Moreover, skin lesions (erythema migrans, an early clinical manifestation of Lyme disease) of patients with Lyme disease, a tick-borne zoonosis caused by Borrelia burgdorferi (B. burgdorferi), have a clonally expanded population of GzmK+CD8+T cells secreting IFN-γ but exhibit less cytotoxic action (Figure 5) [308]. The gene discussed is GZMK; the disease is Lyme disease.