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Using murine monoclonal antibodies to mark total T cells, we have found rapid migration of T cells into the CSF in progressive multiple sclerosis patients, suggesting that the ongoing inflammatory responses in the CNS may depend on the continued movement of cells from the periphery into the target organ. Cloning experiments have indicated that the T cells present in the CSF during viral and post-viral encephalomyelitis represent sequestered populations of antigen-specific cells. In more chronic disease processes, these cells may also have restricted clonality as measured by the frequency of different T-cell receptor gene rearrangements on Southern blotting. It is known that there is restricted clonality of the B-cell immunoglobulin response in the CSF compartment with inflammatory CNS diseases, and with infections the majority of these so-called oligoclonal antibodies are directed against the exciting antigen and are synthesized in the CNS. Although we believe that T cells in the CNS originate from the blood, during the course of an inflammatory response the antigen and clonally-restricted populations found in the CSF may represent either selective migration or selective accumulation in the CNS. Selective migration might occur at the endothelial barrier as these cells can express Class II MHC antigens and act as antigen-presenting cells in the CNS (McCarron et al. 1985). Selective accumulation of T cells in the CNS might occur after non-specific migration of cells into the CNS followed by proliferation and expansion of T cells that have been induced by antigens in the brain. Antigen-presenting cells that are present in situ, such as astrocytes, may also play a role in the selective expansion of T cells in the CSF (Fontana et al. 1984). Alternatively, it is possible that T cells are induced to expand in the target CNS tissue non-specifically, e.g., via the CD2 pathway. In this regard, we have observed that CSF T cells exhibit alterations in stimulation by anti-T112 + anti-T113 monoclonal antibodies. The mechanism of damage to CNS tissue by immune cells is essentially unknown. For example there are no clear links between antibodies present in the CNS and CNS damage in SSPE where high titers of anti-measles antibodies are present. Whereas we did not observe high frequencies of measles-reactive cells in the CSF of a subject with SSPE, we did observe MHC non-restricted cytotoxic T cells which expressed TCR-gamma chains rather than alpha-beta chains.(ABSTRACT TRUNCATED AT 400 WORDS)

T-lymphocytes in the cerebrospinal fluid of patients with multiple sclerosis are predominantly CD4+ (inducer) as opposed to CD8+ (suppressor/cytotoxic) T cells. The CD4+ lymphocytes can be subdivided into populations that express high densities of the CDw29 (4B4) determinant and have helper inducer function or express high densities of CD45R (2H4) determinant and have suppressor inducer function. In the present study, we characterized the nature of these CD4+ T cells in the cerebrospinal fluid of patients with multiple sclerosis by performing flow cytometric analysis on paired samples of blood and cerebrospinal fluid. There were significantly lower percentages of CD4+2H4+ T cells in the cerebrospinal fluid than in the peripheral blood (p = 0.001, paired t test). In contrast, there were increased percentages of helper inducer (CD4+4B4+) T cells in the cerebrospinal fluid (p = 0.001, paired t test), compared with the peripheral blood. Analysis of subjects with other inflammatory disorders of the central nervous system did not show significant decreases in CD4+2H4+ T cells in cerebrospinal fluid, though in some, decreases were also observed. These results indicate that the CD4+ T cells in the cerebrospinal fluid of patients with multiple sclerosis are predominantly helper inducer, as opposed to suppressor inducer T cells, and that the relative decrease of suppressor inducer cells in the peripheral blood of multiple sclerosis patients is not due to their migration to the cerebrospinal fluid. Furthermore, the increased numbers of helper inducer cells in the cerebrospinal fluid may contribute to local autoimmune processes in the central nervous system compartment of multiple sclerosis patients.

Eight subjects inoculated orally with live attenuated poliovirus were investigated to study the effects of live virus infection on human T-cell responses. Proliferation to poliovirus and unrelated recall antigens were measured serially over a 3-week period. Five of eight subjects inoculated demonstrated a clear anamnestic response to poliovirus, but three did not. Only the five subjects demonstrating an anamnestic response to poliovirus were found to have augmented secondary immune responses to two unrelated recall antigens (tetanus toxoid and reovirus) and in the autologous mixed lymphocyte response (AMLR). No consistent changes were found in circulating T-cell surface activation antigens whether or not the subjects responded to poliovirus. These studies suggest that an asymptomatic poliovirus infection associated with immunization in humans can induce nonspecific secondary immune amplification as measured by in vitro T-cell proliferative response. This amplification pathway is a potential mechanism for immune responses against antigens other than those of the infecting virus.

