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It is not clear whether pseudoallergic reactions are caused by similar mechanisms as type I allergic reactions. 3-Caffeoylquinic acid (chlorogenic acid) is an active ingredient in traditional Chinese medicines used for antibacterial, anti-inflammatory and cholagogic purposes. It is assumed to be the reason for the high allergic reaction rates associated with certain traditional Chinese medicine injection solutions. The aim of the present study was to investigate the possible mechanisms through which chlorogenic acid triggers pseudoallergic reactions. The fluidity of the cell membrane was investigated using fluorescence recovery after photobleaching. Western blot analysis was used to measure the phosphorylation levels of the Spleen tyrosine kinase (Syk) protein and Fluo-3/AM fluorescent probes were used to investigate the influx of calcium ions. In addition, fluorescence microscopy and phalloidin were used to determine F-actin depolymerization levels. The secretion rate of β-hexosaminidase by RBL-2H3 cells clearly increased following treatment with chlorogenic acid and the levels of cytoskeletal disintegration were also markedly increased. Furthermore, we detected an increase in the intracellular calcium ion concentration along with distinct changes in Syk protein phosphorylation and cellular F-actin. These changes indicated that chlorogenic acid affected the restructuring of the cytoskeleton and played a role in cell degranulation. In conclusion, chlorogenic acid may lead to the aggregation of lipid rafts on the cell membrane surface by altering RBL-2H3 cell membrane fluidity, thus triggering Syk-related signal transduction and inducing a truncated type I like allergic reaction.

AimsThe essential role of basophils as an initiator of chronic allergic reaction has been elucidated in mouse models. The aim of this present study was to analyse the in situ immunolocalisation of basophils and other relevant inflammatory cells in chronic allergic keratoconjunctivitis.MethodsTransmission electron microscopic (TEM) analysis was carried out to examine the existence of basophils in the giant papillae obtained from atopic keratoconjunctivitis (AKC) and vernal keratoconjunctivitis (VKC) patients. Cryostat sections of giant papillae were immunostained with basophil-specific antibody BB-1, and with anti-CD4, anti-CD8, anti-CD20, anti-major basic protein (MBP), anti-IgE and anti-FcɛRI-β antibodies.ResultsTEM analysis confirmed the existence of basophils in the giant papillae. Small clusters of basophils were observed in the substantia propria of giant papillae, especially at the vicinity of vascular endothelium and subepithelial regions. BB-1-positive basophil clusters were surrounded by T cells, B cells, IgE-positive cells and MBP-positive eosinophils. No BB-1-positive basophils were observed in the control conjunctivae.ConclusionBasophils may infiltrate from either vascular endothelium into the giant papillae. The existence of basophils at the centre of inflammatory cells suggests the role of basophils as an initiator of chronic allergic conjunctivitis.

The biological action of ultra high dilutions is controversial. Inhibition of anti-IgE induced basophil degranulation by successive histamine dilutions is of interest, as it studies a chemically defined compound (histamine) which exerts a negative feed back effect via the histamine H sub(2) receptor. The biological activity is measured using the human basophil degranulation test, which is relatively simple to perform and does not require specialised equipment. Inhibition of basophil degranulation was observed with histamine dilutions ranging between the 15 super(th) and 19 super(th) centesimal dilutions. Since most data were originally obtained from only one laboratory, this study aimed to verify these results in a multi-centre trial.

Splenic and bone marrow cells from normal mice, and from mice that have been polyclonally activated by injection of anti-IgD antibody, contain cells that produce interleukin 4 (IL-4) in response to crosslinkage of Fcεreceptors (FcεR) or FcγR or to ionomycin. Isolated FcεR+cells have recently been shown to contain all of the IL-4-producing capacity of the nonlymphoid compartment of spleen and bone marrow. Here, purified FcεR+cells are shown to be enriched in cells that contain histamine and express alcian blue-positive cytoplasmic granules. By electron microscopy, the vast majority of cytoplasmic granule-containing cells are basophils; they constitute ≈25% and ≈50%, respectively, of FcεR+spleen and bone marrow cells from anti-IgD-injected mice. The FcεR-populations contain cells that form colonies typical of mast cells. The FcεR+populations also contain cells that, upon culture with IL-3, form colonies of alcian blue-positive cells, but (in contrast to colonies derived from FcεR-populations) the colonies are small, and all the cells die within 2-3 weeks. The FcεR+cells synthesize histamine during a 60-hr culture with IL-3, while the FcεR-cells do not. These results indicate that IL-4-producing FcεR+cells are highly enriched in basophils.

