Kinetics of monocytoid B lymphocytes in localized inflammatory lesions induced by lipopolysaccharide in mice.
Immunohistochemistry was used to study the kinetics of B lymphocytes (B-lys) in the early stages of the localized inflammatory response induced in SMA mice by the subcutaneous injection of lipopolysaccharide (LPS). At the injection sites, medium-sized B-lys formed early inflammatory lesions with neutrophils and activated macrophages on days 1 and 2. The B-lys were morphologically similar to monocytes, but were not stained with Mac1 antibody. Remarkably the B-lys showed the phenotypes of B220+, IgM+, IgD (slight to negative), Ly-1- and CD23- by double immunohistochemical staining. The B-lys were also positive for alkaline phosphatase. Consequently the B-lys could be identified as monocytoid B-lys or marginal zone B-lys. Plasmacytic B-lys and plasma cells were first observed on days 3 and 4, but no lymphoid follicles were found at the injection sites. In the inguinal lymph nodes, the same B-lys responses were mainly induced in the paracortical lesions (T cell areas) preceding the formation of activated germinal centers (GC). These findings suggested that the B-lys, induced by injections of LPS, matured into plasma cells in the localized inflammatory lesions independent of GC, and that they were different from follicular B-lys.
Fujino
M
M
First Department of Pathology, Nagoya University, School of Medicine, Japan.
Ohbayashi
M
M
Ohmiya
N
N
Kato
N
N
Asai
J
J
Ito
M
M
D000818:Animals; D001402:B-Lymphocytes / Q000187:drug effects* / Q000473:pathology; D002453:Cell Cycle; D006119:Groin; D007150:Immunohistochemistry; D007249:Inflammation / Q000139:chemically induced / Q000276:immunology*; D007279:Injections, Subcutaneous; D007711:Klebsiella pneumoniae / Q000737:chemistry; D008070:Lipopolysaccharides; D008198:Lymph Nodes / Q000276:immunology*; D051379:Mice; D008815:Mice, Inbred Strains; D013154:Spleen / Q000276:immunology; D013997:Time Factors
D008070:Lipopolysaccharides