Evaluation of the association between KIR polymorphisms and systemic sclerosis : a meta-analysis

Background: The results of investigations on the association between killer cell immunoglobulin-like receptor (KIR) gene polymorphisms and the risk of systemic sclerosis (SSc) are inconsistent. To comprehensively evaluate the influence of KIR polymorphisms on the risk of SSc, this meta-analysis was performed. Methods: A systematic literature search was performed in electronic databases including Scopus and PubMed/ MEDLINE to find all available studies involving KIR gene family polymorphisms and SSc risk prior to July 2019. Pooled odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were measured to detect associations between KIR gene family polymorphisms and SSc risk. Results: Five articles, comprising 571 patients and 796 healthy participants, evaluating the KIR gene family polymorphisms were included in the final meta-analysis according to the inclusion and exclusion criteria, and 16 KIR genes were assessed. None of the KIR genes were significantly associated with the risk of SSc. Conclusions: The current meta-analysis provides evidence that KIR genes might not be potential risk factors for SSc risk

Combined effects of CXCL8 and CXCR2 gene polymorphisms on susceptibility to systemic sclerosis

A previous study suggested that the CXCR2 (+1208) TT genotype was associated with increased risk of systemic sclerosis (SSc). In the present study, we investigated the influence of variation in the CXCL8 and CXCR2 genes on susceptibility to SSc and combined the variant alleles of these genes to analyze their effects on SSc. Methods: One fifty one patients with SSc and 147 healthy bone marrow donors were enrolled in a casecontrol study. Blood was collected for DNA extraction; typing of CXCL8 (251) T/A and CXCR2 (+1208) T/ C genes was made by polymerase chain reaction with sequence specific primers (PCR-SSP), followed by agarose gel electrophoresis. Results: The CXCR2-TC genotype was significantly less frequent in patients (23.8% versus 55.1% in controls; P < 0.001, OR = 0.26, 95%CI = 0.15–0.43), whereas the CXCR2-CC genotype was significantly more frequent (44.4% versus 22.4% in controls; P < 0.001, OR = 2.76, 95%CI, 1.62–4.72). When CXCR2 and CXCL8 combinations were analyzed, the presence of CXCR2 T in the absence of CXCL8 A (CXCR2 T+/CXCL8 A) was more frequent in patients than in controls (34.5% versus 3.5%; P < 0.001, OR = 14.50, 95%CI = 5.04– 41.40). However, CXCR2 TT and CXCL8 A were significantly more common in controls (100%) than in patients (58.3%) (P < 0.001). Likewise, the presence of CXCR2 TC and CXCL8 A was more frequent in controls (95.1%) than in patients (75%) (P = 0.004). Furthermore, the CXCR2-CC genotype in CXCL8 A was more frequent in patients (59.7% versus 0% in controls; P < 0.001, adjusted OR = 98.67, 95%CI = 6.04– 1610.8). In patients, a high frequency was observed in combination with the CXCL8 TA and AA genotypes (P < 0.001; OR = 28.92), whereas in controls, there was a high frequency of combination with CXCL8 T (P < 0.001; OR = 0.03) and TT (P < 0.001; OR = 0.01). ). Conclusions: These findings suggest a protective role of CXCL8 (251) A in the CXCR2 (+1208) TT and TC genotypes and an increased risk of CXCL8 (251) A in association with the CXCR2 (+1208) CC genotype in SSc patient

Molecular analysis of pathogens in cerebrospinal fluid by the polymerase chain reaction in HIV-infected patients

