Abstract
Abstract The beta-2-adrenergic receptor (β2-AR) is one of the β-AR subsets found in most immune cells and is stimulated by norepinephrine (NE) binding. We showed previously that exposure of a mouse model to cold water stress leads to high level production of NE that may result in increased intensity of Chlamydia muridarum genital infection but the mechanism is not well defined. The purpose of this study was to develop and characterize a β2-AR knockout (KO) stress mouse model to investigate its susceptibility to C. muridarum genital infection. We hypothesized that lacking the β2-AR leads to a decreased C. muridarum shedding from the genital tract of stressed mice compared to that of stressed wild type (WT) mice. Stressed and non-stressed C57BL/6J WT and β2-AR KO mice were infected intravaginally with C. muridarum. Swabbing at 3-day intervals during primary infection and C. muridarum isolation was performed by culturing in McCoy tissue culture following standard methods. β2-AR KO stressed mice had a mean of 8540 inclusion forming units/ml (IFU/ml) compared to a mean of 18000 IFU/ml of stressed wild type at day 9 post infection. The overall course of primary infection in the β2-AR KO mouse model showed slightly reduced Chlamydia shedding. In addition, transfer of CD4+ T cells from black J6 WT to β2-AR KO resulted in a significant increase of shedding compared to that of non-stressed WT transfer (6000 versus 1000 IFU/ml). Secretion of interferon gamma was restored in β2-AR KO mice compared to WT. Overall, these results imply that deficiency in β2-AR leads to decreased C. muridarum shedding compared to the WT. However, other members of the alpha- and beta-adrenergic receptor family may compensate for the absence in β2-AR KO mice thus more investigation is needed.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call