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1.
Exp Dermatol ; 33(1): e14982, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37994568

ABSTRACT

Regulatory T cells (Tregs) are involved in the suppression of activated T cells in generalized vitiligo (GV). The study was aimed to investigate resident memory (TRM)-Tregs and antigen-specific Tregs' numbers and functional defects in 25 GV patients and 20 controls. CD4+ & CD8+ TRM cell proliferation was assessed by BrDU assay; production of IL-10, TGF-ß, IFN-γ, perforin and granzyme B were assessed by ELISA and enumeration of TRM cells was done by flowcytometry. GV patients showed significantly increased frequency and absolute count of CD4+ & CD8+ TRM cells in lesional (L), perilesional (PL) and non-lesional (NL) skin compared to controls (p = 0.0003, p = 0.0029 & p = 0.0115, respectively & p = 0.0003, p = 0.003 & p = 0.086, respectively). Whereas, TRM-Treg (p < 0.0001 & p = 0.0015) and antigen-specific Tregs (p = 0.0014 & p = 0.003) exhibited significantly decreased frequency and absolute counts in L & PL skin. GV patients showed reduced suppression of CD8+ & CD4+ TRM cells (with increased IFN-γ, perforin & granzyme B) and decreased TRM-Tregs and antigen-specific Tregs (with decreased IL-10 & TGF-ß production) and reduced proliferation of SK-Mel-28 cells in co-culture systems. Immunohistochemistry revealed increased expression of TRM stimulating cytokines: IL-15 & IL-17A and reduced expression of TGF-ß & IL-10 in L, PL, NL skins compared to controls. These results for the first time suggest that decreased and impaired TRM-Tregs and antigen-specific Tregs are unable to suppress CD4+ & CD8+ TRMs' cytotoxic function and their proliferation due to decrease production of immunosuppressive cytokines (IL-10 & TGF-ß) and increased production of TRM based IFN-γ, perforin and granzyme B production, thus compromising the melanocyte survival in GV.


Subject(s)
Vitiligo , Humans , Vitiligo/metabolism , T-Lymphocytes, Regulatory , Granzymes/metabolism , Interleukin-10/metabolism , Perforin/metabolism , Memory T Cells , Melanocytes , Cytokines/metabolism , Transforming Growth Factor beta/metabolism , Antigens , CD8-Positive T-Lymphocytes
2.
Biochem Genet ; 61(3): 823-846, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36258103

ABSTRACT

Rheumatoid Arthritis (RA) is a chronic autoimmune disease characterized by severe joint pain. There are conflicting results for the association of Interleukin 4 (IL4) variable number tandem repeats (VNTR; rs8179190) polymorphism with RA. Therefore, we performed a meta-analysis of the available studies to investigate the association of IL4 VNTR polymorphism with RA risk and severity in the overall populations and Asian, Egyptian, European, and Turkish ethnicities by sub-group analyses. Eight studies involving 1993 RA patients and 1732 controls were included in this meta-analysis. We found increased RA risk for the susceptible "R2R2" genotype and "R2" allele under heterozygous, recessive, and allelic models in the Asian populations (p < 0.00001, p < 0.0001, p = 0.001). We observed a significant association between "R2R2" genotype and "R2" allele for RA protection in the Turkish population under heterozygous, recessive, and allelic models (p = 0.01, p = 0.004, p = 0.002). Disease severity-based analysis revealed significant association for "R2R2" genotype and "R2" allele with RA severity under homozygous, heterozygous, recessive, dominant, and allelic models(p = 0.0004, p = 0.03, p = 0.02, p = 0.003, p = 0.01), specifically in Asian populations (p = 0.009, p = 0.02, p = 0.003, p = 0.03, p = 0.01) and under heterozygous, dominant, and allelic genetic models in Egyptian (p = 0.0001, p < 0.0001, p < 0.0001) and European (p = 0.002, p = 0.0007, p = 0.0006) populations. In silico analysis suggested that the susceptible "R2" allele changes the RNA secondary structure to a stable form by changing minimum free energy(ΔG) from - 115.20 to - 136.40 kcal/mol, which might lead to increased stability of IL-4 in RA patients. Overall, the meta-analysis suggests for the involvement of susceptible "R2" allele with RA risk in the Asian populations, RA severity in the overall populations (specifically in Asian, Egyptian, & European populations), and RA protection in the Turkish population.


