Ia specific antilymphocyte antibodies in rheumatoid arthritis

Lymphocyte function in patients with interstitial cystitis

To determine whether there is a primary immunological disorder involved in the etiology of interstitial cystitis, we compared the in vitro function of peripheral blood lymphocytes from 10 patients with interstitial cystitis to those from 10 healthy female controls. The lymphocytes were isolated and incubated in either cell culture medium alone, cell culture medium supplemented with the mitogen phytohemagglutinin or cell culture medium with autologous sterile filtered urine, the latter to detect any immunogenic potential of urine in this disease. We studied the relative proliferation of the phenotypes CD2, CD4, CD8, CD19, CD14 and CD56 by immunofluorescence and flow cytometry. To detect activation of T lymphocytes we also studied expression of HLA-Dr and interleukin-2 receptors. There was no difference in the rate of proliferation of the various lymphocyte phenotypes between the 2 groups in any of the culture media. Similarly, there was no difference between the 2 groups in the degree of lymphocytic activation after incubation. Furthermore, incubation in the presence of autologous urine caused no increase in activation above that seen in control cultures. We also assessed the production of the lymphokines interleukin-1, interleukin-2 and interferon-gamma in the supernatant fluid of the cell cultures. There was no difference in the production of these immunoregulatory cytokines between the control and patient groups, and again urine did not act as a mitogen in either group. We conclude from this study that there is no primary immunological disorder evident in patients with interstitial cystitis, and that the urine does not act as a stimulant to the immune system. This finding casts severe doubt on any theory suggesting that interstitial cystitis is an autoimmune disease or that urine contains an autoantigen causing the disease.

Impairment of helper T-cell function and lymphokine-activated killer cytotoxicity following severe head injury

Infection is a major complication of severe head injury, occurring in 50% to 75% of patients who survive to hospitalization. Previous investigations of immune activity following head injury have demonstrated suppression of helper T-cell activation. In this study, the in vitro production of interferon-gamma (INF-gamma), interleukin-1 (IL-1), and interleukin-2 (IL-2) was determined in 25 head-injured patients following incubation of peripheral blood lymphocytes (PBL's) with the lymphocyte mitogen phytohemagglutin (PHA). In order to elucidate the functional status of cellular cytotoxicity, lymphokine-activated killer (LAK) cell cytotoxicity assays were performed both prior to and following incubation of PBL's with IL-2 in five patients with severe head injury. The production of INF-gamma and IL-2 by PHA-stimulated PBL's was maximally depressed within 24 hours of injury (p less than 0.001 for INF-gamma, p = 0.035 for IL-2) and partially normalized within 21 days of injury. There was no change in the production of IL-1. When comparing the in vitro LAK cell cytotoxicity of PBL's from head-injured patients and normal subjects, there was a significant depression in LAK cell cytotoxicity both prior to (p = 0.010) and following (p less than 0.001) incubation of PBL's with IL-2. The results of this study indicate that IL-2 and INF-gamma production, normally required for inducing cell-mediated immunity, is suppressed following severe head injury. The failure of IL-2 to enhance LAK cell cytotoxicity suggest that factors other than decreased IL-2 production, such as inhibitory soluble mediators or suppressor lymphocytes, may be responsible for the reduction in cellular immune activity following severe head injury. These findings may have significant implications in designing clinical studies aimed at reducing the incidence of infection following severe head injury.

Occurrence of lymphocytotoxins in multi-case rheumatoid arthritis families: relation to HLA

The presence of lymphocytotoxic antibodies (LCA) and their association with HLA haplotypes has been studied in 27 multi-case rheumatoid arthritis (RA) families (13 multiplex and 14 simplex) in Northern India. Of the total 59 RA patients, 69.4% had cytotoxins in their sera as compared with 2.5% of healthy controls. No differences were observed in the frequency of LCA in relation to sex and rheumatoid factor. LCA against B cells were significantly more predominant than those against T cells. Twenty families studied for correlation of HLA with LCA showed greater intensity of reaction with DR4+ haplotypes, particularly in simplex families. Similarly, the frequency of LCA among patients and unaffected parents was greater in simplex compared with multiplex families. Haplotype sharing with the patient was increased in the relatives positive for cytotoxins in these families. An immunogenetic contribution made by the affected parent and a common environmental stimulus may be responsible for the increased production of LCA in multi-case families with RA.