Introdução: A reação em cadeia da polimerase (PCR) foi teste de grande impacto no diagnóstico das meningites e encefalites linfocíticas durante a última década. Esse método foi extensivamente usado no diagnóstico das infecções do sistema nervoso central (SNC), devido a sua habilidade em detectar amostras mínimas de DNA-alvo no líquido cefalorraquiano. Objetivo: O objetivo deste estudo foi identificar a prevalência dos patógenos oportunistas responsáveis por causar problemas neurológicos em pacientes infectados com o vírus da imunodeficiência humana (HIV) e avaliar sua associação com os achados clínicos, laboratoriais e da tomografia computadorizada cerebral (TCC). Pacientes e métodos: Um estudo transversal foi realizado em 203 amostras de líquido cefalorraquiano (LCR) de pacientes do sul do Brasil infectados com HIV e com aparente encefalite e meningite linfocíticas. As amostras foram analisadas para os seguintes agentes pelo método da reação em cadeia da polimerase “nested” ou dupla (N-PCR): citomegalovírus, vírus do Epstein-Barr, vírus do herpes simplex tipos 1 e 2, vírus da varicella zoster, vírus do herpes humano tipo 6, vírus JC, Toxoplasma gondii e micobactérias. Resultado: Pelo menos um patógeno foi encontrado em 77 (38%) dos indivíduos. O Epstein-Barr foi o mais prevalente, com 40 casos (19,7%), seguido pelo citomegalovívus, com 12 casos (15%) e pelo vírus JC, em 9 casos (4,4%). Um N-PCR positivo mostrou associação com aumento de proteínas e de celularidade (P=0,001), meningismo (P=0,017) e tomografia computadorizada anormal (P=0,006). Conclusão: O painel de PCR empregado foi efetivo na identificação de infecções neurológicas severas em pacientes HIV positivos.Introduction: Polymerase chain reaction (PCR) has had great impact on the diagnosis of lymphocytic meningitis and encephalitis over the last decade. It has been extensively used in the diagnosis of central nervous system (CNS) infections for its ability to detect small amounts of target DNA in the cerebrospinal fluid (CSF). Objective: The aim of this study was to identify the prevalence of opportunistic pathogens responsible for neurological disorders in patients infected with human immunodeficiency virus (HIV) and to evaluate its association with clinical, laboratory and cerebral computed tomography (CCT) findings. Patients and methods: A cross-sectional study was performed on 203 cerebrospinal fluids (CSF) from HIV-infected patients from Southern Brazil, with apparent lymphocytic meningitis and encephalitis. CSF samples were analyzed with probes for cytomegalovirus, Epstein-Barr virus, herpes simplex virus types 1 and 2, varicella zoster virus, human herpes virus type 6, JC virus, Toxoplasma gondii and mycobacterium in nested polymerase chain reaction (N-PCR). Results: At least one pathogen was found in 77 (38.0%) individuals. Epstein-Barr virus was the most prevalent with 40 cases (19.7%), followed by cytomegalovirus with 12 cases (5.9%) and JC virus with 9 cases (4.4%). Positive NPCR showed association with high spinal fluid protein and cell count (P=0.001), meningism (P=0.017) and abnormal CCT (P=0.006). Conclusion: The PCR panel used was effective in screening several neurological infections in HIV positive patients

Estudo do polimorfismo dos genes KIR na esclerose sistêmica

As células Natural Killer (NK) fazem parte da resposta imune inata, sendo a primeira linha de defesa do organismo contra vírus, bactérias, tumores e microorganismos. Estas células induzem a morte da célula-alvo quando não há o reconhecimento das moléculas de antígenos leucocitários humanos (HLA) de classe I, através de seus receptores, chamados Killer cell Immunoglobulin-like Receptor (KIR). Vários estudos demonstram o envolvimento dos genes KIR na patogênese das doenças auto-imunes. Acredita-se que combinações desses genes possam ser favoráveis para o desenvolvimento da esclerose sistêmica (ES). Portanto, o conhecimento destes genes relacionados às células NK poderiam ser úteis para o entendimento da patogênese da ES. O objetivo deste estudo é investigar o polimorfismo dos genes KIR em um grupo de pacientes com ES, incluindo a forma difusa e limitada da doença. A freqüência do receptor inibidor KIR2DL2 foi significantemente menor nos pacientes comparada com a do grupo controle (28,7% versus 65,2%; P<0,001; OR=0,21; IC95% 0,11–0,38). Quando analisamos a combinação do receptor inibidor 2DL2, com a presença do ativador 2DS2 (KI2DS2+/KIR2DL2-), encontramos uma maior freqüência nos pacientes (26,1% versus 1,7%; P<0,001; OR=19,94; IC95% 4,7–175,1). Por outro lado, a presença de ambos KIR2DL2 e KIR2DS2 foi mais freqüente no grupo controle (26,9% versus 57,3%; P<0,001; OR=0,27; 95%CI 0,1–0,4). Nenhuma diferença estatística no polimorfismo dos genes KIR foi encontrada entre a forma difusa e a forma limitada. A combinação KIR2DS2+/KIR2DL2– parece ser um fator de risco para o desenvolvimento da ES enquanto a alta freqüência do gene inibidor KIR2DL2 no grupo controle parece ter uma função protetora. Estes resultados indicam um potencial papel dos genes KIR na patogênese da ES.Natural killer (NK) cells have an important role in the early responses to viral infections. They kill diverse target cells with decreased or absent expression of major histocompatibility complex (MHC) class I molecules through the Killer Cell Immunoglobulin-Like Receptors (KIR). Many studies have reported association of KIR genes with autoimmune diseases. The objective of this study is to investigate possible associations of KIR polymorphisms with systemic sclerosis (SSc), including the limited (lSSc) and diffuse (dSSc) forms of the disease. The frequency of inhibitory KIR2DL2 was significantly decreased among patients with SSc compared with healthy controls (28.7% versus 65.2; P<0.001, odds ratio [OR] 0.21, 95% confidence interval [95% CI] 0.11–0.38). When activatory and inhibitory KIR genes were analyzed in combination, the concomitant presence of KIR2DS2 and absence of KIR2DL2 (KI2DS2+/KIR2DL2-) phenotype was more frequent in SSc patients than in the control group (26.08% versus 1.75%; P<0.001, OR=19.94, 95%CI [4.78–175.10]). On the other hand, the presence of both KIR2DS2 and KIR2DL2 was more frequent in the control group (26.96% versus 57.39%; P=0.000005, OR=0.27, 95%CI [0.15–0.49]). No significant difference in KIR genes polymorphisms was found between lSSc and dSSc disease subsets. The combination of KIR2DS2+/KIR2DL2– may be a risk factor for development of SSc while the higher frequency of the inhibitory KIR2DL2 gene in the control group suggest to a protective effect. These results indicate a potential role of KIR genes in the SSc pathogenesis

