Polymorphonuclear Neutrophils Are Necessary for the Recruitment of CD8⁺T Cells in the Liver in a Pregnant Mouse Model of<i>Chlamydophila abortus</i>(<i>Chlamydia psittaci</i>Serotype 1) Infection

Abstract

ABSTRACT The role of polymorphonuclear neutrophils (PMNs) in the development of the specific immune response against Chlamydophila abortus ( Chlamydia psittaci serotype 1) infection was studied in a pregnant mouse model involving treatment with RB6-8C5 monoclonal antibody. PMN depletion significantly affected the immune response in the liver, in which the T-lymphocyte and F4/80 + cell populations decreased, particularly the CD8 + T-cell population. A Th1-like response, characterized by high levels of gamma interferon without detectable levels of interleukin 4 (IL-4) in serum, was observed in both depleted and nondepleted mice, although an increased production of IL-10 was detected in the depleted group. Our results suggest that PMNs play a very important role in the recruitment of other leukocyte populations to the inflammatory foci but have little influence in the polarization of the immune specific response toward a Th1-like response.