Isolation of CD4- CD8- mycobacteria-reactive T lymphocyte clones from rheumatoid arthritis synovial fluid

The majority of peripheral T cells express a heterodimeric, alpha/beta T-cell receptor, which recognizes specific antigenic peptides bound to self major histocompatibility complex (MHC) molecules, and either the CD4 or CD8 surface markers. An additional subset of T cells, whose physiological function is unknown, express a distinct CD3-associated receptor composed of gamma and delta chains. This subset includes cells lacking both CD4 and CD8 surface markers, which may be involved in autoimmunity. The recognition specificity of the gamma/delta receptors is not well characterized and has been defined in only one case to date, a murine cell line which shows MHC-linked specificity. In this report, we describe the isolation of CD4- CD8-, gamma/delta TCR bearing T cell clones from the synovial fluid of a rheumatoid arthritis patient. These T cell clones respond specifically to mycobacterial antigens without MHC restriction.

Arthritis induced by a T-lymphocyte clone that responds to Mycobacterium tuberculosis and to cartilage proteoglycans

Adjuvant arthritis characterized by chronic inflammation of the joints of rats is induced by immunization to Mycobacterium tuberculosis. To learn how autoimmune arthritis may be caused by a microbial antigen, we isolated a T-lymphocyte clone specific for M. tuberculosis antigens that was strongly arthritogenic. We now report that the clone recognized, in addition to M. tuberculosis antigens, antigens present in human synovial fluid, medium of chondrocyte cultures, and proteoglycans purified from cartilage. These observations indicate that the target antigen for the arthritogenic clone resides in the proteoglycan component of cartilage. As this arthritogenic clone shows specificity for both a M. tuberculosis antigen and a cartilage constituent we conclude that disease is probably caused by antigenic cross-reactivity. Thus, an autoimmune disease may be triggered by structural mimicry between antigens in the environment and self-antigens in the individual.

Lines of T lymphocytes induce or vaccinate against autoimmune arthritis

The pathophysiology of autoimmune arthritis was studied by selecting and isolating lines of effector T lymphocytes from rats administered an arthritogenic dose of Mycobacterium tuberculosis in complete Freund's adjuvant to induce adjuvant arthritis. Irradiated rats were intravenously inoculated with a cell line characterized by proliferative reactivity to Mycobacterium tuberculosis and, to a lesser degree, to rat collagen type II. This produced arthritis in all the irradiated rats. Nonirradiated recipients failed to develop arthritis. However, such rats, and those recovering from cell-mediated arthritis, were resistant to subsequent attempts to induce adjuvant arthritis. Lines of T lymphocytes selected for responsiveness to other antigens had no effect. Therefore, a line of T lymphocytes responsive to bacteria or to collagen type II could either induce autoimmune arthritis or serve as an agent of vaccination against it.

Arthritis induced in rats by cloned T lymphocytes responsive to mycobacteria but not to collagen type II

We have been studying the pathogenesis of adjuvant arthritis in rats using a long-term cell line of T lymphocytes, the A2 line, which can induce polyarthritis and can also be used to vaccinate rats against adjuvant arthritis. Although line A2 was selected for its proliferative response to mycobacteria, it also responded to collagen type II. To elucidate its role of responsiveness to collagen type II and the relationship between arthritogenicity and vaccination, we cloned A2 and selected a subline A2b. We now report that subline A2b, which bore a marker of helper/delayed hypersensitivity T lymphocytes, was strongly arthritogenic, but could not vaccinate against arthritis. Moreover, A2b showed no response to collagen type II. Therefore, reactivity to collagen type II is not a requisite for arthritogenicity, and mediation of arthritis and vaccination can be distinct properties of different populations of T lymphocytes.

