Investigation of inflammatory and allergic responses to common mold species: Results from in vitro experiments, from a mouse model of asthma, and from a group of asthmatic patients

Most studies on molds focus on Alternaria alternata and Aspergillus fumigatus. Here, we report on inflammatory and allergenic properties of more typical indoor species Aspergillus versicolor, P. chrysogenum, C. cladosporioïdes, and C. sphaerospermum that were compared to A. alternata and A. fumigatus. In a mouse model, after intranasal instillation, A. alternaria, A. versicolor, and C. sphaerospermum induced the early recruitment of neutrophils and the strong expression of inflammatory markers in the bronchoalveolar lavages fluids. A. fumigatus also induced the early accumulation of neutrophils but with lower levels of inflammatory markers. Chronic treatment induced variable response according to species: P. chrysogenum and A. fumigatus appeared strong pro-allergenic inducers compared to A. alternata and C. sphaerospermum while A. versicolor and C. cladosporioides induced a mixed pro-allergenic/pro-inflammatory response. In mold-sensitized asthmatics, mold-specific Immunoglobulin E (IgE) were detected with an in-house dot-blot assay. A. fumigatus and A. alternata were the most frequent sensitizers. Altogether, P. chrysogenum, P. brevicompactum, C. sphaerospermum, and C. cladosporïoides were the “major sensitizer” (defined as the strongest response against a single mold species) for almost 30% of the asthmatics. These results show that, not only A. alternata and A. fumigatus, but also indoor species have strong inflammatory and allergic properties and a harmful potency.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Serum Soluble HLA-E in Melanoma: A New Potential Immune-Related Marker in Cancer

International audienceBackground: Tumor-derived soluble factors, including soluble HLA molecules, can contribute to cancer immune escape and therefore impact on clinical course of malignant diseases. We previously reported that melanoma cells produce, in vitro, soluble forms of the non-classical MHC class I molecule HLA-E (sHLA-E). In order to investigate sHLA-E production by various tumors and to address its potential value as a tumor-associated marker, we developed a specific ELISA for the quantification of sHLA-E in biological fluids. Methodology/Principal Findings: We developed a sHLA-E specific and sensitive ELISA and we showed that serum sHLA-E levels were significantly elevated (P,0.01) in melanoma patients (n = 127), compared with healthy donors (n = 94). sHLA-E was also detected in the culture supernatants of a wide variety of tumor cell lines (n = 98) including melanomas, kidney, colorectal and breast cancers. Cytokines regulation of sHLA-E production by tumor cells was also carried out. IFN-c, IFN-a and TNF-a were found to upregulate sHLA-E production by tumor cells. Conclusions/Significance: In view of the broad tumor tissue release of HLA-E and its up-regulation by inflammatory cytokines, sHLA-E should be studied for its involvement in immune responses against tumors. Interestingly, our results demonstrated a positive association between the presence of serum sHLA-E and melanoma. Therefore, the determination of sHLA-E levels, using ELISA approach, may be investigated as a clinical marker in cancer patients

Influence of cytokines on sHLA-E production by tumor cells.

<p>A/ sHLA-E detection in supernatants of three tumor cell lines: two melanoma cell lines (M88 and M102) and one colocarcinoma cell line (HT29), treated or not with IFN-α, IFN-γ or TNF-α (10 ng/ml, 48 h). Significant differences between the control and treatment values are indicated (*p<0.05, **p<0.01, ***p<0.001). B/ sHLA-E detection in culture supernatants of M102 treated with serial concentrations of IFN-α, IFN-γ and TNF-α for 48 h. C/ Time course of sHLA-E production in culture supernatant of M102 treated for up to 6 days with 10 ng/ml IFN-γ.</p

Sensitivity and specificity of sHLA-E ELISA.

<p>A/ Detection of sHLA-E using serial dilutions of recombinant HLA-E monomer. The grey area indicates the range of measurable sHLA-E levels. B/ Determination of the HLA-E binding specificity. Serial dilutions of HLA-A2, -A23, -B7, -B8 and -B27 recombinant soluble monomers have been tested in comparison with recombinant HLA-E monomer.</p

Analysis of sHLA-E production by tumor cell lines.

<p>Analysis of soluble HLA-E concentrations in supernatants of tumor cell lines treated or not by IFN-γ with regard of tumor origins: distribution of individual concentrations (A), mean levels (B) and percentages of positive supernatants (sHLA-E≥5 pg/ml) (C).</p

Characteristics of healthy donors and melanoma patients studied.

<p>Characteristics of healthy donors and melanoma patients studied.</p

Analysis of sHLA-E in sera of healthy controls and melanoma patients.

<p>A/ Illustrative detection of sHLA-E using serial dilutions of two serum samples by ELISA. B/ Distribution of soluble HLA-E concentrations in sera of healthy controls and melanoma patients. P-value indicates the difference between the two groups. C/ Percentages of positive sHLA-E sera (sHLA-E≥5 pg/ml) in healthy donors and melanoma patients. D/ Distribution of soluble HLA-E concentrations in sera of melanoma patients with regard of tumor stages.</p

Protein crystallization promotes type 2 immunity and is reversible by antibody treatment

Although spontaneous protein crystallization is a rare event in vivo, Charcot-Leyden crystals (CLCs) consisting of galectin-10 (Gal10) protein are frequently observed in eosinophilic diseases, such as asthma. We found that CLCs derived from patients showed crystal packing and Gal10 structure identical to those of Gal10 crystals grown in vitro. When administered to the airways, crystalline Gal10 stimulated innate and adaptive immunity and acted as a type 2 adjuvant. By contrast, a soluble Gal10 mutein was inert. Antibodies directed against key epitopes of the CLC crystallization interface dissolved preexisting CLCs in patient-derived mucus within hours and reversed crystal-driven inflammation, goblet-cell metaplasia, immunoglobulin E (IgE) synthesis, and bronchial hyperreactivity (BHR) in a humanized mouse model of asthma. Thus, protein crystals may promote hallmark features of asthma and are targetable by crystal-dissolving antibodies