Influência dos polimorfismos genéticos NFKB1, IL-10, CXCR2 E CXCL8 na esclerose sistêmica

A esclerose sistêmica (ES) é uma doença difusa do tecido conjuntivo caracterizada por anormalidades fibróticas, imunológicas e vasculares. O fator nuclear-kB (NF-kB), como um fator de transcrição essencial envolvido na regulação de respostas imunitárias, parece ser um bom candidato para estudos sobre a patogênese de doenças autoimunes, bem como a interleucina-10 (IL-10) e as quimiocinas, CXCL8 e CXCR2. Vários estudos demonstram o envolvimento dos genes CXCR2 e IL-10 na patogênese das doenças autoimunes. Acredita-se que combinações desses genes possam ser favoráveis para o desenvolvimento da ES, podendo seu conhecimento ser benéfico para o entendimento da patogênese da ES. O objetivo deste estudo é investigar o polimorfismo dos genes IL-10, CXCR2, CXCL8 e NFKB1 em um grupo de pacientes com ES, incluindo a forma difusa e limitada da doença. Nossos resultados confirmam a associação do fenótipo de alta produção (GCC + / GCC +) com risco aumentado para ES, mas não encontrou nenhuma correlação com polimorfismos do NF-KB. Nossos achados também sugerem um papel protetor da CXCL8 (- 251) A nos genótipos TT e TC do gene CXCR2 (+1208) e um risco aumentado do CXCL8 (-251) A em associação com o genótipo CC do CXCR2 (+1208) em pacientes com ES. Nenhuma diferença estatística no polimorfismo dos genes IL-10, CXCR2, CXCL8 e NFKB1 foram encontradas entre a forma difusa e a forma limitada. Estes resultados indicam um potencial papel do gene IL-10 e da combinação CXCR2/CXCL8 na patogênese da ES.Systemic sclerosis (SSc) is a connective tissue disease characterized by fibrotic, immunological and vascular abnormalities. Nuclear factor-kB (NF-kB), as a key transcription factor involved in the regulation of immune responses, appears to be a good candidate for studies on the pathogenesis of autoimmune diseases, as well as the interleukin-10 (IL-10) polymorphism, and CXCL8 and CXCR2 chemokines. Several studies have demonstrated the involvement of genes CXCR2 and IL-10 in the pathogenesis of autoimmune diseases. It is believed that combinations of these genes may be favorable for the development of SSc, and this knowledge can contribute to the understanding of the pathogenesis of SSc. The objective of this study is to investigate the polymorphism of IL-10, CXCR2, CXCL8 and NFKB1 in a group of patients with SSc, including diffuse and limited subtypes of the disease. Our results confirm the association of high-producing phenotype (GCC/GCC) with increased risk for SSc, but found no correlation with NFKB1 polymorphisms. Our findings also suggest a protective role of CXCL8 (-251) A in the CXCR2 (+1208) TT and TC genotypes and an increased risk of CXCL8 (-251) A in association with the CXCR2 (+1208) CC genotype in SSc patients. No statistical difference in the polymorphism of IL-10, NFKB1, CXCR2 and CXCL8 were found between the diffuse and limited SSc. These results indicate a potential role of the IL-10 gene and the combination CXCR2/CXCL8 in the pathogenesis of SSc