Monoclonal antibodies have recently been characterized which identify activated T cells at different stages of differentiation. We compared the expression of the late appearing activation antigen defined by monoclonal antibody TS2/7 with the expression of early appearing activation antigens in a group of patients with active multiple sclerosis, encephalitis, non-inflammatory other neurologic diseases, and normal controls. An increase in TS2/7 reactivity of peripheral blood T cells was found in MS patients compared to controls (P less than 0.001), however, there was no increase in the level of early activation antigens. This was in contrast to three patients with viral encephalitis, who had an increase in the early activation antigen 4F2, but minimal, if any, increase in the TS2/7 reactive antigen. This study demonstrates that in vivo, as in vitro, it is possible to identify multiple differentiation stages for activated T cells. Furthermore, the presence of activated T cells in the peripheral blood of multiple sclerosis patients suggests that there is systemic immune activation in MS, and could provide a means to monitor abnormal immunologic activity in MS when these cells are functionally characterized.

We have studied the effects of various monoclonal antibody (MAb) infusions in patients with chronic progressive multiple sclerosis in the hope of developing an immunologically specific, nontoxic form of therapy for this disease. The immunologic responses to anti-T12, anti-T4, and anti-T11 MAb infusions were assessed in subjects with chronic progressive multiple sclerosis as part of phase I clinical studies. It was found that in vivo anti-T-cell MAb infusions specifically suppress in vitro measurements of the human immune response: anti-T11 MAb decreased T-cell activation by phytohemagglutinin, and anti-T4 MAb infusions abolished pokeweed mitogen-induced immunoglobulin synthesis without lysis of the CD4 + T-cell subpopulations. With repeated infusions of the anti-T11 MAb, anti-mouse antibodies were found in the circulation. Although most of the human anti-mouse antibody was not isotype-specific, significant anti-idiotypic activity was observed after repeated infusions in two of three subjects. The human anti-mouse antibodies were almost exclusively of the IgG isotype. The magnitude of the human anti-mouse response was significantly less after administration of either anti-T11 or anti-T4 as compared with anti-T12 MAbs. Murine anti-T-cell MAb can provide a specific, benign form of acute immunosuppression in humans. Repeated administration of these reagents in more chronic diseases can result in anti-idiotypic antibodies that block binding of the anti-T-cell MAbs to the T-cell surface. While the clinical usefulness of currently used murine MAbs in chronic diseases is restricted by the development of human anti-mouse antibodies, newer, more immunosuppressive MAbs may eliminate this problem.

Peripheral blood lymphocytes (PBL) from active and stable multiple sclerosis (MS) patients, patients with other neurologic diseases (OND), and control subjects were tested for sensitization to two myelin antigens not previously examined in multiple sclerosis, using a [3H]thymidine incorporation assay. The antigens investigated were myelin-associated glycoprotein (MAG) and proteolipid protein (PLP). In addition, sensitization to myelin basic protein (MBP) was also tested. Lymphocyte stimulation indices in active MS patients that were greater than 2 standard deviations above controls were as follows: 9/30 for MAG, 0/17 for PLP, and 8/81 for MBP. No control subjects responded to MAG or PLP, and only 1/29 control subjects responded to MBP. Three of the patients that responded to MAG also responded to MBP. Although the mean proliferative response to MAG and to MBP was greater in the population of active MS patients than in stable MS, ONDs, or controls, the difference was not statistically significant. The OND group was the only population which proliferated to PLP (6/16). The only statistically significant differences among the groups for all myelin antigens tested were the proportion of individuals with active MS vs. controls that responded to MAG (P less than 0.05), and OND vs. controls and active MS that responded to PLP (P less than 0.025). The greatest individual responses to the three antigens tested were to MBP in active MS patients. Elimination of the T8 (cytotoxic/suppressor) subset amplified the responses to myelin antigens in some patients and ONDs studied. These studies have demonstrated reactivity to MAG but not PLP in some patients with active MS, and reactivity to PLP in some patients with other neurologic diseases.

