|Araujo, Ricardo - DEPT PARASIT. BRAZIL|
|Padilha, Terezinha - EMBRAPA, BELTSVILLE MD|
Submitted to: American Association of Veterinary Parasitologists Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: May 23, 2002
Publication Date: May 30, 2002
Citation: ARAUJO, R., SONSTEGARD, T.S., ZARLENGA, D.S., PADILHA, T., GASBARRE, L.C. USE OF A CANDIDATE GENE ARRAY TO DELINEATE GENE EXPRESSION IN CATTLE SELECTED FOR RESISTANCE OR SUSCEPTIBILITY TO GASROINTESTINAL NEMATODES. AMERICAN ASSOCIATION OF VETERINARY PARASITOLOGISTS PROCEEDINGS. p. 47, 2002. Technical Abstract: The purpose of this study was to investigate the expression of subsets of genes with known association to host immune responses in cattle susceptible or resistant to gastrointestinal nematode infection. Target sequences were selected from previously characterized genes or from EST sequences derived from USDA bovine cDNA libraries after comparison to ortholog sequences in GenBank, and 192 genes were PCR amplified, purified and printed onto glass slides for microarray analysis. Slides were hybridized with fluorescent-labeled cDNA generated from abomasal mucosal and abomasal lymph node RNA from animals with previously characterized resistance phenotypes. In slides hybridized with cDNA derived from abomasal lymph nodes, resistant animals showed an elevation in genes transcripts related to tissue repair, while gene transcripts related to immune system activation, especially immunoglobulin genes, were elevated in susceptible animals. Expression related to inflammatory responses was elevated in both groups; however susceptible animals showed higher levels in gene sequences related to specific immune responses, whereas resistant animals had elevated expression levels in genes associated with innate immune responses. In contrast, slides hybridized with the abomasal mucosa cDNA showed marked expression in genes related to immunoglobulins and IFN transcription in resistant animals. Susceptible animals, on the other hand, had higher transcription levels of cDNAs related to cell attraction, cell migration, complement, and NO metabolism. Genes related to tissue repair, transmembrane communication and cell-cell interaction showed no discernable patterns in either resistant or susceptible animals. These results demonstrate that the immune response against gastrointestinal nematodes is very complex and that two tissues intimately involved in immunity, the abomasal mucosa and abomasal lymph nodes, can present very different patterns of gene expression.