Novel Serial Positive Enrichment Technology Enables Clinical Multiparameter Cell Sorting

A general obstacle for clinical cell preparations is limited purity, which causes variability in the quality and potency of cell products and might be responsible for negative side effects due to unwanted contaminants. Highly pure populations can be obtained best using positive selection techniques. However, in many cases target cell populations need to be segregated from other cells by combinations of multiple markers, which is still difficult to achieve – especially for clinical cell products. Therefore, we have generated low-affinity antibody-derived Fab-fragments, which stain like parental antibodies when multimerized via Strep-tag and Strep-Tactin, but can subsequently be removed entirely from the target cell population. Such reagents can be generated for virtually any antigen and can be used for sequential positive enrichment steps via paramagnetic beads. First protocols for multiparameter enrichment of two clinically relevant cell populations, CD4high/CD25high/CD45RAhigh ‘regulatory T cells’ and CD8high/CD62Lhigh/CD45RAneg ‘central memory T cells’, have been established to determine quality and efficacy parameters of this novel technology, which should have broad applicability for clinical cell sorting as well as basic research

A dynamic course of T cell defects in individuals at risk for mood disorders

Objectives: T cell abnormalities have been repeatedly reported in adult patients with mood disorders, suggesting a role of these cells in the pathogenesis of these disorders. In the present study, we explored the dynamics of circulating T cell subsets over time in a population at high familial risk for developing a mood disorder. Methods: Children of a parent with bipolar disorder (bipolar offspring, N = 140) were assessed at three time-points: adolescence, young adulthood and adulthood. We carried out a detailed fluorescence activated cell sorting (FACS) analysis to determine various T cell subsets from frozen stored peripheral blood mononuclear cells of bipolar offspring and age- and gender-matched healthy controls at each time-point. Results: Throughout the period of observation reduced levels of CD3+ and CD3+ CD4+ T cells were observed. In bipolar offspring T(h)1, T(h)2, T(h)17 and natural T regulatory cells (T-regs) followed a dynamic course over time with reduced levels of T, in adolescence and a reduced relative number of T(h)1, T(h)17 cells in young adulthood. In post hoc analysis T-regs were inversely associated with the pro inflammatory monocyte state determined previously (r(s)=-0.220, p = 0.001). Significant associations between T cell subset abnormalities and psychopathology such as mood disorders were not found. Conclusions: A subtle partial T cell defect was present in bipolar offspring from adolescence through adulthood. Within this defect the dynamic change of inflammatory and regulatory T cell subsets suggests a high inflammatory state during adolescence, a reduced inflammatory state during young adulthood and a virtually normalized state at adulthood. (C) 2016 Elsevier Inc. All rights reserved

A dynamic course of T cell defects in individuals at risk for mood disorders

OBJECTIVES: T cell abnormalities have been repeatedly reported in adult patients with mood disorders, suggesting a role of these cells in the pathogenesis of these disorders. In the present study, we explored the dynamics of circulating T cell subsets over time in a population at high familial risk for developing a mood disorder. METHODS: Children of a parent with bipolar disorder (bipolar offspring, N=140) were assessed at three time-points: adolescence, young adulthood and adulthood. We carried out a detailed fluorescence-activated cell sorting (FACS) analysis to determine various T cell subsets from frozen stored peripheral blood mononuclear cells of bipolar offspring and age- and gender-matched healthy controls at each time-point. RESULTS: Throughout the period of observation reduced levels of CD3+ and CD3+ CD4+ T cells were observed. In bipolar offspring Th1, Th2, Th17 and natural T regulatory cells (Tregs) followed a dynamic course over time with reduced levels of Tregs in adolescence and a reduced relative number of Th1, Th17 cells in young adulthood. In post-hoc analysis Tregs were inversely associated with the pro-inflammatory monocyte state determined previously (rs=-.220, p=.001). Significant associations between T cell subset abnormalities and psychopathology such as mood disorders were not found. CONCLUSIONS: A subtle partial T cell defect was present in bipolar offspring from adolescence through adulthood. Within this defect the dynamic change of inflammatory and regulatory T cell subsets suggests a high inflammatory state during adolescence, a reduced inflammatory state during young adulthood and a virtually normalized state at adulthood