Influência dos polimorfismos genéticos NFKB1, IL-10, CXCR2 E CXCL8 na esclerose sistêmica

A esclerose sistêmica (ES) é uma doença difusa do tecido conjuntivo caracterizada por anormalidades fibróticas, imunológicas e vasculares. O fator nuclear-kB (NF-kB), como um fator de transcrição essencial envolvido na regulação de respostas imunitárias, parece ser um bom candidato para estudos sobre a patogênese de doenças autoimunes, bem como a interleucina-10 (IL-10) e as quimiocinas, CXCL8 e CXCR2. Vários estudos demonstram o envolvimento dos genes CXCR2 e IL-10 na patogênese das doenças autoimunes. Acredita-se que combinações desses genes possam ser favoráveis para o desenvolvimento da ES, podendo seu conhecimento ser benéfico para o entendimento da patogênese da ES. O objetivo deste estudo é investigar o polimorfismo dos genes IL-10, CXCR2, CXCL8 e NFKB1 em um grupo de pacientes com ES, incluindo a forma difusa e limitada da doença. Nossos resultados confirmam a associação do fenótipo de alta produção (GCC + / GCC +) com risco aumentado para ES, mas não encontrou nenhuma correlação com polimorfismos do NF-KB. Nossos achados também sugerem um papel protetor da CXCL8 (- 251) A nos genótipos TT e TC do gene CXCR2 (+1208) e um risco aumentado do CXCL8 (-251) A em associação com o genótipo CC do CXCR2 (+1208) em pacientes com ES. Nenhuma diferença estatística no polimorfismo dos genes IL-10, CXCR2, CXCL8 e NFKB1 foram encontradas entre a forma difusa e a forma limitada. Estes resultados indicam um potencial papel do gene IL-10 e da combinação CXCR2/CXCL8 na patogênese da ES.Systemic sclerosis (SSc) is a connective tissue disease characterized by fibrotic, immunological and vascular abnormalities. Nuclear factor-kB (NF-kB), as a key transcription factor involved in the regulation of immune responses, appears to be a good candidate for studies on the pathogenesis of autoimmune diseases, as well as the interleukin-10 (IL-10) polymorphism, and CXCL8 and CXCR2 chemokines. Several studies have demonstrated the involvement of genes CXCR2 and IL-10 in the pathogenesis of autoimmune diseases. It is believed that combinations of these genes may be favorable for the development of SSc, and this knowledge can contribute to the understanding of the pathogenesis of SSc. The objective of this study is to investigate the polymorphism of IL-10, CXCR2, CXCL8 and NFKB1 in a group of patients with SSc, including diffuse and limited subtypes of the disease. Our results confirm the association of high-producing phenotype (GCC/GCC) with increased risk for SSc, but found no correlation with NFKB1 polymorphisms. Our findings also suggest a protective role of CXCL8 (-251) A in the CXCR2 (+1208) TT and TC genotypes and an increased risk of CXCL8 (-251) A in association with the CXCR2 (+1208) CC genotype in SSc patients. No statistical difference in the polymorphism of IL-10, NFKB1, CXCR2 and CXCL8 were found between the diffuse and limited SSc. These results indicate a potential role of the IL-10 gene and the combination CXCR2/CXCL8 in the pathogenesis of SSc

