Characterisation of the lymph node immune response followingMycoplasma mycoidessubsp.MycoidesSC infection in cattle

Abstract

-Contagious bovine pleuropneumonia (CBPP), caused by Mycoplasma mycoides subsp. mycoides biotype Small Colony (MmmSC

Analysis of cellular responses toMycoplasma mycoidessubsp.mycoidessmall colony biotype associated with control of contagious bovine pleuropneumonia

“…In contrast, after 6 days in vitro, CD4 + T cells largely outnumbered all other subsets among CFSElow cells, which resulted in a substantial enrichment of cultures for CD4. These results provide an explanation to previous studies reporting a lack of enrichment for CD4 despite strong activation (i.e., upregulation of CD25) in 5-day-old stimulated cultures [8] and underline the benefits of using CFSE loading in analysis of recall responses. Because of concomitant B-cell proliferation, changes in frequencies of CD4 + T cells was not detected before day 6 while proliferation of these cells was measured as early as day 4 using the CFSE method.…”

“…In summary, the results presented here extend previous results [7,8] and further support the idea that Th1 memory lymphocytes are involved in the control of CBPP. Vigorous proliferative and T1 biased cytokine recall responses, with a predominant contribution of CD4 + T cells, were observed in cattle that have recovered from CBPP, but not in animals developing the acute form of the disease.…”

“…Protective memory cells must be capable of expansion and rapid effector functions upon reencounter with the pathogen [21,28]. Previous work has shown that activation of CD4 + T cells and IFN-γ production are detected in animals that have recovered from CBPP, thus suggesting a role for these responses in protection [7,8]. However, direct evidence of proliferation, expression of memory markers, and IFN-γ production by CD4 + T cells or any other lymphocyte subsets in response to MmmSC is lacking.…”

Pulmonary and serum antibody responses elicited in zebu cattle experimentally infected withMycoplasma mycoidessubsp.mycoidesSC by contact exposure

“…In CBPP, while short term immunity is elicited by vaccination and long term immunity after recovery, very little is known regarding the mechanisms by which this protection is mediated [16,22]. In a recent study we demonstrated the involvement of cellular immunity in the MmmSC-specific protective immune response [5,6]. However, since CBPP is a respiratory disease, the local humoral response should also play a key role in protection by inhibiting MmmSC growth and potential attachment to host cells.…”

Identification of Mycoplasma mycoides subsp. mycoides Small Colony Genes Coding for T-Cell Antigens

“…Previous work indicated that CD4 ϩ T cells make a major contribution to the vigorous T1-biased anamnestic cellular immune response observed for cattle that have recovered from infection (2,3,18). More recently, we demonstrated that MmmSC-specific memory CD4 ϩ T cells comprise two phenotypically and functionally different subsets (19).…”