Mutations in SERPINB7, Encoding a Member of the Serine Protease Inhibitor Superfamily, Cause Nagashima-type Palmoplantar Keratosis

“Nagashima-type” palmoplantar keratosis (NPPK) is an autosomal recessive nonsyndromic diffuse palmoplantar keratosis characterized by well-demarcated diffuse hyperkeratosis with redness, expanding on to the dorsal surfaces of the palms and feet and the Achilles tendon area. Hyperkeratosis in NPPK is mild and nonprogressive, differentiating NPPK clinically from Mal de Meleda. We performed whole-exome and/or Sanger sequencing analyses of 13 unrelated NPPK individuals and identified biallelic putative loss-of-function mutations in SERPINB7, which encodes a cytoplasmic member of the serine protease inhibitor superfamily. We identified a major causative mutation of c.796C>T (p.Arg266∗) as a founder mutation in Japanese and Chinese populations. SERPINB7 was specifically present in the cytoplasm of the stratum granulosum and the stratum corneum (SC) of the epidermis. All of the identified mutants are predicted to cause premature termination upstream of the reactive site, which inhibits the proteases, suggesting a complete loss of the protease inhibitory activity of SERPINB7 in NPPK skin. On exposure of NPPK lesional skin to water, we observed a whitish spongy change in the SC, suggesting enhanced water permeation into the SC due to overactivation of proteases and a resultant loss of integrity of the SC structure. These findings provide an important framework for developing pathogenesis-based therapies for NPPK

Hemodynamics in a heart with myocardial infarction and a heart with mitral regurgitation superimposed in myocardial infarction

Mitral regurgitation following myocardial infarction is one of the most serious complications. Therefore, early detection of the mitral regurgitation occurring in myocardial infarction must help in directing a treatment for it and in improving its prognosis. This study was conducted to establish a new clue of predicting mitral regurgitation complicated on myocardial infarction. Acute myocardial infarction and quantitatively measurable mitral regurgitation were made in 14 normal canine hearts to determine hemodynamics. Acute myocardial infarction was produced by ligating the anterior descending branch of the left coronary artery at its proximal one third and filling the branch distal to the ligation with 2 % -agar solution. Mitral regurgitation was through an external shunt from the apex of the left ventricle to the left atrial appendage. Hemodynamics were altered on production of myocardial infarction as follows: decrease of aortic and left ventricular pressures, increase of left atrial pressure and LVEDP, decrease of LV-max. dp/dt, and decrease of cardiac output and LV-SW. Hemodynamic alterations were as follows in a heart with mitral regurgitation superimposed on myocardial infarction. Mitral regurgitation was twice as much as cardiac output of heart with myocardial infarction: increase of left atrial pressure and LVEDP, increase of total stroke volume with decrease of effective stroke volume, increase of LV-max. dp/dt, increase of aortic and left ventricular systolic pressure. With increase of mitral regurgitation amounting 4 times as much as the cardiac output of a heart with only myocardial infarction, hemodynamics changed as follows: further decrease of effective stroke volume and LV-SW, decrease of aortic and left ventricular pressure, and no change in LV-max. dp/dt. Analysis of the aortic and left ventricular pressure tracings revealed shortening of the rapid ejection period, resulting in reduced ratio of this period to cardiac cycle. It was concluded that pressure tracing of the aorta or left ventricle would reflect hemodynamics altered when mitral regurgitation was complicated with myocardial infarction. Namely, it is conceivable that mitral regurgitation occurred in a patient with myocardial infarction when the pressure tracing showed shortening of the rapid ejection period. Therefore, monitoring of the arterial pressure tracing is available even in a less-equipped institute and yields indispensable information that mitral regurgitation did develop in a patient with myocardial infarction

Soluble immune checkpoint factors reflect exhaustion of antitumor immunity and response to PD-1 blockade.

