Dendritic Cells Induce CD4⁺ and CD8⁺ T‐Cell Responses to Mycobacterium bovis and M. avium Antigens in Bacille Calmette Guérin Vaccinated and Nonvaccinated Cattle

Abstract

Few data are available regarding the induction of memory T-lymphocyte responses in cattle following Bacille Calmette Guérin (BCG) vaccination. Studies of the immune response induced by BCG vaccination provide an insight into the basis of antimycobacterial immunity that could be exploited for the development of more effective vaccination strategies. We used autologous dendritic cells (DC) infected with Mycobacterium bovis Bacille Calmette Guérin (BCG) or pulsed with purified protein derivative from M. bovis (PPD-B) or M. avium (PPD-A) to assess responses of CD4+, CD8+ and WC1+ gammadelta TCR+ lymphocytes from BCG vaccinated and nonvaccinated cattle. Mycobacteria-specific CD4+ and CD8+, but not WC1+ gammadelta TCR+, memory T lymphocytes were demonstrated in BCG-vaccinated cattle. CD4+ and CD8+ lymphocytes proliferated and produced interferon (IFN)-gamma in response to BCG-infected or PPD-B-pulsed DC. Proliferative responses were greater for CD4+ than CD8+ lymphocytes, although secretion of IFN-gamma was higher from the CD8+ T cells. Responses to PPD-A-pulsed DC were lower, with no CD8+ response. Lymphocytes from nonvaccinated calves were also stimulated to proliferate by BCG-infected DC, although the magnitude of proliferation was lower. The findings suggest that immunity to M. bovis induced by BCG vaccination in cattle may involve CD8+ memory T cells which produce IFN-gamma, as well as CD4+ memory T cells.

Differential effects of bovine viral diarrhoea virus on monocytes and dendritic cells

“…DCs, or more accurately monocyte-derived dendritic cells, were generated from CD14 + monocytes as previously described (Hope et al, 2000). Monocytes were adjusted to 8610 5 cells ml 21 in tissue culture medium (TCM) [RPMI 1640 containing Glutamax-1 (Life Technologies), 10 % heat inactivated foetal calf serum, 5610 25 M b-mercaptoethanol, 50 mg gentamicin ml 21 ], plus 200 U COS-7 cellderived bovine rIL-4 ml 21 and 0?2 U bovine rGMCSF ml 21 (units based on induction of half maximal proliferation in bone marrow precursor cells).…”

“…These cells and mock-infected cells were used as APCs with allogeneic CD4 + T lymphocytes or MHC-identical CD4 + T lymphocytes from ovalbumin-immunized animals. CD4 + T lymphocytes were purified from PBMCs by staining with mAb CC8 and purifying cells with anti-mouse IgG labelled superparamagnetic beads (Miltenyi-Bitech), as described previously (Hope et al, 2000). In some experiments the APCs were incubated with ovalbumin (125 mg ml…”

Two Phenotypically Distinct Subsets of Spleen Dendritic Cells in Rats Exhibit Different Cytokine Production and T Cell Stimulatory Activity

“…It is interesting to note that CD4 Ϫ spleen DC express high levels of CD200, a molecule that has recently been involved in T cell tolerance (40). SIRP␣ ϩ and SIRP␣ Ϫ DC subsets have been described in bovine afferent lymph (41). Similar to rat DC, bovine SIRP␣ Ϫ DC were found to be poor stimulators of CD8 ϩ T cell responses, as compared with SIRP␣ ϩ DC, and this difference was related to the lack of IL-1 secretion by SIRP␣ Ϫ DC (41).…”

DNA-Encoded Fetal Liver Tyrosine Kinase 3 Ligand and Granulocyte Macrophage-Colony-Stimulating Factor Increase Dendritic Cell Recruitment to the Inoculation Site and Enhance Antigen-Specific CD4+ T Cell Responses Induced by DNA Vaccination of Outbred Animals

“…To generate a construct expressing GM-CSF, the open-reading frame encoding bovine GM-CSF was PCR-amplified from pTargetGM-CSF (34). The forward primer (5Ј-ATAGATATCATGTGGCTG CAGAACCTGCTTCTCC-3Ј) introduced an EcoRV restriction site (in italics) at the 5Ј end and the reverse primer (5Ј-TATGGATCCTCACT TCTGGGCTGGTTCCCAGC-3Ј) introduced a BamHI restriction site (in bold) at the 3Ј end.…”