Subject(s)
Arthritis, Rheumatoid , Interleukin-4 , Minisatellite Repeats , Polymorphism, Genetic , Humans , Arthritis, Rheumatoid/genetics , Genetic Predisposition to Disease , Genotype , Interleukin-4/genetics
3.
Immunology ; 167(3): 314-327, 2022 11.
Article in English | MEDLINE | ID: mdl-35754117

ABSTRACT

NFATs and FOXP3 are linked with impaired regulatory T-cells (Tregs) in generalized vitiligo (GV). To elucidate calcium mediated NFATc1 signalling pathway and its effect on Treg suppressive capacity in GV. Calcium levels, calcineurin, NFATc1 and GSK-3ß activity and cell proliferation were assessed in 52 GV patients and 50 controls by calcium assay kit, calcineurin phosphatase assay kit, TransAM NFATc1 kit, GSK-3ß ELISA and BrdU cell proliferation assay. Transcripts (CNB, CAM, GSK3B, DYRK1A and calcium channel genes) and protein (IFN-γ, IL-10 and TGF-ß) expressions were assessed by qPCR and ELISA, respectively. Reduced plasma and intracellular Tregs calcium levels and ORAI1 transcripts suggested altered calcium homeostasis in GV Tregs (p = 0.00387, p = 0.0048, p < 0.0001), which led to decreased calcineurin and NFATc1 activity in GV Tregs (p = 0.0299, p < 0.0001). CNB and CAM transcripts were reduced in GV Tregs (p < 0.0001, p = 0.0004). GSK-3ß activity, GSK3B and DYRK1A transcripts significantly increased in GV Tregs (p = 0.0134, p < 0.0001 and p < 0.0001). Plasma (p = 0.0225, p = 0.032) and intracellular Treg (p = 0.0035, p = 0.005) calcium levels, calcineurin (p = 0.001) and NFATc1 (p = 0.001, p < 0.0001) activity and ORAI1 (p = 0.0093, p < 0.0001), CAM and CNB (p = 0.0214) transcripts significantly decreased in active vitiligo (AV) and severe GV (sGV) Tregs. Calcium treatment significantly increased intracellular calcium and ORAI1 transcripts in GV Tregs (p = 0.0042, p = 0.0035). Moreover, calcium treatment enhanced calcineurin and NFATc1 activity in GV Tregs (p = 0.0128, p < 0.0001). Remarkably, calcium treatment increased Treg mediated suppression of CD4+ and CD8+ T-cells (p = 0.015, p = 0.006) in GV and increased Tregs associated cytokines: IL-10 (p = 0.0323, p = 0.009), TGF-ß (p = 0.0321, p = 0.01) and decreased IFN-γ production (p = 0.001, p = 0.016) by CD4+ and CD8+ T-cells. Intracellular calcium levels positively correlated with calcineurin (r = 0.83; p < 0.0001) and NFATc1 (r = 0.61; p < 0.0001) activity, suggesting the enhanced Treg immunosuppressive capacity after calcium treatment. Our study for the first time suggests that reduced plasma calcium and ORAI1 transcripts are linked to calcium uptake defects in Tregs, which leads to reduced calcineurin and NFATc1 activation, thereby contributing to decreased Tregs immunosuppressive capacity in GV. Elevated GSK-3ß activity and GSKB and DYRK1A transcripts are involved in reduced NFATc1 activity in GV Tregs. Overall, the study suggests that calcium-NFATc1-signalling pathway is likely to be involved in defective Tregs function and can be implicated for development of effective Treg mediated therapeutics for GV.


Subject(s)
NFATC Transcription Factors , T-Lymphocytes, Regulatory , Vitiligo , Bromodeoxyuridine/metabolism , CD8-Positive T-Lymphocytes/metabolism , Calcineurin/metabolism , Calcium/metabolism , Calcium Channels/metabolism , Forkhead Transcription Factors/metabolism , Glycogen Synthase Kinase 3 beta/genetics , Glycogen Synthase Kinase 3 beta/metabolism , Humans , Interleukin-10/metabolism , NFATC Transcription Factors/genetics , NFATC Transcription Factors/metabolism , T-Lymphocytes, Regulatory/metabolism , Transforming Growth Factor beta/metabolism , Vitiligo/metabolism
4.
Adv Exp Med Biol ; 1367: 61-103, 2022.
Article in English | MEDLINE | ID: mdl-35286692

ABSTRACT

Vitiligo is a hypomelanotic skin disease and considered to be of autoimmune origin due to breaching of immunological self-tolerance, resulting in inappropriate immune responses against melanocytes. The development of vitiligo includes a strong heritable component. Different strategies ranging from linkage studies to genome-wide association studies are used to explore the genetic factors responsible for the disease. Several vitiligo loci containing the respective genes have been identified which contribute to vitiligo and genetic variants for some of the genes are still unknown. These genes include mainly the proteins that play a role in immune regulation and a few other genes important for apoptosis and regulation of melanocyte functions. Despite the available data on genetic variants and risk alleles which influence the biological processes, only few immunological pathways have been found responsible for all ranges of severity and clinical manifestations of vitiligo. However, studies have concluded that vitiligo is of autoimmune origin and manifests due to complex interactions in immune components and their inappropriate response toward melanocytes. The genes involved in the immune regulation and processing the melanocytes antigen and its presentation can serve as effective immune-therapeutics that can target specific immunological pathways involved in vitiligo. This chapter highlights those immune-regulatory genes involved in vitiligo susceptibility and loci identified to date and their implications in vitiligo pathogenesis.


