caspase 9, and specific miRNAs were determined using qT-qPCR. Also, the expression of Survivin and Caspase 9 at protein levels was determined by western blotting. Then, the isolated T cells were co-cultured with interleukin (IL)-2 and muromonab-CD3 (OKT-3) for active-induced cell death (AICD) induction, Survivin siRNA for inhibition of Survivin expression, and their combination to assess the implication of Survivin expression in autoreactive T lymphocytes' resistance to apoptosis by determining the rate of apoptosis by Flowcytometry assay. The results showed that Survivin was up-regulated while Caspase 9 was downregulated in patients with AS. It was also revealed that microRNAs that directly or indirectly target the Survivin mRNA were dysregulated in patients with AS. It was also revealed that T cells obtained from AS patients were more resistant to apoptosis induction than those obtained from healthy people. In summary, the results obtained from this study showed that dysregulation of Survivin and Survivin-targeting miRNAs in T lymphocytes obtained from AS patients contribute to their resistance to apoptosis, suggesting the future development of targeted therapies for AS.

A computational model revealing the immune-related hub genes and key pathways involved in rheumatoid arthritis (RA)

Rheumatoid arthritis (RA) has one of the highest disability rates among inflammatory joint disorders. However, the reason and possible molecular events are still unclear. There are various treatment options available, but no complete cure. To obtain early diagnosis and successful medication in RA, it is necessary to explore gene susceptibility and pathogenic factors. The main intend of our work is to explore the immune-related hub genes with similar functions that are differentially expressed in RA patients. Three datasets such as GSE21959, GSE55457, and GSE77298, were taken to analyze the differently expressed genes (DEGs) among 55 RA and 33 control samples. We obtained 331 upregulated and 275 downregulated DEGs from three Gene Expression Omnibus (GEO) datasets using the R package. Furthermore, a protein-protein interaction network was built for upregulated and downregulated DEGs using Cytoscape. Subsequently, MCODE analysis was performed and obtained the top two modules in each DEG's upregulated and downregulated protein-protein interactions (PPIs) network. CytoNCA and cytoHubba were performed and identified overlapping DEGs. In addition, we narrowed down DEGs by filtering with immune-related genes and identified DE-IRGs. Gene ontology (GO) and KEGG pathway analysis in upregulated and downregulated DEGs were executed with the DAVID platform. Our study obtained the nine most significant DE-IRGs in RA such as CXCR4, CDK1, BUB1, BIRC5, AGTR1, EGFR, EDNRB, KALRN, and GHSR. Among them, CXCR4, CDK1, BUB1, and BIRC5 are overexpressed in RA and may contribute to the pathophysiology of the disease. Similarly, AGTR1, EGFR, EDNRB, KALRN, and GHSR are all low expressed in RA and may have a contribution to pathogenesis. GO, KEGG functional enrichment, and GeneMANIA showed that the dysregulated process of DE-IRGs causes RA development and progression. These findings may be helpful in future studies in RA diagnosis and therapy.

Dysregulation of Survivin-Targeting microRNAs in Autoimmune Diseases: New Perspectives for Novel Therapies

It has been well established that the etiopathogenesis of diverse autoimmune diseases is rooted in the autoreactive immune cells' excessively proliferative state and impaired apoptotic machinery. Survivin is an anti-apoptotic and mitotic factor that has sparked a considerable research interest in this field. Survivin overexpression has been shown to contribute significantly to the development of autoimmune diseases via autoreactive immune cell overproliferation and apoptotic dysregulation. Several microRNAs (miRNAs/miRs) have been discovered to be involved in survivin regulation, rendering the survivin-miRNA axis a perspective target for autoimmune disease therapy. In this review, we discuss the role of survivin as an immune regulator and a highly implicated protein in the pathogenesis of autoimmune diseases, the significance of survivin-targeting miRNAs in autoimmunity, and the feasibility of targeting the survivin-miRNA axis as a promising therapeutic option for autoimmune diseases.

