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Biomedical subjects

R I Fox

Publications and source records attributed to R I Fox.

At least 91 records · Page 5Linked to original sources
PubMed1986

Lack of reactivity of rheumatoid arthritis synovial membrane DNA with cloned Epstein Barr virus DNA probes.

Rheumatoid arthritis (RA) synovial membranes contain a 62,000 dalton (62 Kd) molecule that shares an antigenic epitope with the EBNA-1 antigen of Epstein Barr virus (EBV). This cross-reactive epitope(s) is defined by a monoclonal anti-EBNA-1 antibody (MoAb P135) and by a rabbit antibody directed against a (glycine-alanine)-containing synthetic peptide from the internal repeat region-3 (IR-3) of EBNA-1. To determine whether this 62 Kd protein may result from EBV infection of RA synovial membranes, we used cloned DNA probes from the Bam M, Bam V, and Eco D regions of EBV. These probes did not show detectable reactivity with RA synovial membrane DNA in Southern blotting or slot blotting experiments. Reconstruction experiments performed with purified EBV DNA demonstrated the ability to detect 0.03 pg of viral DNA per 20 micrograms of normal genomic DNA, or approximately 1 EBV copy per 100 cells. In contrast, we found a low but significant level of reactivity of RA synovial membrane DNA with the EBV-encoded Bam K probe that encodes the EBNA-1 antigen. However, this probe also was reactive with normal genomic DNA to a similar extent. These results suggest that the 62 Kd antigen in RA synovial lining cells is probably encoded by cellular genes similar to the IR-3 region of EBV and does not result from EBV infection of the RA synovial membrane.

Aged↗
PubMed1986

Expression of three cross-reactive idiotypes on rheumatoid factor autoantibodies from patients with autoimmune diseases and seropositive adults.

Approximately one-half of human monoclonal IgM anti-IgG autoantibodies (rheumatoid factors (RF] from unrelated individuals with cryoglobulinemia coordinately express three cross-reactive idiotypic antigens (CRI). The CRI are detected with: 1) monoclonal antibody 17.109, which recognizes a conformation-dependent CRI on K-light chains; and 2) two rabbit anti-peptide antibodies that react with primary sequence-dependent CRI (PSL2 and PSL3) corresponding to the conserved second and third K-chain complementarity-determining regions, respectively. In the present experiments, the structural features of polyclonal RF autoantibodies from diverse patients with rheumatoid arthritis and from those with primary Sjögren's syndrome, and from seropositive elderly subjects without overt autoimmune diseases, were investigated with these three defined anti-CRI reagents. The pattern of expression of the CRI differed among patient groups. Only the RF autoantibodies from Sjögren's syndrome patients frequently displayed all three CRI. However, the RF from nearly every subject tested, including patients with rheumatoid arthritis, were enriched in the primary sequence-dependent PSL2-CRI as compared to RF-depleted Ig from the same subjects. Amino acid sequence analysis of monoclonal IgM-RF indicates that PSL2-CRI-positive light chains probably represent the products of a single Vk gene. Therefore, a proportion of the polyclonal RF from different autoimmune states may represent somatic variants of this germ-line RF Vk gene which retain the PSL2 sequence as a common element.

Adult↗
PubMed1986

Interferon-gamma-dependent modulation of C3b receptors (CR1) on human peripheral blood monocytes.

Cell surface expression of the C3b receptor (CR1) was transiently down regulated on purified human monocytes exposed to purified recombinant human interferon-gamma(rIFN-gamma). Receptors were quantitated by using CR1-specific monoclonal antibody by radioimmunoassay or flow cytometry and by rosette analysis with the use of C3b-coated bovine erythrocytes. The reduction of CR1 was dependent on the dose of IFN-gamma used and the time of cellular exposure. Down-regulation was transient, with maximum loss occurring after 2 to 3 days of stimulation with IFN-gamma. However, after 6 days CR1 was re-expressed at the plasma membrane. This effect was observed with monocytes isolated by either centrifugal elutriation or adherence on fibronectin-coated dishes. IFN-gamma-dependent diminution of CR1 occurred concomitant with increased expression of Fc receptors and HLA-DQ antigen and unaltered expression of the C3bi receptor (CR3). The mechanism of CR1 loss from the monocyte cell surface was not due to internalization, because total cellular levels of CR1 (plasma membrane and intracellular pool) also decreased in response to IFN-gamma. These results indicate that IFN-gamma may be involved in regulating CR1 on mononuclear phagocyte surfaces.

