Comparative Cellular Immune Responses in Calves after Infection with Mycobacterium avium subsp. paratuberculosis, M. avium subsp. avium, M. kansasii and M. bovis

Paratuberculosis infection is caused by Mycobacterium avium subsp. paratuberculosis (MAP). In the Netherlands, 75% herd level prevalence of caprine paratuberculosis has been estimated, and vaccination is the principal control strategy applied. Most goat dairy farms with endemic paratuberculosis systematically vaccinate goat kids in the first months of life with a commercially available whole cell MAP vaccine. We hypothesized that the development of adaptive immune responses in goats vaccinated at young age depends on the environment they are raised in, and this has implications for the application of immune diagnostic tests in vaccinated dairy goats. We evaluated the early immune response to vaccination in young goat kids sourced from a MAP unsuspected non-vaccinated herd and raised in a MAP-free environment. Subsequently we compared these with responses observed in birth year and vaccination matched adult goats raised on farms with endemic paratuberculosis. Results indicated that initial adaptive immune responses to vaccination are limited in a MAP-free environment. In addition, adult antibody positive vaccinated goats raised in a MAP endemic environment are less likely to be IS900 PCR-positive as compared to antibody negative herd mates. We conclude that test-and-cull strategies in a vaccinated herd are currently not feasible using available immune diagnostic tests.

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Humoral and cellular immune responses in sheep immunized with a 22 kilodalton exported protein of Mycobacterium avium subspecies paratuberculosis

Journal of Medical Microbiology ◽

10.1099/jmm.0.46785-0 ◽

2006 ◽

Vol 55 (12) ◽

pp. 1735-1740 ◽

Cited By ~ 14

Author(s):

Rachael C. Rigden ◽

Dakshina M. Jandhyala ◽

Chris Dupont ◽

Dianna Crosbie-Caird ◽

Nicolas Lopez-Villalobos ◽

...

Keyword(s):

Immune Responses ◽

Mycobacterium Avium ◽

Mycobacterium Avium Subspecies Paratuberculosis ◽

Specific Antibodies ◽

Antibody Recognition ◽

Cellular Immune Responses ◽

Exported Protein ◽

Cellular Immune

An immunogenic 22 kilodalton exported Mycobacterium avium subspecies paratuberculosis (MAP) lipoprotein (P22) was previously identified, and found to belong to the LppX/LprAFG family of mycobacterial lipoproteins. N-terminal polyhistidine-tagged P22 was produced and purified from Escherichia coli. Antibody recognition of P22, and interferon-gamma (IFN-γ) responses in vitro using blood from a sheep vaccinated with Neoparasec, confirmed its immunogenicity. To evaluate the immunogenicity of P22 in vivo, five sheep were immunized with a single dose containing 0.8 mg recombinant P22 protein in adjuvant. Blood was collected at 4, 13 and 29 weeks post-immunization (p.i.) and tested for anti-P22 antibodies and P22-specific IFN-γ production. P22-specific antibodies were detected by Western blot analysis in all five Neoparasec-immunized sheep at the three time points. Three out of five P22-immunized sheep produced P22-specific antibodies for up to 13 weeks p.i., and two gave a response at 29 weeks p.i. Recombinant P22 was able to stimulate significant IFN-γ production in blood of P22-immunized sheep at 13 and 29 weeks p.i. Recombinant P22 also elicited an IFN-γ response in blood of sheep immunized with Neoparasec.

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