Analyses of lymphocytes from patients with rheumatoid arthritis and systemic lupus erythematosus. Occurrence of interfering cold-reactive antilymphocyte antibodies

Antilymphocyte autoantibodies generate T cell-C4d signatures in systemic lupus erythematosus

T cells bearing C4d, a complement activation product (CAP), have been shown to be highly sensitive and specific as diagnostic biomarkers for systemic lupus erythematosus (SLE). T cells bearing C4d are also functionally abnormal, suggesting a role for cell-bound CAPs in lupus pathogenesis. However, the mechanism responsible for generation of T-C4d has not been determined. The purpose of this cross-sectional and prospective study was to investigate the potential role of anti-T-cell autoantibodies in the generation of the T cell-bound C4d (T-C4d) signatures in SLE. Briefly, T cells from patients with SLE (n = 326), patients with other inflammatory diseases (n = 185), and healthy controls (n = 48) were characterized for surface deposition of either or both of C4d and immunoglobulin (Ig) by flow cytometry. In vitro phenotype transfer experiments were performed to characterize Ig from patients with SLE for the capacity to generate T-C4d signatures in vitro. The results demonstrate that individual patients with SLE harbor specific signatures reflecting the presence of either or both of C4d and Ig on their T cells and T-cell subsets. In addition, SLE patient-specific signatures can be transferred in vitro to normal T cells by exposure to Ig purified from the signature donor. Complement activation does not proceed through the generation of C5b-9 (membrane attack complex) or cellular lysis, and T-C4d does not correlate with lymphopenia. In conclusion, these results suggest that patient-specific T-C4d signatures are generated by anti-T-cell autoantibodies that trigger sublytic complement activation, a previously unrecognized pathway in lupus pathogenesis.

Physical and biophysical assessment of highly fluorescent, magnetic quantum dots of a wurtzite-phase manganese selenide system

Combining fluorescence and magnetic features in a non-iron based, select type of quantum dots (QDs) can have immense value in cellular imaging, tagging and other nano-bio interface applications, including targeted drug delivery. Herein, we report on the colloidal synthesis and physical and biophysical assessment of wurtzite-type manganese selenide (MnSe) QDs in cell culture media. Aiming to provide a suitable colloidal system of biological relevance, different concentrations of reactants and ligands (e.g., thioglycolic acid, TGA) have been considered. The average size of the QDs is ∼7 nm, which exhibited a quantum yield of ∼75% as compared to rhodamine 6 G dye(®). As revealed from time-resolved photoluminescence (TR-PL) response, the near band edge emission followed a bi-exponential decay feature with characteristic times of ∼0.64 ns and 3.04 ns. At room temperature, the QDs were found to exhibit paramagnetic features with coercivity and remanence impelled by TGA concentrations. With BSA as a dispersing agent, the QDs showed an improved optical stability in Dulbecco's Modified Eagle Media(®) (DMEM) and Minimum Essential Media(®) (MEM), as compared to the Roswell Park Memorial Institute(®) (RPMI-1640) media. Finally, the cell viability of lymphocytes was found to be strongly influenced by the concentration of MnSe QDs, and had a safe limit upto 0.5 μM. With BSA inclusion in cell media, the cellular uptake of MnSe QDs was observed to be more prominent, as revealed from fluorescence imaging. The fabrication of water soluble, nontoxic MnSe QDs would open up an alternative strategy in nanobiotechnology, while preserving their luminescent and magnetic properties intact.

Certain polyclonal antinuclear antibodies cross-react with the surface membrane of human lymphocytes and granulocytes

Five out of 24 human sera with antinuclear antibody (ANA) titers of 1250 or more contained ANA that bound in vitro to normal viable human mononuclear blood cells and granulocytes, but not to erythrocytes. The antibodies can be eluted off from the cell membranes and shown to possess ANA activity. Antinative DNA antibodies and lupus erythematosus factor were not recovered in eluates, indicating that they did not react with the cells. The cells absorbed 75%-87% of the ANA activity from three sera. ANA reacted with both T-lymphocyte-depleted and -enriched mononuclear cells. No or minimal amounts of ANA bound to mouse spleen cells in suspension; in contrast, the ANA eluted from human cells reacted with nuclei of smeared mouse spleen cells. The cross-reacting antibodies were predominantly IgG that bound well at 37 degrees C, and F(ab')2 fragments carried both activities. The ANA-binding plasma membrane antigen was resistant to trypsin and RNAse but was completely inactivated by glutaraldehyde. The data indicate that human leukocyte plasma membranes and cell nuclei from many species contain a cross-specific antigen. Alternatively, the antigen may be produced in the nucleus and somehow attach to the plasma membrane.

Henry Kunkel Festschrift

This Festschift by his former trainees is dedicated to the memory of Dr Henry G Kunkel. Dr Kunkel spent most of his academic life at The Rockefeller University. He has been called the father of Clinical Immunology. His trainees became professors and leaders in this field. Dr Kunkel's laboratory led to the elucidation of the immunology of the LE cell, the significance of anti-DNA and immune deposits in lupus nephritis, the recognition of antibodies to other nucleic acids and cellular constituents, the role of complement, genetics, hormones and cellular immunology--in the area of lupus and other rheumatic diseases.

Filtration leukocytapheresis therapy in rheumatoid arthritis: a randomized, double-blind, placebo-controlled trial

OBJECTIVE

To determine the efficacy and safety of filtration leukocytapheresis (LCP) for the treatment of rheumatoid arthritis (RA).

