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Biomedical subjects

R R Tubbs

Publications and source records attributed to R R Tubbs.

At least 163 records · Page 9Linked to original sources

Pulmonary vasculitis (Wegener's granulomatosis). Immunohistochemical study of T and B cell markers.

A case of pulmonary vasculitis (Wegener's granulomatosis) is reported in which immunoperoxidase studies demonstrated that the vascular lymphoid infiltrates were composed predominantly of T cells and monocytes. Occasional T cells, B cells and monocytes were identified in the alveolar septa. IgG, IgA, IgM, and C3 were not identified in pulmonary vessels, septa, or alveoli. These findings suggest that cellular rather than humoral-immune mechanisms predominate in pulmonary vasculitis.

B-Lymphocytes↗

Immunohistologic cellular phenotypes of lymphoproliferative disorders. Comprehensive evaluation of 564 cases including 257 non-Hodgkin's lymphomas classified by the International Working Formulation.

The plethora of classifications for non-Hodgkin's lymphomas (NHLs) and controversy regarding the merits of the individual classification schemes has led to the articulation of an International Working Formulation for NHL classification by a working group sponsored by the National Cancer Institute. This classification is based on both architectural and cytologic features and has been shown to have clinical relevance, but it is not an immunologic approach. With the use of frozen sections and both polyclonal and monoclonal antibodies, a comprehensive immunohistologic study was made of 564 biopsy specimens 1) for determination of the utility of the principle of monoclonality in differentiating benign from malignant lymphoproliferative disorders, 2) for definition of the immunohistochemical phenotypes of histologically benign and malignant cellular proliferations, and 3) for evaluation of the immunologic phenotype of 257 non-Hodgkin's lymphomas classified by the International Working Formulation. Two hundred seven "reactive benign" lymphoproliferations demonstrated polyclonal immunostaining. Monoclonal kappa light chain immunostaining was demonstrated in 3 of 4 cases classified as atypical hyperplasia, two of which had coexistent NHL or subsequently developed overt NHL. Frozen tissue sections were found to be essential for demonstration of immunoglobulin and glycoprotein membrane antigens. The results of immunohistochemical studies were readily integrated with the International Formulation. Although diffuse mixed and small lymphocytic lymphomas were immunologically heterogeneous (both T- and B-cell), follicular lymphomas were invariably of B-cell type, and immunoblastic lymphomas originating from homogeneous T- and B-cell populations were identified.

Antibodies, Monoclonal↗

Membranous glomerulonephritis associated with industrial mercury exposure. Study of pathogenetic mechanisms.

The nephrotoxicity associated with mercury may be manifested as either acute tubular necrosis or an immune complex glomerulonephritis, depending upon the conditions under which the patient is exposed to the metal. Two patients with industrial exposure to mercury developed the nephrotic syndrome due to membranous glomerulonephritis. A multidisciplinary approach was used to define more precisely the pathogenetic mechanisms involved in the production of the glomerular lesion. Although glomeruli were normal by light microscopy, immunohistochemical studies demonstrated confluent finely granular epimembranous deposits of IgG and C3. This distribution was confirmed at the ultrastructural level with immunoelectron microscopy. High resolution elemental analysis of electron dense inclusions in tubular epithelial phagolysosomes demonstrated energy dispersion spectra characteristic of coexisting mercury and selenium. Eluates from the biopsy material were not immunoreactive against normal rat or human kidney. There was no immunoreactivity of epimembranous deposits with antibodies having renal tubular epithelial antigen or urinary uromucoid specificity. These observations suggest that a distinctive immunopathologic lesion is associated with mercury-associated membraneous glomerulonephritis, that the role of the metal itself may only be coincidental, and that the involved antigen remains unknown. Prednisone therapy had no documented persistent beneficial influence upon the level of proteinuria in one patient who has been lost to follow-up. In one patient not treated with steroid therapy, withdrawal of exposure to the metal resulted in disappearance of mercury from body fluids and clinical remission.

Adult↗

Light chain nephropathy.

In 13 specimens of renal tissue from 11 patients, deposits of monoclonal immunoglobulin light chains and continuous granular electron-dense material within tubular basement membranes and in association with the glomerular basement membrane were identified. All but one patient were men n the fifth to seventh decades of life, and each presented with azotemia and features of glomerular rather than tubulointerstitial disease. Osteolytic bone lesions occurred in only three patients, and a bone marrow plasmacytosis greater than 30 percent consistent with plasma cell myeloma was identified in only four patients. Light chain distribution in the nephron was confirmed with immunoelectron microscopy and was not associated with deposition of other serum proteins such as immunoglobulin heavy chains, complement, transferrin, alpha 2 macroglobulin and albumin. The electron dense deposits differed in distribution and character from those associated with membranoproliferative glomerulonephritis type II (dense deposit disease), amyloidosis, cryoglobulinemia, macroglobulinemia and benign monoclonal gammopathy. Serum from six of these patients did not bind to normal human or rat renal parenchyma in vitro. Kappa light chain nephropathy was characterized by predominant linear tubular basement membrane kappa deposits, and nodular mesangial and linear glomerular basement membrane kappa immunostaining. Lambda light chain nephropathy was characterized by linear lambda glomerular basement membrane and tubular basement membrane immunostaining. Manifestations of glomerular dysfunction dominated the clinical presentation of light chain nephropathy, and most patients did not have typical features of multiple myeloma. The diagnosis was predicated upon thorough immmunohistologic assessment of renal biopsy material.

