Vaccination of mice with attenuated mutants ofListeria monocytogenes: requirement for induction of macrophage la expression

The CtsR regulator of Listeria monocytogenes contains a variant glycine repeat region that affects piezotolerance, stress resistance, motility and virulence

“…Overall, it seems that CtsR and the Clp proteins have a highly fine‐tuned role in virulence and stress response. Further investigation of the role of stress response systems in the virulence of L. monocytogenes may contribute to the rational design of attenuated bacterial vaccines and vaccine delivery systems, in which attenuated bacteria should infect and persist for long enough to provoke protective immunity without causing symptoms of disease (Von Koenig et al ., 1982; Gahan and Collins, 1995; Guzman et al ., 1997).…”

The use ofListeria monocytogenesas a DNA delivery vector for cancer gene therapy

“…Attenuation through mutation of classical virulence factors would therefore affect the efficacy of our system. It is likely that other approaches, such as the creation of auxotrophic mutants, as described by others, 15,16 will have to be implemented when developing L. monocytogenes bactofection vehicles so as to retain intracellular growth and cell spread but limit virulence for the host. It will be a challenge to select the correct mutant strain to provide an adequate level of vector amplification in vivo whilst maintaining a significant degree of attenuation to ensure safety.…”