METHODS

Twenty-five patients with drug-resistant RA were randomly assigned to undergo filtration LCP and 7 to undergo sham apheresis (control group) in a randomized, double-blind, placebo-controlled study. Three apheresis procedures were performed, with 1-week intervals between procedures. The efficacy of filtration LCP was evaluated according to the American College of Rheumatology definition of improvement in RA. Medications for each patient were unchanged for at least 6 months prior to enrollment and throughout the study.

RESULTS

Tender joint counts, swollen joint counts, patient assessment of pain and global severity, physician assessment of global severity, and Health Assessment Questionnaire Disability Index were significantly improved in the LCP group compared with the control group (P < 0.05 for patient assessment of pain; P < 0.01 for all others). Seventy-nine percent of the patients in the LCP group exhibited significant overall improvement, while none of the patients in the control group were improved (P < 0.001).

CONCLUSION

The results indicate that filtration LCP is an effective and well-tolerated treatment for patients with drug-resistant RA.

Stimulation of human monocytes by anti-CD3 monoclonal antibody: induction of inflammatory mediator release via immobilization of Fc receptor by adsorbed immunoglobulin and T-lymphocytes

Human monocytes released superoxide anion, prostaglandin E2, leukotriene B4, IL-1, and TNF when exposed to plastic surfaces coated with murine anti-CD3 monoclonal antibody, OKT 3. Stimulation of mediator release by OKT 3 was dependent on the amount of antibody immobilized onto wells of plastic tissue culture plates. Soluble antibody or antibody adsorbed to monocytes and reacted with an aggregating ("cross-linking") second antibody failed to induce mediator release. Monocytes "armed" with OKT 3 formed rosettes with T cells in a fashion indistinguishable from that seen between monocytes and T cells sensitized with OKT 3. Monocytes with adsorbed OKT 3 antibodies released IL-1 beta and TNF-alpha when exposed to unsensitized T cells, although increased superoxide release could not be detected. OKT 4a, a murine IgG2a antibody that reacts with a different T cell epitope (CD4), failed to induce cytokine release from monocytes when cross-linked by T cells or a CD4+ T cell line, even in the presence of IL-2 or IFN-gamma. These data indicate that certain antibodies bound to Fc receptors (FcR) of monocytes may trigger monocyte function when reacting with cells bearing the appropriate target antigens. FcR-mediated signaling resulting in mediator release may be involved in initiating or regulating the immune response. Furthermore, systemically administered monoclonal antibodies may induce inflammatory responses and their attendant symptomatologies via their interaction with FcR-bearing inflammatory cells.

T cell receptor expression and activation of synovial lymphocyte subsets in patients with rheumatoid arthritis. Phenotyping of multiple synovial sites

Two-color flow cytometry analysis of peripheral blood and synovial lymphocytes from rheumatoid arthritis patients was performed using monoclonal antibodies directed against T cell subsets, T cell activation markers, and T cell receptors. The results showed an abnormally high percentage (greater than 15%) of CD3+, CD4-, and CD8- T cells expressing a specific receptor containing a gamma chain. Phenotypic analysis of lymphocytes infiltrating both knee joints of individual rheumatoid arthritis patients revealed very similar subset distribution and activation levels, despite strong differences in the clinical status between the 2 sites.

Lymphocytotoxic antibodies in systemic lupus erythematosus: studies of their temperature dependence, binding characteristics, and specificity in vitro

The lymphocytotoxicity of 33 lupus sera was tested against purified helper/inducer (OKT4) and cytotoxic/suppressor (OKT8) subsets of T lymphocytes at 15 degrees C and 37 degrees C in vitro. There was significantly less killing of both OKT4 and OKT8 cells at 37 degrees C (p less than 0.001 and p less than 0.01) and the ratio of OKT4/OKT8 cell killing at 15 degrees C (1.39 (0.73); mean (SD] was different from that observed at 37 degrees C (0.79 (0.42)) (p less than 0.001). OKT4 killing was greater than OKT8 killing in 21 out of 33 sera at 15 degrees C, while 22 of these sera showed predominantly OKT8 cytotoxicity at 37 degrees C. The relation between the OKT4/OKT8 cell ratio and OKT4/OKT8 serum killing was examined in 22 patients at both temperatures: a significant inverse correlation was observed at 37 degrees C (r = -0.53; p = 0.015) but not at 15 degrees C (p greater than 0.05). The addition of metabolic and cytoskeletal inhibitors increased cytotoxicity at 37 degrees C, but not IgM surface binding. A Scatchard binding analysis of the reaction at 15 degrees C showed that large numbers of antibody molecules were bound to both subsets, with a low average dissociation constant of less than or equal to 6 x 10(-8) mol/l, and electrophoretic blotting indicated that the target surface antigens varied in type and number among individual lymphocytotoxic sera. The demonstration of temperature dependent, tight binding between lymphocytotoxic antibody and variable antigens on the T cell surface emphasises the potential for this phenomenon to affect lymphocyte function in vivo in patients with systemic lupus erythematosus.

Serum inhibitors of interleukin-2

Interleukin-2 (IL-2) is an important modulator of cell-mediated immunity. Its activity is suppressed by various serum inhibitors generated under normal and pathological conditions. It is believed that an inhibitor which occurs in normal serum is a T-cell derived heat labile protein (or protein-glycolipid complex), and it acts in a homeostatic mechanism to restrict IL-2 action to the vicinity of the activated T cells. Changes in inhibitory activity have been found in various physiological and pathological states, e.g. during ontogeny, in systemic lupus erythematosus, in rheumatoid arthritis, and with some systemic infections. There are also suggestions that some tumor cells generate IL-2 inhibitors which diminish killer cell activity against the tumor. It is possible that a better understanding of IL-2 inhibitors would help elucidate some pathological mechanisms connected with disturbed cellular immune responses.

