CD40LG and tick-borne encephalitis: To our knowledge, this is the first work that considers the evolution of IgM and IgG antibody responses to the C6 peptide and OspC and VlsE proteins of B. burgdorferi sensu lato in erythema-free ITBB patients as well as in EM and EMF patients coinfected with the agents of HGA or TBE.