Cloning, sequencing, and cell surface expression pattern of bovine immunoreceptor NKG2D and adaptor molecules DAP10 and DAP12.

NKG2D is an activating lectin-like receptor that initiates natural killer (NK) cell responses against transformed tumor cells expressing its ligands, i.e., molecules related to major histocompatibility complex (MHC) class I molecules.

Costimulatory molecule requirement for bovine WC1+gammadelta T cells' proliferative response to bacterial superantigens.

We have previously shown that the proliferation of freshly isolated bovine WC1+gammadelta T cells to superantigens (SAgs) including staphylococcal enterotoxin A (SEA), and staphylococcal enterotoxin B (SEB) or toxic shock syndrome type-1 (TSST-1) required the presence of antigen-presenting cells (APC) and the addition of exogenous interleukin (IL)-2. The costimulatory activity provided by molecules expressed on professional APC for the proliferation of gammadelta T cells has not been addressed hitherto. In the present study, we investigated the ability of two selected APC populations, the dendritic cells (DCs) highly expressing CD80 and CD86 molecules (CD80highCD86high) and the monocytes expressing the same molecules at a rather low level (CD80lowCD86low), to stimulate the proliferation of purified bovine WC1+gammadelta T cells to SAgs.

Purified bovine WC1+ gamma delta T lymphocytes are activated by staphylococcal enterotoxins and toxic shock syndrome toxin-1 superantigens: proliferation response, TCR V gamma profile and cytokines expression.

In this study, the ability of purified bovine gammadelta T cells in vitro to be activated by superantigens (SAg) was investigated. Freshly isolated WC1(+) gammadelta T cells, in the presence of autologous glutaraldehyde-fixed or gamma-irradiated antigen presenting cells (APC) and IL-2, were incubated with staphylococcal enterotoxins A and B (SEA and SEB), and toxic shock syndrome toxin-1 (TSST-1). Both a proliferative response and the expression of particular T cell receptor genes of the gamma variable (TCR Vgamma) repertoire family were induced.

Purification and characterisation of bovine WC1+ gammadelta T lymphocytes from peripheral blood.

In order to isolate and characterise resting WC1+ gammadelta T cells from cattle, we developed a protocol for purifying these cells by negative selection from peripheral blood. The purification method included five steps: separation of mononuclear cells on lymphoprep, depletion of monocytes by adherence to plasma-coated gelatin, enriching T cells on a nylon wool column, depleting CD2+ T cells by sheep red blood cells (SRBC), and finally depleting CD4+ and CD8+ T cells by the magnetic cell sorting technique (MACS). This procedure proved efficient and reproducible, and the purity of the isolated WC1+ gammadelta T cells was more than 97% as analysed by flow cytometry (FACS).

IgG humoral response against the antigen 85 complex homologues in leprosy.

Antigen 85 complex is the major protein component present in M. bovis BCG culture filtrate (CF). It consists of a family of three proteins: 85A, 85B and 85C.