Functional and phenotypical characterization of activated T cells from intra-articular sites in inflammatory joint diseases. Possible modulation of the CD3 antigen

The presence of activated T lymphocytes bearing interleukin 2 (IL-2) receptors and HLA class II (Ia) antigens accompanied by impaired T cell functions such as a decreased mitogenic responsiveness are characteristic findings, especially in intra-articular sites in chronic inflammatory joint diseases. The objective of the present study was to further characterize these in vivo activated T cells by the investigation of IL-2 production and a possible T cell receptor modulation. IL-2 receptors were found to be expressed primarily in the CD4+ subset. The Ia+ subset expressing both DR and DQ antigens showed a weaker mitogen-induced response as compared to the Ia- fraction. A decreased mitogen-induced IL-2 production and a lower response to anti-CD3 monoclonal antibodies was observed with synovial T lymphocytes as compared to peripheral blood T cells. The density of the CD3 molecule, known to be closely associated with the T cell receptor, was significantly lower in intra-articular sites, while other T cell-specific surface molecules were expressed to a similar extent in both compartments. The decreased synovial T cell mitogenesis was not restored by the addition of lymphokines (IL-1 and IL-2) or blood monocytes, nor by removing CD8+ T cells. These data present further evidence for a significant T cell activation in intra-articular sites in chronic inflammatory joint diseases. The decreased expression of the CD3 glycoprotein suggests a modulation by so far unidentified antigen(s), which could also be responsible for the weak T cell response elicited by polyclonal mitogens.

Changes in anti-lymphocyte and anti-Ia antibodies during pregnancy in systemic lupus erythematosus

Anti-lymphocyte antibodies reactive with monocyte-depleted lymphocytes, T cells, or B cells were studied in 43 nonpregnant and 23 pregnant systemic lupus erythematosus (SLE) patients. Anti-Ia specificity was assayed in an enzyme-linked immunosorbent assay system. No difference in mean lymphocytotoxicity was noted between pregnant and nonpregnant SLE patients; however, anti-Ia lymphocyte antibody associated with disease activity was lower (P less than 0.01) in pregnant than in nonpregnant SLE patients. Lymphocytotoxic or anti-Ia antibody activity did not reliably predict the outcome of individual pregnancies.

Immunoglobulin from systemic lupus erythematosus serum induces interferon release by normal mononuclear cells

Ig fractions from patients with systemic lupus erythematosus (SLE) were tested with cultured normal peripheral blood mononuclear cells for induction of interferon release. Lymphocyte eluates, euglobulins containing IgG and IgM, and IgG or IgM from DEAE or sucrose gradients all induced interferon production. Lymphocytotoxic antibody in SLE sera showed a high correlation with capacity of isolated Ig fractions to induce interferon. Most interferon produced was of the gamma type. Monoclonal SLE IgM antilymphocyte antibody induced interferon synthesis.

In vitro stimulation of lymphocytes from patients with rheumatoid arthritis

Peripheral blood lymphocytes from patients with rheumatoid arthritis (RA) and from normal controls were compared in 20 microliters droplet cultures following stimulation with phytohemagglutinin or concanavalin A. The dynamics of proliferation were significantly changed in RA. Higher numbers of cells in culture were needed to achieve the same response. This may explain the low proliferative responses of lymphocytes from some patients with RA, and apparent changes of in vitro suppressor effects, reported by other authors. Diurnal variations of lymphocytes in RA patients were also studied. No differences in the response to mitogen of lymphocytes taken at 7 AM and 7 PM were found.

Spontaneous production of antibodies to deoxyribonucleic acids in patients with systemic lupus erythematosus

In vitro spontaneous anti-DNA antibody production in patients with systemic lupus erythematosus (SLE) was examined. SLE lymphocytes produced IgG and IgM anti-DNA antibody from the third culture day, and reached a plateau on the seventh culture day. This anti-DNA antibody activity in 7-day culture supernatant was abolished by pretreatment of the lymphocytes with cycloheximide, suggesting de novo immunoglobulin synthesis was required for this spontaneous anti-DNA antibody production. Lymphocytes from patients with rheumatoid arthritis (RA) and other collagen diseases including progressive systemic sclerosis, polymyositis/dermatomyositis, and polyarteritis nodosa did not produce IgG and IgM anti-DNA antibody spontaneously, but SLE lymphocytes produced substantial amounts of IgG and IgM anti-DNA antibody spontaneously. Furthermore, active SLE produced a larger amount of IgG anti-DNA antibody than inactive SLE. We observed a significant negative correlation between the number of Ia+ T cells and IgG, but not IgM, anti-DNA antibody production. Furthermore, spontaneous IgG anti-DNA antibody production was elevated after pretreatment of SLE T cells with anti-Ia and complement, suggesting that Ia+ T cells in SLE bring about suppression of autologous B cells producing IgG anti-DNA antibody.

