title: The salivary scavenger and agglutinin in early life: diverse roles in amniotic fluid and in the infant intestine.
abstract: The salivary scavenger and agglutinin (SALSA), also known as gp340 and dmbt1, is an antimicrobial and inflammation-regulating molecule located at the mucosal surfaces. The present study revealed that SALSA was present in the amniotic fluid (AF) and exceptionally enriched in both meconium and feces of infants. Based on immunological and mass spectrometric analysis, SALSA was estimated to constitute up to 4-10% of the total protein amount in meconium, making it one of the most abundant proteins. SALSA proteins in the AF and intestinal samples were polymorphic and exhibited varying polypeptide compositions. In particular, a different abundance of peptides corresponding to functionally important structures was found in the AF and intestinal SALSA. The AF form of SALSA had a more intact structure and contained peptides from the zona pellucida domain, which is involved in cell differentiation and oligomerization. In contrast, the intestinal SALSA was more enriched with the scavenger receptor cysteine-rich domains. The AF, but not the meconium SALSA, bound to Streptococcus pyogenes, S. agalactiae, S. gordonii, and Escherichia coli. Furthermore, differential binding was observed also to known endogenous ligands C1q, mannose-binding lectin, and secretory IgA. Our results have thus identified mucosal body compartments, where SALSA is particularly abundant, and suggest that SALSA exhibits varying functions in the different mucosal locations. The high levels of SALSA in AF and the infant intestine suggest a robust and important function for SALSA during the fetal development and in the mucosal innate immune defense of infants.
authors.affiliation: Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Helsinki FI-00014, Finland; Immunobiology Research Program, Research Programs Unit, University of Helsinki, Helsinki FI-00014, Finland;
authors.forename: Martin Parnov
authors.initials: MP
authors.lastname: Reichhardt
authors.affiliation: Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Helsinki FI-00014, Finland; Immunobiology Research Program, Research Programs Unit, University of Helsinki, Helsinki FI-00014, Finland; Helsinki University Central Hospital Laboratory, Helsinki FI-00029, Finland;
authors.forename: Hanna
authors.initials: H
authors.lastname: Jarva
authors.affiliation: Department of Veterinary Biosciences, University of Helsinki, Helsinki FI-00014, Finland; Department of Medical Microbiology, University Medical Center Utrecht, Utrecht 2584 CX, the Netherlands;
authors.forename: Mark
authors.initials: M
authors.lastname: de Been
authors.affiliation: Department of Nutrition, Food Science and Food Technology, Complutense University of Madrid, Madrid 28040, Spain;
authors.forename: Juan Miguel
authors.initials: JM
authors.lastname: Rodriguez
authors.affiliation: Department of Nutrition, Food Science and Food Technology, Complutense University of Madrid, Madrid 28040, Spain;
authors.forename: Esther
authors.initials: E
authors.lastname: Jimenez Quintana
authors.affiliation: Department of Medical Biochemistry and Genetics, University of Turku, Turku FI-20014, Finland; and.
authors.forename: Vuokko
authors.initials: V
authors.lastname: Loimaranta
authors.affiliation: Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Helsinki FI-00014, Finland; Department of Medical Microbiology, University Medical Center Utrecht, Utrecht 2584 CX, the Netherlands; Laboratory of Microbiology, Wageningen University, Wageningen 6708 PB, the Netherlands.
authors.forename: Willem Meindert
authors.initials: WM
authors.lastname: de Vos
authors.affiliation: Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Helsinki FI-00014, Finland; Immunobiology Research Program, Research Programs Unit, University of Helsinki, Helsinki FI-00014, Finland; Helsinki University Central Hospital Laboratory, Helsinki FI-00029, Finland; seppo.meri@helsinki.fi.
authors.forename: Seppo
authors.initials: S
authors.lastname: Meri
mesh_terms: D000595:Amino Acid Sequence; D000653:Amniotic Fluid / Q000737:chemistry / Q000276:immunology*; D002135:Calcium-Binding Proteins; D015922:Complement C1q / Q000276:immunology / Q000378:metabolism; D004268:DNA-Binding Proteins; D004926:Escherichia coli / Q000737:chemistry / Q000276:immunology; D015870:Gene Expression; D006801:Humans; D018928:Immunity, Mucosal; D007070:Immunoglobulin A / Q000276:immunology / Q000378:metabolism; D007231:Infant, Newborn; D007422:Intestines / Q000737:chemistry / Q000276:immunology*; D037601:Mannose-Binding Lectin / Q000276:immunology / Q000378:metabolism; D008470:Meconium / Q000737:chemistry / Q000276:immunology; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009928:Organ Specificity; D010446:Peptide Fragments / Q000737:chemistry*; D010449:Peptide Mapping; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011956:Receptors, Cell Surface / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism; D013291:Streptococcus / Q000737:chemistry / Q000276:immunology; D025521:Tumor Suppressor Proteins
chemical_list: D002135:Calcium-Binding Proteins; C108174:DMBT1 protein, human; D004268:DNA-Binding Proteins; D007070:Immunoglobulin A; D037601:Mannose-Binding Lectin; D010446:Peptide Fragments; D011956:Receptors, Cell Surface; D025521:Tumor Suppressor Proteins; D015922:Complement C1q