Suppression of cellular immune activity following severe head injury

Infection is a major cause of morbidity following multiple traumatic and head injury. Although immunosuppression has been demonstrated after multiple traumatic injury, the effects of head injury on immune function have not been thoroughly investigated. In a prospective study of 10 severely head-injured patients, in vitro and in vivo parameters of cellular immune activity were assessed. In vitro measurements of lymphocyte surface antigen expression following mitogen stimulation were made serially over a 3-week period in 10 patients with severe head injury. The control group consisted of 20 healthy subjects. Phenotyping of peripheral blood lymphocytes (PBLs) was performed following incubation with and without mitogens. Phenotypes were determined by flow cytometry using monoclonal antibodies (MABs) to T lymphocyte subsets and the alpha subunit of interleukin 2 (IL-2) receptors. In vivo cellular immune function was determined by measuring patient responses to delayed-type hypersensitivity (DTH) skin testing within 24 h of injury. When head-injured patients were compared to controls, PBLs incubated in the presence of phytohemagglutinin (PHA) demonstrated a decrease in cells marking as T cells (p = 0.005), helper-inducer T cells (p = 0.001), and in the number of IL-2 receptor-bearing cells (p = 0.001). The functional ability of these lymphocyte subpopulations to proliferate in the presence of PHA was significantly suppressed within 24 h of injury and normalized within 3 weeks of injury. DTH skin testing to Candida, mumps, trichophyton, and PPD antigens was performed within 24 h of injury and resulted in anergic responses in all 10 patients when measured at 24, 48, and 72 h following administration. The overall infection rate was 60%, with the majority of infections occurring within the first 4 days following injury. The results of this study indicate that severe head injury results in suppression of cellular immune function with a corresponding high rate of infection. The possible significance of the decrease in the percentage of helper-inducer T cells and in the number of cells bearing IL-2 receptors following mitogen stimulation is discussed.

Network regulation in rheumatoid arthritis. Studies of DR+ T cells, anti-DR, antiidiotypic antibodies, and clinical disease activity

We prospectively studied rheumatoid arthritis patients with various degrees of clinical disease activity, for the presence of DR+ T cells by flow cytometry, for anti-DR using immunoblot analysis, and for antiidiotypic (anti-id) antibodies by enzyme-linked immunosorbent assay using F(ab')2 monoclonal antibody anti-DR L243 as idiotype. DR+ T cells correlated positively with anti-DR, and anti-id correlated negatively with both DR+ T cells and anti-DR. Active clinical disease correlated positively with both DR+ T cells and anti-DR, and correlated negatively with anti-id. This DR antigen/anti-DR/anti-id network may control disease activity in rheumatoid arthritis patients.

Autoantibodies from rheumatoid arthritis patients recognize antigens on the synoviocyte surface

We have found autoantibodies in the sera from rheumatoid arthritis (RA) patients which recognize two cell surface antigens of approximately 70 kDa and 28 kDa from synoviocyte extracts as detected by immunoprecipitation analysis. These polypeptides were immunoprecipitated from extracts containing mainly macrophage-like synoviocytes (type A) but not from extracts of homogeneous fibroblast-like synoviocytes (type B). These autoantigens are not selectively expressed by RA synoviocytes, since both RA and non-rheumatoid synovia were reactive for RA sera. From the panel of different RA sera tested, 64% immunoprecipitated the 70 kDa band, and 27% recognized the 28 kDa polypeptide. These differences in the specificity of the sera seemed to be related to the clinical state of the donor. The sera from patients suffering from other autoimmune diseases such as autoimmune thyroiditis and systemic lupus erythematosus (SLE) do not appear to be reactive for these specificities, but sera from patients with Sjögren's syndrome, psoriatic arthritis, and Crohn's disease showed a weak cross-reactivity with the 70 kDa polypeptide. This autoreactivity against synovial cells in RA supports the idea that these cells participate in the initial immune response of the disease.

Isotype and cytotoxicity spectra of anti-lymphocyte antibodies in patients with systemic lupus erythematosus