The Presence of Survivin on B Cells from Myasthenia Gravis Patients and the Potential of an Antibody to a Modified Survivin Peptide to Alleviate Weakness in an Animal Model

Myasthenia gravis (MG) is an autoimmune disease in which Abs target neuromuscular junction proteins, in particular the acetylcholine receptor. We previously identified the antiapoptotic protein survivin in the autoreactive B cells and plasma cells of MG patients. To further define the role of survivin in MG, we have assessed PBMCs from 29 patients with MG and 15 controls. We confirmed the increased expression of survivin in CD20⁺ lymphocytes from MG patients compared with controls. Furthermore, the CD20⁺ population of cells from MG patients contained a higher percentage of extracellular survivin compared with controls. The analysis of CD4⁺ cells showed an increased percentage of intracellular survivin in MG patients compared with controls, whereas the extracellular survivin CD4⁺ percentage was unaffected. In an experimental mouse model of MG, we assessed the therapeutic potential of an Ab raised to a modified survivin peptide but cross-reactive to survivin. Ab treatment reduced disease severity, lowered acetylcholine receptor-specific Abs, and decreased CD19⁺ survivin⁺ splenocytes. The ability to target survivin through Ab recognition of autoreactive cells offers the potential for a highly specific therapeutic agent for MG.

Dysregulation of microRNAs regulating survivin in CD4+ T cells in multiple sclerosis

BACKGROUND

Impaired elimination mechanisms of the autoreactive lymphocytes, like T lymphocytes, via apoptosis may be the cause of continues inflammatory state in multiple sclerosis (MS). BIRC5 gene codify for the survivin, which participates in the modulation of apoptosis and cell survival. The objective of this study was investigation of the role of important confirmed miRNAs, including miR-335, miR-485, miR-542, and miR-708, in the regulation of survivin mRNA in the CD4+ T cells of MS cases.

METHODS

In this study, 50 RRMS patients as well as 50 healthy matched controls were recruited. The peripheral blood mononuclear cells (PBMCs) were isolated from whole blood samples and CD4+ T cells were prepared. After that, RNA was extracted, cDNA was synthesized, and the expression levels of miR-335, miR-485, miR-542, and miR-708 were measured using Real-time PCR. Moreover, the mRNA expression of survivin was detected. Serum level of survivin was detected using ELISA.

RESULTS

The mRNA of survivin was 2-folds upregulated in the CD4+ T cells from MS patients in comparison to the healthy controls (P = 0.0053). Serum level of survivin was higher in patients than controls. There was statistically significant downregulation of miR-485 (P = 0.001) and miR-708 (P = 0.011) in CD4+ T cells of patients compared with controls. The miR-485 downregulation had statistically significant correlation with the mRNA expression and serum level of survivin.

CONCLUSION

miRNAs play a role in the regulation of survivin, and therefore apoptosis of CD4+ T cells, and hence are probably participating in a persistent inflammatory condition in MS patients.

Polymorphisms of BIRC5 Gene is Associated with Chronic HBV Infection in Iranian Population

Survivin can affect the progression of infection and is considered as a marker of various malignancies. The aim of the study was to investigate the possible association of gene polymorphisms of survivin (-1547A/G, -644C/T, -625 C/G, -241C/T, -31G/C, -141G/C) and chronic hepatitis B infection in Iranian patients. The genotypes of survivin SNPs were investigated by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method using 100 chronic HBV infected patients (HBV), 40 spontaneously recovered HBV subjects and 100 healthy controls (C). Serum level of survivin was determined using ELISA method. The -1547G, -625C, -241T and -31C alleles were associated with increased susceptibility to chronic hepatitis B infection (P = 0.001, P < 0.001, P = 0.003 and P < 0.001 respectively). Chronic HBV patients with -625CC, -241TT and -31CC genotypes had higher levels of survvin. Survivin -1547A/G, -625 C/G, -241C/T and -31G/C gene polymorphisms may be associated with chronic HBV susceptibility in Iranian HBV patients.

