Phagosomal Rupture by Mycobacterium tuberculosis Results in Toxicity and Host Cell Death

Survival within macrophages is a central feature of Mycobacterium tuberculosis pathogenesis. Despite significant advances in identifying new immunological parameters associated with mycobacterial disease, some basic questions on the intracellular fate of the causative agent of human tuberculosis in antigen-presenting cells are still under debate. To get novel insights into this matter, we used a single-cell fluorescence resonance energy transfer (FRET)-based method to investigate the potential cytosolic access of M. tuberculosis and the resulting cellular consequences in an unbiased, quantitative way. Analysis of thousands of THP-1 macrophages infected with selected wild-type or mutant strains of the M. tuberculosis complex unambiguously showed that M. tuberculosis induced a change in the FRET signal after 3 to 4 days of infection, indicating phagolysosomal rupture and cytosolic access. These effects were not seen for the strains M. tuberculosisΔRD1 or BCG, both lacking the ESX-1 secreted protein ESAT-6, which reportedly shows membrane-lysing properties. Complementation of these strains with the ESX-1 secretion system of M. tuberculosis restored the ability to cause phagolysosomal rupture. In addition, control experiments with the fish pathogen Mycobacterium marinum showed phagolysosomal translocation only for ESX-1 intact strains, further validating our experimental approach. Most importantly, for M. tuberculosis as well as for M. marinum we observed that phagolysosomal rupture was followed by necrotic cell death of the infected macrophages, whereas ESX-1 deletion- or truncation-mutants that remained enclosed within phagolysosomal compartments did not induce such cytotoxicity. Hence, we provide a novel mechanism how ESX-1 competent, virulent M. tuberculosis and M. marinum strains induce host cell death and thereby escape innate host defenses and favor their spread to new cells. In this respect, our results also open new research directions in relation with the extracellular localization of M. tuberculosis inside necrotic lesions that can now be tackled from a completely new perspective

Early Childhood Mental Health Consultation: A Developing Profession

As a career path, early childhood mental health consultation MHC is an emerging and growing work force opportunity. In keeping with the vision of an effective transformed service system expressed in the final report of the Presidents\u27 New Freedom Commission, and communities are expanding capacity to meet the mental health needs of young children and caregivers through mental health sultation. ECMHC supports children in naturalistic community and avoids the excessively expert tude9 and works through collaboration with families and other providers who care for them. In addition, is growing experience and research evidence to suggest that ECMHC an effective service that, from a license health perspective, promotes and emotional development and vents or reduces the impact of mental health problems in young children. The early childhood mental health consultation workforce is in transition from one of broad diversity in terms of training, experience, roles, responsibilities, and work expectations to one that has specific expertise in early childhood mental health and the specific skills required to take on the role of consultant. The purpose of this article is to support the development of a transformed workforce with the attitudes, knowledge, skills, and behaviors to work as early childhood mental health consultants in a changing children\u27s mental health field

Early Childhood Mental Health Consultation: An Evaluation Tool Kit

For states, communities, agencies and programs investing in early childhood mental health consultation and committed to quality data. This web-based resource combines a brief review of the literature and current research addressing the effectiveness of early childhood mental health consultation with guidance for designing and implementing program evaluation. It will help states, communities, and programs increase their capacity for high-quality evaluation of early childhood mental health consultation in community-based settings. Researchers, policy makers and program evaluation teams will find: A brief review of the evidence base, current issues, and questions; Defining characteristics of early childhood mental health consultation; Components of high quality evaluation and sample logic models; Evaluation tools to measure both process and outcome, including outcomes for children, families, staff and programs; and Guidance for using evaluation data for program improvement and communicating outcomes