SABIIA - Sistema Aberto e Integrado de Informação em Agricultura (Sabiia)

Louzada-Júnior,P.; Freitas,M.V.C.; Oliveira,R.D.R.; Deghaide,N.H.S.; Conde,R.A.; Bertolo,M.B.; Donadi,E.A..

The objective of the present study was to evaluate the contribution of the shared epitope (SE), the rheumatoid arthritis (RA) protection model, and the occurrence of anti-cyclic citrullinated peptide (anti-CCP) antibodies in RA patients from a genetically diverse population. One hundred and forty Brazilian RA patients and 161 matched controls were typed for HLA-DRB1 alleles using amplified DNA hybridized with sequence-specific oligonucleotide probes or primers. Patients were stratified according to the presence or absence of SE (DRB1*0401, *0404, *0405, *0101, *1001, and *1402), of the DERAA alleles (DRB1*0103, *0402, *1102, *1103, *1301, *1302, and *1304), and X (all other alleles). Anti-CCP antibodies were measured by ELISA. The combined frequency of...

Absence of linkage between MHC and a gene involved in susceptibility to human schistosomiasis

Palavras-chave: Susceptibility to rheumatoid arthritis; HLA; Brazilians; Shared epitope; Anti-cyclic citrullinated peptide.

Ano: 2008

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2008000600010

Chiarella,J.M.; Goldberg,A.C.; Abel,L.; Carvalho,E.M.; Kalil,J.; Dessein,A..

Six hundred million people are at risk of infection by Schistosoma mansoni. MHC haplotypes have been reported to segregate with susceptibility to schistosomiasis in murine models. In humans, a major gene related to susceptibility/resistance to infection by S. mansoni (SM1) and displaying the mean fecal egg count as phenotype was detected by segregation analysis. This gene displayed a codominant mode of inheritance with an estimated frequency of 0.20-0.25 for the deleterious allele and accounted for more than 50% of the variance of infection levels. To determine if the SM1 gene segregates with the human MHC chromosomal region, we performed a linkage study by the lod score method. We typed for HLA-A, B, C, DR and DQ antigens in 11 informative families from...

Association of leprosy with HLA-DR2 in a Southern Brazilian population

Palavras-chave: HLA; Linkage study; Human schistosomiasis.

Ano: 1998

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1998000500010

Genetic susceptibility to HPV infection and cervical cancer

The association between HLA specificities and leprosy was investigated in a Southern Brazilian population. One hundred and twenty-one patients and 147 controls were typed for HLA-A, B, Cw, DR and DQ. Patients were subdivided into the following subgroups, according to clinical, histological and immunological criteria: lepromatous (N = 55), tuberculoid (N = 32), dimorphous (N = 20), and indeterminate (N = 14). The frequencies of HLA specificities were compared between the total group of patients and controls, and between the same controls and each subgroup of patients. After correction of the probabilities, deviations were not significant, except for the DR2 specificity, which presented a frequency of 44.2% in the total group of patients and 56.3% in the...

Tipo: Info:eu-repo/semantics/other

Palavras-chave: HLA; Leprosy; Mycobacterium leprae.

Ano: 1997

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000100008

Maciag,P.C.; Villa,L.L..

Squamous cell carcinoma of the cervix (SCCC) is one of the leading causes of death in developing countries. Infection with high-risk human papillomavirus (HPV) is the major risk factor to develop malignant lesions in the cervix. Polymorphisms of the MHC and p53 genes seem to influence the outcome of HPV infection and progression to SCCC, although controversial data have been reported. MHC are highly polymorphic genes that encode molecules involved in antigen presentation, playing a key role in immune regulation, while p53 is a tumor suppressor gene that regulates cell proliferation. The HPV E6 protein from high-risk types binds p53 and mediates its degradation by the ubiquitin pathway. The role of these polymorphisms in genetic susceptibility to HPV...

HLA profile in patients with AIDS and tuberculosis

Palavras-chave: Human papillomavirus; Cervical cancer; HLA; P53; Polymorphism.

Ano: 1999

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999000700017

Figueiredo,José Fernando de Castro; Rodrigues,Maria de Lourdes Veronese; Deghaide,Neifi Hassam Saloum; Donadi,Eduardo Antonio.

Studies carried out in various populations have reported an association between some HLA specificities and susceptibility to tuberculosis. We investigated the class I and class II HLA profile in Brazilian patients of various ethnic backgrounds who had AIDS and tuberculosis. Twenty-two adult patients with AIDS and tuberculosis (Group I), 103 patients with AIDS without tuberculosis (Group II) and 423 healthy individuals not infected with HIV (Group III) were evaluated. Diagnosis of HIV infection was made by ELISA, confirmed by a gelatin particle agglutination test. Diagnosis of tuberculosis was made based on clinical/radiological presentation and direct bacilloscopy or clinical specimen cultures. Class I antigens were typed by microlymphotoxicity. Class II...

HLA-Bw4-B*57 and Cw*18 alleles are associated with plasma viral load modulation in HIV-1 infected individuals in Salvador, Brazil

Palavras-chave: AIDS; Tuberculosis; Host genetic factors; HLA.

Ano: 2008

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-86702008000400004

Silva,Edinete Melo da; Acosta,Angelina Xavier; Santos,Eduardo José Melo; Netto,Eduardo Martins; Lemaire,Denise Carneiro; Oliveira,Adriano Silva; Barbosa,Carolina Matos; Bendicho,Maria Teresita; Galvão-Castro,Bernardo; Brites,Carlos.