T lymphocytes of rheumatoid arthritis patients show augmented reactivity to a fraction of mycobacteria cross-reactive with cartilage

An acetone-precipitable fraction of Mycobacterium tuberculosis cross-reacts with human cartilage. Immune responses to this antigen were assessed in 34 patients with rheumatoid arthritis, 16 patients with degenerative joint disease, and 15 healthy controls. The RA patients differed from the other two groups in having more pronounced T lymphocyte responses to the antigen; their serum antibody levels were not higher. The responses of RA patients varied with duration of disease. In the first year (7 patients) T lymphocyte reactivity was increased in the synovial exudates of affected joints but not in peripheral blood, whereas the 19 with disease of 1-10 years' duration showed high reactivity in peripheral blood; in the 8 with disease for more than 10 years, lymphocyte reactivity did not differ from that in the patients with degenerative joint disease or the healthy controls. The observation that the three groups did not differ in their responses to streptococci and a T-cell mitogen indicates that reactivity of the RA patients to the mycobacterial fraction was specific. These results raise the possibility that bacterial antigens cross-reactive with cartilage proteoglycans may be relevant to the pathogenesis of RA.

T lymphocyte lines producing or vaccinating against autoimmune encephalomyelitis (EAE). Functional activation induces peanut agglutinin receptors and accumulation in the brain and thymus of line cells

We studied lines of rat T cells, specifically reactive against myelin basic protein (BP), that were functional in mediating autoimmune encephalomyelitis or in vaccinating rats against induction of active EAE. Herein we report that these functions depended on activation of the cells by incubation with BP or with a T cell mitogen prior to inoculation into recipient rats. Activation was accompanied by the exposure of membrane-binding sites specific for the lectin peanut agglutinin. Accumulation of activated line cells in the central nervous system and thymus gland was observed.

Expression of perforin and serine esterases by human gamma/delta T cells

gamma/delta T cells have recently been described in association with a number of disorders, including autoimmune diseases. gamma/delta T cells are thought to play a cytotoxic role, but their mechanism of action is not known. Several granule mediators of cytotoxicity, including a pore-forming protein (perforin), and a family of serine esterases, have been isolated from cytotoxic T lymphocytes (CTL), lymphokine-activated killer (LAK) cells, and natural killer (NK) cells. We demonstrate here that gamma/delta T cells also express these mediators. Northern blots show that gamma/delta T cells express perforin, serine esterase 1 (SE 1), and SE 2. Three polyclonal antisera - raised against murine perforin, a peptide composed of amino acids 1-34 of human perforin, and human peforin expressed in bacteria - all reacted with a 70-kD protein in gamma/delta T cells on Western blots. Immunostaining with antiperforin antisera shows that primary gamma/delta T cells also contain perforin. Electron microscopy reveals that the granules of gamma/delta T cells resemble those of CTL, LAK, and NK cells. Gamma/delta T cells also resemble LAK cells in possessing inclusion bodies in their nuclei. These results imply that gamma/delta T cells resemble other cytolytic lymphocytes in their mechanism of action.

Dual antigenic recognition by cloned human gamma delta T cells

The function of gamma delta T cells is still elusive. The nature of the antigens that they recognize and the mode of presentation of these antigens are largely unknown. The majority of human peripheral gamma delta T cells bear a V gamma 9/V delta 2 T cell receptor, and display nonclonal reactivity to mycobacteria, without restriction by MHC. It is unknown whether these cells have clonal antigenic specificity as well. Here we describe rheumatoid arthritis-derived V gamma 9/V delta 2 T cell clones, displaying dual antigenic recognition: a nonclonal, MHC-unrestricted recognition of mycobacteria, and a clonal recognition of a short tetanus toxin peptide presented by HLA-DRw53, a nonpolymorphic class II MHC molecule associated with susceptibility to rheumatoid arthritis. This is the first evidence that V gamma 9/V delta 2 T cells can recognize nominal antigenic peptides presented by class II MHC molecules. These results suggest that much like alpha beta T cells, V gamma 9/V delta 2 cells may contribute to the immune response against foreign antigens in an antigen-specific and MHC-restricted manner. The reactivity of these gamma delta T cells to mycobacteria may represent a superantigen-like phenomenon.

Immunospecific inhibition of nerve conduction by T lymphocytes reactive to basic protein of myelin

Experimental autoimmune encephalomyelitis (EAE) induced by immunization to the basic protein of central nervous system myelin (BP) is a paralytic disease in which T lymphocytes attack the individual's own central nervous system. As the target is in white matter, EAE has been considered an experimental model of some aspects of human disease such as multiple sclerosis. To investigate whether autoimmune T lymphocytes could produce paralysis, we studied the effects on the electrophysiology of isolated nerves produced by T-lymphocyte lines reactive specifically to BP or other antigens. We now report that propagation of action potentials evoked by electrical stimulation was blocked by incubating optic nerves with specific anti-BP T cells. This blockade could be reversed for up to two hours by removing the anti-BP line cells from the optic nerve. The anti-BP line cells had no effect on conduction along allogeneic optic nerves or syngeneic peripheral nerves. This indicates that disruption of the function of myelin in neuroimmunological disease may result from an immunologically specific interaction between autoimmune T lymphocytes and myelin antigens.