Biological activity of lymphocytotoxic antibodies in Graves' disease and Hashimoto's thyroiditis

Sera of 48 patients with Graves' disease (GD) and 23 with Hashimoto's thyroiditis (HT) were tested for lymphocytotoxic (LCT), granulocytotoxic (GCT) and monocytotoxic (MCT) activity. In GD, 12 patients (25%) had cold-reacting LCT and 13 patients (27%) had warm-reacting LCT. LCT were cytotoxic to both B and T cells but the majority of sera with cold-reacting LCT and eluates from lymphocytes were more cytotoxic to B lymphocytes. Warm-reacting LCT were directed exclusively against B cells. LCT did not correlate with peripheral lymphocyte counts, antithyroglobulin or antimicrosomal antibodies, sex, age, pregnancies, thyroid status or medication. However the mean duration of the disease was 15 months in LCT positive group and 55 months in LCT negative group (p less than 0.01). Weak GCT were found in 8 of 35 sera (23%). Six of 33 sera (18%) contained cold-reacting MCT and 9 (27%) had warm-reacting MCT. Some cytotoxins were directed against several types of cells as evidenced by cytotoxicity of eluates from lymphocytes against PMN and/or monocytes. Of 23 patients with HT, 11 (48%) had cold-reacting LCT. None had warm-reacting LCT. Sera and eluates from lymphocytes showed predominant cytotoxicity toward B cells. No correlation to the presence of antibodies, sex, age, pregnancies, thyroid status or medication was detected. Four of 23 sera had weak cold-reacting GCT, 5 had cold-reacting MCT which killed on average 31% of monocytes and 4 had weak warm-reacting MCT. Twelve of 22 sera from GD and HT had cytotoxic activity against thyroid cells (TCT). TCT correlated with LCT at p less than 0.05.(ABSTRACT TRUNCATED AT 250 WORDS)

Induction of alloreactive immunosuppression by 1,4-bis [( 2-aminoethyl)amino]-5,8-dihydroxy-9,10-anthracenedione dihydrochloride (CL 232,468)

1,4-bis[2-aminoethyl)amino]-5,8-dihydroxy-9,10-anthracenedione (AEAD) has been investigated for its potential immunosuppressive effect on cell-mediated immune responses. Addition of the compound to mixed lymphocyte cultures (MLC) not only significantly inhibited these cells from responding to alloantigens but also prevented the induction of cytolytic T lymphocytes (CTL). A structurally related compound, mitoxantrone, was also found to be active in inhibiting CTL induction. AEAD had to be present during the first 3 days of a 5-day MLC in order to produce a significant effect and it had no effect on those CTL already generated, suggesting that it acted upon induction of CTL rather than the effector phase. Lymphocytes from mice treated with the compound were incapable of responding to alloantigens in vitro and the effect was dose- and time-dependent. Furthermore, lymphocytes from treated mice were found to inhibit CTL generation from normal mouse lymphocytes, indicating that a suppressor cell population might be induced in the spleens of animals treated with the compound. The present findings clearly demonstrate that AEAD is a compound with potent immunosuppressive activity on alloreactive immune responses.

Immunologic aberrations in asbestos cement workers: dissociation from asbestosis

Immunoregulatory disorders have been implicated in the pathogenesis of asbestosis. We therefore compared the immunologic status of a well-characterized group of 31 current and former asbestos-cement workers with that of a group of 52 healthy controls, after adjustments had been made for the possible confounding effects of age, race, and smoking. The asbestos workers had significantly decreased percentages and numbers of both B and T lymphocytes in peripheral blood and a paradoxical IgG hypergammaglobulinemia. Analysis of T-lymphocyte subpopulations revealed that total T-cell numbers (OKT3+), helper-inducer T-cell numbers (OKT4+), and suppressor-cytotoxic T cell numbers (OKT8+) were decreased by similar proportions. These decreases were negatively correlated with time elapsing since the end of exposure to asbestos. In both workers and controls, lymphocyte proliferative responses to phytohemagglutinin (PHA) were correlated positively with the number of OKT4+ cells and negatively with age and serum IgG levels. When adjustments had been made for these confounding variables, no differences in PHA responses were noted between workers and controls. No relationship was detected in the workers between any of the immunologic aberrations noted and (1) radiographic category of pneumoconiosis, (2) estimates of cumulative asbestos exposure, or (3) abnormalities of pulmonary function. These data suggest that the immunologic perturbations we have noted in asbestos-exposed individuals are epiphenomena, unrelated to the pathogenesis of asbestosis itself.

Circulating immune complexes in pregnancy, preeclampsia, and autoimmune diseases: evaluation of Raji cell enzyme-linked immunosorbent assay and polyethylene glycol precipitation methods

Sera from 86 individuals were tested for circulating immune complexes by the polyethylene glycol precipitation method and a Raji cell enzyme immunoassay (Raji-ELISA). These included normal nonpregnant control subjects, nonpregnant patients with autoimmune diseases, healthy women in the second and third trimesters of pregnancy, patients with preeclampsia, and women with pregnancies complicated by preexisting autoimmune diseases. Diseases such as systemic lupus erythematosus and rheumatoid arthritis were associated with increased levels of immune complexes in both pregnant and nonpregnant individuals. Circulating immune complexes were not observed in normal pregnancies or in preeclampsia. Although pregnancy itself is not an immune complex-associated state, the presence of immune complexes in autoimmune diseases may explain some of the complications observed during pregnancy in these patients.