Subject(s)
Vitiligo , Genetic Linkage , Genome-Wide Association Study , Humans , Immunogenetics , Melanocytes/pathology , Vitiligo/genetics
5.
Cytokine ; 140: 155432, 2021 04.
Article in English | MEDLINE | ID: mdl-33517195

ABSTRACT

Tumor necrosis factor-α (TNF-α) is a major mediator of inflammation and its increased levels have been analyzed in vitiligo patients. Vitiligo is a depigmentary skin disarray caused due to disapperance of functional melanocytes. The aim of the study was to investigate the role of TNF-α in melanocyte biology, analyzing candidate molecules of melanocytes and immune homeostasis. Our results showed increased TNF-α transcripts in vitiligenous lesional and non-lesional skin. Melanocytes upon exogenous stimulation with TNF-α exhibited a significant reduction in cell viability with elevated cellular and mitochondrial ROS and compromised complex I activity. Moreover, we observed a reduction in melanin content via shedding of dendrites, down-regulation of MITF-M, TYR and up-regulation of TNFR1, IL6, ICAM1 expression, whereas TNFR2 levels remain unaltered. TNF-α exposure stimulated cell apoptosis at 48 h and autophagy at 12 h, elevating ATG12 and BECN1 transcripts. Our novel findings establish the functional link between autophagy and melanocyte destruction. Overall, our study suggests a key function of TNF-α in melanocyte homeostasis and autoimmune vitiligo pathogenesis.


Subject(s)
Melanins/metabolism , Melanocytes/metabolism , Signal Transduction/physiology , Tumor Necrosis Factor-alpha/metabolism , Vitiligo/metabolism , Apoptosis/physiology , Autophagy-Related Protein 12/metabolism , Beclin-1/metabolism , Down-Regulation/physiology , Humans , Intercellular Adhesion Molecule-1/metabolism , Interleukin-6/metabolism , Receptors, Tumor Necrosis Factor, Type I/metabolism , Receptors, Tumor Necrosis Factor, Type II/metabolism , Skin/metabolism , Up-Regulation/physiology
6.
Exp Dermatol ; 29(8): 759-775, 2020 08.
Article in English | MEDLINE | ID: mdl-32682346

ABSTRACT

Regulatory T cells (Tregs) are involved in the suppression of activated T cells in generalized vitiligo (GV). The study was aimed to investigate Tregs functional defects in Treg:CD8+ and Treg:CD4+ T cells' co-culture systems of 55 GV patients and 45 controls. CD8+ and CD4+ T-cell proliferation was assessed by BrdU assay; production of IL-10, TGF-ß and IFN-γ cytokines was assessed by ELISA; and FOXP3, CD25, NFATC1 and CD44 proteins were measured by flow cytometry. Generalized vitiligo patients showed reduced suppression of CD8+ and CD4+ T cells (P = .0384, P = .0084), increased IFN-γ (P < .0001, P = .0019), decreased IL-10 and TGF-ß (P < .0001) and decreased FOXP3, CD25 and NFATC1 proteins (P < .0001). Active vitiligo (AV) patients showed reduced suppression of CD8+ & CD4+ T cells (P = .006, P = .015), increased IFN-γ (P = .036, P = .045), decreased IL-10 (P = .009, P = .021), FOXP3 (P = .0244) and NFATC1 (P = .019). Severe GV (50%-75% VASI) patients showed reduced suppression of CD8+ and CD4+ T cells (P = .0003, P = .001), increased IFN-γ (P = .0029, P < .0001), decreased IL-10 (P = .0057, P = .0017), FOXP3 (P = .002) and NFATC1 (P = .0347). VASI score was positively correlated with the suppression of CD8+ and CD4+ T cells (P = .0006, P < .0001), IL-10 (P = .0096, P = .029), FOXP3 (P = .0008) and NFATC1 (P = .043), whereas it was negatively correlated with IFN-γ (P = .0029, P = .0017). Early age of onset patients' Tregs demonstrated decreased suppression of CD8+ and CD4+ T cells (P = .0156, P = .0074), decreased TGF-ß (P = .0212, P = .0083) and NFATC1 (P = .0103). NFATC1 was positively correlated with FOXP3 in Tregs (P < .0001). Our results suggest impaired Tregs suppressive function in GV patients due to decreased NFATC1, FOXP3, CD25, IL-10 and TGF-ß resulting into increased CD8+ and CD4+ T-cell proliferation and IFN-γ production. For the first time, decreased NFATC1 levels were correlated with decreased FOXP3, thereby altering Treg cell function in GV patients. Additionally, decreased Treg cell function also affected onset, activity and severity of GV.


Subject(s)
Cytokines/metabolism , Forkhead Transcription Factors/metabolism , NFATC Transcription Factors/metabolism , T-Lymphocytes, Regulatory/immunology , Vitiligo/immunology , Vitiligo/metabolism , Adolescent , Adult , Age of Onset , CD4-Positive T-Lymphocytes/physiology , CD8-Positive T-Lymphocytes/physiology , Case-Control Studies , Cell Proliferation , Cells, Cultured , Child , Coculture Techniques , Female , Humans , Interferon-gamma/metabolism , Interleukin-10/metabolism , Interleukin-2 Receptor alpha Subunit/metabolism , Male , Middle Aged , Severity of Illness Index , Transforming Growth Factor beta/metabolism , Young Adult
7.
Ann Hematol ; 99(5): 925-935, 2020 May.
Article in English | MEDLINE | ID: mdl-32157419