Phosphorylation Modulates Survivin Function in Behcet's Disease

Purpose: Survivin is critical for proliferation, maturation, homeostasis and differentiation of effector and memory lymphocytes. In this study the baculoviral inhibitors of apoptosis proteins (IAPs) repeat containing 5 (BIRC5) mRNA, survivin, and phosphorylated survivin expression were evaluated in peripheral blood mononuclear cells (PBMCs), and plasma of patients with Behcet’s disease (BD).

Methods: In this study, 26 Iranian Azari patients diagnosed with BD and 30 healthy controls were recruited. Total RNA was extracted from PBMCs. The expression level of survivin was measured by quantitative real-time polymerase chain reaction (PCR). Survivin plasma levels were measured using survivin Enzyme-linked immunosorbent assays. Also, western blotting analysis was performed to measure phosphorylated-survivin and survivin levels in PBMCs and plasma of patients with BD.

Results: In a pilot study, we showed that BIRC5 gene expression increased in BD patients compared with healthy controls (P<0.05). Western blotting analysis indicated that there was an increase in phosphorylated survivin expression in PBMCs of BD patients. Our data from western blot analysis showed survivin level in plasma samples of BD patients was similar to healthy controls. No significant differences were observed between plasma survivin levels in the BD patients compared with control group (P>0.05). The expression of phosphorylated survivin at Thr34 in PBMCs of BD patients with active disease was increased. Plasma phosphorylated survivin levels in having BD patients were also downregulated compared to healthy individuals.

Conclusion: Analysis of PBMCs indicated increasing expression level of phosphorylated survivin in PBMCs of BD patients. There was also a downregulation in phosphorylated survivin levels in plasma of BD patients.

Environmental Influencers, MicroRNA, and Multiple Sclerosis

Multiple sclerosis (MS) is a complex neurological disorder characterized by an aberrant immune system that affects patients' quality of life. Several environmental factors have previously been proposed to associate with MS pathophysiology, including vitamin D deficiency, Epstein-Barr virus (EBV) infection, and cigarette smoking. These factors may influence cellular molecularity, interfering with cellular proliferation, differentiation, and apoptosis. This review argues that small noncoding RNA named microRNA (miRNA) influences these factors' mode of action. Dysregulation in the miRNAs network may deeply impact cellular hemostasis, thereby possibly resulting in MS pathogenicity. This article represents a literature review and an author's theory of how environmental factors may induce dysregulations in the miRNAs network, which could ultimately affect MS pathogenicity.

Genetic polymorphisms and epigenetic regulation of survivin encoding gene, BIRC5, in multiple sclerosis patients

Background

The persistent the inflammatory condition in multiple sclerosis (MS) may due to the aberrant regulation of the elimination of the pathogenic autoreactive lymphocytes through apoptosis. Survivin, encoded by the BIRC5 gene, has been indicated to be involved in the regulation of apoptosis. This survey intended to investigate the genetic and microRNA mediated regulation of survivin in relapsing-remitting MS (RRMS) disease.

Results

It was observed that the C allele (OR = 1.38, 95% CI = 1.05–1.348, P = 0.022) and CC genotype (OR = 1.84, 95% CI = 1.06–3.19; P = 0.029) in the rs9904341 polymorphism increased the disease risk. Furthermore, miR-34a was significantly downregulated (Fold change = 0.41, P = 0.001) in the PBMCs from RRMS subjects. Survivin mRNA expression in PBMCs and serum survivin level were increased in RRMS patients in comparison to the controls. Downregulation of miR-34a was negatively correlated with increased survivin level.

Conclusion

Although the genetic polymorphism of BIRC5 gene was associated with the disease risk, miR-34a was suggested to be involved in the regulation of survivin in the RRMS patients.

