Deposition of eosinophil granule major basic protein onto microfilariae of Onchocerca volvulus in the skin of patients treated with diethylcarbamazine

Purpose. Human eosinophil major basic protein (MBP) was studied in an established organ culture model for rat corneal epithelial wound healing to elucidate further the role of the protein in vernal keratopathy. Methods. Epithelial migration rates were tested for five MBP concentrations (10, 25, 50, 100, and 200 Mg/ml MBP). Results. Significantly less epithelial migration than control (P < 0.05) was observed in all tested groups. Histologic examination revealed abnormally heaped-up leading epithelial edges in all test groups compared to the normal tapered edges in all controls. Immunofluorescence disclosed MBP deposition on deepithelialized cornea. Conclusions. These results suggest that MBP may contribute to vernal corneal ulcerations by inhibiting corneal epithelial migration. Invest Ophthalmol Vis Sci. 1994;35:3051-3056

B Cells Play Key Roles in Th2-Type Airway Immune Responses in Mice Exposed to Natural Airborne Allergens

<div><p>Humans are frequently exposed to various airborne allergens. In addition to producing antibodies, B cells participate in immune responses via various mechanisms. The roles of B cells in allergic airway inflammation and asthma have been controversial. We examined the functional importance of B cells in a mouse model of asthma, in which mice were exposed repeatedly to common airborne allergens. Naïve wild-type BALB/c mice or B cell-deficient JH^−/− mice were exposed intranasally to a cocktail of allergen extracts, including <i>Alternaria</i>, <i>Aspergillus</i>, and house dust mite, every other day for two weeks. Ovalbumin was included in the cocktail to monitor the T cell immune response. Airway inflammation, lung pathology, and airway reactivity were analyzed. The airway exposure of naïve wild type mice to airborne allergens induced robust eosinophilic airway inflammation, increased the levels of Th2 cytokines and chemokines in the lung, and increased the reactivity to inhaled methacholine. These pathological changes and immune responses were attenuated in B cell-deficient JH^−/− mice. The allergen-induced expansion of CD4⁺ T cells was impaired in the lungs and draining lymph nodes of JH^−/− mice. Furthermore, lymphocytes from JH^−/− mice failed to produce Th2 cytokines in response to ovalbumin re-stimulation <i>in vitro</i>. Our results suggest that B cells are required for the optimal development of Th2-type immune responses and airway inflammation when exposed to common airborne allergens. The therapeutic targeting of B cells may be beneficial to treat asthma in certain patients.</p></div

Th2-type responses in draining lymph nodes are attenuated in JH^-/- mice.

<p>WT or JH-^/- mice were intranasally exposed to OAAH for 2 weeks, as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0121660#pone.0121660.g001" target="_blank">Fig. 1A</a>. (A) Mediastinal lymph nodes (MLNs) were harvested, and cells were stained with anti-CD3 and anti-CD4 antibodies and analyzed by flow cytometry. Results are presented as mean±SEM (n = 5 mice per group). *, p<0.05; **, p<0.01. Data are representative of two independent experiments. (B) MLN cells were cultured with medium alone or with OVA (100 μg/ml) in 96-well tissue culture plates for 5 days. The levels of cytokines in the culture supernatants were analyzed by ELISA. *; p<0.05 between the groups indicated by horizontal lines. Data (mean±range, n = 2) are representative of three independent experiments.</p

Allergen exposure-induced airway inflammation is attenuated in B cell-deficient JH^-/- mice.

<p>(A) The experimental protocol is shown. Wild-type (WT) or JH^-/- mice were intranasally exposed to a cocktail of allergens (OAAH; ovalbumin, <i>Alternaria</i>, <i>Aspergillus</i>, house dust mite) on days 0, 2, 4, 7, 9, 11, and 14, and they were analyzed on day 15. (B) Cell differentials in BAL fluids were counted and presented as mean±standard error of the mean (SEM; n = 4 and 6 in PBS and OAAH, respectively). **, p<0.01, between WT BALB/c and JH^-/- mice exposed to OAAH. (C) Lung sections were stained with hematoxylin and eosin stains (upper and middle panels) or with the anti-mouse MBP antibody (lower panels). Original magnification, 160×. Scale bars, 50 μm. Data are representative of two independent experiments. (D) Chemokine levels in BAL fluids were determined by ELISA. Results are presented as mean±SEM (n = 4 and 6 in PBS and OAAH, respectively).</p

Airway reactivity is reduced in JH^-/- mice.

<p>WT or JH^-/- mice were intranasally exposed to OAAH or PBS for 2 weeks, as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0121660#pone.0121660.g001" target="_blank">Fig. 1A</a>. (A) Airway reactivity to inhaled methacholine was assessed by whole-body plethysmography, as described in the Methods section. Results are presented as the percentage of baseline (i.e. before PBS or methacholine challenge) and as mean±SEM (n = 4 and 6 in PBS and OAAH, respectively). *, p<0.05, between WT mice and JH^-/- mice exposed to OAAH. (B) Lung sections were stained with the periodic acid-Schiff stain. Original magnification, 160×. Scale bars, 50 μm. Data are representative of two independent experiments.</p

Th2-type cellular and humoral immune responses are decreased in JH^-/- mice.

<p>WT or JH^-/- mice were intranasally exposed to OAAH or PBS for 2 weeks, as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0121660#pone.0121660.g001" target="_blank">Fig. 1A</a>. (A) Cytokine levels in lung homogenates were determined by ELISA. (B) Blood was collected from these mice 24 hours after the last allergen exposure. The antibody levels in the plasma were analyzed by ELISA. (C) Single-cell suspensions of the lung were stained with anti-CD3 and anti-CD4 antibodies and analyzed by flow cytometry. Cell numbers were calculated based on cell counts and percentages of CD3⁺ and CD4⁺ cells. Results are presented as mean±SEM (n = 5 mice per group). *, p<0.05; **, p<0.01, between the groups indicated by horizontal lines. Data are representative of two independent experiments.</p