Cell Line↗
PubMed1986

Sjögren's syndrome. Proposed criteria for classification.

The term "Sjögren's syndrome" (SS) is frequently used to describe the occurrence of keratoconjunctivis sicca and xerostomia in association with an autoimmune disorder. However, well-defined criteria for the classification of SS have not been established, and this diagnosis is being applied to a wide spectrum of conditions, ranging from clear "autoimmune" disease in some patients, to sicca complaints without evidence of a systemic immune process in elderly patients. Here, we review the clinical and laboratory features of patients referred for evaluation of sicca symptoms. In particular, we emphasize the need for care in choosing the site for minor salivary gland biopsy, and we describe the histologic features that aid in the evaluation of these biopsy specimens. In an attempt to identify a population of patients whose conditions might have a common etiopathogenesis and, thus, a common treatment program, we propose the following criteria for a diagnosis of SS: 1) objective evidence of keratoconjunctivis sicca, as documented by rose bengal or fluorescein dye staining; 2) objective evidence of diminished salivary gland flow; 3) minor salivary gland biopsy, obtained through normal mucosa, with the specimen containing at least 4 evaluable salivary gland lobules, and having an average of at least 2 foci/4 mm2; 4) evidence of a systemic autoimmune process, as manifested by the presence of autoantibodies, such as rheumatoid factor and/or antinuclear antibody. The diagnosis of "definite SS" would be made when all 4 criteria are met; the diagnosis of "possible SS" would be made when 3 criteria are present. Specific exclusions for this diagnosis are preexisting lymphoma, graft-versus-host disease, sarcoidosis, and acquired immunodeficiency disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗
PubMed1986

Expression of histocompatibility antigen HLA-DR by salivary gland epithelial cells in Sjögren's syndrome.

Recent studies have suggested that the induction of HLA-DR antigens on epithelial cells plays an important role in the pathogenesis of autoimmune endocrine-exocrine disorders. We found that salivary gland epithelial cells (i.e., acinar and ductal cells) in salivary gland biopsy specimens from patients with primary Sjögren's syndrome (keratoconjunctivitis sicca) expressed high levels of HLA-DR antigen, which were detected by staining frozen tissue sections with monoclonal antibodies and immunoperoxidase technique. In contrast, salivary gland epithelial cells from normal subjects did not express this antigen. Lymphocytes eluted from the salivary gland biopsy specimens of patients who had Sjögren's syndrome produced a soluble factor that stimulated HLA-DR synthesis by a salivary gland-derived cell line (Sal-1). These tissue culture supernatants contained gamma-interferon, and their ability to induce HLA-DR synthesis was blocked by monoclonal anti-gamma-interferon antibody. These results demonstrate the presence of HLA-DR antigen on salivary gland epithelial cells and suggest that local production of gamma-interferon plays a role in this induction.

Cells, Cultured↗
PubMed1986

Expression of a cross-reactive idiotype on rheumatoid factor in patients with Sjogren's syndrome.

Primary Sjogren's syndrome (SS) is a systemic autoimmune disorder characterized by lymphocytic infiltration of salivary and lacrimal glands. These patients have evidence of marked B cell hyperactivity, including the production of autoantibodies such as rheumatoid factor (RF) and an increased frequency of non-Hodgkin's lymphoma. We now demonstrate that RF from 12/15 SS patients contains a cross-reactive idiotype (CRI) on their kappa light chain defined by a monoclonal antibody (MoAb 17-109) and immunoblotting. This CRI was associated with immunoglobulin (Ig) A-RF, and to a lesser extent with IgM-RF molecules on the basis of direct binding studies. With the use of immunoperoxidase techniques to stain frozen tissue sections, B cells containing cytoplasmic Ig reactive with MoAb 17-109 were detected in the salivary gland biopsies from 11/12 SS patients at high frequencies, and in the blood from the same patients at much lower frequencies. One patient with pre-existant SS developed non-Hodgkin's lymphoma with tumor cells and RF paraprotein reactive with MoAb 17-109. Evaluation of serial biopsies over a 4-yr period showed a progressive increase in the proportion of B cells bearing the CRI. In contrast, synovial membrane biopsies from RA patients lacking sicca symptoms did not contain B cells expressing the CRI. Because previous studies have demonstrated that MoAb 17-109 detects a CRI on RF paraproteins from patients with lymphoma, B cells bearing this CRI may have increased frequency of neoplastic transformation. SS patients provide an opportunity to study the expression of this CRI and to understand the transition of B cell clones from autoimmune proliferation to neoplastic transformation.