BACKGROUNDPrecise stratification of patients with non-small cell lung cancer (NSCLC) is needed for appropriate application of PD-1/PD-L1 blockade therapy.METHODSWe measured soluble forms of the immune-checkpoint molecules PD-L1, PD-1, and CTLA-4 in plasma of patients with advanced NSCLC before PD-1/PD-L1 blockade. A prospective biomarker-finding trial (cohort A) included 50 previously treated patients who received nivolumab. A retrospective observational study was performed for patients treated with any PD-1/PD-L1 blockade therapy (cohorts B and C), cytotoxic chemotherapy (cohort D), or targeted therapy (cohort E). Plasma samples from all patients were assayed for soluble immune-checkpoint molecules with a highly sensitive chemiluminescence-based assay.RESULTSNonresponsiveness to PD-1/PD-L1 blockade therapy was associated with higher concentrations of these soluble immune factors among patients with immune-reactive (hot) tumors. Such an association was not apparent for patients treated with cytotoxic chemotherapy or targeted therapy. Integrative analysis of tumor size, PD-L1 expression in tumor tissue (tPD-L1), and gene expression in tumor tissue and peripheral CD8+ T cells revealed that high concentrations of the 3 soluble immune factors were associated with hyper or terminal exhaustion of antitumor immunity. The combination of soluble PD-L1 (sPD-L1) and sCTLA-4 efficiently discriminated responsiveness to PD-1/PD-L1 blockade among patients with immune-reactive tumors.CONCLUSIONCombinations of soluble immune factors might be able to identify patients unlikely to respond to PD-1/PD-L1 blockade as a result of terminal exhaustion of antitumor immunity. Our data suggest that such a combination better predicts, along with tPD-L1, for the response of patients with NSCLC.TRIAL REGISTRATIONUMIN000019674.FUNDINGThis study was funded by Ono Pharmaceutical Co. Ltd. and Sysmex Corporation

Flaky Tail Mouse Denotes Human Atopic Dermatitis in the Steady State and by Topical Application with Dermatophagoides pteronyssinus Extract

The barrier abnormality, a loss-of-function mutation in the gene encoding filaggrin (FLG), which is linked to the incidence of atopic dermatitis (AD), is a recently discovered but important factor in the pathogenesis of AD. Flaky tail (Flgft) mice, essentially deficient in filaggrin, have been used to investigate the role of filaggrin on AD. However, the relevancy of Flgft mice to human AD needs to be determined further. In this study, we observed the clinical manifestations of Flgft mice in the steady state and their cutaneous immune responses against external stimuli, favoring human AD. Under specific pathogen-free conditions, the majority of Flgft mice developed clinical and histological eczematous skin lesions similar to human AD with outside-to-inside skin barrier dysfunction evaluated by newly devised methods. In addition, cutaneous hapten-induced contact hypersensitivity as a model of acquired immune response and a mite extract-induced dermatitis model physiologically relevant to a human AD were enhanced in Flgft mice. These results suggest that the Flgft mouse genotype has potential as an animal model of AD corresponding with filaggrin mutation in human AD

Stress-induced production of chemokines by hair follicles regulates the trafficking of dendritic cells in skin

Langerhans cells (LCs) are epidermal dendritic cells with incompletely understood origins that associate with hair follicles for unknown reasons. Here we show that in response to external stress, mouse hair follicles recruited Gr-1(hi) monocyte-derived precursors of LCs whose epidermal entry was dependent on the chemokine receptors CCR2 and CCR6, whereas the chemokine receptor CCR8 inhibited the recruitment of LCs. Distinct hair-follicle regions had differences in their expression of ligands for CCR2 and CCR6. The isthmus expressed the chemokine CCL2; the infundibulum expressed the chemokine CCL20; and keratinocytes in the bulge produced the chemokine CCL8, which is the ligand for CCR8. Thus, distinct hair-follicle keratinocyte subpopulations promoted or inhibited repopulation with LCs via differences in chemokine production, a feature also noted in humans. Pre-LCs failed to enter hairless skin in mice or humans, which establishes hair follicles as portals for LCs