Host genetic factors play an important role in mediating resistance to HIV-1 infection and may modify the course of infection. HLA-B alleles (Bw4 epitope; B*27 and B*57) as well as killer cell immunoglobulin-like receptors have been associated with slow progression of HIV-1 infection. OBJECTIVE: To evaluate the association between serological epitopes HLA-Bw4 and HLA-Bw6 and prognostic markers in AIDS. METHODS: 147 HIV-infected individuals in Bahia, Northeast Brazil, were genotyped for HLA class I locus. HLA class I genotyping was performed by hybridization with sequence-specific oligonucleotide probes following amplification of the corresponding HLA-A, HLA-B and HLA-C genes. Statistical analysis was performed using Fisher's exact and ANOVA tests for...

Immunogenetics and infectious diseases: special reference to the mayor histocompatibility complex

Palavras-chave: HIV; AIDS; MHC; HLA; Polymorphism.

Ano: 2010

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-86702010000500008

Alves,Crésio; Souza,Thaisa; Meyer,Isadora; Toralles,Maria Betânia P.; Brites,Carlos.

Many studies have tried to identify genetic markers for infectious diseases, some of them have focused on human leukocyte antigens (HLA). The products of HLA genes interact with surface-specific receptors of T lymphocytes, resulting in activation of the host's immune response. Association of bacterial, viral, parasitic and fungal infections with the host's HLA has been widely investigated. The type and strength of this association differs among distinct populations, as well as among racial and/or ethnic groups. The new molecular methods for the identification of the HLA alleles, and the resulting new nomenclature, have contributed to a better understanding of this system. Unfortunately, this information has not been adequately transmitted to clinicians,...

Linkage disequilibrium and diversity for three genomic regions in Azoreans and mainland Portuguese

Palavras-chave: HLA; Infectious diseases; Major histocompatibility complex.

Ano: 2006

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-86702006000200010

Genet. Mol. Biol.

Branco,Claudia C.; Pacheco,Paula R.; Cabrol,Ester; Cabral,Rita; Vicente,Astrid M.; Mota-Vieira,Luisa.

Studies on linkage disequilibrium (LD) across the genome and populations have been used in recent years with the main objective of improving gene mapping of complex traits. Here, we characterize the patterns of genetic diversity of HLA loci and evaluate LD (D') extent in three genomic regions: Xq13.3, NRY and HLA. In addition, we examine the distribution of DXS1225-DXS8082 haplotype diversity in Azoreans and mainland Portuguese. Allele distribution has demonstrated that the São Miguel population is genetically very diverse; haplotype analysis revealed 100% discriminatory power for X- and Y-markers and 94.3% for HLA markers. Standardized multiallelic D' in these three genomic regions shows values lower than 0.33, thereby suggesting there is no extensive LD...

SISTEMA INMUNE Y GENÉTICA:: UN ABORDAJE DIFERENTE A LA DIVERSIDAD DE ANTICUERPOS

Palavras-chave: Linkage disequilibrium; X-chromosome; Y-chromosome; HLA; São Miguel; Azores.

Ano: 2009

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000200003

Acta biol.Colomb.

MATTA CAMACHO,NUBIA ESTELA.

Es común encontrar en los libros de inmunología o de genética un capítulo con el título de -sistema inmune y genética-, sin embargo su asociación se centra en cómo la generación de anticuerpos rompió el paradigma -un gen, una proteína-, pues en el caso de la producción de anticuerpos, un gen produce millones de proteínas. El sistema inmune tiene muchos vínculos con la genética y la herencia; esta asociación se da porque cualquier sustancia o compuesto que produzca un organismo, es un antígeno potencial cuando es reconocido como extraño por el sistema inmune de otro organismo, sea este de la misma o de diferente especie. La producción de proteínas que potencialmente pueden ser antigénicas están ligadas al genotipo del individuo. La capacidad de responder y...

URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-548X2011000300012

Palavras-chave: HLA; Respuesta inmune; Grupos sanguíneos; Antígenos.

Ano: 2011

Toxoplasmic encephalitis: role of Human Leucocyte Antigens/alleles associated with rapid progression to Acquired Immunodeficiency Syndrome

Rodrigues,Maria de Lourdes; Deghaide,Neifi Hassam; Figueiredo,José Fernando; de Menezes,Marcelo Bezerra; Demarco,Ana Lúcia; Donadi,Eduardo; Fernandes,Ana Paula.

Abstract Background/aims The frequency of Human Leucocyte Antigens/alleles associated with rapid progression from Human Immunodeficiency Virus infection to Acquired Immunodeficiency Syndrome was evaluated in Brazilian patients with Acquired Immunodeficiency Syndrome with and without Toxoplasmic Encephalitis. Methods 114 patients with Acquired Immunodeficiency Syndrome (41 with Toxoplasmic Encephalitis, 43 with anti-Toxoplasma gondii antibodies, without Toxoplasmic Eencephalitis, and 30 without anti-Toxoplasma gondii antibodies circulating and without Toxoplasmic Encephalitis) were studied. Results Human Leucocyte Antigens/alleles associated with rapid progression to Acquired Immunodeficiency Syndrome, particularly HLA-B35, -DR3, and -DR1 allele group,...