One hundred sixty-four patients with chronic progressive multiple sclerosis (MS) have been treated with a regimen of high-dose IV cyclophosphamide and ACTH over the past 6 years. Their status was reviewed to determine complications associated with treatment, dosage of medication used to induce a remission, factors which may predict a response to therapy, and subsequent course following treatment. One year following initial treatment, 81% of patients were improved or stabilized. Reprogression occurred in 69% of patients at a mean time of 17.6 months. Fifty-eight patients who initially stabilized after treatment and then reprogressed were treated a second time. One year after retreatment, 70% of these patients were improved or stabilized. Alopecia, nausea and vomiting, and minor infections were the most frequent complications. There were no deaths associated with treatment, the complication rate did not change with multiple treatments, and no late complications have yet been observed. Improvement tended to occur in younger patients with shorter disease duration. Although this treatment regimen is generally well tolerated and can favorably affect the course of chronic progressive MS in a majority of patients, a single treatment does not induce a permanent remission, and some form of maintenance treatment or retreatment is required. Current treatment programs involve testing a modified induction regimen and periodic outpatient booster injections to maintain remission.

Our work with multiple sclerosis has demonstrated a favorable effect on the course of chronic progressive multiple sclerosis in two-thirds of patients treated with cyclophosphamide/ACTH. However, alternative methods of therapy, or repeated treatments with cyclophosphamide and ACTH are required for longer term control of the illness. We are attempting to assess the efficacy of outpatient maintenance cyclophosphamide, but do not as yet have any data to support the use of this form of treatment. Cyclophosphamide and ACTH can be given to multiple sclerosis patients without significant serious toxicity. Monoclonal antibody therapy of multiple sclerosis is in its beginning stages. The treatment appears to be safe and has produced some interesting data indicating that rapid entry of some labeled lymphocytes into the nervous system can be measured by this technique. Since these are phase one pilot trials designed to assess immune parameters and only small numbers of patients have been treated, no clinical results have been obtained. No adverse effects of monoclonal antibody therapy were observed.

A single-cell cloning technique was used to analyze both phenotype and function of individual T cells in patients with multiple sclerosis (MS). Blood and cerebrospinal fluid (CSF) lymphocytes were plated at 1 cell per well, stimulated with phytohemagglutinin followed by interleukin 2, and expanded to 3 X 10(6) cells per "clone." More than 90% of the T8 clones generated from patients with MS and controls in both blood and CSF were cytotoxic precursors. There was also a slight decrease in cytotoxic T4 clones in the blood of patients with MS. The cytotoxic precursor frequencies of T cells in the CSF generally reflected those in the blood. In separate experiments, antigen reactivity was examined in lines established from blood or CSF. No reactivity to myelin basic protein or white matter was found in patients with MS or controls. Myelin basic protein-reactive clones could, however, be generated after first stimulating lymphocytes with antigen before cloning. These results suggest that changes in the T8 population from the blood of patients with MS involve cytotoxic as well as suppressor cells. Sequestration of myelin basic protein- or white matter-reactive T cells was not seen in the CSF of patients with MS, unlike reports of viral meningoencephalitis, in which large numbers of antigen-specific cells were found in the CSF. Direct single-cell clonal analysis of the CSF should provide a more sophisticated approach to the study of T cell abnormalities in patients with MS.

The frequency of virus-specific T cells in the cerebrospinal fluid of a patient with viral infection of the brain and meninges was determined by using a single-T-cell cloning technique where a representative sampling of T cells was cloned from the cerebrospinal fluid of a patient with varicella zoster viral (VZV) meningoencephalitis. That the derived T-cell clones were in fact clonal was shown by demonstrating, on Southern blot analyses, unique rearrangements of the T-cell antigen-receptor beta-chain genes of each clone. Five out of the 15 of the T4+ (CD4), 0/4 of the T8+ (CD8), and 0/1 of the T4+T8+ T-cell clones proliferated to VZV, while no clones proliferated to mumps virus or myelin basic protein. There was no clonal expansion of any VZV-reactive T cell in this patient's cerebrospinal fluid. As VZV meningoencephalitis is thought to be due to the reactivation of a dormant herpes zoster viral infection, it can be regarded as a secondary immune response. The presence of different T-cell receptor beta-chain gene rearrangements in each T-cell clone suggests that the T-cell response was polyclonal. These results demonstrate that a high frequency of polyclonal, T4+ antigen-specific T cells can be found in a naturally occurring, localized, immune response.

