B lymphocytes in inflammatory airway diseases.

B lymphocytes are key players in all facets of adaptive immune responses and are responsible for the production of IgE antibodies, initiators of allergic hypersensitivity reactions. Recent evidence indicates that B cells may be a crucial player in allergic and inflammatory airway pathology, directly populating upper and lower airway tissues. This review examines human and animal studies that directly demonstrated the presence of B lymphocytes in airway tissues and elaborates on their function as antibody-secreting cells, antigen-presenting cells and producers of inflammatory and regulatory cytokines.

Expression of IL-9 receptor alpha chain on human germinal center B cells modulates IgE secretion.

Background: IL-9 has been shown to affect the differentiation pathway of different cell types. However, its potential role in the maturation pathway of antigen-driven B-cell differentiation and its functional effects remain unknown.

Objective: To characterize IL-9 receptor alpha chain (IL-9R alpha) expression on human tonsillar B cells at different maturational stages, and to assess its effect on IgE production.

Regulation of IL-13 receptor alpha 1 expression and signaling on human tonsillar B-lymphocyte subsets.

Background: T(H)2 cytokines play crucial roles in driving human B lymphocytes to produce IgE. However, it is unclear whether IL-4 and IL-13 have parallel or sequential roles in the development of B lymphocytes.

Objective: We investigated IL-13 receptor (IL-13R) expression and regulation in mature and immature human B cells.

Synthesis of IL-13 by human B lymphocytes: regulation and role in IgE production.

Background: Our laboratory has demonstrated previously that human tonsillar B lymphocytes express IL-13 mRNA OBJECTIVE: We sought to investigate IL-13 production by human B cells and the association between B cell-derived IL-13 and IgE secretion.

Methods: Human B lymphocytes were isolated from tonsils and purified by means of rosetting with sheep RBCs or positive or negative selection with magnetic beads. They were stimulated with anti-CD40 antibodies with or without recombinant IL-4.

Auto-antibodies to the asialoglycoprotein receptor in sera of children with auto-immune hepatitis.

Unlabelled: Most studies on the prevalence of asialoglycoprotein antibodies have involved adults. In this study the prevalence of antibodies to the human asialoglycoprotein receptor (ASGP-R) was determined in 63 children with auto-immune hepatitis. It was shown that 75% of those with auto-immune hepatitis type 1 and 40% of those with auto-immune hepatitis type 2 were positive and the presence of anti-ASGP-R auto-antibodies, at a mean titre of 1:1,600 and 1:1,000 respectively.