Mechanisms of immune injury in rheumatoid arthritis: evidence for the involvement of T cells and heat-shock protein

Evidence for the involvement of T cells, especially CD4+ T cells, in the pathogenesis of RA is substantial and includes 1) the correlation between prolonged CD4+ T-cell depletion and improvement in joint disease in the absence of observable changes in the levels of autoantibodies (rheumatoid factors) in the blood and joints, 2) the infiltration of the inflamed synovial tissues with T cells and, 3) the increased susceptibility of individuals to RA with certain HLA-DR haplotypes. The most direct evidence for the involvement of CD4+ T cells is provided by recent studies which demonstrate rapid improvement in the joint disease manifestations of RA following the infusion of anti-CD4 monoclonal antibodies (Herzog et al. 1989, Walker et al. 1989). It is unlikely that T cells alone are responsible for the joint injury in RA. Autoantibodies (rheumatoid factors) in the joint which contribute to the release of complement breakdown products, and to the secretion of cytokines such as IL-1 by macrophages must also play an important role. Indeed, depletion of CD4+ cells after TLI or therapy with monoclonal antibody reduces, but does not eliminate, joint disease activity. The residual joint disease activity is probably influenced by the continued contribution of autoantibodies to joint injury. Production of these autoantibodies may not be dependent on help from CD4+ cells, since little change is observed in autoantibody levels after CD4+ cell depletion. The mechanisms by which T cells mediate to the joint disease in RA are not clear. Little or no direct evidence of cytotoxic effects of T cells on autologous joint cells has been reported. Considerable evidence suggests that at least some T-cell cytokines (i.e., TNF alpha, IL-6) can contribute to the proliferation of synovial lining cells which results in the marked build-up of inflammatory tissue (pannus) in the joints of patients with RA (Firestein et al. 1990). In addition, T cells may recruit other joint cells, such as macrophages, to secrete cytokines (i.e., IL-1) which both contribute to synovial cell proliferation, and cartilage and bone degeneration. The marked reduction in the spontaneous secretion of IL-1 by synovial biopsies, and improvement in disease activity after TLI support this notion. Interestingly, the CD4+ T-cell lymphokines, IL-2 and IFN-gamma, were not spontaneously secreted in detectable quantities by synovial biopsies. This suggests that the pattern of lymphokines secreted by T cells in the joint in RA are not typical of that in delayed-type hypersensitivity reactions.(ABSTRACT TRUNCATED AT 400 WORDS)

T lymphocyte lines induce autoimmune encephalomyelitis, delayed hypersensitivity and bystander encephalitis or arthritis

Lines of rat T lymphocytes responsive to the basic protein of myelin (BP) or to the purified protein derivative of Mycobacterium tuberculosis (PPD) were inoculated i.v. into recipient rats. As reported previously, the anti-BP line cells, but not the anti-PPD line cells spontaneously accumulated in the central nervous system and caused encephalomyelitis. However, the anti-PPD line cells could be induced to enter the brain and cause bystander encephalitis by intracerebral inoculation of PPD. Anti-PPD or anti-BP line cells could mediate delayed-type hypersensitivity skin reactions or bystander arthritis elicited by specific antigen. The lines did not cause specific cytolysis in vitro. Susceptibility to delayed-type hypersensitivity or bystander disease was long lasting in rats inoculated with anti-PPD line cells, while rats inoculated with anti-BP line cells were susceptible for only a few days. Thus, lines of T lymphocytes can mediate a variety of pathological reactions directed by the presence of specific antigen, self or foreign.

