Basophils are rapidly mobilized following initial aeroallergen encounter in naïve mice and provide a priming source of IL-4 in adaptive immune responses.

Chronic aeroallergen inhalation elicits the expansion of IL-4-producing Th2 cells and the production of IgE antibodies. In sensitized subjects, who have established IgE and Th2 responses, re-exposure to allergen leads to rapid recruitment of basophils, which are thought to be important effectors of late phase allergic reactions. Several investigations of responses to parasites and injected antigens have identified an additional role for basophils as innate immune effectors during initial antigen encounter in immunologically naïve hosts. These cells constitutively express IL-4 and promote Th2 polarized adaptive responses to such antigens. Their early recruitment and modulation of cellular immune responses to natural inhaled allergens in the airways has been scarcely investigated. In this study, basophils were enumerated in lung tissue, blood and spleen from BALB/c mice in the first days after inhalation of an aqueous extract of the allergen, Aspergillus fumigatus (Af). Af inhalation induced rapid increases in basophil numbers in the lung, blood and spleen. This was Rag-1-, MyD88- and IL-3-independent. The basophils expressed abundant IL-4. Their depletion during Af sensitization resulted in an attenuated induction of both IL-4 producing Th lymphocytes and specific IgE and IgG1 responses to an inhaled protein antigen, ovalbumin, which was co-administered. Our results suggest that basophils are rapidly recruited to the airways of naïve mice following initial fungal allergen exposure, produce IL-4 and influence the development of the adaptive immune response.

Health seeking behavior among cancer patients attending Ocean Road Cancer Institute; Tanzania

Objectives: To characterize cancer patients and to determine the associated health seeking behaviours. Methods: Between September 2005 and February 2006; we collected data using structured and semi-structured interviews among new cancer patients attending the ORCI. Findings are summarized using univarite and bivariate analyses. Results: There were 330 cancer patients during the study period. The mean age was 48 (SD = 13.5) years ranging between 21 and 84 years. The majority; 205 (62.1); were females. More than two thirds of all patients; that is 225 (68.2); presented at the ORCI at advanced stages of disease. Many patients reported to have neither heard; 193 (58.5); nor to know cancer symptoms; 203 (61.5). Only 185 (56.1) of all patients reported their willingness to disclose and a freedom to talk about the disease. Risk factors for cancer staging were sex; patient's education status; awareness and knowledge of disease symptoms. Conclusions: Interventions targeted to improve health care seeking behaviour among cancer patients need to include health education and sensitization specifically of cancer disease; establish a strong referral mechanisms at primary health level and to start a population cancer registry for monitoring and evaluation purposes