Ehrlichia under our noses and no one notices

摘要: Ehrlichia chaffeensis, an obligately intracellular bacterium, resides within a cytoplasmic vacuole in macrophages, establishes persistent infection natural hosts such as white-tailed deer and canids, is transmitted transstadially during feeding by ticks, particularly Amblyomma americanum. Ehrlichial cell walls contain glycoproteins family of divergent 28 kDa proteins, but no peptidoglycan or lipopolysaccharide. The dense-cored ultrastructural form preferentially expresses certain glycoproteins, including multiple repeat unit-containing adhesin. Ehrlichiae attach to L-selectin E-selectin, inhibit phagolysosomal fusion, apoptosis, JAK/STAT activation, downregulate IL-12, IL-15, IL-18, TLR2 3, CD14. Mouse models implicate overproduction TNF-α antigen-specific CD8 T lymphocytes pathogenesis strong type 1 CD4 lymphocyte responses, synergistic activities IFN-γ TNF-α, IgG2a antibodies immunity.