MHC-independent presentation of mycobacteria to human gamma delta T cells

The majority of human peripheral gamma delta T cells express antigen receptors using the V gamma 9 and V delta 2 gene products. Cells of this subset have been previously shown to uniformly recognize mycobacteria regardless of their V-(D)-J junctional sequences in an MHC-unrestricted manner. This reactivity superficially resembles activation of alpha beta cells by bacterial superantigens, which are thought to be presented by monomorphic regions of MHC class II molecules. It is not known whether presentation of the mycobacterial antigen to V gamma 9/V delta 2 T cells is also mediated by class II MHC molecules. In order to examine the similarity between presentation of bacterial superantigens to alpha beta T cells and the presentation of mycobacteria to gamma delta T cells we have studied the role of class II MHC molecules in presentation of the mycobacterial antigen AP-MT to V gamma 9/V delta 2 clones. Activation of gamma delta T cells by AP-MT required direct contact with antigen presenting cells, indicating that an interaction with cell surface molecules on antigen presenting cells is required. Class II MHC molecules were neither sufficient nor necessary for effective presentation of AP-MT to the gamma delta T cells, as transfectants expressing class II MHC molecules were unable to present, whereas cell lines lacking expression of MHC class II molecules could present this mycobacterial antigen.(ABSTRACT TRUNCATED AT 250 WORDS)

Expansion of mycobacterium-reactive gamma delta T cells by a subset of memory helper T cells

Human gamma delta T cells expressing the V gamma 9/V delta 2 T-cell receptor have been previously found to proliferate in response to certain microorganisms and to expand throughout life, presumably because of extrathymic activation by foreign antigens. In vitro expansion of V gamma 9/V delta 2 cells by mycobacteria has been previously shown to be dependent on accessory cells. In order to gain an insight into the mechanisms involved in the expansion of these cells, we have undertaken to identify the peripheral blood subset of cells on which proliferation of V gamma 9/V delta 2 cells in response to mycobacteria is dependent. Contrary to their role in antigen presentation to alpha beta T cells, professional antigen-presenting cells, such as monocytes, B cells, and dendritic cells, were unable to provide the cellular support for the expansion of V gamma 9/V delta 2 cells. Selective depletion of T-cell subsets, as well as the use of highly purified T-cell populations, indicated that the only subset of peripheral blood cells that could expand V gamma 9/V delta 2 cells were CD4+ CD45RO+ CD7- alpha beta T cells. These cells underwent distinct intracellular signaling events after stimulation with the mycobacterial antigen. Expansion of V gamma 9/V delta 2 cells by alpha beta T cells was dependent on cell-cell contact. This is the first evidence that a small subset of the memory helper T-cell population is exclusively responsible for the peripheral expansion of V gamma 9/V delta 2 cells. These data illustrate a unique aspect of antigen recognition by gamma delta T cells and provide new means to study their immune defense role.

Histopathology of arthritis induced in rats by active immunization to mycobacterial antigens or by systemic transfer of T lymphocyte lines. A light and electron microscopic study of the articular surface using cationized ferritin

We analyzed the histopathologic findings of arthritis in 3 rat models: adjuvant arthritis induced by active immunization to Mycobacterium tuberculosis (MT) antigens, arthritis produced by passive transfer of an intrinsically arthritogenic line of anti-MT T lymphocytes, and bystander arthritis produced by intraarticular injection of a foreign antigen, ovalbumin, into rats with T lymphocyte line cells specific for the ovalbumin antigen. The histopathology of the tibiotarsal and knee joints was studied by light microscopy and the articular surface of the cartilage by electron microscopy after labeling with cationized ferritin. The lesions in the 3 models of arthritis were compared. In active adjuvant arthritis, inflammatory lesions and cartilage destruction were found as early as 9 days after immunization, and persisted for as long as 11 months. Similar, but somewhat milder, lesions were found in arthritis produced by transfer of anti-MT T lymphocytes. Inflammatory signs were present at 4 days, when there was no evidence of joint edema. Severe inflammatory lesions were found in arthritis induced by transfer of anti-ovalbumin T lymphocytes that was followed by ovalbumin injection into the knee. Pathologic changes were found to be similar in all 3 models. Thus, the changes could be attributed to the action of T lymphocytes, irrespective of whether the target antigen was intrinsic to the joint.