Neurotoxic potential of reactive astrocytes in canine distemper demyelinating leukoencephalitis

Canine distemper virus (CDV) causes a fatal demyelinating leukoencephalitis in young dogs resembling human multiple sclerosis. Astrocytes are the main cellular target of CDV and undergo reactive changes already in pre-demyelinating brain lesions. Based on their broad range of beneficial and detrimental effects in the injured brain reactive astrogliosis is in need of intensive investigation. The aim of the study was to characterize astrocyte plasticity during the course of CDV-induced demyelinating leukoencephalitis by the aid of immunohistochemistry, immunofluorescence and gene expression analysis. Immunohistochemistry revealed the presence of reactive glial fibrillary acidic protein (GFAP)+ astrocytes with increased survivin and reduced aquaporin 4, and glutamine synthetase protein levels, indicating disturbed blood brain barrier function, glutamate homeostasis and astrocyte maladaptation, respectively. Gene expression analysis revealed 81 differentially expressed astrocyte-related genes with a dominance of genes associated with neurotoxic A1-polarized astrocytes. Accordingly, acyl-coA synthetase long-chain family member 5+/GFAP+, and serglycin+/GFAP+ cells, characteristic of A1-astrocytes, were found in demyelinating lesions by immunofluorescence. In addition, gene expression revealed a dysregulation of astrocytic function including disturbed glutamate homeostasis and altered immune function. Observed findings indicate an astrocyte polarization towards a neurotoxic phenotype likely contributing to lesion initiation and progression in canine distemper leukoencephalitis.

Survivin modulatory role in autoimmune and autoinflammatory diseases

Baculoviral IAP repeat containing 5 (BIRC5) gene encodes the important protein as survivin, a multifunctional protein, which is involved in cellular and molecular networks, progression of cell cycle, homeostasis, developmental morphogenesis, and apoptosis. The proximal BIRC5 promoter possesses specific binding sites for key transcription factors such as nuclear factor κB and signal transducer and activator of transcription 3. Upregulation of survivin exacerbates the autoimmune diseases (AIDs) including multiple sclerosis and myasthenia gravis by reducing the activity threshold of survivin-specific cytotoxic T cells. DNA damage along with upregulation or downregulation of survivin have been demonstrated in initiation and pathogenesis of cancers and AIDs. However, detailed mechanism of survivin function in pathogenesis of AIDs is not well understood. This review focuses on the structure, specificity, regulation, and function of survivin in physiologic conditions and pathogenesis of AIDs.

Evaluation of immunohistochemical expression of survivin and its correlation with -31G/C gene polymorphism in colorectal cancer

Colorectal cancer (CRC) placed among the most common neoplasm. Survivin is a member of the inhibitor apoptosis gene family. This gene could be associated with aggressive behavior in numerous types of cancers. The aim of the present study was to evaluate the immunohistochemical expression of survivin gene and its correlation with -31G/C polymorphism in CRC patients. This case-control study was performed on 90 cases: 30 adenocarcinoma, 30 adenomatous polyp, and 30 normal colon. Immunohistochemical expression of survivin evaluated on formalin-fixed paraffin-embedded tissue and -31G/C polymorphism was analyzed by polymerase chain reaction-restriction fragment length polymorphism analysis. Results showed that the subjects carrying C/C genotype with 43.3% (p = 0.002' OR = 12.188, CI = 2.530-58.720) and G/C genotype with 43.3% (p = 0.032' OR = 4.432, CI = 1.133-17.341) significantly had increased risk of CRC compared with subjects carrying GG genotype. Allelic frequencies showed statistically significant difference (p = 0.001) among adenocarcinoma (G = 35%, C = 65%), adenomatous (G = 43.3, C = 56.7), and normal group (G = 68.3, C = 31.7). Immunohistological evaluation showed nuclear survivin protein expression in patients with the CC genotype higher than in patient with the GG and GC genotypes (p = 0.002). The results suggest that C allele of - 31G/C polymorphism in survivin might be cooperative in CRC development.