ABSTRACT

Sickle cell disease (SCD) is an autosomal recessive blood disorder which occurs due to point mutation in the ß-globin chain of hemoglobin. Since the past decades, various therapies have been put forth, which are based on obstructing pathophysiological mechanisms of SCD including inhibition of Gardos channel and cation fluxes which in turn prevents sickle erythrocyte destruction and dehydration. The pharmacological approaches are based on the mechanism of reactivating γ-globin expression by utilizing fetal hemoglobin (HbF)-inducing drugs such as hydroxyurea. In SCD, gene therapy could be considered as a promising tool which involves modifying mutation at the gene-specific target by either promoting insertion or deletion of globins. Although there are various therapies emerged so far in the treatment of SCD, many of them have faced a major setback in most of developing countries in terms of cost, unavailability of expertise, and suitable donor. Therefore, in addition to pathophysiological aspects, this review will discuss new advancements and approaches made in the therapeutic domain of SCD including a viewpoint of modulating hemoglobin in SCD by the intervention of probiotics.


Subject(s)
Anemia, Sickle Cell , Erythrocytes, Abnormal , Fetal Hemoglobin , Hydroxyurea/therapeutic use , Intermediate-Conductance Calcium-Activated Potassium Channels , Probiotics/therapeutic use , Anemia, Sickle Cell/drug therapy , Anemia, Sickle Cell/genetics , Anemia, Sickle Cell/metabolism , Anemia, Sickle Cell/physiopathology , Erythrocytes, Abnormal/metabolism , Erythrocytes, Abnormal/pathology , Fetal Hemoglobin/genetics , Fetal Hemoglobin/metabolism , Humans , Intermediate-Conductance Calcium-Activated Potassium Channels/genetics , Intermediate-Conductance Calcium-Activated Potassium Channels/metabolism
8.
Semin Cell Dev Biol ; 63: 167-179, 2017 03.
Article in English | MEDLINE | ID: mdl-27476447

ABSTRACT

Gene regulation mediates the processes of cellular development and differentiation leading to the origin of different cell types each having their own signature gene expression profile. However, the compact chromatin structure and the timely recruitment of molecules involved in various signaling pathways are of prime importance for temporal and spatial gene regulation that eventually contribute towards cell type and specificity. Poly (ADP-ribose) polymerase-1 (PARP-1), a 116-kDa nuclear multitasking protein is involved in modulation of chromatin condensation leading to altered gene expression. In response to activation signals, it adds ADP-ribose units to various target proteins including itself, thus regulating various key cellular processes like DNA repair, cell death, transcription, mRNA splicing etc. This review provides insights into the role of PARP-1 in gene regulation, cell differentiation and multicellular morphogenesis. In addition, the review also explores involvement of PARP-1 in immune cells development and therapeutic possibilities to treat various human diseases.


Subject(s)
Cell Differentiation/genetics , Poly(ADP-ribose) Polymerases/metabolism , Transcription, Genetic , Animals , Embryonic Development/genetics , Gene Expression Regulation , Humans , Models, Biological
9.
Exp Dermatol ; 23(5): 352-3, 2014 May.
Article in English | MEDLINE | ID: mdl-24628992

ABSTRACT

Vitiligo is an acquired depigmentation disorder characterized by the loss of functional melanocytes from the epidermis. Two major theories of vitiligo pathogenesis include autoimmunity and oxidative stress-mediated toxicity in melanocytes. The present study aimed to evaluate both the hypotheses in vitiligo patients and to investigate their role in the disease onset and progression. Antimelanocyte antibody levels and lipid peroxidation (LPO) levels were evaluated in 427 patients and 440 controls; antithyroid peroxidase (TPO) antibody levels were estimated in 102 patients and 72 controls. Patients showed a significant increase in LPO and antimelanocyte antibody levels compared to controls. Antimelanocyte antibody and LPO levels were higher in active vitiligo compared to stable. Only 9.8% of patients showed the presence of anti-TPO antibodies in their circulation. Oxidative stress may be the initial triggering event to precipitate vitiligo in Gujarat population, which is exacerbated by contributing autoimmune factors together with oxidative stress.


Subject(s)
Autoimmunity/immunology , Iodide Peroxidase/chemistry , Lipid Peroxidation , Melanocytes/cytology , Oxidative Stress , Vitiligo/immunology , Adolescent , Adult , Case-Control Studies , Disease Progression , Female , Humans , India , Iodide Peroxidase/immunology , Male , Melanocytes/immunology , Vitiligo/ethnology , Vitiligo/pathology , Young Adult
10.
Hum Immunol ; : 110812, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38755031