Natural cytotoxicity in systemic lupus erythematosus: mechanisms of suppression by inhibitory serum factors

Spontaneous cytotoxicity mediated by natural killer (NK) cells is impaired in several human diseases including systemic lupus erythematosus (SLE). The present study was designed to describe factors in SLE sera which suppress the NK function of unfractionated mononuclear cells and NK enriched suspensions. NK activity was determined in 19 SLE patients and 25 normal controls by a standard chromium release assay. Sera obtained from SLE patients suppressed normal NK activity by an average of 29.4%. The presence of anti-lymphocyte antibodies (ALA) of the IgM class which were reactive with unfractionated mononuclear cells or the NK cell enriched OKM1 positive subset correlated with serum-mediated suppression. NK inhibitory SLE sera did not interfere with normal effector-target conjugate formation. These results demonstrate the modulatory effects of immune aggregates and ALA on lymphocyte function in SLE. These factors suppress NK function without evidence of lymphocyte cell death or inhibition of NK effector cell binding to tumour targets.

Natural killer cell in systemic lupus erythematosus. Defects in effector lytic activity and response to interferon and interferon inducers

Spontaneous cytotoxicity mediated by natural killer (NK) cells is impaired in several human diseases including systemic lupus erythematosus (SLE). The precise mechanism(s) by which NK activity is suppressed in patients with SLE is generally unknown. The present study was designed to focus on cellular defects per se in NK cells from patients with SLE. It was observed that the usual enhancing effect of interferon (IF) and IF inducers was markedly impaired in SLE patients. Of 24 SLE patients studied, 17 had significantly decreased NK activity relative to controls. NK activity had a significant negative correlation with clinical activity score (r = -0.56, P less than 0.005) but was not correlated with corticosteroid dose, antinuclear antibody titers, total hemolytic complement (CH50), or sedimentation rate. Furthermore, significant depressions in NK activity correlated with variations in disease activity in six patients followed serially. Depressed NK function could not be reversed by prolonged in vitro incubation at 37 degrees C or with protease treatment. Furthermore, depressed NK activity was not altered by removal of glass adherent cells nor was a suppression of NK activity in normal controls seen by the addition of SLE peripheral mononuclear cells. No reversal of depressed activity to normal levels was seen by the addition of indomethacin nor did the supernatants from SLE cell cultures cause a suppression of normal NK function. NK activity in SLE patients did not respond normally to IF inducers (poly-I:C and concanavalin A) even if the SLE patients had normal NK function. The response of SLE cells to exogenous IF was also impaired. The number of effector-target conjugates was quantitated with several target cells (K562, Yac-1, Fravel) in SLE patients and controls. A significant correlation between the proportion of glass nonadherent mononuclear cells that formed effector-target conjugates with these various targets and the magnitude of NK lysis was observed. However, SLE and normal subjects had equal numbers of effector-target conjugates independent of NK function. Release of a soluble cytotoxic factor was induced with concanavalin A, and was markedly impaired in SLE patients relative to normal controls. Thus, impaired NK cell function in SLE does not appear to be related to cell-mediated suppressive mechanisms or to the deletion of effector cells; rather, the decreased NK activity may be related to an impaired release of a soluble cytotoxic factor.

Cellular immune function in rheumatic disease

Investigation of the cellular immune function in patients with rheumatic diseases is important in elucidating the pathogenesis of the disease processes and in determining the associated abnormalities of recognition and regulation exerted by the immune system. However, because of the lack of specificity and the variations noted from laboratory to laboratory, tests of cellular immune function are, at present, of little value in the laboratory diagnosis of these diseases. The abnormalities found in the rheumatic diseases occur with many autoimmune diseases and other inflammatory states. The common pathway of immune abnormalities appears to be influenced by several factors. They include several genetic loci, possible environmental factors, and immunologic mechanisms, which appear to interact in an intimate way to induce various autoimmune diseases.

Dermatologic conditions reported in patients with rheumatoid arthritis

Dermatologists, while becoming increasingly involved in the diagnosis and management of patients with connective tissue diseases, have left rheumatoid arthritis relatively unexplored. An increased awareness of possible pathomechanisms of rheumatoid arthritis may allow for generalizations that lead to increased understanding of other connective tissue disorders. The types of cutaneous disorders that occur in association with rheumatoid arthritis include: vasoreactive dermatoses (e.g., various forms of vasculitis), which may occur secondary to the circulating immune complexes present in rheumatoid arthritis; autoimmune bullous disorders, which may occur in the setting of a suppressor T cell defect in rheumatoid arthritis; and various miscellaneous cutaneous associations. Hopefully, this review will lead to an increased understanding of both rheumatoid arthritis and the wide array of cutaneous associations of rheumatoid arthritis.

Studies of rheumatoid synovial fluid lymphocytes. II. A comparison of their behavior with blood mononuclear cells in the autologous mixed lymphocyte reaction and response to TCGF