Role of the thymus in induction and transfer of vaccination against adjuvant arthritis with a T lymphocyte line in rats

Adjuvant arthritis is an experimental disease of rats induced by immunization to antigens of Mycobacterium tuberculosis. Our observation that arthritis could be induced in irradiated rats by the A2 line of T lymphocytes in the absence of mycobacterial antigens suggested that adjuvant arthritis is an autoimmune disease. Moreover, the A2 line could be used to vaccinate unirradiated rats against the subsequent induction of adjuvant arthritis by active immunization to Mycobacteria. In the present study we found that thymus cells obtained from A2 vaccinated rats could transfer resistance to adjuvant arthritis to naive rats. This indicates that the mechanism of resistance induced by A2 vaccination is probably immunological and involves thymus-derived lymphocytes.

Listeria monocytogenes pericarditis in a chronically hemodialyzed patient

We describe the third documented case of Listeria monocytogenes pericarditis. This occurred in a 54-year-old woman with end-stage renal failure on chronic hemodialysis. Her initial presentation was one of Listeria monocytogenes bacteremia, which apparently responded to two weeks of cefazolin sodium therapy. After cessation of therapy the patient returned with Listeria monocytogenes pericarditis, this responding completely to four weeks of erythromycin therapy. We could not rule out coexisting endocarditis, especially since we found high levels of circulating immune complexes which subsided as the patient's condition improved. Further immunological studies displayed a decrease in cellular functions. This case illustrates the importance of Listeria monocytogenes as a human pathogen in immunocompromised patients. Listeria should be included among the potential causative agents of pericarditis in such patients.

T lymphocyte-synovial fibroblast interactions induced by mycobacterial proteins in rheumatoid arthritis

An in vitro system was established in which single-cell suspensions of lymphocytes and synovial cells from the joints of patients with rheumatoid arthritis were cultured and produced an outgrowth of an organized inflammatory tissue with an extracellular matrix and capsule. The tissue outgrowth, which had histologic features of pannus, required the addition of mycobacterial antigen and interleukin-2 to the tissue culture medium and was dependent upon the presence of T lymphocytes and their interaction with synovial fibroblasts.

Induction of the autoantigen proliferating cell nuclear antigen in T lymphocytes by a mycobacterial antigen

Mycobacteria have been implicated in the pathogenesis of autoimmunity. To determine the potential effect of mycobacterial antigens on peripheral blood mononuclear cells (PBMC), we analyzed PBMC incubated with the acetone-precipitable fraction of Mycobacterium tuberculosis (APMT) for changes in cellular protein expression. Two-dimensional gel analysis showed induction of a 36-kD polypeptide identified as proliferating cell nuclear antigen (PCNA), a known autoantigen, after incubation with AP-MT. PCNA plays a role in cell proliferation and is expressed as a late growth regulated factor. However, its synthesis in response to AP-MT was induced as an early event. The early induction of PCNA was regulated at a posttranscriptional level and was restricted to T cells. Treatment of PBMC with known T cell mitogens, namely PHA, anti-CD3 antibodies, and staphylococcal superantigens failed to induce an early PCNA increase. The distinct characteristics of the AP-MT effect on PCNA expression suggest a separate mechanism of induction in response to AP-MT, compared with the late increase observed in response to mitogens. The induction of PCNA in response to mycobacterial antigens may represent a pathogenically relevant mechanism in autoimmunity.

Activation of human T cell clones through the UM4D4/CDw60 surface antigen

UM4D4 is a recently defined antigen that is expressed on approximately 25% of peripheral blood T cells, but on the majority of T cells in inflammatory synovial fluid. Anti-UM4D4 activates peripheral blood T cells in the presence of accessory cells and/or phorbol ester. UM4D4 has been assigned to a new antigen cluster termed CDw60. The present study examined the ability of anti-UM4D4 to activate T cell clones derived from the synovial fluid of patients with rheumatoid arthritis. UM4D4 was expressed at varying levels on both lectin-generated and antigen-specific clones, including clones of CD4+, CD8+, and CD4-CD8- phenotypes. Anti-UM4D4 used in soluble form as a single stimulus was typically mitogenic for the CD4+ and some of the CD8+ clones, but not for the CD4-CD8- clones. Phorbol ester boosted the response to anti-UM4D4 in some clones, had no effect in others, and diminished the responses in some cases. In contrast to anti-UM4D4, anti-CD3 was generally not mitogenic in soluble form, although it was mitogenic when conjugated to beads. The data show that T cell clones derived from an inflammatory T cell infiltrate can be readily activated through the UM4D4/CDw60 antigen.