ABSTRACT

Generalized vitiligo(GV) is a skin depigmenting condition due to loss of melanocytes. Regulatory T cells(Tregs), responsible for peripheral tolerance, show altered numbers and functions in GV patients, likely influenced by the aging process. Therefore, the present study was focused on measuring the relative telomere length of Tregs in 96 GV patients and 90 controls by qPCR, along with correlation of relative telomere length with in vitro Treg suppressive capacity. Interestingly, we found significantly decreased relative telomere length in Tregs of GV patients as compared to controls(p = 0.0001). Additionally, age based-analysis suggested significant decrease in relative telomere length in elderly GV patients(>40 years) in comparison to young GV patients(0-20 years; p = 0.0027). Furthermore, age of onset analysis suggested for reduced relative telomere length in early onset GV patients (0-20 years) in comparison to late onset GV patients(>40 years; p = 0.0036). The correlation analysis suggested positive correlation for relative telomere length with in vitro Tregs suppressive capacity(r = 0.68 & r = 0.45; p < 0.0001). Additionally, the in vitro Tregs suppressive capacity was significantly reduced in elderly GV patients(p = 0.003) and early onset GV patients(p = 0.0074). Overall, our study for the first time demonstrated that, the Tregs ageing due to telomere shortening may be responsible for altered Treg functions and number.

11.
Autoimmun Rev ; 23(4): 103515, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38185189

ABSTRACT

Vitiligo is a chronic skin condition marked by the gradual loss of pigmentation, leading to the emergence of white or depigmented patches on the skin. The exact cause of vitiligo remains not entirely understood, although it is thought to involve a blend of genetic, autoimmune, and environmental factors. While there is currently no definitive cure for vitiligo, diverse treatments exist that may assist in managing the condition and fostering repigmentation in specific instances. Animal models play a pivotal role in comprehending the intricate mechanisms that underlie vitiligo, providing valuable insights into the progression and onset of the disease, as well as potential therapeutic interventions. Although induced experimental models lack the nuanced characteristics observed in natural experimental models, relying solely on a single animal model might not fully capture the intricate pathogenesis of vitiligo. Different animal models simulate specific aspects of human vitiligo pathogenesis to varying degrees. This review extensively explores the array of animal models utilized in vitiligo research, shedding light on their respective advantages, disadvantages, and applications.


Subject(s)
Disease Models, Animal , Vitiligo , Vitiligo/etiology , Vitiligo/immunology , Animals , Humans , Mice
12.
Hum Immunol ; 85(1): 110737, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38057201

ABSTRACT

Generalized vitiligo (GV) is characterized by white patches due to autoimmune loss of melanocytes. Regulatory T cells (Tregs) maintain immune homeostasis, while NK cells eliminate pathogens and tumors. Increased NK cell frequency and reduced Treg frequency and suppressive capacity are observed in vitiligo patients. However, studies assessing Treg-mediated suppression of NK cell functions in GV are lacking. Therefore, our study aimed to assess in vitro Treg-mediated suppression of NK cells function over K562 and SK-Mel-28 cells in 31 GV patients and 30 controls using the BrdU-cell proliferation assay. We found decreased Treg-mediated suppression of NK cell function in GV patients (p = 0.0289). Moreover, increased NK cell-mediated K562 and SK-Mel-28 cells' suppression was observed in GV patients (p = 0.0207,p = 0.0419). Disease activity-based analysis, suggested reduced Treg-mediated suppression of NK cell function and increased NK cell function in active vitiligo patients (p = 0.03,p = 0.0436). Interestingly, age-based analysis suggested decreased Treg-mediated suppression of NK cell function in 1-20 and 21-40 years age groups compared to 41-60 years age group of GV patients (p = 0.005,p = 0.0380). Overall, our study, for the first time, suggests that decreased Treg-mediated suppression of NK cells may lead to increased destruction of melanocytes in GV, and this knowledge may help in developing effective therapeutics based on Tregs and NK cells for GV.


Subject(s)
T-Lymphocytes, Regulatory , Vitiligo , Humans , Killer Cells, Natural , Melanocytes
13.
Article in English | MEDLINE | ID: mdl-38240306

ABSTRACT

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), while generalized vitiligo(GV) is an autoimmune disease that causes the loss of functional melanocytes, resulting in white patches all over the body. Human Leukocyte Antigen (HLA) plays a crucial role in immune response to pathogens. Studies assessing the link between GV and COVID-19 are lacking; therefore, our current study was aimed to establish the association between GV and HLAB27 by genotyping the HLAB27 allele in 150 GV patients and 150 controls from South Gujarat population through polymerase chain reaction-sequence-specific primers (PCR-SSP) method. Additionally, we assessed the correlation of GV with COVID-19 and the influence of HLAB27 on COVID-19 development. Interestingly, our study suggested that the HLAB27 allele was prevalent in GV patients as compared to controls (52% vs 35.33%; p = 0.0051). Moreover, the occurrence of COVID-19 was significantly lower in GV patients than in controls (10% vs 32.66%; p < 0.0001). Disease activity-based analysis suggested that COVID-19 occurrence was significantly lower in active vitiligo (AV) patients as compared to stable vitiligo (SV) patients(6.87% vs 31.57%; p = 0.0045). Furthermore, COVID-19 development was significantly reduced in HLAB27 positive individuals as compared to HLAB27 negative individuals (p = 0.0025). Overall, our study suggests, for the first time, that HLAB27 allele might be a genetic risk factor for GV susceptibility, and an ongoing immune response in GV patients, more specifically in AV patients, might protect against COVID-19 infection in South Gujarat population. Additionally, our study highlighted the likely role of HLAB27 in protection against COVID-19 development.

