Bone marrow mesenchymal stromal cells (BM-MSCs) from healthy donors and auto-immune disease patients reduce the proliferation of autologous- and allogeneic-stimulated lymphocytes in vitro.

International audienceOBJECTIVES: To investigate the ability of bone marrow (BM)-derived mesenchymal stromal cells (BM-MSCs) in suppressing the proliferation of stimulated lymphocytes across a range of conditions including autologous BM-MSCs derived from autoimmune disease (AD) patients. METHODS: In vitro cultures of BM-MSCs from healthy donors and AD patients were established and characterized by their differentiation potential into adipocytes and osteoblasts, and their fibroblast-colony-forming unit (CFU-F) ability and phenotype by flow cytometry. BM-MSCs (irradiated and non-irradiated) from healthy and AD patients were tested for their ability to suppress the in vitro proliferation of autologous and allogeneic peripheral blood mononuclear cells (PBMC) (from healthy donors and patients suffering from various ADs) stimulated with anti-CD3epsilon antibody alone or in combination with anti-CD28 antibody. The anti-proliferative effect of the BM-MSCs from healthy donors was tested also on transformed B-cell lines as a model of non-antigen-stimulated lymphocytes. RESULTS: BM-MSCs from healthy donors and AD patients reduced the proliferation of autologous and allogeneic PBMCs by up to 90% in a cell dose-dependent fashion. The immunosuppression was independent of the proliferation of the BM-MSCs and was also effective on already proliferating cells. It was independent also of the clinical activity of AD. An MSC dose-dependent pattern of suppression of proliferation was observed also with transformed B-cell lines, similar to that observed with proliferating PBMC. CONCLUSIONS: The BM-MSCs exhibit extensive anti-proliferative properties against lymphocytes under different conditions. This property might offer a form of immunomodulatory cellular therapy for AD patients if further confirmed in animal models

Low immunoglobulin E flags two distinct types of immune dysregulation

During the last two decades, hyper-immunoglobulin (Ig)E syndromes have been characterized clinically and molecularly in patients with genetically determined primary immunodeficiencies. However, the detection of low IgE levels, defined here as below detection limit in the routine clinical immunology laboratory, has received little attention. We analysed the association of serum IgA, IgM and IgG levels (including IgG subclasses) with low, normal or high serum IgE levels in patients evaluated in a single-centre out-patient immunodeficiency and allergy clinic. The correlation of serum IgE levels with IgG subclasses depended on the clinical phenotype. In patients with immunodeficiencies, IgE correlated with IgG2 and IgG4 but not with IgG3. In contrast, in patients referred for signs of allergy, IgE correlated with IgG3 but not with IgG2. A low IgE result was associated with low IgG3 and IgG4 in allergy referrals, while immunodeficiency referrals with a low IgE result had significantly lower IgG1, IgG2 and IgG4 levels. Hierarchical clustering of non-IgE immunoglobulin profiles (IgM, IgA, IgG, IgG1-4) validated that non-IgE immunoglobulin levels predict the clinic referral, i.e. phenotype, of low-IgE patients. These results suggesto guide the clinical management of patients with low serum IgE levels

Scoring of dual fluorescein and ICG inflammatory angiographic signs for the grading of posterior segment inflammation (dual fluorescein and ICG angiographic scoring system for uveitis).

Purpose To propose a semiquantitative dual fluorescein angiography (FA) and indocyanine green angiography (ICGA) scoring system for uveitis that would assist in the follow-up of disease progression and monitoring response to treatment. Methods The scoring system was based on the FA scoring systems, the standardized ICGA protocol, and schematic interpretation of ICGA findings in posterior uveitis that have been previously published. We assigned scores to the fluorescein and ICG angiographic signs that represent ongoing inflammatory process in the posterior segment. We rated each angiographic sign according to the impact it has on our appreciation of active intraocular inflammation. In order to permit direct comparison between FA and ICGA, we multiplied the total ICGA score by a coefficient of 2 to adjust to the total score of FA. Results A total maximum score of 40 was assigned to the FA signs, including optic disc hyperfluorescence, macular edema, retinal vascular staining and/or leakage, capillary leakage, retinal capillary nonperfusion, neovascularization of the optic disc, neovascularization elsewhere, pinpoint leaks, and retinal staining and/or subretinal pooling. A total maximum score of 20 was assigned to the ICGA signs, including early stromal vessel hyperfluorescence, choroidal vasculitis, dark dots or areas (excluding atrophy), and optic disc hyperfluorescence. Conclusion The combined fluorescein and ICG angiographic scoring system proposed herein may help estimate the magnitude of retinal versus choroidal inflammation, monitor disease progression and response to treatment, and provide comparable data for clinical studies. The applicability of the proposed system needs to be tested in clinical settings, and intra- and interobserver variations need to be determined. © 2008 Springer Science+Business Media B.V