We have found an alteration in T-cell subsets in patients with active multiple sclerosis, specifically an increase in the T4:T8 ratio. These findings have been reproducibly obtained over the past four years, occurring in the majority of acute patients tested early in the course of an attack and in between 25 and 40% of chronic progressive patients, depending on their stage of illness. These changes correlate with pleocytosis in spinal fluid and with other abnormalities of immune function, such as spontaneous immunoglobulin production. They have been helpful in assessing disease activity in patients being treated on a variety of protocols and as part of research studies of immunoregulatory abnormality in multiple sclerosis, but have not been helpful as a diagnostic test for multiple sclerosis. The decrease of these cells in the peripheral blood of patients with active disease may be secondary to migration of these cells to the central nervous system, where they are sequestered.

The T4+ lymphocyte population includes a subset that induces suppressor T lymphocytes (T8+ cells) and can be distinguished by dual-color fluorescence analysis with anti-2H4 and anti-T4 monoclonal antibodies. To investigate the possible role of these cells in multiple sclerosis, we used anti-2H4 antibody to characterize peripheral-blood lymphocyte subsets in 63 patients with multiple sclerosis that was progressive, stable, or acute (relapsing-remitting). Twenty-three of 37 patients with progressive multiple sclerosis had a selective decrease in the number and percentage of peripheral-blood T cells that induce suppressor cells (T4+2H4+ cells), whereas only 3 of 16 patients with stable disease and 2 of 10 patients in the midst of an acute attack had a significant decrease. These selective decreases of circulating T4+2H4+ cells occurred in only 1 of 34 patient controls with other neurologic diseases and in 2 of 50 healthy controls (P less than 0.0001 by Fisher's exact test). The absolute number of T4+2H4+ cells and the percentage of reactivity in the populations studied were 187 +/- 28 per cubic millimeter and 8.3 +/- 1 percent in patients with progressive multiple sclerosis; 353 +/- 60 per cubic millimeter and 14.5 +/- 2 percent in patients with stable disease; 368 +/- 72 and 14.6 +/- 2.1 percent in patients with acute disease; 402 +/- 64 and 15.6 +/- 2 percent in controls with other neurologic diseases; and 519 +/- 44 and 19.7 +/- 1 percent in healthy controls. Functional studies using a pokeweed mitogen-driven IgG assay demonstrated a correlation between decreased numbers of T4+2H4+ cells and increased production of IgG in vitro. Family studies showed that the 2H4 antigen was not part of an inherited polymorphic antigenic determinant. Our results suggest that in progressive multiple sclerosis decreases in inducers of suppressor T cells may permit the activation of cells reactive with elements of the central nervous system.

Splenic lymphocytes from adult C57BL/6 mice infected with purified reovirus type 1 or 3 particles were fused with NS1 myeloma cells. Approximately 300 clones were obtained from each fusion (type 1 or type 3) and the supernatants from these clones were screened by radioimmunoassay for their ability to bind virus, T lymphocytes, brain, liver, lung tissues and isolated oligodendrocytes and ependymal cells. Approximately 10% of clones (33 and 26 clones, respectively) were positive for each fusion. For reovirus type 1:21% of positive clones bound only virus, 64% bound one of the normal tissues but not virus, and 15% bound both virus and one or more of the normal tissues. For reovirus type 3: 19% of positive clones bound only virus, 73% bound normal tissue only, and 8% bound both virus and normal tissue. Only 3 positive clones were obtained from uninfected control animals. These experiments demonstrate that (a) during the course of an immune response to a virus, autoantibodies are generated which react with a large variety of normal tissues and that (b) there are shared antigenic structures between viral determinants and normal tissue that can be identified by monoclonal antibodies. Although these results suggest two mechanisms by which an autoimmune response may develop following viral infection, the biological significance of these autoreactive monoclonal antibodies remains to be elucidated.