14.
Exp Dermatol ; 22(4): 245-50, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23425123

ABSTRACT

Vitiligo is a multifactorial polygenic disorder with a complex pathogenesis, linked with both genetic and non-genetic factors. The precise modus operandi for vitiligo pathogenesis has remained elusive. Theories regarding loss of melanocytes are based on autoimmune, cytotoxic, oxidant-antioxidant and neural mechanisms. Reactive oxygen species (ROS) in excess have been documented in active vitiligo skin. Numerous proteins in addition to tyrosinase are affected. It is possible that oxidative stress is one among the main principal causes of vitiligo. However, there also exists ample evidence for altered immunological processes in vitiligo, particularly in chronic and progressive conditions. Both innate and adaptive arms of the immune system appear to be involved as a primary event or as a secondary promotive consequence. There is speculation on the interplay, if any, between ROS and the immune system in the pathogenesis of vitiligo. The article focuses on the scientific evidences linking oxidative stress and immune system to vitiligo pathogenesis giving credence to a convergent terminal pathway of oxidative stress-autoimmunity-mediated melanocyte loss.


Subject(s)
Oxidative Stress/immunology , Vitiligo/etiology , Apoptosis/immunology , Autoimmunity , Cytokines/metabolism , Genetic Predisposition to Disease , Humans , Melanocytes/immunology , Melanocytes/metabolism , Melanocytes/pathology , Models, Biological , Vitiligo/immunology , Vitiligo/metabolism
15.
Gene ; 880: 147629, 2023 Sep 05.
Article in English | MEDLINE | ID: mdl-37429370

ABSTRACT

Generalized vitiligo (GV) is an autoimmune skin depigmenting disease characterized by loss of functional melanocytes. Nuclear factor of activated T cells (NFATs) play a key role in regulatory T cells' (Tregs) activation and function. Our previous studies have highlighted the role of reduced NFATs expression and activity in impaired Tregs suppressive capacity, leading to GV pathogenesis. 3'UTR region and structural single nucleotide polymorphisms(SNPs) could lead to reduced NFAT expression and activity. Therefore, we studied the association of NFATs 3'UTR [NFATC2 rs4811198 (T > G) & NFATC4 rs11848279 (A > G)] and structural [NFATC1 rs754093 (T > G) & NFATC2 rs12479626 (T > C)] SNPs in 427 GV patients and 415 controls from Gujarat population by Polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP). Additionally, we carried out genotype-phenotype correlation and in silico analysis to assess the effect of NFATs SNPs on NFATs expression and structure. NFATC2 rs4811198 (T > G) 3' UTR & NFATC2 rs12479626 (T > C) structural SNPs were significantly associated with GV (p < 0.0001). Interestingly, for NFATC2 rs4811198 (T > G) SNP, there was a significant difference in the TT vs GG genotypes' frequencies (p = 0.0034; Table 2), and for NFATC2 rs12479626 (T > C) SNP there was a significant difference between TT vs TC and CC genotypes' frequencies (p < 0.0001 & p = 0.0002) between GV patients and controls. Furthermore, Odds ratio suggested that the susceptible alleles for NFATC2 rs4811198 (T > G) & NFATC2 rs12479626 (T > C) SNPs increased the risk of GV by 1.38 & 3.04 fold. However, the NFAT 3' UTR [NFATC2 rs4811198 (T > G)] and structural [NFATC1 rs754093 (T > G)] SNPs were not significantly associated with GV. Interestingly, the genotype-phenotype correlation suggested that the susceptible 'G' allele of NFATC2 rs4811198 (T > G) & NFATC4 rs11848279 (A > G) 3' UTR SNPs lead to reduced NFATC2 and NFATC4 expression (p < 0.0001). Furthermore, in silico analysis suggested that hsa-miR-3183 & hsa-miR-6720-3p miRNAs specifically bound to 'G' allele of NFATC2 rs4811198 SNP and has-miR-4652-3p miRNA specifically bound to 'G' allele of NFATC4 rs11848279 SNP. Overall, our study suggests that NFATC2 rs4811198 (T > G) 3' UTR & NFATC2 rs12479626 (T > C) structural SNPs may be associated with GV susceptibility in Gujarat population. Moreover, the susceptible alleles for the 3' UTR SNPs could lead to reduced NFATs levels, which may further possibly, affect the Treg suppressive function leading to GV.