Survivin in autoimmune diseases

Survivin is a protein functionally important for cell division, apoptosis, and possibly, for micro-RNA biogenesis. It is an established marker of malignant cell transformation. In non-malignant conditions, the unique properties of survivin make it indispensable for homeostasis of the immune system. Indeed, it is required for the innate and adaptive immune responses, controlling differentiation and maintenance of CD4⁺ and CD8⁺ memory T-cells, and in B cell maturation. Recently, survivin has emerged as an important player in the pathogenesis of autoimmune diseases. Under the conditions of unreserved inflammation, survivin enhances antigen presentation, maintains persistence of autoreactive cells, and supports production of autoantibodies. In this context, survivin takes its place as a diagnostic and prognostic marker in rheumatoid arthritis, psoriasis, systemic sclerosis and pulmonary arterial hypertension, neuropathology and multiple sclerosis, inflammatory bowel diseases and oral lichen planus. In this review, we summarise the knowledge about non-malignant properties of survivin and focus on its engagement in cellular and molecular pathology of autoimmune diseases. The review highlights utility of survivin measures for clinical applications. It provides rational for the survivin inhibiting strategies and presents results of recent reports on survivin inhibition in modern therapies of cancers and autoimmune diseases.

Blood Biomarkers as Outcome Measures in Inflammatory Neurologic Diseases

Multiple sclerosis (MS) is an autoimmune demyelinating disorder of the central nervous system. Only a few biomarkers are available in MS clinical practice, such as cerebrospinal fluid oligoclonal bands and immunoglobulin index, serum anti-aquaporin 4 antibodies, and serum anti-John Cunningham virus antibodies. Thus, there is a significant unmet need for biomarkers to assess prognosis, response to therapy, or potential treatment complications. Here we describe emerging biomarkers that are in development, focusing on those from peripheral blood. There are several limitations in the process of discovery and validation of a good biomarker, such as the pathophysiological complexity of MS and the technical difficulties in globally standardizing methods for sampling, processing, and conserving biological specimens. In spite of these limitations, ongoing international collaborations allow the exploration of many interesting molecules and markers to validate diagnostic, prognostic, and therapeutic-response biomarkers.

Peripheral blood biomarkers in multiple sclerosis

Multiple sclerosis is the most common autoimmune disorder affecting the central nervous system. The heterogeneity of pathophysiological processes in MS contributes to the highly variable course of the disease and unpredictable response to therapies. The major focus of the research on MS is the identification of biomarkers in biological fluids, such as cerebrospinal fluid or blood, to guide patient management reliably. Because of the difficulties in obtaining spinal fluid samples and the necessity for lumbar puncture to make a diagnosis has reduced, the research of blood-based biomarkers may provide increasingly important tools for clinical practice. However, currently there are no clearly established MS blood-based biomarkers. The availability of reliable biomarkers could radically alter the management of MS at critical phases of the disease spectrum, allowing for intervention strategies that may prevent evolution to long-term neurological disability. This article provides an overview of this research field and focuses on recent advances in blood-based biomarker research.

Association of survivin promoter polymorphisms with inflammatory bowel disease and response to antitumor necrosis factor therapy

BACKGROUND/AIM

Recent evidence suggests that survivin, a member of the inhibitors of apoptosis family that prevents cell death and regulates cell division is implicated in the pathogenesis of inflammatory bowel disease (IBD). The aim of the study was to identify a possible association between individual genetic variation, IBD susceptibility, and response to infliximab (IFX).

MATERIAL AND METHODS

The expression levels of survivin were detected in pathologic areas of fresh tissues and blood samples by real-time reverse transcriptase - polymerase chain reaction (RT-PCR) from IBD patients. Polymorphisms were identified using the polymerase chain reaction - Restriction Fragment Length Polymorphism (PCR-RFLP) technique. Clinical and endoscopic response to IFX was evaluated by ileocolonoscopy performed at baseline and after 12-20 weeks of therapy with patients classified as either responders or nonresponders.

RESULTS

No significant differences were found between survivin mRNA levels between patients and controls. Significant differences in both allele and genotype frequencies between Crohn's disease (CD) and ulcerative colitis (UC) patients and controls were found in -31C/G polymorphism. No association with IBD development was found for the -625G/C and -241T/C polymorphisms, since those polymorphisms were overrepresented in a healthy population. Additionally no significant association was found between -31C/G polymorphism and the clinical response of CD patients to IFX.

CONCLUSIONS

Survivin promoter polymorphism -31C/G might influence the susceptibility to IBD in the Greek population, but not the CD patient's response to anti-TNF drugs.

