concanavalin-a and Rodent-Diseases

A lectin histochemical study was carried out on the dorsal skin of Wistar-derived hypotrichotic WBN/Ila-Ht rats (HtRs) and Wistar rats (WRs) at 3, 7 and 24 weeks of age to clarify the lectinhistochemical characteristics of the skin during their development. The lectins examined were Concanavalia ensiformis (Con A), Dolichos biflorus agglutinin (DBA), Griffonia simpliciolia (GS-I), Helix pomatia agglutinin (HPA), Arachis hypogaea (PNA), Glycine maximus agglutinin (SBA), Ulex europeus agglutinin (UEA-I) and Triticum vulgaris agglutinin (WGA). None of the nucleated cell layers of the epidermis had DBA-binding sites, but they were all stained intensely with HPA and weakly with Con A irrespective of the strain and age of the rats. As to the other 5 lectins, the intensity of binding activity was generally weaker in HtRs than in WRs and at 3 weeks of age than at 7 or 24 weeks of age, respectively. Among them, UEA-I mainly bound to the spinous cell layer but not to the basal cell layer, suggesting that alpha-L-fucose would be expressed on the cell surface according to the differentiation of keratinocytes. In addition, GS-I, HPA and UEA-I bound to the hair follicle epithelium and many lectins stained sebaceous gland epithelial cells. In conclusion, except for the binding intensity of some lectins, there were no specific differences between HtRs and Wrs in the lectinhistochemical characteristics of the dorsal skin epidermis. The present data on the rat skin would be useful from the viewpoint of comparative lectinhistochemistry.

Topics: Animals; Concanavalin A; Histocytochemistry; Hypotrichosis; Lectins; Male; Plant Lectins; Rats; Rats, Inbred Strains; Rats, Wistar; Rodent Diseases; Skin

Long-Evans (Eker) rats carry a mutation that predisposes them to develop spontaneous renal cell tumors of two morphologic patterns: solid chromophilic masses or cystic lesions lined by eosinophilic cells. Previous studies have suggested that these tumors arise from the proximal tubules. In the present study, lectin-binding characteristics and cytokeratin expression of various stages of hereditary rat renal epithelial neoplasia were examined to localize the portion of the nephron from which tumors arise. Lectin-binding histochemistry has been used as a marker of cell surface glycoprotein expression, thought to be important in the differentiation of benign from malignant epithelial lesions and in the determination of their cell of origin. The presence or absence of keratin intermediate filaments in the rat nephron has been used to identify nephron segments. The polyclonal antibody to high- and low-molecular-weight cytokeratin stained the cells of the collecting ducts but not the proximal or distal tubules. Binding to the proximal tubules by the lectins Conavalia ensiformis (Con A), Dolichas biflorus, Ricinus communis (RCA-1), and Triticum vulgare and to the distal tubules by Con A, RCA-1, Arachis hypogaea (PNA) with and without neuraminidase, and the antibody for cytokeratins was demonstrated. The lectin binding and cytokeratin staining patterns of rat hereditary renal cell carcinoma, adenoma and the preneoplastic lesions of atypical tubules and hyperplasias suggest that cystic adenomas arise from the distal nephron, principally the collecting duct, whereas the solid atypical tubules, hyperplasias, and adenomas arise from the proximal nephron, principally the proximal tubule.

Topics: Adenoma; Animals; Biomarkers, Tumor; Carcinoma, Renal Cell; Concanavalin A; Histocytochemistry; Hyperplasia; Immunohistochemistry; Keratins; Kidney Neoplasms; Kidney Tubules, Distal; Kidney Tubules, Proximal; Lectins; Male; Plant Lectins; Precancerous Conditions; Rats; Rodent Diseases; Wheat Germ Agglutinins

Topics: Animals; Choristoma; Concanavalin A; Female; Galactose Oxidase; Intestines; Mucous Membrane; Rats; Rats, Inbred F344; Rats, Inbred Strains; Rodent Diseases; S100 Proteins; Stomach Neoplasms

In the course of experimental BCG infection in mice, cytotoxic autoantibodies (CAA) of IgM class reacting with thymocytes and T lymphocytes were found. CAA were not cytotoxic for bone marrow cells and B lymphocytes. CAA reacts with PNA+, glass wool-adherent, hydrocortisone-sensitive thymocytes. The reaction of thymocytes with CAA and complement, prevented suppressor cell induction from such treated cells. The importance of CAA in mycobacterial infection is discussed.

Topics: Animals; Autoantibodies; Concanavalin A; Cytotoxicity, Immunologic; Epitopes; Immunoglobulin M; Mice; Mice, Inbred Strains; Rodent Diseases; T-Lymphocytes; Tuberculosis

The criteria for selecting and establishing a animal model for arthritis were described. Rats are the most frequently used animals. Adjuvant and Myocobacterium induced arthritis provide a model of chronic joint inflammation, although significant differences exist when compared with human disease. A better model of arthritis in rats and mice can be induced by the injection of one strain of Mycoplasma arthritidis. An even better model is presented by rabbits first immunized against a protein such as heterologous fibrin or albumin, and then challenged by the same protein injected directly into a joint. This results in a localized chronic arthritis pathologically similar to that of man. Arithritis can also be induced in rabbits by the injection of polymers such as chitinor or Concanavalin A into the joint. Although there is no lack of arthritis animal models, there is no animal model which gives a true replication of rheumatoid arthritis.

Topics: Animals; Arthritis; Arthritis, Infectious; Arthritis, Rheumatoid; Concanavalin A; Disease Models, Animal; Dog Diseases; Dogs; Haplorhini; Mice; Mycobacterium; Mycobacterium tuberculosis; Mycoplasma Infections; Rabbits; Rats; Rodent Diseases