Absence of effects of thymopentin on murine host resistance to Listeria monocytogenes.
The effects of various doses of Thymopentin, the synthetic 5 aminoacid fragment of thymopoietin injected on d -4 and d -1 on murine host resistance to Listeria monocytogenes were tested. The experiments did not reveal any regular dose-effect relationship; i.e. no or only marginal (more often small negative rather than positive) effects were observed on clearance and on resistance neither during the T cell independent first hour or the first 2 days of infection in euthymic or thymus deficient nude mice, nor during the T cell dependent phase after 2 days of infection in euthymic mice. Also survival of mice was not increased in a regular dose-effect relationship with dose ranges of Thymopentin from 0.3 ng-30 mg per 30 g mouse; furthermore, injections of 3 micrograms per 30 g mouse for varying time intervals from -3 days before up to 6 days after infection had no protective effect. Thus Thymopentin apparently does not induce measurable macrophage activation directly or cannot increase macrophage activation mediated by T cells in euthymic mice nor does it induce adequate T cell responses in nude mice to promote improved resistance to Listeria.
Rüttner
B
B
Institute of Pathology, University of Zürich, Switzerland.
Hauser
T
T
Leist
T P
TP
Zinkernagel
R M
RM
D000818:Animals; D007113:Immunity, Innate / Q000187:drug effects; D007371:Interferon-gamma / Q000502:physiology; D007928:Lethal Dose 50; D008089:Listeria monocytogenes / Q000276:immunology* / Q000472:pathogenicity; D051379:Mice; D008810:Mice, Inbred C57BL; D016305:Thymopentin / Q000494:pharmacology*
D007371:Interferon-gamma; D016305:Thymopentin