Survivin as a potential mediator to support autoreactive cell survival in myasthenia gravis: a human and animal model study

The mechanisms that underlie the development and maintenance of autoimmunity in myasthenia gravis are poorly understood. In this investigation, we evaluate the role of survivin, a member of the inhibitor of apoptosis protein family, in humans and in two animal models. We identified survivin expression in cells with B lymphocyte and plasma cells markers, and in the thymuses of patients with myasthenia gravis. A portion of survivin-expressing cells specifically bound a peptide derived from the alpha subunit of acetylcholine receptor indicating that they recognize the peptide. Thymuses of patients with myasthenia gravis had large numbers of survivin-positive cells with fewer cells in the thymuses of corticosteroid-treated patients. Application of a survivin vaccination strategy in mouse and rat models of myasthenia gravis demonstrated improved motor assessment, a reduction in acetylcholine receptor specific autoantibodies, and a retention of acetylcholine receptor at the neuromuscular junction, associated with marked reduction of survivin-expressing circulating CD20+ cells. These data strongly suggest that survivin expression in cells with lymphocyte and plasma cell markers occurs in patients with myasthenia gravis and in two animal models of myasthenia gravis. Survivin expression may be part of a mechanism that inhibits the apoptosis of autoreactive B cells in myasthenia gravis and other autoimmune disorders.

Arsenic and fluoride co-exposure affects the expression of apoptotic and inflammatory genes and proteins in mononuclear cells from children

Humans may be exposed to arsenic (As) and fluoride (F) through water consumption. However, the interaction between these two elements and gene expression in apoptosis or inflammatory processes in children has not been thoroughly investigated. Herein, the expression of cIAP-1, XIAP, TNF-α, ENA-78, survivin, CD25, and CD40 was evaluated by RT-PCR. Additionally, the surface expression of CD25, CD40, and CD40L on peripheral blood mononuclear cells was analyzed by flow cytometry, and TNF-α was measured by Western blotting. This study examined 72 children aged 6-12 years who were chronically exposed to As (154.2μg/L) and F (5.3mg/L) in drinking water and in food cooked with the same water. The urine concentrations of As (6.9-122.4μg/L) were positively correlated with the urine concentrations of F (1.0-8.8mg/L) (r(2)=0.413, p<0.0001). The CD25 gene expression levels and urine concentrations of As and F were negatively correlated, though the CD40 expression levels were negatively correlated only with the As concentration. Age and height influenced the expression of cIAP-1, whereas XIAP expression was correlated only with age. Additionally, there was a lower percentage of CD25- and CD40-positive cells in the group of 6- to 8-year-old children exposed to the highest concentrations of both As and F when compared to the 9- to 12-year-old group (CD25: 0.7±0.8 vs. 1.1±0.9, p<0.0014; CD40: 16.0±7.0 vs. 21.8±5.8, p<0.0003). PHA-stimulated lymphocytes did not show any changes in the induction of CD25, CD69, or CD95. In summary, high concentrations of As and F alter the expression patterns of CD25 and CD40 at both the genetic and protein levels. These changes could decrease immune responses in children exposed to As and F.

Increased levels of survivin, via association with heat shock protein 90, in mucosal T cells from patients with Crohn's disease

BACKGROUND & AIMS

Defective apoptosis of lamina propria T cells (LPTs) is involved in the pathogenesis of Crohn's disease. Survivin, a member of the inhibitors of apoptosis family, prevents cell death and regulates cell division. Survivin has been studied extensively in cancer, but little is known about its role in Crohn's disease.

METHODS

LPTs were isolated from mucosal samples of patients with Crohn's disease or ulcerative colitis and healthy individuals (controls). LPTs were activated with interleukin-2 or via CD3, CD2, and CD28 signaling, and cultured at 42°C to induce heat shock. Survivin expression was assessed by immunohistochemistry, confocal microscopy, and immunoblotting; survivin levels were reduced by RNA interference. Cell viability, apoptosis, and proliferation were measured by trypan blue exclusion, annexin-V/7-Aminoactinomycin D staining, and uptake of [3]thymidine, respectively.

