Skin homeostasis is maintained by the continuous proliferation and differentiation of epidermal cells. The skin forms a strong but flexible barrier against microorganisms as well as physical and chemical insults; however, the physiological mechanisms that maintain this barrier are not fully understood. Here, we have described a mutant mouse that spontaneously develops pruritic dermatitis as the result of an initial defect in skin homeostasis that is followed by induction of a Th2-biased immune response. These mice harbor a mutation that results in a single aa substitution in the JAK1 tyrosine kinase that results in hyperactivation, thereby leading to skin serine protease overexpression and disruption of skin barrier function. Accordingly, treatment with an ointment to maintain normal skin barrier function protected mutant mice from dermatitis onset. Pharmacological inhibition of JAK1 also delayed disease onset. Together, these findings indicate that JAK1-mediated signaling cascades in skin regulate the expression of proteases associated with the maintenance of skin barrier function and demonstrate that perturbation of these pathways can lead to the development of spontaneous pruritic dermatitis.
Takuwa Yasuda, Toshiyuki Fukada, Keigo Nishida, Manabu Nakayama, Masashi Matsuda, Ikuo Miura, Teruki Dainichi, Shinji Fukuda, Kenji Kabashima, Shinji Nakaoka, Bum-Ho Bin, Masato Kubo, Hiroshi Ohno, Takanori Hasegawa, Osamu Ohara, Haruhiko Koseki, Shigeharu Wakana, Hisahiro Yoshida
The rare patients who are able to spontaneously control HIV replication in the absence of therapy show signs of a particularly efficient cellular immune response. To identify the molecular determinants that underlie this response, we characterized the T cell receptor (TCR) repertoire directed at Gag293, the most immunoprevalent CD4 epitope in the HIV-1 capsid. HIV controllers from the ANRS CODEX cohort showed a highly skewed TCR repertoire that was characterized by a predominance of
Daniela Benati, Moran Galperin, Olivier Lambotte, Stéphanie Gras, Annick Lim, Madhura Mukhopadhyay, Alexandre Nouël, Kristy-Anne Campbell, Brigitte Lemercier, Mathieu Claireaux, Samia Hendou, Pierre Lechat, Pierre de Truchis, Faroudy Boufassa, Jamie Rossjohn, Jean-François Delfraissy, Fernando Arenzana-Seisdedos, Lisa A. Chakrabarti
Autism spectrum disorder (ASD) is an increasingly common behavioral condition that frequently presents with gastrointestinal (GI) disturbances. It is not clear, however, how gut dysfunction relates to core ASD features. Multiple, rare hyperfunctional coding variants of the serotonin (5-HT) transporter (SERT, encoded by
Kara Gross Margolis, Zhishan Li, Korey Stevanovic, Virginia Saurman, Narek Israelyan, George M. Anderson, Isaac Snyder, Jeremy Veenstra-VanderWeele, Randy D. Blakely, Michael D. Gershon
IFN-γ is a critical mediator of host defense against
Andreas Kupz, Ulrike Zedler, Manuela Stäber, Carolina Perdomo, Anca Dorhoi, Roland Brosch, Stefan H.E. Kaufmann
Cameron J. Turtle, Laïla-Aïcha Hanafi, Carolina Berger, Theodore A. Gooley, Sindhu Cherian, Michael Hudecek, Daniel Sommermeyer, Katherine Melville, Barbara Pender, Tanya M. Budiarto, Emily Robinson, Natalia N. Steevens, Colette Chaney, Lorinda Soma, Xueyan Chen, Cecilia Yeung, Brent Wood, Daniel Li, Jianhong Cao, Shelly Heimfeld, Michael C. Jensen, Stanley R. Riddell, David G. Maloney
A eubiotic microbiota influences many physiological processes in the metazoan host, including development and intestinal homeostasis. Here, we have shown that the intestinal microbiota modulates inflammatory responses caused by sex steroid deficiency, leading to trabecular bone loss. In murine models, sex steroid deficiency increased gut permeability, expanded Th17 cells, and upregulated the osteoclastogenic cytokines TNFα (TNF), RANKL, and IL-17 in the small intestine and the BM. In germ-free (GF) mice, sex steroid deficiency failed to increase osteoclastogenic cytokine production, stimulate bone resorption, and cause trabecular bone loss, demonstrating that the gut microbiota is central in sex steroid deficiency–induced trabecular bone loss. Furthermore, we demonstrated that twice-weekly treatment of sex steroid–deficient mice with the probiotics
Jau-Yi Li, Benoit Chassaing, Abdul Malik Tyagi, Chiara Vaccaro, Tao Luo, Jonathan Adams, Trevor M. Darby, M. Neale Weitzmann, Jennifer G. Mulle, Andrew T. Gewirtz, Rheinallt M. Jones, Roberto Pacifici
In this issue of the
Jameel Iqbal, Tony Yuen, Li Sun, Mone Zaidi
The cover image is a density-dependent color scanning electron micrograph of a calcified human carotid artery atherosclerotic plaque, with dense, calcified areas shown in orange and less dense components of the plaque shown in green. On page 1323, Goettsch et al. report that sortilin regulates vascular calcification that is mediated by extracellular vesicle release. Image credit: Sergio Bertazzo.
JCI This Month is a digest of the research, reviews, and other features published each month.
Pediatric neurologist Huda Zoghbi, HHMI investigator at the Baylor College of Medicine and director of the Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, has used genetic and biochemical approaches to elucidate the mechanisms of spinocerebellar ataxia and Rett syndrome.
Cell-to-cell communication is an essential component in multicellular organisms, allowing for rapid, coordinated responses to changes within the environment. Classical signaling mediators include direct cell-cell contact as well as secreted factors, such as cytokines, metabolites, and hormones. In the past decade, extracellular vesicles (EVs), including exosomes, microvesicles, and apoptotic bodies, have emerged as important mediators of intercellular communication. EVs are double-membrane vesicles containing cargoes of multiple proteins, lipids, and nucleic acids, which are derived from their cells of origin, and EV cargoes can change depending on the status of their originating cells. Importantly, EVs are found in all body fluids and can carry their cargoes to distant sites within the body as well as neighboring cells. Reviews in this series discuss the role of EV-mediated signaling in physiological and pathophysiological conditions, including infection, host immune responses, and cancer. Additionally, these reviews cover the potential clinical use of EVs as therapeutics and diagnostic biomarkers.