Low doses of IgG from atopic individuals can modulatein vitroIFN-γ production by human intra-thymic TCD4 and TCD8 cells: An IVIg comparative approach

Abstract

The regulatory effect of allergic responses induced by IgG antibodies on human intra-thymic cells has not been reported in the literature. The aim of this study was to evaluate the possible differential effect of purified IgG from atopic and non-atopic individuals on human intra-thymic αβT cell cytokine production. Thymic tissues were obtained from 14 patients who were less than 7 d old. Additionally, blood samples were collected from atopic and non-atopic volunteers. Thymocytes and peripheral blood mononuclear cells were cultured with purified atopic or non-atopic IgG, and intracellular cytokine production was assessed. Purified IgG did not influence the frequency or viability of human intra-thymic αβT cells. Purified non-atopic IgG induced greater IFN-γ production by intra-thymic CD4+CD8+ T cells than did the mock treatment and atopic IgG. A similar effect of purified non-atopic IgG on TCD8 cells was observed compared with the mock treatment. Atopic IgG inhibited IFN-γ and TGF-β production by intra-thymic TCD4 cells. Treatment with intravenous immunoglobulin resulted in intermediate levels of IFN-γ and TGF-β in intra-thymic TCD4 cells compared with treatment with atopic and non-atopic IgG. Peripheral TCD4 cells from non-atopic individuals produced IFN-γ only in response to atopic IgG. This report describes novel evidence revealing that IgG from atopic individuals may influence intracellular IFN-γ production by intra-thymic αβT cells in a manner that may favor allergy development.

Maternal IgG impairs the maturation of offspring intrathymic IL‐17‐producing γδT cells: Implications for murine and human allergies

“…IgG was purified from pooled serum according to the specifications of the Melon Gel IgG Spin Purification Kit (Thermo) and as previously described . Purified IgG was collected, sterilized and stored at −80°C for use in cell culture experiments.…”

“…IgG was purified from pooled serum according to the specifications of the Melon Gel IgG Spin Purification Kit (Thermo) and as previously described. 3,35 Purified IgG was collected, sterilized and stored at −80°C for use in cell culture experiments. IgG concentrations were determined using Coomassie Protein Assay Reagent (Pierce) according to the manufacturer's instructions.…”

IgG from atopic dermatitis patients induces non‐atopic infant thymic invariant natural killer T (iNKT) cells to produce IL‐4, IL‐17, and IL‐10

“…The SPTs were performed in accordance with European standards with an adapted panel of allergens that included the profile of Brazilian allergens (i.e., Dermatophagoide farinae, Dermatophagoides Pteronyssimus, Blomia tropicalis, Gallus gallus domesticus, Litopenaeus vannamei, Farfanepenaeus subtilis , Farfanepenaeus paulensis, Sus scrofa domesticus, Bertholletia excels, Arachis hypogaea, Aspergillus fulmigatus, Penicillium notatum, Alternaria Alternata, Cladosporium herbarum, Blatella germânica, Periplaneta Americana, Avena nativa, Hordeum vulgare, Tricicum aestivum, Gallus gallus domesticus, Solenopsisi invicta, Culex pipiens, Canis familiaris Felis domesticus and Bos Taurus ) as described previously by our group, and we excluded the results for patients who used antihistamines, glucocorticosteroids, or certain other systemic drugs that can influence the SPT results within 15 days before the test. We also excluded volunteers with severe eczema or dermographism.…”

IgG from atopic dermatitis patients induces IL‐17 and IL‐10 production in infant intrathymic TCD4 and TCD8 cells

“…IgG was purified from pooled serum according to the specifications of the Melon Gel IgG Spin Purification Kit (Thermo, Waltham, USA) and as recently described . Briefly, a purification gel was transferred to a column coupled to a polypropylene conical tube and was then centrifuged.…”

“…Recently, our group demonstrated that human purified IgG from atopic individuals influences the cytokine production profile of human intrathymic αβ T cells in vitro ; moreover, such an influence of IgG upon lymphocytes during the maturation process was not entirely dependent on the maternal origin of IgG. Our next step was to evaluate whether the IgG repertoire from AD patients correlates with cytokine modulation, thus favoring eczematous lesions.…”