RESULTS

LPTs from patients with Crohn's disease had higher levels of survivin than LPTs from patients with ulcerative colitis or controls. RNA knockdown of survivin in LPTs inhibited their proliferation and promoted apoptosis. Levels of survivin were low in LPTs from patients with ulcerative colitis and controls as a result of ubiquitin-mediated proteasome degradation. In LPTs from patients with Crohn's disease, survivin bound to the heat shock protein (HSP)90, and therefore was resistant to proteasome degradation. Incubating LPTs with 17-N-allylamino-17-demethoxygeldanamycin, an inhibitor of HSP90, reduced levels of survivin and induced apoptosis.

CONCLUSIONS

Levels of survivin are increased in LPTs from patients with Crohn's disease (compared with ulcerative colitis and controls) because survivin interacts with HSP90 and prevents proteasome degradation. This allows LPTs to avoid apoptosis. Strategies to restore apoptosis to these cells might be developed to treat patients with Crohn's disease.

Novel survivin mutant protects differentiated SK-N-SH human neuroblastoma cells from activated T-cell neurotoxicity

Currently, there are no known treatments for protection of axonal loss associated with neuroinflammatory diseases such as multiple sclerosis (MS). Survivin is a member of the inhibitors of the apoptosis (IAP) family of proteins that its neuroprotective effects have not been studied. We demonstrate here that SurR9-C84A, a survivin mutant, exhibits a neuroprotective role against the cytotoxic effects of activated T-cell infiltrates, such as granzyme B (GrB). The activated T-cell supernatants induce toxicity on differentiated SK-N-SH cells, which is associated with the loss of Ca(2+) homeostasis, the increased population of dead cells, mitochondrial membrane depolarisation, and the accelerated expression of cyclinD1, caspase3 and Fas, as observed for most apoptotic cells. Alternatively, the pre-treatment with SurR9-C84A reduces the population of dead cells by balancing the cytosolic Ca(2+) homeostasis, decreasing the level of mitochondrial depolarisation, and also reducing the expression of cyclinD1 and caspase3. Our findings suggest that SurR9-C84A has a neuroprotective effect against the cytotoxins existing in activated T-cell supernatants including GrB.

Pattern of expression of apoptosis and inflammatory genes in humans exposed to arsenic and/or fluoride

We have assessed whether the combined exposure to arsenic (As) and fluoride (F) exerts a different effect than the exposure to As alone on the pattern of expression of apoptosis and inflammatory genes by immune cells. RNA was extracted from peripheral blood mononuclear cells from twenty individuals exposed or not to As or F or both. Then, cDNA was isolated, and the expression of 180 genes related to apoptosis and inflammation was tested by a cDNA array test. We found significant differences in the expression of 9 apoptosis and 15 inflammation genes in the three exposed groups compared to non-exposed individuals. In addition, subjects exposed to As or F or both showed different patterns of expression of at least 19 genes. Our data indicate that the combined exposure to As and F has a different effect on gene expression than the exposure to As or F alone.

Impaired Expression of Peripheral Blood Apoptotic-Related Gene Transcripts in Acute Multiple Sclerosis Relapse

