Person: Matute, Juan
Loading...
Email Address
AA Acceptance Date
Birth Date
Research Projects
Organizational Units
Job Title
Last Name
Matute
First Name
Juan
Name
Matute, Juan
Search Results
Now showing 1 - 2 of 2
Publication Human alkaline phosphatase dephosphorylates microbial products and is elevated in preterm neonates with a history of late-onset sepsis(Public Library of Science, 2017) Pettengill, Matthew; Matute, Juan; Tresenriter, Megan; Hibbert, Julie; Burgner, David; Richmond, Peter; Luis Millán, José; Ozonoff, Alexander; Strunk, Tobias; Currie, Andrew; Levy, OferBackground: A host defense function for Alkaline phosphatases (ALPs) is suggested by the contribution of intestinal ALP to detoxifying bacterial lipopolysaccharide (endotoxin) in animal models in vivo and the elevation of ALP activity following treatment of human cells with inflammatory stimuli in vitro. However the activity of ALP in human plasma (primarily tissue-nonspecific ALP; TNAP) on lipopolysaccharide and other microbial products has not been assessed, nor has its expression been studied in preterm newborns, a vulnerable population at high risk of sepsis. In this context, the aim of our study was to characterize the activity of TNAP on Toll-like receptor (TLR) agonists and assess the concentrations of plasma ALP during late-onset sepsis in preterm newborns. Methods: Recombinant human TNAP was incubated with microbial products and phosphate release was measured by malachite green assay. Plasma ALP activity was measured serially in a cohort of preterm (N = 129) infants at high risk of late-onset sepsis (LOS). Results: TNAP dephosphorylates poly-inosine:cytosine (Toll-like receptor (TLR) 3 agonist) and LPS from Klebsiella pneumoniae and Salmonella minnesota (TLR4 agonists). Plasma ALP significantly increased postnatally over the first 4 weeks of life in preterm and term newborns. Bacteremic LOS in preterm infants (gestational age ≤ 30 weeks) was associated with significantly elevated plasma ALP at 4 weeks postnatal age. Conclusions: TNAP, the main circulating isozyme of ALP, de-phosphorylates TLR agonists, demonstrates a post-natal age dependent increase in preterm and term plasma across the first 4 weeks of life, and is elevated in association with preterm LOS.Publication Intestinal epithelial cell endoplasmic reticulum stress promotes MULT1 up-regulation and NKG2D-mediated inflammation(The Rockefeller University Press, 2017) Hosomi, Shuhei; Grootjans, Joep; Tschurtschenthaler, Markus; Krupka, Niklas; Matute, Juan; Flak, Magdalena B.; Martinez-Naves, Eduardo; Gomez del Moral, Manuel; Glickman, Jonathan N.; Ohira, Mizuki; Lanier, Lewis L.; Kaser, Arthur; Blumberg, RichardEndoplasmic reticulum (ER) stress is commonly observed in intestinal epithelial cells (IECs) and can, if excessive, cause spontaneous intestinal inflammation as shown by mice with IEC-specific deletion of X-box–binding protein 1 (Xbp1), an unfolded protein response–related transcription factor. In this study, Xbp1 deletion in the epithelium (Xbp1ΔIEC) is shown to cause increased expression of natural killer group 2 member D (NKG2D) ligand (NKG2DL) mouse UL16-binding protein (ULBP)–like transcript 1 and its human orthologue cytomegalovirus ULBP via ER stress–related transcription factor C/EBP homology protein. Increased NKG2DL expression on mouse IECs is associated with increased numbers of intraepithelial NKG2D-expressing group 1 innate lymphoid cells (ILCs; NK cells or ILC1). Blockade of NKG2D suppresses cytolysis against ER-stressed epithelial cells in vitro and spontaneous enteritis in vivo. Pharmacological depletion of NK1.1+ cells also significantly improved enteritis, whereas enteritis was not ameliorated in Recombinase activating gene 1−/−;Xbp1ΔIEC mice. These experiments reveal innate immune sensing of ER stress in IECs as an important mechanism of intestinal inflammation.