Adolescent↗
PubMed1986

Characterization of a crossreactive idiotype in Sjögren's syndrome.

Sjögren's syndrome (SS) is characterized by lymphoid infiltration of the salivary glands and autoantibody production. Rheumatoid factor (RF) in patients with primary SS (1 degree SS) contains a crossreactive idiotype (CRI) defined by a monoclonal antibody (MoAb 17-109). This CRI was located on the kappa light chain by immunoblotting methods. A high frequency of CRI+ B cells was found in SS salivary gland biopsies, suggesting this tissue as the site of production for this autoantibody. Further characterization of CRI+ RF from SS patients was performed using antibodies prepared against synthetic peptides corresponding to the hypervariable region of RF paraproteins from patients with Waldenström's macroglobulinemia (WM). These results demonstrate a close structural relationship between RF in SS and WM patients. To analyze the genes that encode these RF in SS patients, B cell hybridomas that secreted CRI+ immunoglobulin were created and their DNA analyzed by Southern blot techniques. These hybridomas will allow us to determine the DNA sequence of kappa genes encoding the CRI and to identify adjacent regulatory genes that may promote high levels of CRI expression.

Cross Reactions↗
PubMed1985

Ocular and oral problems in arthritis. How to recognize, when to refer.

Recognition of oral and ocular problems is important in the management of arthritis. Although the focus of attention is usually on joint problems, patients with these chronic disorders require a comprehensive approach to their total medical care. Physicians need to watch for physical signs of significant inflammation and should alert their patients to watch for significant symptoms.

Anti-Inflammatory Agents↗
PubMed1985

Staining and fluorescence-activated cell sorter analysis of human lymphocytes using antibodies to a short, chemically synthesized human IL-2 peptide.

A rabbit antibody against a chemically synthesized peptide (p84), encompassing residues 59-72 of mature human interleukin 2 (IL-2), has been shown to react specifically with natural or recombinant IL-2. This antibody was used in immunoperoxidase and immunofluorescence techniques for identification of IL-2-containing cells in human peripheral blood or tonsils. Lymphocytes were stimulated with T-cell mitogens (PHA, PWM), fixed, and incubated with affinity-purified anti-p84 antibody, followed by appropriately conjugated secondary antibodies. FACS analysis demonstrated a low fluorescence intensity in 5 to 15% of unstimulated cells. In contrast, 40-60% of mitogen-stimulated cells were stained at a high fluorescence intensity. Staining was inhibited by preincubating the anti-p84 antibody with the homologous peptide or recombinant IL-2, but not by unrelated peptides. In immunoperoxidase staining, anti-p84 antibody reacted selectively with an enriched T-cell population which was 95% Leu 5+, 80% Leu 3+, and 60% Tac+. Thus, this antibody to a synthetic IL-2 peptide reacts selectively with activated T cells, and may serve, therefore, as a useful tool for visualization and enumeration of IL-2-containing cells in blood and tissues.

Animals↗
PubMed1985

Sjogren's syndrome: a persistent clinical problem.

One hundred sixty patients with Sjogren's syndrome have been evaluated and managed at Scripps Clinic. Objective diagnosis has relied heavily on rose-bengal vital staining and corneal slit lamp examination to establish the presence of KCS and lip biopsy. The role of the head and neck surgeon in evaluating the patient with "dry mouth" is discussed. Usually Sjogren's syndrome is managed nonsurgically, but problems of abscess, recurrent infection, disfigurement, and malignant transformation may result in the need for total parotidectomy with nerve preservation. Radiation for Sjogren's syndrome is rarely, if ever, indicated. The etiology of Sjogren's syndrome may be closely tied to the homogeneous genetic background of its patients and the presence of a chronic immunogenic stimulus well recognized in the secondary form but less clear in the primary.

Diagnosis, Differential↗
PubMed1985

Characterization of a membrane surface glycoprotein associated with T-cell activation.