Adult↗

Comparison of alternative chromogens for renal immunohistochemistry.

Renal immunomicroscopy using enzyme labeled reagents has been shown to be a reliable method for the identification of immunoglobulins and complement in the routine evaluation of glomerular disease. However, the potential carcinogenicity of benzidine derivatives used in the procedure represents a major disadvantage of the technique. With a series of 55 renal biopsy specimens evaluated by light microscopy, immunofluorescence, and electron microscopy from patients with a variety of renal diseases, a study was done comparing aminoethylcarbazole and the Hanker-Yates reagent (p-phenylenediamine and pyrocatechol), chromogens chemically unrelated to benzidine. Aminoethylcarbazole was not suitable for renal immunomicroscopy, since in cases of antiglomerular basement membrane disease the color reaction product was finely granular at high magnification. Specimens immunostained with the Hanker-Yates reagent yielded permanent water insoluble reaction products and immunomicroscopic patterns identical to the results observed with immunofluorescence in all cases. To our knowledge, no carcinogenic properties have been identified for p-phenylenediamine or pyrocatechol. The Hanker-Yates reagent may be used routinely for renal enzyme immunomicroscopic studies with no currently identified carcinogenic hazard to laboratory personnel.

3,3'-Diaminobenzidine↗

Immunohistochemistry of fresh-frozen lymphoid tissue with the direct immunoperoxidase technic.

Recent evidence suggests that immunofluorescence is superior to immunohistochemistry for the study of lymphomas, since the latter procedure often results in identification of polyclonal cytoplasmic immunoglobulins or negative immunostaining in non-Hodgkin's lymphomas marking monoclonal with immunofluorescence. However, immunohistochemical studies are usually applied to paraffin-embedded tissues. A modified direct immunoperoxidase procedure using fresh-frozen cryostat tissue sections, short incubation with peroxidase-labeled antikappa and antilambda antisera, and chromogens chemically unrelated to benzidine was developed. Non-Hodgkin's lymphomas previously characterized by direct immunofluorescence showed monoclonal surface membrane-associated light chains outlining each neoplastic cell. Follicular (nodular) lymphomas were characterized by monoclonal light chains in neoplastic nodules with compressed negative or polyclonal rims. Diffuse non-Hodgkin's lymphomas demonstrated diffuse individual cellular monoclonal staining. Five normal lymph nodes showed polyclonal immunostaining of follicular centers. The immunostained slides resulting from this procedure are permanent preparations amenable to counterstaining.

Frozen Sections↗

Alternate chromogens as substitutes for benzidine for myeloperoxidase cytochemistry.

Myeloperoxidase staining methods for classification of leukemias have traditionally employed benzidine dihydrochloride as the chromogen. Recent Occupational Safety and Health Administration regulations have classified benzidine as a carcinogen, which severely restricts its use in the clinical laboratory. Twenty-two specimens from normal control subjects and leukemia patients, previously classified by FAB criteria, were stained with benzidine and two alternate chromogens, diaminobenzidine and Hanker-Yates reagent (p-phenylenediamine and pyrocatechol). In a random, blind fashion, three experienced observers scored the stains from each case according to quality of smear, degree of peroxidase positivity, tinctorial distinction between nucleus and cytoplasm, and overall acceptability of the stain. All three observers rated the substitute chromogens as adequate for routine myeloperoxidase cytochemical staining. It is concluded that either of the methods studied would have clinical utility and can substitute for benzidine as a myeloperoxidase chromogen.

Benzidines↗

Tissue immunomicroscopic evaluation of monoclonality of B-cell lymphomas: comparison with cell suspension studies.

A series of 80 tissues removed from patients having a variety of lymphoproliferative disorders were comparatively studied by cell suspension and cryostat frozen section tissue immunomicroscopic technics. Of 39 cases of non-Hodgkin's lymphomas studied by cell suspension, only 18 had surface immunoglobulins (SIg) markers consistent with monotypia (46%). Conversely, immunohistochemistry showed 18 cases (92%). Among the 18 cases in which there was no correlation between immunohistochemistry and cell suspension studies (46%), a variety of cytologic variants of non-Hodgkin's lymphomas was recognized, including nodular poorly differentiated lymphocytic lymphoma, nodular large cell lymphoma, and a soft tissue plasmacytoma. The lack of correlation between the two technics may be due to several different mechanisms, including the selective enrichment of the suspension by nonneoplastic cell populations resulting in a sampling artifact, the disappearance of endogenous SIg in large or plasmacytoid lymphocytes, and the presence of membrane-bound exogenous polyclonal SIG. Immunohistochemistry represents a reliable, simple technic for establishing monotypia in non-Hodgkin's B-cell lymphomas.

Antibodies, Neoplasm↗