Characterization of gene polymorphisms related to immune system physiology in Mangalarga horses / Caracterização de polimorfismos gênicos relacionados à fisiologia do sistema imune em equinos da raça Mangalarga

The objectives of this study were to standardize a PCR-RFLP genotyping method for the AY_731081:g.1900T>C SNP of the equine CD14 gene, and to characterize this SNP and two other polymorphisms (AY_005808: c.1530A>G of the TLR4 gene and AX_463789: g.133T>C of the Cε gene) in Mangalarga horses, in order to contribute to future studies investigating the association between DNA markers and traits related to immune system physiology in this breed. A total of 151 Mangalarga horses of both sexes and variable ages, representative of the population of São Paulo State, were used. PCR-RFLP was found to be adequate for genotyping of the AY_731081: g.1900T>C SNP of the equine CD14 gene. However, this polymorphism is probably not present in Mangalarga horses, thus impairing association studies using this marker in the breed. The population genetic parameters obtained for the TLR4 AY_005808:c.1530A>G and Cε AX_463789:g.133T>C polymorphisms suggest the use of these markers in association studies with immune system-related traits in Mangalarga horses.(AU)

Os objetivos deste trabalho foram a padronização da metodologia PCR-RFLP para genotipagem do SNP AY_731081:g.1900T>C do gene CD14 equino, bem como a caracterização em equinos da raça brasileira Mangalarga deste e de outros dois polimorfismos, o AY_005808: c.1530A>G do TLR4 e o AX_463789: g.133T>C do Cε, a fim de promover o embasamento necessário para futuras pesquisas visando à associação entre marcadores de DNA e características relacionadas à fisiologia do sistema imune na raça. Para tanto, foram utilizados 151 animais Mangalarga, de ambos os sexos e de idades variadas, representativos da população do estado de São Paulo. O método de PCR-RFLP mostrou-se adequado para a genotipagem do SNP AY_731081: g.1900T>C do gene CD14 equino. Entretanto, tal polimorfismo provavelmente não ocorre em equinos Mangalarga, impossibilitando estudos de associação com o marcador na raça. Os parâmetros genético-populacionais obtidos para os polimorfismos AY_005808:c.1530A>G do gene TLR4 e o AX_463789:g.133T>C do gene Cε demonstraram a possibilidade de realização de pesquisas.(AU)

Acute and chronic histopathologic changes in wild typeTLR-2-/-, TLR-4-/-, TLR-6-/-, TLR-9-/-, CD14-/-, and MyD-88-/- mice experimentally infected with Plasmodium chabaudi

Malaria is caused by protozoan parasites of the genus Plasmodium, which is transmitted by Anopheline mosquitoes. Experimental murine models using rodent malaria are useful for studying pathologic aspects of severe malaria. We evaluated histopathologic lesions of TLR-2-/-, TLR-4-/-, TLR-6-/-, TLR-9-/-, CD14-/- and MyD88-/- mice experimentally infected with Plasmodium chabaudi. Frequencies and severity of microscopic lesions in the spleen and liver at one and four weeks post infection (wpi) were determined. At one wpi, adherence of macrophages to the endothelial surface was the most evident change, whereas at four wpi there was marked accumulation of cytoplasmic pigment in macrophages in the liver and spleen. Lesions were not markedly influenced by the absence of TLRs, MyD88 or CD14. Our findings suggest that acute and chronic phases of murine infection with P. chabaudi are characterized by distinct lesions. In addition, TLRs and MyD88 are not essential to promote these lesions during P. chabaudi infection.(AU)

Acute and chronic histopathologic changes in wild type or TLR-2-/-, TLR-4-/-, TLR-6-/-, TLR-9-/-, CD14-/-, and MyD-88-/- mice experimentally infected with Plasmodium chabaudi

Malaria is caused by protozoan parasites of the genus Plasmodium, which is transmitted by Anopheline mosquitoes. Experimental murine models using rodent malaria are useful for studying pathologic aspects of severe malaria. We evaluated histopathologic lesions of TLR-2-/-, TLR-4-/-, TLR-6-/-, TLR-9-/-, CD14-/-, and MyD-88-/- mice experimentally infected with Plasmodium chabaudi. Frequencies and severity of microscopic lesions in the spleen and liver at one and four weeks post infection (wpi) were determined. At one wpi, adherence of macrophages to the endothelial surface was the most evident change, whereas at four wpi there was marked accumulation of cytoplasmic pigment in macrophages in the liver and spleen. Lesions were not markedly influenced by the absence of TLRs, MyD88 or CD14. Our findings suggest that acute and chronic phases of murine infection with P. chabaudi are characterized by distinct lesions. In addition, TLRs and MyD88 are not essential to promote these lesions during P. chabaudi infection.