Synovial fluid lymphocytes (SFL) and peripheral blood lymphocytes (PBL) from patients with rheumatoid arthritis were compared for their response to lectin stimulation and for their behavior in the autologous mixed lymphocyte reaction (AMLR). The SFL proliferative response to phytohemagglutinin (PHA), as measured by tritiated thymidine incorporation at 72 hr, was lower than that of PBL (P less than 0.001). When T-cell growth factor (TCGF) was added to the medium, there was an increase in the SFL proliferative response to PHA (P less than 0.05). In contrast, TCGF did not alter significantly the PBL proliferative response to PHA. Mixing experiments were performed to determine whether the poor SFL proliferative response was due to passive absorption and removal of in situ-generated TCGF by "suppressor" cells. When cultured together, SFL did not suppress the PBL proliferative response to PHA, suggesting that decreased production of TCGF rather than competitive binding of TCGF results in the poor SFL proliferative response to lectin stimulation. In the AMLR, synovial fluid non-T cells were found to be more stimulatory to peripheral blood T cells than were peripheral blood non-T cells (P less than 0.001). In comparison to peripheral blood T cells, synovial fluid T cells were poor responders in the AMLR. Repetitive in vitro autologous stimulation of peripheral blood T cells resulted in proliferative responsiveness analogous to that of SFL, i.e., a relatively poor proliferative response in the AMLR and a poor response to PHA. The latter could be augmented by TCGF. The SFL requirement for exogenous TCGF is consistent with a state of immune activation. In vivo stimulation by non-T cells may play an important role in the immune activation which characterizes rheumatoid SFL.

Analysis of depressed cell-mediated immunity in asbestos workers

To explore the mechanisms of asbestos-related perturbations of the immune system, we evaluated the in vitro cell-mediated immunity of five asymptomatic asbestos workers with hypergammaglobulinemia and decreased T-cell numbers. These results were compared with those in 10 matched controls. Analysis of T-lymphocyte populations revealed decreased absolute numbers of OKT4+ (helper/inducer) T cells in the peripheral blood and phytohemagglutinin (PHA)-stimulated mononuclear cell cultures of the workers. When chrysotile asbestos was added to PHA cultures, expansion of OKT4+ cell populations was disproportionately inhibited in workers' cultures. Furthermore, control proliferative responses to PHA became indistinguishable from initial worker responses. These effects were incompletely explained by the cytotoxic effects of asbestos on cultured lymphocytes. We conclude that both in vivo and in vitro exposure of mononuclear cell populations to asbestos may lead to a diminution of helper-inducer T-cell numbers. In asbestos-exposed individuals, this latter lymphocyte subpopulation appears to be especially sensitive to in vitro asbestos exposure. Although the clinical implications of these findings are unclear, we hypothesize that many of the immunologic abnormalities that occur in asbestos workers could be explained by direct asbestos effects on the OKT4+ immunoregulatory population.

Column separation of monocytes by adherence to gelatin beads

This investigation was performed to study whether the efficient binding of collagen to monocytes in the presence of fibronectin and heparin may be used for separation of monocytes from human peripheral blood. It was shown that monocytes adhere selectively to gelatin bead columns in the presence of fresh plasma and heparin. Mononuclear blood cells are rapidly depleted of monocytes by passage through a 5-10 ml column at a flow rate of 1.5-2.0 ml per min. Adhering lymphocytes are more loosely attached and may be detached by stirring and washing, while the monocytes can be eluted by 50 mM EDTA. This separation technique is suitable for combination with various other methods since it is rapid, allows convenient handling of large numbers and yields cells with very high viability. Although most B lymphocytes pass through the column without attaching, there is some enrichment of B cells and non-T, non-B cells among the adherent lymphocytes.

Detection of circulating immune complexes with a Raji cell enzyme immunoassay

The Raji cell assay for circulating immune complexes (CIC) is frequently the method of choice when the detection of large, complement fixing complexes is desired. We have developed an enzyme-linked immunosorbent assay modification (Raji-ELISA) of the Raji cell technique which is easy to perform, uses commercially available reagents and is more convenient than the conventional Raji cell radioimmune assay (Raji-RIA). Fourteen samples were tested by both assays and a good correlation was observed (P = 0.05). Sera from patients with suspected immune complex associated diseases were tested in the Raji-ELISA. Unsensitized Raji cells gave a value of 1.25 micrograms of immune complex associated IgG/ml. Using 2 standard deviations as a cutoff to determine positivity, 2 of 32 healthy controls (6.2%) had elevated levels of circulating immune complexes. In our study population, 9 of 23 cancer patients (39.1%), 10 of 13 patients with autoimmune diseases (76.9%), 3 of 17 patients with positive rheumatoid factor titers (17.6%), 1 of 23 pregnant patients (4.3%), 1 of 5 preeclamptic patients (20%) and 9 of 30 other patients with suspected immune complex associated diseases (30%) had elevated levels of CIC.

Relationship between reduced B cell susceptibility to IgM antibodies and reduced IgD-bearing B cells in patients with systemic lupus erythematosus

Peripheral blood lymphocytes from 14 patients with systemic lupus erythematosus, 5 patients with rheumatoid arthritis, and 10 normal subjects were cultured for 7 days with or without anti-IgM or anti-IgD antibodies, and IgG- and IgM-secreting cells were assayed by reverse hemolytic plaque assay. Surface immunoglobulin (Ig) isotypes on peripheral blood B cells were also examined by a direct anti-Ig rosetting reaction. In normal subjects and rheumatoid arthritis patients, the spontaneous development of IgG- and IgM-secreting cells was markedly suppressed by anti-IgM or anti-IgD antibodies. Over 50% of peripheral blood B cells were IgD- and IgM-bearing cells in normal subjects and in most patients with rheumatoid arthritis. In lupus patients, however, the suppression of IgG and IgM production by anti-IgM or anti-IgD antibodies was remarkably reduced, especially in the active stage. Furthermore, the percentage of IgD-bearing cells in peripheral blood B cells was remarkably reduced, especially in patients with active disease. There was a good correlation between reduced susceptibility of B cells to anti-IgM antibody-mediated suppression and reduced percentage of IgD-bearing cells in lupus patients.