Estudo do polimorfismo dos genes KIR na esclerose sistêmica

As células Natural Killer (NK) fazem parte da resposta imune inata, sendo a primeira linha de defesa do organismo contra vírus, bactérias, tumores e microorganismos. Estas células induzem a morte da célula-alvo quando não há o reconhecimento das moléculas de antígenos leucocitários humanos (HLA) de classe I, através de seus receptores, chamados Killer cell Immunoglobulin-like Receptor (KIR). Vários estudos demonstram o envolvimento dos genes KIR na patogênese das doenças auto-imunes. Acredita-se que combinações desses genes possam ser favoráveis para o desenvolvimento da esclerose sistêmica (ES). Portanto, o conhecimento destes genes relacionados às células NK poderiam ser úteis para o entendimento da patogênese da ES. O objetivo deste estudo é investigar o polimorfismo dos genes KIR em um grupo de pacientes com ES, incluindo a forma difusa e limitada da doença. A freqüência do receptor inibidor KIR2DL2 foi significantemente menor nos pacientes comparada com a do grupo controle (28,7% versus 65,2%; P<0,001; OR=0,21; IC95% 0,11–0,38). Quando analisamos a combinação do receptor inibidor 2DL2, com a presença do ativador 2DS2 (KI2DS2+/KIR2DL2-), encontramos uma maior freqüência nos pacientes (26,1% versus 1,7%; P<0,001; OR=19,94; IC95% 4,7–175,1). Por outro lado, a presença de ambos KIR2DL2 e KIR2DS2 foi mais freqüente no grupo controle (26,9% versus 57,3%; P<0,001; OR=0,27; 95%CI 0,1–0,4). Nenhuma diferença estatística no polimorfismo dos genes KIR foi encontrada entre a forma difusa e a forma limitada. A combinação KIR2DS2+/KIR2DL2– parece ser um fator de risco para o desenvolvimento da ES enquanto a alta freqüência do gene inibidor KIR2DL2 no grupo controle parece ter uma função protetora. Estes resultados indicam um potencial papel dos genes KIR na patogênese da ES.Natural killer (NK) cells have an important role in the early responses to viral infections. They kill diverse target cells with decreased or absent expression of major histocompatibility complex (MHC) class I molecules through the Killer Cell Immunoglobulin-Like Receptors (KIR). Many studies have reported association of KIR genes with autoimmune diseases. The objective of this study is to investigate possible associations of KIR polymorphisms with systemic sclerosis (SSc), including the limited (lSSc) and diffuse (dSSc) forms of the disease. The frequency of inhibitory KIR2DL2 was significantly decreased among patients with SSc compared with healthy controls (28.7% versus 65.2; P<0.001, odds ratio [OR] 0.21, 95% confidence interval [95% CI] 0.11–0.38). When activatory and inhibitory KIR genes were analyzed in combination, the concomitant presence of KIR2DS2 and absence of KIR2DL2 (KI2DS2+/KIR2DL2-) phenotype was more frequent in SSc patients than in the control group (26.08% versus 1.75%; P<0.001, OR=19.94, 95%CI [4.78–175.10]). On the other hand, the presence of both KIR2DS2 and KIR2DL2 was more frequent in the control group (26.96% versus 57.39%; P=0.000005, OR=0.27, 95%CI [0.15–0.49]). No significant difference in KIR genes polymorphisms was found between lSSc and dSSc disease subsets. The combination of KIR2DS2+/KIR2DL2– may be a risk factor for development of SSc while the higher frequency of the inhibitory KIR2DL2 gene in the control group suggest to a protective effect. These results indicate a potential role of KIR genes in the SSc pathogenesis

Autoimmune rheumatic diseases and their association with killer immunoglobulin-like receptor genes

Os genes Killer Immunoglobulin-like Receptors (KIR) expressam-se como receptores que estimulam ou inibem as células Natural Killer (NK). As células NK fazem parte da imunidade inata e através de seus receptores KIR identifi cam células-alvo que apresentam moléculas HLA (Human Leukocyte Antigen) modifi cadas ou diferentes, induzindo à sua lise. Os receptores KIR são resultados da expressão dos genes KIR (19q13.14) na membrana celular das células NK, os quais são polimórfi cos e formam haplótipos. A diversidade de frequência dos haplótipos KIR em certas populações sugere que alguns indivíduos apresentam diferentes níveis de proteção contra algumas doenças e o balanço entre inibição e ativação celular mediada pelos receptores KIR e seus ligantes faz com que a célula NK possa auxiliar o organismo na vigilância imunológica. Além disso, há várias evidências da existência de associação de genótipos KIR ativadores com risco aumentado de doença autoimune.Killer Immunoglobulin-like Receptor (KIR) genes express as receptors that activate or inhibit Natural Killer (NK) cells. The NK cells are part of the innate immune response and, through their KIR receptors, they identify target cells that have modifi ed or different HLA (Human Leukocyte Antigen) molecules, inducing their lysis. The KIR receptors result from the expression of KIR genes (19q13.14) on the cell membrane of NK cells, which are polymorphic, and form haplotypes. The diversity of the frequency of KIR haplotypes in certain populations suggests that some individuals have different levels of protection against some diseases. The balance between cell inhibition and activation enables the NK cell to help the organism in immunological surveillance. In addition, there is evidence of the association of activating KIR genotypes with an increased risk for autoimmune disease