A cell surface antigen (gp140) was previously shown to exist on T cell subsets as well as on monocytes and macrophages in normal peripheral blood. Elevated expression of this antigen was associated with immune system disorders, acute lymphocytic leukemias, and in vitro activation of T cells. The antigen could be identified with monoclonal antibody (MAb) T305. Gp140 was a biosynthetic product of T cells because it could be labeled with [3H]leucine or [3H] glucosamine. Biochemical studies of gp140 used high performance liquid chromatography with nitrocellulose blotting to isolate aliquots suitable for 125I radiolabeling and immunoprecipitation to demonstrate: a) a reduction in m.w. of gp140 KD to 90 KD after deglycosylation by trifluoromethanesulfonic acid, b) alteration of isoelectric point from 4.1 to 5.7 after neuraminidase treatments, c) absence of N-linked sugars based on resistance to endoglycosidase F, d) resistance to trypsin and chymotrypsin digestion but susceptibility to pronase, and e) presence of sialic acid and lactosaminoglycan as O-linked sugars. Gp140 could be labeled with the periodate/NaB[3H]4 technique, indicating its similarity to a class of sialoglycoproteins previously described on activated T-cells in mouse and man. The antigenic epitope recognized by MAb T305 contains sialic acid linked (2----3) to galactose; however, periodate oxidation of the exocyclic ring of sialic acid did not affect binding by MAb T305. In an attempt to determine the functional role of gp140, we tested the ability of MAb T305 to block: a) proliferation of peripheral blood lymphocytes to mitogens, b) response to interleukin 2 (IL 2) of an IL 2 dependent T cell line, and c) growth of a T-ALL derived cell line. No inhibition of proliferation or growth was noted. Although the function of gp140 remains unknown, its association with lymphocyte activation and certain disease states suggests that it may provide a target for modulation of the immune response. These studies characterize the structural features of gp140 and further define the epitope recognized by MAb T305.

Animals↗
PubMed1985

Production of interleukin 2 (IL 2) by salivary gland lymphocytes in Sjögren's syndrome. Detection of reactive cells by using antibody directed to synthetic peptides of IL 2.

Because abnormalities in interleukin 2 (IL 2) production have been reported in the blood of patients with certain autoimmune diseases, we have examined the lymphocytes from patients with Sjögren's syndrome (SS) in which it is possible to obtain simultaneous samples of inflammatory site (i.e., salivary gland) lymphocytes and blood lymphocytes. We found that IL 2 production by peripheral blood lymphocytes (PBL) after mitogen stimulation was markedly diminished (4 +/- 2 U/ml) in 8/32 SS patients. However, salivary gland lymphocytes (SGL) from six out of six SS patients (including three patients with low IL 2 production by their PBL) had a high level of IL 2 production (97 +/- 32 U/ml), suggesting that IL 2 production by inflammatory site lymphocytes may differ from blood lymphocytes in the same patients. Low IL 2 production by a patient's PBL was not correlated with the patient's age, duration of disease, immunoglobulin level, or presence of antinuclear antibodies. Low IL 2 production was associated with a decreased ratio of Leu-3a/Leu-2a positive cells (p less than 0.05) and with an increased proportion of "activated" T cells expressing HLA-DR and gp140 (p less than 0.05). To determine the proportion of PBL and SGL containing cytoplasmic IL 2-like material, we used affinity-purified rabbit antibodies prepared against chemically synthesized peptides of human IL 2. Before mitogen stimulation, PBL were not stained by these antibodies (less than 1% reactive cells), whereas SGL T cells eluted from the salivary gland of SS patients contained a small (3.4% +/- 1.8) proportion of reactive cells. A similar proportion (2.4% +/- 1.2) of reactive cells was noted when frozen tissue sections of salivary gland biopsies were examined with these antibodies. After mitogen stimulation, 35% +/- 17 of PBL and 56% +/- 18 of SS SGL were specifically stained with anti-IL 2 peptide antibodies. In summary, these studies demonstrate a significant difference in IL 2 production between PBL and SGL of the same patients. Furthermore, antibodies against IL 2 peptides provide a powerful tool for detection of T cells producing IL 2 in vitro and in situ, and for understanding the role of this lymphokine in pathogenesis.

