Repeat tuberculin skin testing leads to desensitisation in naturally infected tuberculous cattle which is associated with elevated interleukin-10 and decreased interleukin-1 beta responses

Vet Res. Mar-Apr 2010;41(2):14. doi: 10.1051/vetres/2009062. Epub 2009 Oct 20.

Abstract

The principal surveillance tool used to control bovine tuberculosis in cattle is the removal of animals that provide a positive response to the tuberculin skin-test. In this study we performed a longitudinal investigation of the immunological and diagnostic consequences of repeated short-interval skin-tests in cattle naturally infected with Mycobacterium bovis. Tuberculin skin-test positive cattle were subjected to up to four further intradermal comparative cervical skin-tests at approximately 60-day intervals. A significant progressive reduction in the strength of the skin-test was observed after successive tests. In contrast, the magnitude of interferon-gamma (IFN-gamma) responses was not influenced by repeat skin-testing either transiently around the time of each skin-test or longitudinally following repeated tests. A significant boost in blood interleukin-10 (IL-10) production was observed within 3 days following each skin-test although the magnitude of this boosted response returned to lower levels by day 10 post-test. The application of a novel multiplex assay to simultaneously measure seven cytokines and chemokines also identified that skin-testing resulted in a significant and progressive reduction in antigen specific interleukin-1beta (IL-1beta) whilst confirming stable IFN-gamma and elevated IL-10 responses in the blood. Therefore, we have demonstrated that in cattle naturally infected with M. bovis, repeat short-interval skin-testing can lead to a progressive reduction in skin-test responsiveness which has potential negative consequences for the detection of infected animals with marginal or inconclusive skin-test responses. The desensitising effect is associated with decreased IL-1beta and elevated IL-10 responses, but importantly, does not influence antigen specific IFN-gamma responses.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cattle
  • Cattle Diseases / diagnosis
  • Cattle Diseases / metabolism*
  • Desensitization, Immunologic / veterinary*
  • Interferon-gamma / blood
  • Interferon-gamma / metabolism
  • Interleukin-10 / blood
  • Interleukin-10 / metabolism*
  • Interleukin-1beta / blood
  • Interleukin-1beta / metabolism*
  • Time Factors
  • Tuberculin Test / veterinary*
  • Tuberculosis / diagnosis
  • Tuberculosis / metabolism
  • Tuberculosis / veterinary*

Substances

  • Interleukin-1beta
  • Interleukin-10
  • Interferon-gamma