alpha-Defensins: DEFENSINS found in azurophilic granules of neutrophils and in the secretory granules of intestinal PANETH CELLS.Paneth Cells: Differentiated epithelial cells of the INTESTINAL MUCOSA, found in the basal part of the intestinal crypts of Lieberkuhn. Paneth cells secrete GROWTH FACTORS, digestive enzymes such as LYSOZYME and antimicrobial peptides such as cryptdins (ALPHA-DEFENSINS) into the crypt lumen.Defensins: Family of antimicrobial peptides that have been identified in humans, animals, and plants. They are thought to play a role in host defenses against infections, inflammation, wound repair, and acquired immunity.Blood Buffy Coat: The fraction of a blood sample, following CENTRIFUGATION, that is distinguished as a thin light-colored layer between the RED BLOOD CELLS, underneath it, and the PLASMA, above it. It is composed mostly of WHITE BLOOD CELLS and PLATELETS.beta-Defensins: DEFENSINS found mainly in epithelial cells.Matrix Metalloproteinase 7: The smallest member of the MATRIX METALLOPROTEINASES. It plays a role in tumor progression.Antimicrobial Cationic Peptides: Small cationic peptides that are an important component, in most species, of early innate and induced defenses against invading microbes. In animals they are found on mucosal surfaces, within phagocytic granules, and on the surface of the body. They are also found in insects and plants. Among others, this group includes the DEFENSINS, protegrins, tachyplesins, and thionins. They displace DIVALENT CATIONS from phosphate groups of MEMBRANE LIPIDS leading to disruption of the membrane.Intestine, Small: The portion of the GASTROINTESTINAL TRACT between the PYLORUS of the STOMACH and the ILEOCECAL VALVE of the LARGE INTESTINE. It is divisible into three portions: the DUODENUM, the JEJUNUM, and the ILEUM.Anti-Infective Agents: Substances that prevent infectious agents or organisms from spreading or kill infectious agents in order to prevent the spread of infection.Protein PrecursorsNeutrophils: Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.