The autologous mixed lymphocyte reaction (AMLR) measures the T-cell response to antigens on the surface of autologous non-T-cells. Studies have shown a decreased ability of T-cells to proliferate during the AMLR in a number of autoimmune and viral disorders. The AMLR was studied in 56 patients with multiple sclerosis (MS), a presumed autoimmune disease of the central nervous system, and the response was correlated with T-cell subsets. The AMLR was decreased in active MS patients (3 117 +/- 573 cpm) as compared to inactive patients (5 896 +/- 1 800 cpm) (P less than 0.05) and normal controls (7 782 +/- 1 725 cpm) (P less than 0.01). There was no significant difference between inactive patients and normal controls (P greater than 0.1). A more pronounced difference was also seen when patients with active disease associated with peripheral blood T4/T8 ratios greater than 3.0 (1 045 +/- 223 cpm) were compared with normal controls (P less than 0.01). In addition, MS patients with T4/T8 ratios of less than 1.0 had an increased AMLR (9 256 +/- 1 762 cmp) as compared to patients with either a high T4/T8 ratio (P less than 0.001) or normal ratio (P less than 0.05). Thus, multiple sclerosis patients with clinically active disease have a decreased AMLR which correlates with high T4/T8 ratios in a subgroup of patients.

Immunoblot analysis was performed on the serum from 29 patients with polyneuropathy and monoclonal gammopathy. Nine patients had IgM spikes, and six of the nine had reactivity against myelin-associated glycoprotein (MAG) associated with a slowly progressive, predominantly sensory neuropathy. In contrast, 23 patients who lacked anti-MAG reactivity had more severe sensory motor neuropathy. Thus, IgM monoclonal gammopathy with reactivity against MAG may define a distinct clinical entity.

We found an increase in peripheral-blood lymphocytes bearing the T-cell-specific activation antigen Ta1 in 20 of 35 patients with progressive multiple sclerosis, 4 of 18 patients with stable or improving multiple sclerosis, 1 of 17 patients with other neurologic diseases, and 1 of 14 normal controls (P less than 0.0002, Fisher's exact test). No increases in two other markers of T-cell activation, T113 and the interleukin-2 receptor, were found. In the cerebrospinal fluid, patients with progressive multiple sclerosis (pleocytosis, 3.9 +/- 1.6 cells per cubic millimeter) had 42 +/- 3.0 per cent Ta1+ cells. In contrast, patients with other inflammatory central nervous system diseases (36 +/- 13 cells per cubic millimeter) had 9.6 +/- 1.8 per cent Ta1+ cells (P less than 0.01). In patients with other neurologic diseases without inflammation (0.7 +/- 0.16 cells per cubic millimeter), the percentage of Ta1+ cells was equivalent to that in patients with multiple sclerosis (39 +/- 5.4 per cent), although the absolute number was lower. There was a positive correlation between the presence of Ta1+ cells in the spinal fluid and blood of patients with other neurologic diseases, but not patients with multiple sclerosis. Less than 1 per cent of lymphocytes from the spinal fluid of patients with multiple sclerosis expressed interleukin-2 receptors, as compared with 9.8 per cent of cells from subjects with other inflammatory neurologic diseases (P less than 0.01). These results suggest that the T cells in the spinal fluid of patients with multiple sclerosis may be activated by a different mechanism or in a different temporal sequence from that in patients with other nervous system diseases. Furthermore, the increase in Ta1+ cells in the peripheral blood of patients with multiple sclerosis demonstrates systemic immune activation in the disease; monitoring such cells may provide an objective measure of abnormal immunologic activity.

Based on the assumption that multiple sclerosis is an autoimmune disease, a number of clinical trials designed to suppress the immune system or to restore immune balance in multiple sclerosis have been attempted. Depending on the disease category, the clinical goals of immunotherapy differ. Therapeutic goals include improving recovery from acute attacks, preventing or decreasing the number of relapses, and halting the disease in its progressive stage. The ultimate goal of multiple sclerosis therapy is the early treatment of patients in an attempt to halt the onset of progression. Specific strategies of immunotherapy include generation of a suppressor influence, removal of helper/inducer cells, manipulation of activated T cells, manipulation of class II major histocompatibility complex-bearing cells, alteration of lymphocyte traffic, extracorporeal removal of serum factors or cells, and manipulation of antigen-specific cells. Present treatment modalities are beginning to show some efficacy of nonspecific immunosuppression, but these treatments are limited by their toxicities. As the immunotherapy of multiple sclerosis moves to the next stage in the coming years, patients at an earlier stage of their disease will have to be treated, nontoxic forms of therapy developed, clinical trials lengthened, and a laboratory monitor of the disease developed. Given the positive effects of immunotherapy seen thus far in the disease, it is possible that appropriate immunotherapeutic intervention may provide effective treatment for the disease in the future.