title: A Broad-Spectrum Infection Diagnostic that Detects Pathogen-Associated Molecular Patterns (PAMPs) in Whole Blood.
abstract: BACKGROUND
  Blood cultures, and molecular diagnostic tests that directly detect pathogen DNA in blood, fail to detect bloodstream infections in most infected patients. Thus, there is a need for a rapid test that can diagnose the presence of infection to triage patients, guide therapy, and decrease the incidence of sepsis.
  
  
  METHODS
  An Enzyme-Linked Lectin-Sorbent Assay (ELLecSA) that uses magnetic microbeads coated with an engineered version of the human opsonin, Mannose Binding Lectin, containing the Fc immunoglobulin domain linked to its carbohydrate recognition domain (FcMBL) was developed to quantify pathogen-associated molecular patterns (PAMPs) in whole blood. This assay was tested in rats and pigs to explore whether it can detect infections and monitor disease progression, and in prospectively enrolled, emergency room patients with suspected sepsis. These results were also compared with data obtained from non-infected patients with or without traumatic injuries.
  
  
  RESULTS
  The FcMBL ELLecSA was able to detect PAMPS present on, or released by, 85% of clinical isolates representing 47 of 55 different pathogen species, including the most common causes of sepsis. The PAMP assay rapidly (<1h) detected the presence of active infection in animals, even when blood cultures were negative and bacteriocidal antibiotics were administered. In patients with suspected sepsis, the FcMBL ELLecSA detected infection in 55 of 67 patients with high sensitivity (>81%), specificity (>89%), and diagnostic accuracy of 0·87. It also distinguished infection from trauma-related inflammation in the same patient cohorts with a higher specificity than the clinical sepsis biomarker, C-reactive Protein.
  
  
  CONCLUSIONS
  The FcMBL ELLecSA-based PAMP assay offers a rapid, simple, sensitive and specific method for diagnosing infections, even when blood cultures are negative and antibiotic therapy has been initiated. It may help to triage patients with suspected systemic infections, and serve as a companion diagnostic to guide administration of emerging dialysis-like sepsis therapies.
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States.
authors.forename: Mark
authors.initials: M
authors.lastname: Cartwright
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States; Hôpitaux Universitaires Paris Ile de France Ouest (AP-HP), UMR INSERM U1173-UFR SSSV Université de Versailles St Quentin en Yvelines, Montigny, France.
authors.forename: Martin
authors.initials: M
authors.lastname: Rottman
authors.affiliation: Department of Emergency Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, United States.
authors.forename: Nathan I
authors.initials: NI
authors.lastname: Shapiro
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Seiler
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States.
authors.forename: Patrick
authors.initials: P
authors.lastname: Lombardo
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States.
authors.forename: Nazita
authors.initials: N
authors.lastname: Gamini
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States.
authors.forename: Julie
authors.initials: J
authors.lastname: Tomolonis
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States.
authors.forename: Alexander L
authors.initials: AL
authors.lastname: Watters
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States.
authors.forename: Anna
authors.initials: A
authors.lastname: Waterhouse
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States.
authors.forename: Dan
authors.initials: D
authors.lastname: Leslie
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States.
authors.forename: Dana
authors.initials: D
authors.lastname: Bolgen
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States.
authors.forename: Amanda
authors.initials: A
authors.lastname: Graveline
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States.
authors.forename: Joo H
authors.initials: JH
authors.lastname: Kang
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States.
authors.forename: Tohid
authors.initials: T
authors.lastname: Didar
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States.
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Dimitrakakis
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States.
authors.forename: David
authors.initials: D
authors.lastname: Cartwright
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States.
authors.forename: Michael
authors.initials: M
authors.lastname: Super
authors.affiliation: Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, United States; Vascular Biology Program, Boston Children's Hospital and Harvard Medical School, Boston, MA, United States; Harvard John A. Paulson School of Engineering and Applied Sciences, Cambridge, MA, United States. Electronic address: don.ingber@wyss.harvard.edu.
authors.forename: Donald E
authors.initials: DE
authors.lastname: Ingber
mesh_terms: D000368:Aged; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use; D019540:Area Under Curve; D001419:Bacteria / Q000187:drug effects / Q000378:metabolism* / Q000472:pathogenicity; D002097:C-Reactive Protein / Q000032:analysis; D004195:Disease Models, Animal; D004797:Enzyme-Linked Immunosorbent Assay; D004926:Escherichia coli / Q000187:drug effects / Q000378:metabolism / Q000472:pathogenicity; D005260:Female; D006801:Humans; D007118:Immunoassay; D037102:Lectins / Q000737:chemistry / Q000378:metabolism; D008070:Lipopolysaccharides / Q000378:metabolism; D008297:Male; D058619:Maltose-Binding Proteins / Q000737:chemistry / Q000378:metabolism; D008875:Middle Aged; D000069452:Pathogen-Associated Molecular Pattern Molecules / Q000097:blood*; D012372:ROC Curve; D051381:Rats; D017208:Rats, Wistar; D012680:Sensitivity and Specificity; D018805:Sepsis / Q000175:diagnosis* / Q000188:drug therapy; D013552:Swine
chemical_list: D000900:Anti-Bacterial Agents; D037102:Lectins; D008070:Lipopolysaccharides; D058619:Maltose-Binding Proteins; D000069452:Pathogen-Associated Molecular Pattern Molecules; D002097:C-Reactive Protein
keywords: Biomarker; Blood culture; C-reactive protein; Infection diagnostic; Mannose binding lectin; Sepsis