Marginal Zone Macrophages and Immune Responses Against Viruses

Abstract

The effective establishment of antiviral protection requires a coordinated interplay between the innate and adaptive immune system. Using osteopetrotic (op−/−) mice, this study investigated the influence of marginal zone macrophages in controlling and initiating a protective immune response against a cytopathic vs a non- or low-cytopathic virus. Despite the generation of potent adaptive immune responses, antiviral protection against cytopathic vesicular stomatitis virus critically depended on the presence of marginal zone macrophages. Infection with low doses (100 PFU) of non- or low-cytopathic lymphocytic choriomeningitis virus was rarely cleared and usually resulted in a carrier state in the majority of mice. This shows that the early innate immune system provides an important preparatory phase to the adaptive immune system and is particularly important for antiviral protection.

B Cells Are Crucial for Both Development and Maintenance of the Splenic Marginal Zone

“…4B), which serve as model Ags for bacterial capsules. Furthermore, it has also been reported that lack of mature B cells and macrophages in the marginal zone correlates with susceptibility to viral infections (48,49), because these macrophages are capable of controlling virus spread during the acute phase (50). In this respect, our findings may also be important from a clinical point of view.…”

Type I IFN-Mediated Protection of Macrophages and Dendritic Cells Secures Control of Murine Coronavirus Infection

“…Marginal zone macrophages in spleen can bind viruses decorated by complement and natural Abs and reduce thereby dissemination of viruses to peripheral organs (35). This trapping of viral particles on macrophages is important to enhance the induction of protective T cell responses (36). It has been shown that the enhanced binding of viral particles to macrophages also fosters their infection (37).…”

The presence of MOMA‐2+ macrophages in the outer B cell zone and protection of the splenic micro‐architecture from LPS‐induced destruction depend on secreted IgM

“…1A). Within the splenic marginal zone three different populations of macrophages positive for ER-TR9, MOMA-1, and 2F8 were previously described, organized in rings, where MOMA-1 + macrophages are located close to the white pulp within the marginal zone, surrounded by ER-TR9 + -and 2F8 + macrophages on the outside [4,[9][10][11][12][13][14]. Of the different macrophage subsets resident in the marginal zone 2F8 + scavenger receptor macrophages bound FITC-labeled LPS and no difference could be found between sIgM-deficient and WT mice ( Fig.…”

“…The marginal zone contains B cells flanking the marginal sinus and different subpopulations of highly phagocytic macrophages that are very effective in capturing immune complexes from the passing bloodstream. The outer population of marginal zone macrophages of the spleen express scavenger receptors (2F8) on the surface and is loosely organized, while the inner ring of marginal zone metallophilic (MOMA-1) macrophages, at the border to the white pulp, is tightly structured [8][9][10][11]. In this particular environment, marginal zone CD21 + CD35 + CD19 + IgM + B cells can produce IgM locally and after stimulation marginal zone B cells can proliferate and differentiate to IgM-producing plasma cells [12].…”