RESUMO
BACKGROUND: Killer-cell immunoglobulin-like receptors (KIRs) are a group of regulatory molecules able to activate or inhibit natural killer cells upon interaction with human leukocyte antigen (HLA) class I molecules. Combinations of KIR and HLA may contribute to the occurrence of different immunological and clinical responses to infectious diseases. Leprosy is a chronic neglected disease, both disabling and disfiguring, caused mainly by Mycobacterium leprae. In this case-control study, we examined the influence of KIRs and HLA ligands on the development of multibacillary leprosy. METHODOLOGY/PRINCIPAL FINDINGS: Genotyping of KIR and HLA genes was performed in 264 multibacillary leprosy patients and 518 healthy unrelated controls (238 healthy household contacts and 280 healthy subjects). These are unprecedented results in which KIR2DL2/KIR2DL2/C1/C2 and KIR2DL3/2DL3/C1/C1 indicated a risk for developing lepromatous and borderline leprosy, respectively. Concerning to 3DL2/A3/A11+, our study demonstrated that independent of control group (contacts or healthy subjects), this KIR receptor and its ligand act as a risk factor for the borderline clinical form. CONCLUSIONS/SIGNIFICANCE: Our finding suggests that synergetic associations of activating and inhibitory KIR genes may alter the balance between these receptors and thus interfere in the progression of multibacillary leprosy.
Assuntos
Predisposição Genética para Doença , Antígenos HLA/genética , Hanseníase Multibacilar/genética , Receptores KIR/genética , Adulto , Idoso , Brasil/epidemiologia , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Hanseníase Multibacilar/epidemiologia , Masculino , Pessoa de Meia-Idade , Doenças NegligenciadasRESUMO
The aim of this study was to determine the allele and haplotype frequencies of HLA-A, -B, -DRB1, and -DQB1 in a self-declared White population from the north and northwestern state of Paraná, southern Brazil, and compare the data with populations worldwide. The genotyping was performed with a group of 641 individuals, based on PCR-SSO and -SSP methods, and allele and haplotype frequencies were estimated. Comparisons with European, African, Asian, and Amerindian populations were performed. The most frequent allelic groups, alleles and haplotypes were: HLA-A*02, HLA-B*35, HLA-DRB1*07:01, HLA-DQB1*03:01, and HLA-A*01/B*08/DRB1*03:01. The results reinforced a predominance of a European composition in the self-declared White population from the north and northwestern Paraná.
Assuntos
Genética Populacional , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Cadeias alfa de HLA-DQ/genética , Cadeias beta de HLA-DQ/genética , Cadeias HLA-DRB1/genética , Haplótipos , Adulto , Alelos , Brasil , Feminino , Frequência do Gene , Voluntários Saudáveis , Humanos , Masculino , Polimorfismo GenéticoRESUMO
ABSTRACT INTRODUCTION: Human leukocyte antigens (HLA) are molecules that present antigen to the immune system; their presence or absence have been described as an influential factor in some diseases. HLA-B*27 is an HLA polymorphism that has been associated with increased susceptibility to ankylosing spondylitis (AS) and other spondyloarthropaty. The detection of HLA-B*27 has been used as diagnostic and prognostic tool in these cases, as well as in the differential diagnosis of other diseases. OBJECTIVE: Standardize the single specific primer-polymerase chain reaction (PCR-SSP) methodology for use in the Immunogenetics Laboratory of the Universidade Estadual de Maringá (UEM), considering its specificity and cost-effectiveness. MATERIAL AND METHODS: A total of 30 individuals without AS positive for HLA-B*27 allele and 10 AS negative individuals, were previously tested by PCR-sequence specific oligonucleotide (PCR-SSO) and, in this study, by PCR-SSP. RESULTS: One hundred percent of the patients tested confirmed their results, even with different subtypes. CONCLUSION: Considering the high reproducibility and the broad spectrum of subtypes covering, it was concluded that the PCR-SSP identifying method for HLA-B*27 can be used as a routine diagnostic tool for spondyloarthropathies.
RESUMO INTRODUÇÃO: Os antígenos leucocitários humanos (HLA) são moléculas que apresentam antígenos ao sistema imune; a presença ou a ausência deles é descrita como fator influente em algumas doenças. O HLA-B*27 é um polimorfismo do HLA que tem sido associado à maior predisposição à espondilite anquilosante (EA) e a outras espondiloartropatias. A detecção do HLA-B*27 é utilizada como ferramenta diagnóstica e prognóstica nesses casos, assim como no diagnóstico diferencial de outras doenças. OBJETIVO: Padronizar a metodologia de reação em cadeia da polimerase-iniciador específico (PCR-SSP) para utilização no Laboratório de Imunogenética da Universidade Estadual de Maringá (UEM), considerando sua especificidade e seu custo-benefício. MATERIAL E MÉTODOS: Foram utilizados 30 indivíduos comprovadamente sem EA positivos para o alelo HLA-B*27 e 10 indivíduos negativos, testados previamente por PCR-oligonucleotídeo específico (PCR-SSO) e, neste estudo, por PCR-SSP. RESULTADOS: Cem por cento dos pacientes testados tiveram seus resultados confirmados, mesmo com diferentes subtipos. CONCLUSÃO: Tendo em vista a alta reprodutibilidade e o amplo espectro de subtipos que abrange, concluiu-se que a técnica de identificação de PCR-SSP para o HLA-B*27 pode ser utilizada como auxílio diagnóstico de rotina para espondiloartropatias.
