Impact of particulate air pollutants on allergic diseases, allergic skin reactivity and lung function.

Elevated levels of particulate matter can exacerbate existing asthma and atopy, while evidence that it can promote the induction of atopy and asthma is limited. A cross sectional study was taken to compare the prevalence of eye, nose, ear and airway allergic symptoms, allergic skin sensitivity and lung function in 290 high school students with a history of high 24 hour average exposure to particulate matter less than 10 microm in diameter (PM10) = 170 microg/m3 versus low PM10 of 36 microg/m3 in central Bangkok. Multivariate analysis revealed an increased risk of eye and airway symptoms in groups exposed to higher PM10 levels (p = 0.

Mast cells express connexins on their cytoplasmic membrane.

Background: Because of the close association between mast cells and fibroblasts in the microenvironment and the importance of connexins (Cxs) in fibroblast communication with other cells, we hypothesized that mast cells also express Cxs, allowing them to similarly communicate with other cells through gap junctions.

Objectives: We sought to identify the expression of Cxs (particularly Cx43, Cx32, and Cx26) by murine mast cells.

Methods: The expression of Cxs was studied by RT-PCR, Northern blot analysis, Western blot analysis, flow cytometry, and confocal laser scanning microscopy.

Identification and categorization of inducible mast cell genes in a subtraction library.

Mast cells play an important role in allergic inflammation by releasing inducible proinflammatory cytokines. While many inducible genes have been identified, we hypothesized that a significant number remain to be identified. We thus constructed an activation-specific mast cell subtraction library to establish a profile of induced genes in mast cells following allergic stimulation.

Human mast cells produce the CD4+ T lymphocyte chemoattractant factor, IL-16.

CD4+ T cell infiltration is known to occur in tissues at sites of mast cell activation. The molecules produced and released by mast cells that account for this lymphocyte accumulation are poorly characterized. Here we report that a CD4+ T cell chemoattractant cytokine, IL-16, is stored preformed in bone marrow-cultured human mast cells and a human mast cell line, HMC-1, as demonstrated by intracytoplasmic cytokine staining and flow cytometry, and in human lung mast cells, as detected by immunohistochemistry.