Adult↗
PubMed1985

Salivary gland lymphocytes in primary Sjogren's syndrome lack lymphocyte subsets defined by Leu-7 and Leu-11 antigens.

Primary Sjogren's Syndrome (SS) is an autoimmune disease characterized by dry eyes and dry mouth due to lymphocytic infiltration of lacrimal and salivary glands. Biopsies of their salivary glands provided an opportunity to characterize the phenotypic and functional properties of inflammatory site lymphocytes. We found that the salivary gland lymphocytes (SGL) of SS patients differed from the peripheral blood lymphocytes of the same patients because: a) SGL lacked lymphocytes reactive with anti-Leu-7 and anti-Leu-11 monoclonal antibodies; b) SGL lacked natural killer (NK) activity; and c) SGL lacked the ability to suppress polyclonal B cell responses in the presence of complement fragment C3a, a function that requires the presence of Leu-7+ cells. These studies also showed that the SGL of SS patients differed from tonsillar lymph node (LN) lymphocytes of immunologically normal individuals because tonsillar LN contained Leu-7+ T cells, and tonsillar LN could suppress polyclonal B cell responses in the presence of the complement fragment C3a. The absence of this regulatory subset in the salivary glands of SS patients may contribute to pathogenesis, because these cells may be important in the suppression of polyclonal antibody synthesis and in the elimination of neoplastic or viral infected cells.

Adolescent↗
PubMed1985

Structural similarities in the kappa light chains of human rheumatoid factor paraproteins and serum immunoglobulins bearing a cross-reactive idiotype.

The monoclonal antibody (MoAb) 17.109 recognizes a cross-reactive idiotype (CRI) associated with the light chains of Waldenstrom's macroglobulins with rheumatoid factor (RF) activity. The MoAb also reacts with a proportion of IgM-RF molecules from the sera of rheumatoid arthritis and primary Sjogren's syndrome patients, and from the sera of seropositive normal human subjects. In the present experiments, we used affinity chromatography to purify the 17.109 CRI-positive immunoglobulin from serum and have analyzed the isolated material by Western blotting. The purified 17.109 CRI-positive material from the sera of rheumatoid arthritis patients, Sjogren's syndrome patients, and normal subjects contained exclusively kappa light chains, and had demonstrated RF activity. In every case the 17.109 CRI-positive isolates reacted with antibodies against synthetic peptides corresponding to both the conserved second and third complementarity-determining regions (CDR) of the monoclonal kappa IgM-RF paraprotein Sie. The binding was inhibited specifically by the free peptides in solution. The antipeptide antibodies did not react appreciably with unfractionated human immunoglobulin. The data establish that the 17.109 CRI-positive immunoglobulin from diverse human sera have similar or identical second and third light chain CDR. These results suggest i) that the MoAb 17.109 identifies the protein product of a single or a very few V kappa genes, ii) that the ability to make kappa light chains with the 17.109-associated variable region is widespread in the human population, and iii) that the 17.109-defined kappa variable region segment is associated with IgM-RF autoantibodies.

Amino Acid Sequence↗
PubMed1984

Immunohistologic characterization of synovial membrane lymphocytes in rheumatoid arthritis.

Synovial membrane biopsy specimens from 15 rheumatoid arthritis patients were examined using routine histologic stains and monoclonal antibodies directed against cell surface antigens. Three patterns of lymphoid cell infiltrates were recognized: 1) diffuse infiltration of T cells that surrounded clusters of germinal center B cells (3 patients); 2) diffuse T cell infiltration, lacking germinal centers (8 patients); and 3) proliferation of subsynovial fibroblasts, with relatively few lymphoid cells (4 patients). The synovial, subsynovial, and perivascular tissues in each of the patterns exhibited a high frequency of HLA-DR antigen, HLA-DS antigen, transferrin receptor, and/or epidermal growth factor receptor. In contrast, normal or osteoarthritic synovial tissues did not display a marked increase of these antigens or receptors. Cells bearing natural killer antigen were infrequent in each of these patterns. Active synovitis, synovial effusions, anemia, and elevated sedimentation rate were present in rheumatoid arthritis patients with each of the three histologic patterns. Immunohistologic characterization of synovial membrane infiltrates by these monoclonal antibodies provides additional information about pathogenesis of rheumatoid arthritis and may help in predicting responses to different therapeutic modalities.

Arthritis, Rheumatoid↗