Lidocaine effects on immunocompetent cells. Implications for studies of cells obtained by bronchoalveolar lavage

Immunologic data obtained from bronchoalveolar lavage (BAL) is useful for both clinical and investigative purposes. Although lidocaine, used for local anesthesia, is present in BAL in up to 12 mmol concentration, its effects on immunologic tests are unclear. The results of our study show that lidocaine has profound effects on the results of functional studies of immuno-competent cells. Care should be taken to quantify, standardize, and limit the exposure of alveolar cells to lidocaine during bronchoscopy if such studies are to be performed. However, exposure of cells for 25 minutes or less to lidocaine solutions up to 12mmol in concentration does not affect a variety of immunologic tests of interest. At the same time, carefully controlled use of lidocaine in lavage solutions significantly increases the number of cells obtained for study.

Autoimmune diseases: immunopathology and etiopathogenesis

Images

Spontaneous plaque forming cells in the peripheral blood of patients with systemic lupus erythematosus

A reverse haemolytic plaque assay using staphylococcal protein A coupled to sheep red blood cells was set up in Cunningham chambers. Using this method, the numbers of Ficoll-Hypaque isolated peripheral blood lymphocytes (PBL) secreting IgG, IgA or IgM without preceding culture or mitogen stimulation were estimated in patients with systemic lupus erythematosus (SLE) and control subjects. Seven patients with clinically inactive SLE at the time of the study had values similar to those of the control subjects. In contrast, eight patients who had clinically active SLE had markedly increased numbers of PBL secreting IgG, IgA and IgM. Control experiments confirmed that the plaques were due to Ig secretion by lymphoid cells rather than to immune complexes adsorbed onto Fc receptor bearing cells or to passively adsorbed Ig. The results confirm the expected polyclonal B cell activation in patients with SLE and serial measurements showed that clinical relapses occurred only when the numbers of immunoglobulin secreting cells were high. Experiments in three patients with active SLE using native DNA prepared from T2 bacteriophage as the 'developing antigen' suggest that PBL secreting nDNA antibody can also be demonstrated by this method.

Antibody-mediated cellular cytotoxicity against Raji cells ADCC(Raji): evaluation of false positives in the detection of circulating immune complexes by Raji-cell assay

Raji-cell radioimmunoassay is a very sensitive and reproducible method for the detection of circulating immune complexes. Using a complement-independent, antibody-dependent cellular cytotoxicity assay against 51Cr-labeled Raji cells, there is no correlation between activity against Raji cells and positivity in Raji-cell radioimmunoassay for circulating immune complexes in three sets of sera (from renal transplantation patients, multiparous women, and patients suffering from systemic lupus erythematosus). We conclude that IgG antibodies to Raji membranes are not a significant cause of false-positive results in circulating immune complexes as detected by Raji-cell radioimmunoassay.

Cell membrane markers and phytohemagglutinin reactivity of circulating lymphocytes from chronic myelocytic leukemia patients

Lymphocytes from 22 patients with chronic myeloid leukemia (CML), 13 treated with polychemotherapy, eight by monochemotherapy, and one untreated, were analyzed for the presence of classic T and B cell surface markers (E-rosette, EAC-rosette, surface immunoglobulins) and for their ability to respond to phytohemagglutinin (PHA). The absolute number and percentage of E-rosetting cells (T-cells), EAC-rosetting cells and cells staining for surface immunoglobulins (B cells) were all significantly lower than controls (P less than or equal to 0.025). The response to PHA was also significantly lower in patients than in controls at the smaller concentrations of the mitogen (3.75 micrograms/ml, 30 micrograms/ml) tested (P less than or equal to 0.01); at a higher PHA concentration (120 micrograms/ml) the decrease in PHA stimulation approached significance (P = 0.07). These lymphocyte abnormalities support the concept that CML lymphocytes may be derived from the leukemic clone.

Autoantibodies against Tmu and B lymphocytes in patients with rheumatoid arthritis

Patients with rheumatoid arthritis have decreased numbers of T mu lymphocytes in their peripheral blood. To find out whether these low number of T mu lymphocytes were associated with the presence of anti-lymphocyte antibodies, the sera of 27 patients with definite or classical rheumatoid arthritis (RA) were investigated for the presence of autoantibodies against subsets of lymphocytes. In addition the numbers of T, T mu, T gamma and B lymphocytes in the peripheral blood of these patients were investigated. Patients with active RA showed lower numbers of T mu lymphocytes in their peripheral blood than patients with inactive RA. However, both groups of RA patients had significantly decreased numbers of T mu lymphocytes in their peripheral blood as compared with 22 age matched healthy donors. Moreover, mainly in patients with active RA cold reactive antibodies were found directed against T mu and B lymphocytes, but never against T gamma lymphocytes of healthy donors. Similar results were found in the indirect immunofluorescence procedure when tested for reactivity against T-cell subsets. This serum reactivity was not caused by rheumatoid factors or antinuclear antibodies. Since RA sera after precipitation with 2.5% polyethyleneglycol, still showed cytotoxicity against T and B lymphocytes, it is suggested that this serum reactivity is not caused by immune complexes but by antibodies.

