Biomaterial Database

Identification of acid cysteine proteinase inhibitor (cystatin A) in the human thymus. 1994

K O Söderström, and R Rinne, and V K Hopsu-Havu, and M Järvinen, and A Rinne

Department of Pathology, University of Finland, Turku.

BACKGROUND Acid cysteine proteinase inhibitor (ACPI, also called cystatin A) is a protein that is present in the epithelial cells of the skin and in the dendritic reticulum cells of lymphoid tissues. In this study the presence and cellular localization of ACPI in the thymus was investigated. METHODS The cellular and topographical location of ACPI was immunohistochemically demonstrated in the normal thymus of man. RESULTS ACPI was found in the cells of the Hassall's corpuscles and in many medullary cells. Most of these cells were epithelial cells, as shown by the results of immunohistochemical cytokeratin and epithelial membrane antigen stainings. Also, some individual cytokeratin negative but S-100 positive medullary reticular dendritic cells were stained with ACPI. CONCLUSIONS The finding that ACPI is constantly present in the thymus at restricted and specific cellular locations leads to the suggestion that protease inhibitors may play a role in specific thymic functions.

UI	MeSH Term	Description	Entries
D007150	Immunohistochemistry	Histochemical localization of immunoreactive substances using labeled antibodies as reagents.	Immunocytochemistry,Immunogold Techniques,Immunogold-Silver Techniques,Immunohistocytochemistry,Immunolabeling Techniques,Immunogold Technics,Immunogold-Silver Technics,Immunolabeling Technics,Immunogold Silver Technics,Immunogold Silver Techniques,Immunogold Technic,Immunogold Technique,Immunogold-Silver Technic,Immunogold-Silver Technique,Immunolabeling Technic,Immunolabeling Technique,Technic, Immunogold,Technic, Immunogold-Silver,Technic, Immunolabeling,Technics, Immunogold,Technics, Immunogold-Silver,Technics, Immunolabeling,Technique, Immunogold,Technique, Immunogold-Silver,Technique, Immunolabeling,Techniques, Immunogold,Techniques, Immunogold-Silver,Techniques, Immunolabeling
D007633	Keratins	A class of fibrous proteins or scleroproteins that represents the principal constituent of EPIDERMIS; HAIR; NAILS; horny tissues, and the organic matrix of tooth ENAMEL. Two major conformational groups have been characterized, alpha-keratin, whose peptide backbone forms a coiled-coil alpha helical structure consisting of TYPE I KERATIN and a TYPE II KERATIN, and beta-keratin, whose backbone forms a zigzag or pleated sheet structure. alpha-Keratins have been classified into at least 20 subtypes. In addition multiple isoforms of subtypes have been found which may be due to GENE DUPLICATION.	Cytokeratin,Keratin Associated Protein,Keratin,Keratin-Associated Proteins,alpha-Keratin,Associated Protein, Keratin,Keratin Associated Proteins,Protein, Keratin Associated,alpha Keratin
D008214	Lymphocytes	White blood cells formed in the body's lymphoid tissue. The nucleus is round or ovoid with coarse, irregularly clumped chromatin while the cytoplasm is typically pale blue with azurophilic (if any) granules. Most lymphocytes can be classified as either T or B (with subpopulations of each), or NATURAL KILLER CELLS.	Lymphoid Cells,Cell, Lymphoid,Cells, Lymphoid,Lymphocyte,Lymphoid Cell
D009418	S100 Proteins	A family of highly acidic calcium-binding proteins found in large concentration in the brain and believed to be glial in origin. They are also found in other organs in the body. They have in common the EF-hand motif (EF HAND MOTIFS) found on a number of calcium binding proteins. The name of this family derives from the property of being soluble in a 100% saturated ammonium sulfate solution.	Antigen S 100,Nerve Tissue Protein S 100,S100 Protein,S-100 Protein,S100 Protein Family,Protein, S100,S 100 Protein
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000906	Antibodies	Immunoglobulin molecules having a specific amino acid sequence by virtue of which they interact only with the ANTIGEN (or a very similar shape) that induced their synthesis in cells of the lymphoid series (especially PLASMA CELLS).
D013950	Thymus Gland	A single, unpaired primary lymphoid organ situated in the MEDIASTINUM, extending superiorly into the neck to the lower edge of the THYROID GLAND and inferiorly to the fourth costal cartilage. It is necessary for normal development of immunologic function early in life. By puberty, it begins to involute and much of the tissue is replaced by fat.	Thymus,Gland, Thymus,Glands, Thymus,Thymus Glands
D015891	Cystatins	A homologous group of endogenous CYSTEINE PROTEINASE INHIBITORS. The cystatins inhibit most CYSTEINE ENDOPEPTIDASES such as PAPAIN, and other peptidases which have a sulfhydryl group at the active site.	Cystatin,Cystatin Superfamily,Stefin,Cystatin-Related Proteins,Stefins,Type 1 Cystatins,Type 2 Cystatins,Type 3 Cystatins,Type I Cystatins,Type II Cystatins,Type III Cystatins,Cystatin Related Proteins,Cystatins, Type 1,Cystatins, Type 2,Cystatins, Type 3,Cystatins, Type I,Cystatins, Type II,Cystatins, Type III