Persistent Borrelia Burgdorferi Infection: CD4 T Cell Responses
Elizabeth M. Hammond, et al., published a study in Current Opinion in Immunology investigating the correlation between persistent Borrelia burgdorferi (Bb), infections, and CD4 T cell responses in August 2022. The study found that in mice infected with Bb, the pathogen triggers CD4 T cell activation in secondary lymphoid tissues, from which they spread into other diseased tissues. Regardless of their activation and the occurrence of CD4 T cell-dependent antibody responses, Bb generates persistent infection in natural Bb reservoir hosts, despite the absence of apparent disease, which brings into question the effectiveness of the anti-Bb T cell responses.
After reviewing the available literature, the researchers suggest that CD4 T cells may establish a host cell target of Bb-mediated immune evasion, which makes these cells unsuccessful in creating effective inflammatory responses and unable to support highly efficient Bb-specific antibody generation. This indicates that enhancing the stimulation of more efficient CD4 T cell responses may assist with overcoming persistent Bb infections.
Other highlights from the study include:
- Numerous immune evasion strategies advance persistent Bb infections.
- CD4 Th1 polarization is linked with Bb-induced infection not protection.
- Protective Th2 and Th17 polarization are not generated to Bb infections.
- Strong Tfh production yet diminished T-dependent B cell responses after Bb infections.