IgG anti-lymphocyte antibodies (ALA) reactive with resting lymphocytes were demonstrated in sera of patients with systemic lupus erythematosus (SLE) by immunofluorescence and flow cytometry and were shown (i) to bind T cells by non-Fc receptor-related mechanisms, (ii) to potentiate antibody-dependent cellular cytotoxicity (ADCC) of lymphocytes in vitro which correlated with binding to T cells, and (iii) to occur at a similar frequency in 29 SLE sera (56%) as IgM ALA (59%). IgG ALA levels in sera negatively correlated with absolute numbers of circulating lymphocytes in patients (r = -0.48, P less than 0.05), as did IgM ALA levels (r = -0.54, P less than 0.05); however, a stronger correlation resulted when levels of both ALA isotypes were considered together (r = -0.61, P less than 0.01). Different groups of SLE patients were distinguished with respect to relative serum content of IgM and IgG ALA and corresponding serum capacity to predominantly mediate ADCC, complement-dependent cytotoxicity (CDC), or both. No correlation existed between serum ADCC and CDC activities in vitro (r = 0.22). However, SLE patient lymphocyte counts negatively correlated with ADCC (r = -0.59, P less than 0.01) and to a lesser but still significant extent with CDC (r = -0.47, P less than 0.05). The latter results suggested that ADCC, induced by serum IgG ALA, was a mechanism of cytoloysis which occurred independently of CDC and which, like CDC, was significantly associated with lymphopenia in vivo.

Anti-idiotypic antibodies to anti-DR in patients with rheumatoid arthritis

Rheumatoid arthritis (RA) sera were evaluated for anti-idiotypic (anti-id) antibodies to HLA-DR antigens (anti-DR) using an ELISA method with murine monoclonal anti-DR antibody-coated microtiter plates incubated serially with either normal or RA sera and peroxidase-conjugated goat anti-human IgG (Fc specific). Specificity was examined using other monoclonal antibodies including anti-Leu 3a, OKM5, OKT8, anti-cytochrome c, and anti-breast tumor antigen. Significant binding of 11/33 (33%) RA to anti-DR was found compared with 0/44 normals (P less than 0.001). Two groups were identified: RA sera reacting with anti-DR and anti-Leu 3a and sera which did not bind to anti-DR but bound to irrelevant monoclonal antibodies. Anti-DR reactivity was differentiated from anti-Leu 3a by competitive inhibition studies. Binding of whole sera and IgG from RA patients to anti-DR was significantly inhibited by DR+ cell extract. The same extract was not inhibitory after selective removal of DR antigen by adsorption on an anti-DR-Sepharose column. These data suggest that anti-id antibodies are directed against the antigen-binding site of id. We conclude that some RA patients have anti-id antibodies potentially involved in immunoregulation of anti-DR antibodies.

Impaired killer cell generation in the autologous mixed leukocyte reaction by rheumatoid arthritis lymphocytes

Natural killer-like cells are generated along with interleukin-2 (IL-2) in the autologous mixed leukocyte reaction (AMLR). Patients with active rheumatoid arthritis (RA), but not those whose disease is in remission, are poor producers of AMLR killer cells. This defect cannot be explained by age, medications, or serum factors. The impaired generation of natural killer-like cells was not influenced by gamma-interferon but could be partially restored by addition of indomethacin to the AMLR culture, or by culturing RA T cells with exogenous IL-2. However, the response of RA T cells to IL-2 was significantly less than that of controls. These results suggest that the defect in the generation of AMLR killer cells in patients with active RA may be due in part to defective production of IL-2 and a lesser sensitivity of RA T cells to IL-2.

Rheumatoid arthritis and cancer studies based on linking nationwide registries in Finland

Two separate registries that cover the whole population of Finland have been linked in order to study the occurrence of cancer in patients with rheumatoid arthritis. The two registries involved were the Social Insurance Institution's Population Register, which collects information on medication for certain chronic diseases since 1967 including rheumatoid arthritis, and the Finnish Cancer Registry, which has data on all cancer patients in Finland since 1953. The 213,911 person-years' follow-up of 46,101 individuals with rheumatoid arthritis revealed 1,202 cases of cancer. The relative risk of cancer was 1.15 in males and 1.01 in females. The observed number of cases significantly exceeded that expected in Hodgkin's disease, non-Hodgkin's lymphomas, multiple myeloma, and leukemia. In general, the incidence of epithelial tumors was as expected. These findings were further supported by studying the occurrence of subsequent new primary cancers among patients with rheumatoid arthritis and cancer.

Multiple tumor incidence in patients with rheumatoid arthritis or allied disorders

The incidence of multiple malignant neoplasms in 55,279 patients with rheumatoid arthritis (RA) or allied disorders was studied by linking two separate nationwide data registers covering the whole Finnish population. The linking of the Social Insurance Institution's Population Register and the Finnish Cancer Registry resulted in 2106 cancer patients in whom both cancer (diagnosed in 1967-1978) and rheumatoid arthritis or allied disorders (diagnosed before cancer) were diagnosed. In 1974, the allied disorders (ankylosing spondylitis or systemic connective tissue diseases) accounted for 3.9% of all the diagnoses in the Social Insurance Institution's Population Register. The incidence of multiple neoplasms was slightly but not significantly higher in cancer patients with RA or allied disorders than in the general population or in all cancer patients taken together. The risk of leukemia was four times higher in the rheumatoid or allied disease cancer patients than in all the cancer patients. The results are consistent with previous results showing that the leukemia incidence in RA patients is higher than expected.

