Comparison of nasal steroid with antihistamine in prophylactic treatment against pollinosis using an environmental challenge chamber.

Environmental challenge chambers (ECC) have been used to expose people to pollen allergens within a stable atmosphere and to examine the efficacy of treatment. Although pollinosis is one of the typical IgE-mediated type I allergic diseases, allergic inflammation is thought to contribute to the fundamental pathogenesis and prophylactic treatment may reduce exacerbations of pollinosis. The purpose of this study was to compare the efficacy of prophylactic treatment with nasal steroid (mometasone furoate nasal spray) or an antihistamine (fexofenadine) in the control of cedar pollinosis using the ECC.

Immunological parameters associated with the development of allergic rhinitis: a preliminary prospective study.

Background: Many subjects are sensitized to Japanese cedar pollen but do not develop allergic rhinitis (AR). The aim of this study was to examine the immunologic parameters related to the development of AR in sensitized subjects.

Methods: The subjects were 33 adults who were sensitized to Japanese cedar pollen, but had not developed as of 2007.

Sublingual administration of Lactobacillus paracasei KW3110 inhibits Th2-dependent allergic responses via upregulation of PD-L2 on dendritic cells.

Lactic acid bacteria have potential in immunomodulation therapy, but their clinical efficacy and underlying mechanisms are unclear. We aimed to clarify the anti-allergic immune responses induced by intragastric and sublingual administration of heat-killed Lactobacillus paracasei KW3110 and Lactobacillus acidophilus L-92. The KW3110 strain (but not the L-92 strain) enhanced ovalbumin (OVA)-induced expression of CCR-7 and PD-L2 in murine dendritic cells (DCs), and strongly inhibited IL-5 and IL-13 production in vitro in co-cultures with Th2-skewed CD4(+) T cells from DO11.

Increase of regulatory T cells and the ratio of specific IgE to total IgE are candidates for response monitoring or prognostic biomarkers in 2-year sublingual immunotherapy (SLIT) for Japanese cedar pollinosis.

The aims of this study were to examine the therapeutic effects of sublingual immunotherapy (SLIT) and to identify potential biomarkers that would predict the therapeutic response in a randomized, double-blind, placebo-controlled clinical trial. The trial was carried out over two pollinosis seasons in 2007 and 2008. Carry-over therapeutic effects were analyzed in 2009.

CXCR4 expression on activated B cells is downregulated by CD63 and IL-21.

CXCR4 expression is critical for localization of centroblasts in the dark zone of germinal centers (GCs), and centrocytes downregulate CXCR4 and thus leave the dark zone to reside in the light zone. However, mechanisms governing CXCR4 downregulation on centrocytes are not known. In this study, we show that the amount of intracellular CXCR4 in centroblasts was similar to that in centrocytes, suggesting differential control of CXCR4 protein expression in these GC B cells.

Down-regulation of ICOS ligand by interaction with ICOS functions as a regulatory mechanism for immune responses.

Although it is well-known that the ICOS-ICOS ligand (ICOSL) costimulatory pathway is important for many immune responses, recent accumulated evidence suggests that dysregulation of this pathway may lead to and/or exaggerate autoimmune responses. ICOS is induced on the cell surface after T cell activation. Similarly, ICOSL is up-regulated on APCs by several mitogenic stimuli.

Plasma cell differentiation in T-independent type 2 immune responses is independent of CD11c(high) dendritic cells.

Dendritic cells (DC) play an important role as antigen-presenting cells in T cell stimulation. Interestingly, a number of recent studies also imply DC as critical accessory cells in B cell activation, isotype switching and plasma blast maintenance. Here we use the conditional in vivo ablation of CD11c(high) DC to investigate the role of these cells in T-independent type 2 immune responses.

Competence and competition: the challenge of becoming a long-lived plasma cell.

Plasma cells provide humoral immunity. They have traditionally been viewed mainly as short-lived end-stage products of B-cell differentiation that deserve little interest. This view is changing, however, because we now know that plasma cells can survive for long periods in the appropriate survival niches and that they are an independent cellular component of immunological memory.

Novel role of the Ras cascade in memory B cell response.

Engagement of the B cell antigen receptor (BCR) triggers the Ras cascade, but the biological role of the latter in B cell response is unknown. Here, we report that in T cell-dependent response, the role of the Ras cascade is confined to memory B cells and possibly marginal zone B cells. When Ras-dependent BCR signaling was impaired, the generation of IgG germinal center B cells was unaffected but the recruitment of high-affinity cells into the memory compartment and terminal differentiation were inhibited.

Two waves of memory B-cell generation in the primary immune response.

Memory B cells can be generated independently of germinal center (GC) formation and affinity maturation in Bcl-6-deficient mice, but the contribution of the GC-independent pathway for memory B-cell generation in normal mice remains unknown. To examine this, we administrated anti-inducible co-stimulator (ICOS) mAbs into mice at the onset of GC formation in the primary response. This manipulation affected the generation of GC B cells in the spleen, but neither IgG1 memory B cell nor production of IgG1 long-term antibody was affected.