Gland Tissue Sections Research Articles

In-situ hybridization localized MUC7 mucin gene expression to the mucous acinar cells of human and MUC7-transgenic mouse salivary glands.

MUC7 gene that encodes the low molecular weight human salivary mucin MG2, was previously shown to be expressed in tissue-specific manner in normal human salivary glands and in salivary glands of transgenic mice carrying the MUC7 transgene. The purpose of this study was to examine the cell specificity of MUC7 expression in human and transgenic mice salivary glands. To localize the MUC7 transcripts, we used in-situ hybridization in combination with Tyramide Signal Amplification procedure. The results clearly showed that in both the human and transgenic mice salivary gland tissue sections, MUC7 transcripts were localized only in mucous acinar cells; no signals were found in serous acinar cells or any other cell types present in these salivary glands.

Characterization of Antinuclear Autoantibodies Present in the Serum from Nonobese Diabetic (NOD) Mice

The nonobese diabetic (NOD) mouse develops insulin-dependent type 1 diabetes in response to autoantibodies and T-cell attack directed against pancreatic islet cell antigens. Sera obtained from nondiabetic and diabetic female mice demonstrated a 1.4-fold increase in IgG levels when compared to BALB/c control animals. Nondiabetic and diabetic male mice had a 2.1- and 3-fold increase, respectively, in serum IgG levels over that of control mice. Seven of 11 nondiabetic and 7/10 diabetic sera from female NOD mice contained antibody to cytoplasmic or nuclear components of HEp-2 cells. Cytoplasmic staining revealed reaction against cytoskeletal and midbody structures. Punctate nuclear staining patterns with HEp-2 cells showed antibody reaction to the centriole, mitotic chromosomes, and nuclear rim. On the other hand, sera from BALB/c mice were negative for antibody staining of HEp-2 cells. Confirmation of the autoantibody nature of the NOD sera was obtained by antibody staining of nuclear structures from the mouse 3T3 fibroblast cell line, and by staining of salivary gland tissue sections. The nuclear and cytoplasmic staining patterns of diabetic NOD sera were reminiscent of the autoantibody staining patterns observed in Sjögren's syndrome and other inflammatory autoimmune connective tissue diseases.

Bursectomy of chicken embryos at 60 hours of incubation leads to an oligoclonal B cell compartment and restricted Ig diversity.

Chickens that have been surgically bursectomized at 60 h of embryonic development usually generate Ig producing B cells; however, the bursectomized chickens are incapable of specific antibody responses, even after repeated immunization. In the present work, we analyzed the molecular basis of this immunodeficiency. In the bursectomized chickens, DNA sequencing revealed a repertoire of Ig L and H chains with a low number of different V-J and V-D-J joints, indicating an oligoclonal B cell compartment. In addition, the L and H chains belonging to each B cell clone had similar gene conversion events in the V region. In situ hybridization to Harderian gland tissue sections showed, that B cells of the bursectomized chickens were, however, capable of terminal plasma cell maturation. Thus, in chickens that were lacking the bursal microenvironment, 1) only a few B cell precursors differentiated into mature Ig-producing B cells, 2) low rate of gene conversion resulted in restricted Ig diversity. Regarding the chicken B cell differentiation, the present data support a model that the induction of B cell differentiation is a bursa-independent event, whereas the bursa of Fabricius has a crucial role in the amplification and diversification of the embryonic B cell repertoire.

Immunological characterization of mononuclear cells in thyroid gland and blood in Graves' disease, multinodular goiter and papillary carcinoma.

Mononuclear cell infiltrates in thyroid gland tissue sections from patients with drug-treated Graves' disease (n = 5), non-toxic nodular goiter (n = 12) and papillary carcinoma (n = 5) were characterized by immunological membrane receptors. T lymphocytes were identified using 2-aminoethylisothiouronium bromide hydrobromide (AET)-treated sheep erythrocytes (E) (E-AET). E sensitized with rabbit IgM antibodies (A) and human complement (C) (EAC) were used to detect receptors for C3b (B lymphocytes and monocytes) or C3d (B lymphocytes). E sensitized with rabbit IgG antibodies were used to detect receptors for the Fc portion of IgG (FcR; lymphocytes and monocytes). The results indicate that T and B lymphocytes infiltrate the thyroid gland in Graves' disease as well as in nodular goiter. T lymphocytes seemed to predominate in both disorders. In thyroid papillary carcinoma the number of B and T lymphocytes was negligible. However, EA absorbed strongly to sections from 3 of the 5 tumors studied, indicating the presence of FcR on tumor cells or infiltrating host cells. The percentage of active and total T lymphocytes in peripheral blood from the patients with drug-treated Graves' disease was markedly reduced (9 +/- 5 and 28 +/- 11%, controls 22 +/- 9 and 68 +/- 11%; p less than 0.01 and less than 0.001). In patients with nodular goiter the percentage of total T lymphocytes was slightly, but significantly decreased (p less than 0.05). We suggest that the marked decrease in blood T lymphocytes observed in Graves' disease might be caused by the drug therapy. In nodular goiter the predominance of T lymphocyte infiltration together with a slight decrease in blood T lymphocytes suggest that autoimmune mechanisms are involved in the pathogenesis.

Identification of phaeopigments in the digestive gland of Mytilus edulis L. by microspectrofluorimetry

Epi-illuminated fluorescence microscopy was used to observe chlorophyll degradation products localized in lipid spherules within the digestive gland of Mytilus edulis L. These fluorescing materials, known collectively as phaeopigments, then were spectrally analysed in situ with a microspectrofluorimeter. The results were compared with acetone extracts of the digestive gland and chlorophyll a standard solutions. Emission wavelength peaks were 671.2 nm for chlorophyll a in 85% acetone, and 672.8 nm for the acidified chlorophyll a solution, 66.3 nm for digestive gland extracts in 85% acetone, and 677.1 nm for phaeopigment in tissue sections. Acid factors of 1.0 for digestive gland extracts and tissue sections confirmed the red fluorescing material to be phaeopigment. Quantities up to 167 ng for an 11-μm diameter lipid spherule were encountered. Results were compared with calculated concentrations of phaeopigment determined spectrophotometrically.