Differential expression of apoptotic genes may influence the susceptibility of activated lymphocytes to expand and induce acute relapse and persistent inflammation in patients with relapsing-remitting multiple sclerosis (RRMS). The exact relationship between alterations in apoptotic-related gene expression and clinical disease activity has not been broadly evaluated. In this study we studied peripheral blood mononuclear cells (PBMCs) expression of pro- and antiapoptotic genes in RRMS patients during acute relapse in comparison to patients in remission. Using cDNA Affymetrix microarrays platform (U133A2 microarrays) we analyzed the gene expression profile of PBMC derived from 22 RRMS patients in acute relapse (15 females, mean age 34.6 +/- 1.8 years, disease duration 5.6 +/- 0.8 years) in comparison to 20 sex- and age-matched RRMS patients in remission. One thousand five hundred seventy-eight gene transcripts significantly differentiated acute multiple sclerosis (MS) relapse from remission. This characteristic gene expression signature was enriched by an apoptotic-related pathway. The 1578 gene transcripts that significantly differentiated acute relapse from remission were enriched by 55 apoptotic-related genes in that reflected different operating pathways during the acute phase of the disease. These genes mainly involved the caspase-dependent pathway and included overexpression of the negative regulator of FAS-induced apoptosis (TOSO) and the BCL2 antiapoptotic family members (BCL2, BCL2 AA) as well as downexpression of proapoptotic genes like BAX, apoptotic protease-activating factor 1 (APAF1) and caspases 1, 2, 8, 9. and 10. An additional group of antiapoptotic genes related to T cell receptor-mediated apoptosis was also found to be overexpressed in acute relapse and included TCR-binding CD3E antigen, antiapoptotic serine threonin kinase (AKT), and NF kappa B-associated genes like reticuloendotheliosis viral oncogene homolog A (RELA) and human T cell leukemia virus type I-binding protein (Tax1BP) known to inhibit tumor necrosis factor (TNF)-induced apoptosis. Our findings demonstrate impaired apoptotic mechanisms in peripheral lymphocytes from RRMS patients during acute relapse. This suggests that the inflammatory process in active disease is targeted by inhibition of proapoptotic and repression of antiapoptotic genes that allow prolonged abnormal immune responses.

Role of the Survivin gene in pathophysiology

Although the roles of survivin in control of cancer cell division and apoptosis as well as targeting survivin for cancer therapeutics have been extensively explored and reviewed, the pathophysiological role of survivin in normal human cells/organs has not been deeply investigated or sufficiently reviewed. Studies in the latter area, however, appear to be important for the identification of different mechanisms of regulation and function of survivin in normal versus abnormal cells and tissues (including cancer), which might ultimately provide the basis for novel approaches for disease treatment with low toxicity. This Review is intended to summarize current observations in the literature related to the physiological and/or pathological roles for survivin in various normal human cells or organs. Our view of potential future research directions for survivin pertinent to potential therapeutic applications will also be discussed.

Increased Spontaneous Ex Vivo Apoptosis and Subset Alterations in Peripheral Blood T Cells from Patients with Multiple Sclerosis

In order to characterize the immunophenotype and the lymphocyte apoptosis in multiple sclerosis (MS) patients, the peripheral blood lymphocytes of 46 MS patients and 12 healthy volunteers were studied by flow cytometry. Immunophenotypic alterations included significant increases in T CD4+ lymphocytes and reductions in the percentages of CD3+ and CD8+ T cells. After 24 h of culture spontaneous apoptosis was increased in almost T lymphocyte subsets from MS patients and it was significantly higher in those patients who had suffered more than two relapses in the two previous years. The incidence of spontaneous apoptosis was not dependent on FasL-Fas interactions and correlated with the percentages of cells positive for active caspases but not with percentages of Fas+ cells. The increased susceptibility to apoptosis of peripheral blood T lymphocytes from MS patients is difficult to reconcile with the previously proposed role of a defective lymphocyte apoptosis in the pathophysiology of MS.

Decreased levels of CD95 and caspase-8 mRNA in multiple sclerosis patients with gadolinium-enhancing lesions on MRI

Magnetic resonance imaging (MRI) allows examining inflammation and central nervous system (CNS) tissue damage in patients suffering from multiple sclerosis (MS), a demyelinating disease of the CNS. Using real-time PCR, we quantified mRNA levels of apoptosis regulators CD95, CD95 ligand, caspase-8, -10 and cellular FLICE-inhibitory protein (cFLIP), and cytokines IL-10 and TNF-alpha in blood mononuclear cells of MS patients at the time of MRI examination. Patients with detectable gadolinium-enhancing lesions had lower expression of CD95 and caspase-8 (P<0.05). Lesion load and brain atrophy did not correlate with expression levels of any of the target molecules studied. Disease duration correlated positively with both FLIP/caspase-8 and CD95/CD3 ratios (P<0.05). These results support the notion that the CD95-dependent pathway plays a complex role in the regulation of survival of activated immune cells in MS.