Subject(s)
MicroRNAs , Vitiligo , Humans , 3' Untranslated Regions/genetics , Vitiligo/genetics , Genetic Predisposition to Disease , Case-Control Studies , Genotype , Polymorphism, Single Nucleotide , MicroRNAs/genetics , NFATC Transcription Factors/genetics , T-Lymphocytes
16.
Int Immunopharmacol ; 125(Pt B): 111174, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37951194

ABSTRACT

BACKGROUND: Generalized vitiligo (GV) is an autoimmune disease characterized by the progressive loss of melanocytes. OBJECTIVES: Current study was undertaken to assess in-vitro therapeutic potential of Harmine and Kaempferol for GV. METHODS: Calcium, calcineurin, NFATC1 levels, cell proliferation were assessed by various kits and ORAI1, PEIZO1, Calcineurin, GSK3B, DYRK1A transcripts and IFN-γ,IL-10,TGF-ß protein levels were assessed by qPCR and ELISA in blood and skin biopsy samples from Tregs of 52 patients and 50 controls. RESULTS: Harmine and Kaempferol treatment enhances Treg suppressive capacity, NFATs and FOXP3 expression in blood and skin Tregs of GV patients (p < 0.05). Furthermore, Harmine and Kaempferol treatment in Tregs increased calcineurin and NFATC1 activity and decreased DYRK1A transcripts in blood and skin Tregs of GV patients(p < 0.05). In-silico analysis revealed that Harmine and Kaempferol might boost Treg suppressive capacity by increasing calcineurin dephosphorylation activity leading to increase NFATs activation and also increase nuclear retention of NFATs by inhibiting DYRK1a phosphorylation activity. Moreover, calcineurin and NFATC1 activity in Tregs were positively correlated with Treg suppressive capacity, NFATC1 and FOXP3 expression (p < 0.05), whereas, DYRK1A transcripts were negatively correlated with Treg suppressive capacity, NFATC1 and FOXP3 expression (p < 0.05). These compounds significantly increased melanocytes' survival and proliferation in Treg:CD4+/CD8+:SK-Mel-28 cell line co-culture system from GV patients (p < 0.0001). CONCLUSIONS: For the first time the study suggests that Harmine and Kaempferol treated Tregs could control the CD8+ and CD4+T-cells' proliferation and IFN-γ production, leading to melanocytes' survival and proliferation. These compounds may serve as novel Treg-based therapeutics for GV; however, in vivo studies are warranted to assess the safety and efficacy of these compounds.


Subject(s)
Vitiligo , Humans , Vitiligo/drug therapy , Harmine/pharmacology , Harmine/therapeutic use , T-Lymphocytes, Regulatory , Calcineurin , Kaempferols/pharmacology , Kaempferols/therapeutic use , Forkhead Transcription Factors/genetics , NFATC Transcription Factors/genetics
17.
Article in English | MEDLINE | ID: mdl-22474495

ABSTRACT

Agents which can either trigger proliferation of ß-cells or induce neogenesis of ß-cells from precursors would be of pivotal role in reversing diabetic manifestations. We examined the role of flavonoid rich fraction (FRF) of Oreocnide integrifolia leaves using a mice model of experimental regeneration. BALB/c mice were subjected to ~70% pancreatectomy (Px) and supplemented with FRF for 7, 14, and 21 days after pancreatectomy. Px animals displayed increased blood glucose levels and decreased insulin titres which were ameliorated by FRF supplementation. FRF-treated mice demonstrated prominent newly formed islets budding off from ducts and depicting increased BrdU incorporation. Additionally, transcripts levels of Ins1/2, Reg-3α/γ, Ngn-3, and Pdx-1 were upregulated during the initial 1 week. The present study provides evidence of a nutraceutical contributing to islet neogenesis from ductal cells as the mode of ß-cell regeneration and a potential therapeutic for clinical trials in management of diabetic manifestations.

18.
Crit Rev Ther Drug Carrier Syst ; 39(2): 97-120, 2022.
Article in English | MEDLINE | ID: mdl-35378015

ABSTRACT

Probiotics colonize in the gastrointestinal tract and regulate the homeostasis in healthy human hosts. These protect the host against putrefactive organisms and secrete soluble factors exhibiting important transductive roles. However, constitutive processes in human host are deregulated following dysbiosis caused during prolonged exposure to cytotoxic agents and pollutants. Apart from restoring the homeostasis, probiotic administration has shown to minimize carcinogenesis and post-surgery complications in cancer patients. Moreover, ability of microbial cells to colonize at tumor foci can be harnessed to deliver genes, therapeutic proteins and antibodies in a selective manner. In this review, we have discussed immunomodulatory roles of probiotics in context to cancer prevention. The article further proposes the use of dietary interventions for boosting anticancer immunity and as an alternative to detrimental chemotherapeutic agents. After summarizing clinical evidences on probiotic efficacy, formulation approaches have been described for effective delivery of the microorganisms. The literature shows that polysaccharide matrices can be employed to achieve the survivability of probiotics. Formulation approaches have been reviewed together with the risks associated with the migration of live microorganisms to systemic circulation and their ability of transmitting antibiotic resistance factors into human pathogens.