Association between endogenously activated T cells and immunoglobulin-secreting B cells in patients with active systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is characterized by increased numbers of circulating B cells activated polyclonally to secrete immunoglobulin. Because T cells secrete, or shed, various factors that are functionally important in regulating immunoglobulin production by B cells, a reverse hemolytic plaque assay was developed to quantitate such activated T cells. In this technique, we used a rabbit antiserum raised to supernatants of concanavalin-A--stimulated human lymphocytes. The relevant antigenic specificity of this antiserum is directed toward the shed surface membrane determinant(s) preferentially expressed on activated T cells. Freshly isolated peripheral blood mononuclear cells from 14 SLE patients contained more than 10 times the number of endogenously activated T cells than cells from normal subjects. Within the SLE group, plaque-forming T cells were particularly increased in patients with active disease. By linear regression analysis, a significant positive correlation was revealed between such activated T cells and immunoglobulin-secreting B cells, also measured by a reverse plaque assay (r = 0.83). It appears that both activated B cells and T cells circulate in increased numbers in SLE. Additional investigation will be required to define the molecular nature of the T cell product(s) being measured and to clarify the relationship of these findings to the immunoregulatory abnormalities in this disorder.

The in vitro effect of a calf thymus extract (thymostimulin) on the immunologic parameters of patients with untreated Hodgkin's disease

The in vitro effect of a calf thymus extract, thymostimulin (TP--1), on the E-rosette-forming capacity and on the PHA blastogenic response of peripheral blood lymphocytes was evaluated in 20 patients with untreated Hodgkin's disease. The mean percentage of lymphocytes forming E rosettes increased in patients from 44.2% to 57.5% (P less than 0.005). The mean PHA stimulation index rose with all three concentrations tested, but returned to the normal range only with the highest PHA concentration (60 mu/ml). An increase in the immune parameters was greatest in those patients who presented with decreased E-rosetting cells of total lymphocyte counts or whose disease was Stage III or IV or of mixed cellular histology.

Multiple abnormalities in immunoregulatory function of synovial compartment T cells in patients with rheumatoid arthritis. Recognition of a helper augmentation effect

Analyses of the synovial tissue and fluid T lymphocytes obtained from patients with rheumatoid arthritis revealed multiple functional defects in the regulation of autologous blood B cell differentiation into cells secreting immunoglobulin. These abnormalities were not found in peripheral blood T lymphocytes from the same patients. Although the patients selected showed elevated levels of T cells expressing the T8 differentiation antigen as well as Ia antigens there was little demonstrable suppression of the blood B cell differentiation. Furthermore, the synovial T cells exhibited only minimal helper or inducer activity when tested in the same system. In contrast, patient's blood T lymphocytes gave levels of help and suppression that were not distinguishable from that of normal individuals. Co-culture experiments of blood and synovial T lymphocytes did not reveal any evidence for enhanced suppression; indeed, in most patients these co-cultures resulted in marked augmentation of helper function, a phenomenon designated "helper augmentation". These data provide evidence that rheumatoid synovial lymphocytes are characterized by marked abnormalities in immunoregulatory T cell function, including divergence of cellular activity from the immune function predicted by surface phenotype and a capacity for "helper augmentation", a novel T cell function in man.

Failure to detect brain reactivity of lymphocytotoxins in cerebral lupus

Lymphocytotoxic activity (LCA) was examined in the sera of 29 patients with systemic lupus erythematosus (SLE), including eight with cerebral involvement. LCA was elevated in 80% of samples and was significantly higher in the group with cerebral disease (P less than 0.001). No correlations were observed between LCA and immune complexes or complement components. Sera from 10 patients (six with cerebral SLE) were absorbed with homogenates of normal human frontal cortex and liver using protein standards to control for dilutional effects. No serum sample showed selective depletion of LCA following incubation with brain homogenate. It is concluded that no single parameter, including brain absorption of LCA, is effective in monitoring disease activity in cerebral lupus.

The nature of the immunoglobulin G on the surface of B lymphocytes in chronic lymphocytic leukemia

The nature of the immunoglobulin (Ig) G found associated with the neoplastic B lymphocytes in chronic lymphocytic leukemia that also express Igm and IgD had been investigated by absorption studies using anti-idiotypic antibodies raised against cell surface IgM from five patients. In all five cases, although cellular IgM and IgD behaved as idiotypic, the IgG did not. Thus the IgG frequently found associated with lymphocytes at this stage of differentiation is likely, at least in many cases, to be of extrinsic origin.

Ia+ T cells in synovial fluid and tissues of patients with rheumatoid arthritis

Markedly elevated levels of T cells expressing Ia antigens were found in the synovial membranes and synovial fluids of patients with rheumatoid arthritis. The primary increase in expression of the Ia antigens was on the OKT 8+ (suppressor/cytotoxic) T cell subset. In addition, the total percentage of OKT 8+ T cells in intraarticular sites was usually greater than levels in peripheral blood. Small numbers of OKT 4+ (helper/inducer) cells bearing Ia antigens were also identified. The characteristic increase in the Ia+ T cells in peripheral blood was not encountered in most patients treated with D-penicillamine.

Lymphokine-mediated suppression of chondrocyte glycosaminoglycan and protein synthesis

Spontaneously released and T cell mitogen augmented lymphokine produced by human mononuclear cells has been shown to induce a concentration dependent reversible suppression of chondrocyte glycosaminoglycan and protein synthesis without significantly enhancing chondrocyte catabolic activity. The modulatory factor(s) is of T cell origin and is trypsin, pronase, and heat sensitive. Prostaglandin inhibitors failed to influence factor formation or activity. Although eluting from Sephadex G-100 over a wide range, peak activity had an approximate molecular weight of 53,000 and appeared distinct from recognized forms of lymphotoxin.