Characterization of the defective autologous mixed lymphocyte response in rheumatoid arthritis

In order to characterize the autologous mixed lymphocyte response (AMLR) in patients with rheumatoid arthritis (RA) and to define the relationship with disease activity, peripheral blood T lymphocytes were stimulated with either a B lymphocyte-enriched (B cells) or a macrophage-enriched (macrophages) population. A significant reduction (P less than 0.01 to P less than 0.001) of T cell proliferation stimulated both by B cells and macrophages was observed in patients with active disease. The B lymphocytes were significantly less stimulatory (P less than 0.02 to P less than 0.001) than macrophages in the patients compared with the controls. In the normal controls, macrophages in higher concentrations were capable of suppressing the B lymphocyte-stimulated AMLR, but macrophages from patients with RA were not excessively suppressive. A significant association (P less than 0.02) was observed between disease activity and the AMLR. Using the B-enriched population, the AMLR proliferative response was significantly associated (P less than 0.001) with the production of interleukin-2. Defects in proliferation could only be partially restored by the addition of interleukin-2. These data indicate that the defective AMLR observed in patients with RA is related to disease activity and is associated with altered cellular interactions among T lymphocytes, macrophages, and the B lymphocyte-enriched population.

Lymphocyte sub-population counts after a single 40 mg administration of piroxicam in 20 patients with rheumatoid arthritis. A placebo-controlled study

Patients with active rheumatoid arthritis are characterized by a decrease in the number of circulating T-suppressor lymphocytes (identified by OKT8), resulting in an imbalance between helper (identified by OKT4) and suppressor cells. Piroxicam is a non-steroidal anti-inflammatory agent which modulates lymphocytic functions, especially by reducing the concentration of the rheumatoid factor in vitro and in vivo. A double-blind placebo-controlled study was performed in 20 patients suffering from active RA to investigate the acute effect of a single administration of piroxicam 40 mg on the number of circulating OKT3, T4, T8 and IA1 positive cells. Blood samples were obtained 16 hours before and 0, 2, 6, 8, 24, 48, and 72 h after administration of piroxicam or placebo. There was a significant decrease (P less than 0.05) in T4/T8 cell ratio 48 and 72 h after piroxicam, whereas placebo had no effect. There were no significant changes in absolute numbers of total T-lymphocyte (OKT3 positive cells), T-helper-inducer (OKT4 positive cells) and T-suppressor cytotoxic lymphocytes (OKT8 positive cells). The number of IA1 positive cells (B-cells and activated T-lymphocytes) was significantly higher in the afternoon samples (at 14.00 and 16.00 hours) than in the morning samples (at 08.00 and 10.00 hours) after both placebo and piroxicam administration (P less than 0.05). These data show that piroxicam decreases the T4/T8 cell ratio in active RA, but only 48 h after the first administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of monoclonal antibodies against lymphocyte surface antigens on interleukin 2 excretion by Epstein-Barr virus-specific human T-cell hybridomas

Monoclonal antibodies were used as probes to study the role of cell surface antigens in the response of Epstein-Barr virus (EBV)-specific human T-T hybridomas to autologous EBV-infected B lymphoblasts. Somatic cell hybrids were generated by fusing EBV-primed peripheral blood T lymphocytes with a mutant clone of the JM human T-lymphoblastoid-cell line. When exposed to autologous EBV-infected B lymphoblasts, the resulting hybrid clones released Interleukin 2 into the culture medium. Incubation of the EBV-infected B cells with two monoclonal antibodies against human Ia-like molecules blocked their ability to trigger the hybridomas. Under the same conditions, monoclonal antibodies against beta 2-microglobulin, and a 45,000 MW surface antigen common to EBV-infected B lymphoblasts, did not alter the capacity of the B cells to stimulate the hybridomas. None of four monoclonal antibodies against surface antigens on the T-cell hybridomas impaired their responsiveness to EBV-infected B lymphoblasts. These results suggest the possibility that naturally occurring or exogenously administered antibodies against Ia molecules might interfere with T-cell regulation of EBV-induced B-cell activation.