Subject(s)
Probiotics , Dysbiosis , Gastrointestinal Tract , Humans , Immunity , Immunomodulation , Probiotics/therapeutic use
19.
Gene ; 809: 146027, 2022 Jan 30.
Article in English | MEDLINE | ID: mdl-34673212

ABSTRACT

Vitiligo is an autoimmune progressive skin depigmenting disease. Tumor necrosis factor alpha (TNF-α) is a pro-inflammatory cytokine and plays a crucial role in vitiligo development. Since there are conflicting results and consensus is lacking for the association of the TNFA gene -308 G > A polymorphism with vitiligo susceptibility; we performed a meta-analysis of all the available studies to investigate the association of TNFA -308 G > A polymorphism with vitiligo risk. 11 studies involving 2199 vitiligo patients and 3083 controls were included in the meta-analysis. The meta-analysis revealed an increased vitiligo risk with "AA", "GA" and "AA" + "GA" genotypes and 'A' allele in the overall (p = 0.006, p = 0.003, p = 0.001 & p = 0.003) and Egyptian populations (p = 0.001, p < 0.00001, p < 0.00001 & p = 0.002). Moreover, we found association for "GA" and "AA" + "GA" genotypes in Asian population (p = 0.0009 & p = 0.005) and for 'A' allele in Asian and middle eastern populations (p = 0.04 & p = 0.0002). Interestingly the disease activity based analysis revealed significant association for "GA", "AA" + "GA" genotypes and 'A' allele with active vitiligo patients in the North American population (p = 0.02). Moreover, we found significant association for "GA", "AA" + "GA" genotypes and 'A' allele with localized vitiligo in overall (p = 0.02, p = 0.02 & p = 0.04) and Asian (p = 0.004, p = 0.003 & p = 0.01) populations. Overall, our meta-analysis suggests the involvement of susceptible 'A' allele with: i) vitiligo susceptibility in overall population and specifically with Asian, Middle Eastern and Egyptian populations; ii) vitiligo disease activity in North American population and iii) localized vitiligo in overall population and specifically in Asian population.


Subject(s)
Polymorphism, Single Nucleotide , Tumor Necrosis Factor-alpha/genetics , Vitiligo/genetics , Female , Genetic Predisposition to Disease , Humans , Male , Medical History Taking
20.
J Immunol Res ; 2022: 3426717, 2022.
Article in English | MEDLINE | ID: mdl-36157881

ABSTRACT

Generalized vitiligo (GV) is an autoimmune skin disease characterized by bilateral white patches over the entire body. Regulatory T cells (Tregs) maintain peripheral tolerance; however, they are found to be reduced in numbers and function in vitiligo patients. The exact mechanism for reduced Treg suppressive capacity is unknown. Therefore, we aimed to assess transcript levels of Tregs-associated immunosuppressive genes (GZMB, NRP1, PDCD1, FASLG, and TNFRS18), regulatory molecules of Tregs suppressive function (SERPINB9, ITPR1, and UBASH3A), and Treg-associated transcription factors (GATA2, GATA3, RUNX1, STAT3, and STAT5) in 52 GV patients and 48 controls by real-time PCR (qPCR). We found significantly reduced GZMB, NRP1, SERPINB9, and ITPR1 transcripts in GV Tregs compared to controls (p = 0.03, p = 0.023, p = 0.0045, and p < 0.0001, respectively). There were 0.44-, 0.45-, 0.32-, and 0.54-fold decrease in GZMB, NRP1, SERPINB9, and ITPR1 transcripts in GV Tregs. Additionally, disease activity and severity-based analyses revealed significantly decreased GZMB (p = 0.019 and 0.034), SERPINB9 (p = 0.031 and p = 0.035), and ITPR1 (p = 0.0003 and p = 0.034) transcripts in active vitiligo and severe GV patients' Tregs. Interestingly, we found a positive correlation for ITPR1 with GZMB (r = 0.45, p = 0.0009) and SERPINB9 (r = 0.52, p = 0.001) transcripts in GV Tregs. Moreover, we found positive correlation for percentage Treg mediated suppression of CD4+ and CD8+T cells with ITPR1 (r = 0.54; r = 0.49), GZMB (r = 0.61; r = 0.58), NRP1 (r = 0.55; r = 0.52), and SERPINB9 (r = 0.56; r = 0.48) in GV Tregs. Further, calcium treatment of Tregs resulted into significantly increased ITPR1, SERPINB9, and GZMB transcripts in GV Tregs (p = 0.023, p = 0.0345, p = 0.02). Overall, our results for the first time revealed the crucial role of GZMB, NRP1, SERPINB9, and ITPR1 transcripts in decreased Treg suppressive capacity leading to GV pathogenesis, progression, and severity. In addition, our study highlighted that ITPR1 might be linked with decreased GZMB and NRP1 expression in GV Tregs. Moreover, our study for the first time suggest that increased SERPINB9 transcripts may lead to endogenous granzyme B-mediated Tregs apoptosis, and calcium treatment of Tregs may improve the Treg suppressive capacity. These findings may further aid in development of Treg-based therapeutics for GV.


Subject(s)
Serpins , Vitiligo , Calcium/metabolism , Core Binding Factor Alpha 2 Subunit/metabolism , Granzymes/metabolism , Humans , Inositol 1,4,5-Trisphosphate Receptors/metabolism , Neuropilin-1 , STAT5 Transcription Factor/metabolism , Serpins/genetics , Serpins/metabolism , T-Lymphocytes, Regulatory , Vitiligo/genetics , Vitiligo/metabolism
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