R W Sweeney1, D E Jones, P Habecker, P Scott. 1. Department of Clinical Studies-New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square 19348, USA.
Abstract
OBJECTIVE: To determine whether clinical progression of paratuberculosis in cattle was associated with alterations in cytokine gene expression in affected tissues. ANIMALS: 5 uninfected adult Holstein cows, 7 adult Holstein cows naturally infected with Mycobacterium paratuberculosis that did not have clinical signs of disease, and 4 adult Holstein cows naturally infected with M paratuberculosis that had progressive clinical signs of infection. PROCEDURE: Samples of ileum and cecal lymph nodes were obtained from each animal at the time of slaughter. A reverse transcriptase-competitive polymerase chain reaction assay was used to determine mRNA expression of interferon-gamma (IFN-gamma) and interleukin 4 in each sample. RESULTS: Interferon-gamma gene expression was significantly higher in ileum and cecal lymph node samples from subclinically infected cows than from clinically infected cows. CONCLUSIONS AND CLINICAL RELEVANCE: Progression of paratuberculosis to clinical stages is associated with reduced expression of IFN-gamma at site of infection. If immune response to M paratuberculosis can be manipulated so that IFN-gamma expression is increased, resistance to infection in cattle might be enhanced.
OBJECTIVE: To determine whether clinical progression of paratuberculosis in cattle was associated with alterations in cytokine gene expression in affected tissues. ANIMALS: 5 uninfected adult Holstein cows, 7 adult Holstein cows naturally infected with Mycobacterium paratuberculosis that did not have clinical signs of disease, and 4 adult Holstein cows naturally infected with M paratuberculosis that had progressive clinical signs of infection. PROCEDURE: Samples of ileum and cecal lymph nodes were obtained from each animal at the time of slaughter. A reverse transcriptase-competitive polymerase chain reaction assay was used to determine mRNA expression of interferon-gamma (IFN-gamma) and interleukin 4 in each sample. RESULTS:Interferon-gamma gene expression was significantly higher in ileum and cecal lymph node samples from subclinically infected cows than from clinically infected cows. CONCLUSIONS AND CLINICAL RELEVANCE: Progression of paratuberculosis to clinical stages is associated with reduced expression of IFN-gamma at site of infection. If immune response to M paratuberculosis can be manipulated so that IFN-gamma expression is increased, resistance to infection in cattle might be enhanced.
Authors: W R Waters; J M Miller; M V Palmer; J R Stabel; D E Jones; K A Koistinen; E M Steadham; M J Hamilton; W C Davis; J P Bannantine Journal: Infect Immun Date: 2003-09 Impact factor: 3.441