Dichloroacetic acid (DCA) is carcinogenic to the B6C3F(1) mouse and the F344 rat. Given the carcinogenic potential of DCA in rodent liver and the known concentrations of this compound in drinking water, reliable biologically based models to reduce the uncertainty of risk assessment for human exposure to DCA are needed. Development of such models requires identification and quantification of premalignant hepatic lesions, identification of the doses at which these lesions occur, and determination of the likelihood that these lesions will progress to cancer. In this study we determined the dose response of histopathologic changes occurring in the livers of mice exposed to DCA (0.05-3.5 g/L) for 26-100 weeks. Lesions were classified as foci of cellular alteration smaller than one liver lobule (altered hepatic foci; AHF), foci of cellular alteration larger than one liver lobule (large foci of cellular alteration; LFCA), adenomas (ADs), or carcinomas (CAs). Histopathologic analysis of 598 premalignant lesions revealed that (a)) each lesion class had a predominant phenotype; (b)) AHF, LFCA, and AD demonstrated neoplastic progression with time; and (c)) independent of DCA dose and length of exposure effects, some toxic/adaptive changes in non-involved liver were related to this neoplastic progression. A lesion sequence for carcinogenesis in male B6C3F(1) mouse liver has been proposed that will enable development of a biologically based mathematical model for DCA. Because all classes of premalignant lesions and CAs were found at both lower and higher doses, these data are consistent with the conclusion that nongenotoxic mechanisms, such as negative selection, are relevant to DCA carcinogenesis at lower doses where DCA genotoxicity has not been observed.

Basophilic leucocytes are metachromatic granule-containing secretory granulocytes that contain a mixture of granular proteoglycans devoid of heparin. In guinea pigs, isolated basophilic leucocyte granules primarily contain chondroitin sulphate. We have recently demonstrated that an enzyme-affinity- gold technique to image RNA, using the reagent RNase gold, also binds specifically to heparin in human mast cell granules. Such binding is based on the known property of heparin as a competitive inhibitor of RNase. Using similar methods, we show here that RNase-gold binds to the chondroitin sulphate in the secretory granules of guinea pig basophils, thus broadening the applicability of this post-embedding affinity-gold method to studies that require imaging of chondroitin sulphate in routinely prepared electron microscopical samples.[PUBLICATION ABSTRACT]

This study characterized the cell population recovered by respiratory-tract lavage of 57 two-week-old and 59 six-week-old specific-pathogen-free chickens as a prerequisite to study the response of the avian respiratory tract to infectious agents. The respiratory tract of each bird was lavaged through the trachea with a series of three lavages of 10 ml of room-temperature, neutral phosphate-buffered saline per lavage. The three lavages per bird were pooled for analysis. Total recovery volumes were measured, lavage fluid cellularity was determined, and a 200-cell differential count of non-erythrocyte cells was performed. Lavage fluid recovery was greater from 2-week-old birds (91.3 percent) than from 6-week-old birds (86.3 percent). Total cells recovered were greater for 6-week-old chickens (6.79 × 105) than for 2-week-old chickens (5.03 × 105). Cells of epithelial origin included squamous cells, goblet cells, and both ciliated and non-ciliated columnar epithelial cells. Cells of non-epithelial origin consisted of heterophils, lymphocytes, macrophages, eosinophils, basophils, and erythrocytes. Cells of epithelial origin were the predominant cell type recovered from the 2-week-old chickens, followed by heterophils. In 6-week-old chickens, heterophils were the predominant cell type recovered, followed by cells of epithelial origin. In descending order of prevalence, the remainder of cell types recovered from chickens of both ages were lymphocytes, macrophages, eosinophils, and basophils. /// Como un prerequisito para estudiar la respuesta del tracto respiratorio aviar a agentes infecciosos, se caracterizó la población celular recolectada por medio del lavado del tracto respiratorio de 57 pollos de dos semanas de edad y de 59 pollos de seis semanas, libres de patógenos específicos. Al tracto respiratorio de cada ave se le practicó una serie de tres lavados, usando 10 ml de solución salina tamponada-fosfatada neutra mantenida a temperatura ambiente. Los tres lavados por ave fueron recolectados y analizados conjuntamente. Se midió el volumen total obtenido, se determinó el tipo de células en el lavado y se realizó un recuento diferencial de 200 células no eritrocíticas. El fluido recolectado por los lavados fue mayor en las aves de 2 semanas de edad (91.3%) que en las aves de 6 semanas de edad (86.3%). El número total de células obtenido fue mayor en los pollos de 6 semanas (6.79 × 105) que en los de 2 semanas (5.03 × 105). Las células de origen epitelial incluyeron células escamosas, células caliciformes y células de epitelio columnar ciliadas y no ciliadas. Las células de origen no epitelial consistieron en heterófilos, linfocitos, macrófagos, eosinófilos, basófilos y eritrocitos. Las células de origen epitelial fueron el tipo predominante dentro de lo recolectado en los pollos de 2 semanas de edad, seguido por los heterófilos. En los pollos de 6 semanas de edad, los heterófilos fueron predominantes, seguidos por las células de origen epitelial. En orden descendiente de prevalencia, el resto de las células recolectadas en pollos de ambas edades fueron linfocitos, macrófagos, eosinófilos, y basófilos.