Heterogeneous effects of IFN-gamma in adjuvant arthritis

In an attempt to evaluate the role of IFN-gamma in autoimmune arthritis, we tested the effects of IFN-gamma and anti-IFN-gamma mAb (DB-1) in various phases of arthritis development in a rat model for rheumatoid arthritis; the adjuvant arthritis (AA) model, induced by immunization with CFA. In addition, the effects of IFN-gamma were tested in vitro on T cell clones derived from rats afflicted with AA. T cell clone A2b, which has been shown to be arthritogenic secreted low amounts of IFN-gamma and its Ag-specific proliferation was inhibited by IFN-gamma. In contrast, clone A2c, which can inhibit the development of AA, produced high amounts of IFN-gamma and its proliferation was increased by IFN-gamma. In vivo administration of IFN-gamma 24 h before CFA caused an enhancement of arthritis, whereas giving IFN-gamma 24 to 48 h after CFA suppressed the disease. Administration of IFN-gamma between day +4 to +12 or between day +12 to +24 increased the severity of the first phase of the disease, but had no effect later. Administration of DB-1 1 to 2 days before adjuvant or between day +4 to +8 substantially decreased the disease, whereas DB-1 given from day +12 to +24 significantly enhanced it. Taken together, these results illustrate the heterogeneity of IFN-gamma in autoimmune arthritis and suggest a rational explanation for the possibly conflicting reports regarding the role(s) and effects of IFN-gamma in autoimmune processes. The multistage nature of T cell-mediated autoimmune arthritis may be due to the predominance of distinct T cell populations at different stages of the disease. The differences in the biologic activities of these T cells may be due to their patterns of lymphokine production.

Autoimmune encephalomyelitis (EAE) mediated or prevented by T lymphocyte lines directed against diverse antigenic determinants of myelin basic protein. Vaccination is determinant specific

Lines of T lymphocytes reactive against the basic protein of myelin (BP) were found in previous studies to mediate experimental autoimmune encephalomyelitis (EAE) in rats. Moreover, inoculation of rats with attenuated anti-BP line cells vaccinated them against subsequent attempts to induce active EAE by injection of BP in adjuvant. In the present study, we investigated the effects of T lymphocyte lines reactive to different antigenic determinants on the BP molecule, they are the major encephalitogenic peptide (EP) determinant present on guinea pig BP (G-BP), and minor, non-EP determinants present on bovine BP (B-BP). We found that both lines of T lymphocytes could mediate EAE. Resistance to active EAE acquired by spontaneous recovery from line mediated EAE or by vaccination with attenuated cells, however, was found to be specific for the particular BP determinant. Thus, EAE may be mediated by lines of T lymphocytes reactive to different determinants on the BP molecule, but the resistance to EAE acquired by exposure to line cells is determinant specific. This suggests that acquired resistance to EAE is directed by the receptor specificity of the autoimmune anti-BP T cells.

Autoimmune encephalomyelitis (EAE) mediated or prevented by T lymphocyte lines directed against diverse antigenic determinants of myelin basic protein. Vaccination is determinant specific

Lines of T lymphocytes reactive against the basic protein of myelin (BP) were found in previous studies to mediate experimental autoimmune encephalomyelitis (EAE) in rats. Moreover, inoculation of rats with attenuated anti-BP line cells vaccinated them against subsequent attempts to induce active EAE by injection of BP in adjuvant. In the present study, we investigated the effects of T lymphocyte lines reactive to different antigenic determinants on the BP molecule, they are the major encephalitogenic peptide (EP) determinant present on guinea pig BP (G-BP), and minor, non-EP determinants present on bovine BP (B-BP). We found that both lines of T lymphocytes could mediate EAE. Resistance to active EAE acquired by spontaneous recovery from line mediated EAE or by vaccination with attenuated cells, however, was found to be specific for the particular BP determinant. Thus, EAE may be mediated by lines of T lymphocytes reactive to different determinants on the BP molecule, but the resistance to EAE acquired by exposure to line cells is determinant specific. This suggests that acquired resistance to EAE is directed by the receptor specificity of the autoimmune anti-BP T cells.