Boston Children's Hospital

About: Boston Children's Hospital is a healthcare organization based out in Boston, Massachusetts, United States. It is known for research contribution in the topics: Population & Transplantation. The organization has 165409 authors who have published 215589 publications receiving 6885627 citations.

Calcineurin/NFAT Coupling Participates in Pathological, but not Physiological, Cardiac Hypertrophy

Abstract: Calcineurin (PP2B) is a calcium/calmodulin-activated, serine-threonine phosphatase that transmits signals to the nucleus through the dephosphorylation and translocation of nuclear factor of activated T cell (NFAT) transcription factors. Whereas calcineurin-NFAT signaling has been implicated in regulating the hypertrophic growth of the myocardium, considerable controversy persists as to its role in maintaining versus initiating hypertrophy, its role in pathological versus physiological hypertrophy, and its role in heart failure. To address these issues, NFAT-luciferase reporter transgenic mice were generated and characterized. These mice showed robust and calcineurin-specific activation in the heart that was inhibited with cyclosporin A. In the adult heart, NFAT-luciferase activity was upregulated in a delayed, but sustained manner throughout eight weeks of pathological cardiac hypertrophy induced by pressure-overload, or more dramatically following myocardial infarction-induced heart failure. In contrast, physiological hypertrophy as produced in two separate models of exercise training failed to show significant calcineurin-NFAT coupling in the heart at multiple time points, despite measurable increases in heart to body weight ratios. Moreover, stimulation of hypertrophy with growth hormone-insulin-like growth factor-1 (GH-IGF-1) failed to activate calcineurin-NFAT signaling in the heart or in culture, despite hypertrophy, activation of Akt, and activation of p70 S6K. Calcineurin Abeta gene-targeted mice also showed a normal hypertrophic response after GH-IGF-1 infusion. Lastly, exercise- or GH-IGF-1-induced cardiac growth failed to show induction of hypertrophic marker gene expression compared with pressure-overloaded animals. Although a direct cause-and-effect relationship between NFAT-luciferase activity and pathological hypertrophy was not proven here, our results support the hypothesis that separable signaling pathways regulate pathological versus physiological hypertrophic growth of the myocardium, with calcineurin-NFAT potentially serving a regulatory role that is more specialized for maladaptive hypertrophy and heart failure.

Chimeric receptors with 4-1BB signaling capacity provoke potent cytotoxicity against acute lymphoblastic leukemia

Abstract: To develop a therapy for drug-resistant B-lineage acute lymphoblastic leukemia (ALL), we transduced T lymphocytes with anti-CD19 chimeric receptors, consisting of an anti-CD19 single-chain variable domain (reactive with most ALL cases), the hinge and transmembrane domains of CD8α, and the signaling domain of CD3ζ. We compared the antileukemic activity mediated by a novel receptor (‘anti-CD19-BB-ζ’) containing the signaling domain of 4-1BB (CD137; a crucial molecule for T-cell antitumor activity) to that of a receptor lacking costimulatory molecules. Retroviral transduction produced efficient and durable receptor expression in human T cells. Lymphocytes expressing anti-CD19-BB-ζ receptors exerted powerful and specific cytotoxicity against ALL cells, which was superior to that of lymphocytes with receptors lacking 4-1BB. Anti-CD19-BB-ζ lymphocytes were remarkably effective in cocultures with bone marrow mesenchymal cells, and against leukemic cells from patients with drug-resistant ALL: as few as 1% anti-CD19-BB-ζ-transduced T cells eliminated most ALL cells within 5 days. These cells also expanded and produced interleukin-2 in response to ALL cells at much higher rates than those of lymphocytes expressing equivalent receptors lacking 4-1BB. We conclude that anti-CD19 chimeric receptors containing 4-1BB are a powerful new tool for T-cell therapy of B-lineage ALL and other CD19+ B-lymphoid malignancies.

Mindfulness in Medicine

Abstract: the profession’s code of ethics and is personally damaging to that individual. In a controversial psychobiography of President George W. Bush, Frank, a psychiatrist, characterized the president as a “paranoid megalomaniac” and “untreated alcoholic.” Although these are clearly clinical and diagnostic labels that appear to violate the Goldwater Rule, Frank’s view is that his book is a scholarly psychobiography, not “expert opinion” and, as such, is outside the purview of APA ethics guideline. Still, the line between a careful psychiatric profile and a casual off-the-cuff diagnosis of a public figure is not so clear. Even if the intent of the mental health professional in both situations is very different—understanding the psychology of the person (psychobiography) or assailing the character of a disliked political candidate (the Goldwater case)— both share a similar ethical problem: unauthorized psychiatric assessment of a person who is not examined by the professional.