Intensive immunosuppression in the treatment of multiple sclerosis

Systemic immune derangements are shared across various CNS pathologies and reflect novel mechanisms of immune privilege

Background

The nervous and immune systems interact in a reciprocal manner, both under physiologic and pathologic conditions. Literature spanning various CNS pathologies including brain tumors, stroke, traumatic brain injury and de-myelinating diseases describes a number of associated systemic immunologic changes, particularly in the T-cell compartment. These immunologic changes include severe T-cell lymphopenia, lymphoid organ contraction, and T-cell sequestration within the bone marrow.

Methods

We performed an in-depth systematic review of the literature and discussed pathologies that involve brain insults and systemic immune derangements.

Conclusions

In this review, we propose that the same immunologic changes hereafter termed 'systemic immune derangements', are present across CNS pathologies and may represent a novel, systemic mechanism of immune privilege for the CNS. We further demonstrate that systemic immune derangements are transient when associated with isolated insults such as stroke and TBI but persist in the setting of chronic CNS insults such as brain tumors. Systemic immune derangements have vast implications for informed treatment modalities and outcomes of various neurologic pathologies.

Lymphangiography and Lymphatic Interventions

Compared with the traditional pedal lymphangiography, intranodal lymphangiography and MR lymphangiography have made imaging of the lymphatic system less challenging. Improvements in imaging and availability of newer catheters have allowed embolization of lymphatic system much more feasible that previously envisioned. In this article, we briefly review the anatomy, imaging, and current and future of lymphatic interventions.

Modern Techniques of Lymphangiography and Interventions: Current Status and Future Development

One of the crucial functions of the lymphatic system is maintenance of fluid balance. Nonetheless, due to lack of clinical imaging and interventional techniques, the lymphatic system has been under the radar of the medical community. The recently developed intranodal lymphangiography and dynamic contrast-enhanced MR lymphangiography provide new insight into lymphatic pathology. Thoracic duct embolization has become the method of choice for the treatment of patients with chylous leaks. Interstitial lymphatic embolization further expanded the lymphatic embolization approaches. Liver lymphatic lymphangiography and embolization allow treatment of postsurgical liver lymphorrhea and protein-losing enteropathy. The potential for further growth of lymphatic interventions is vast and includes liver lymphatic procedures and advanced thoracic duct interventions, such as thoracic duct externalization and stenting. These current and future advances will open up a realm of new treatments and diagnostic opportunities.

Indications, techniques, and clinical outcomes of thoracic duct interventions in patients: a forgotten literature?

BACKGROUND

The evolution of the "gut-lymph concept" has promoted thoracic duct (TD) lymph drainage as a possible treatment to reduce systemic inflammation and end-organ dysfunction in acute illness. The aim was to review the published experience of thoracic duct interventions (TDIs) aimed at improving clinical outcomes.

METHODS

A search of three databases (MEDLINE, EMBASE, and EMBASE CLASSIC) over the last 60 y. The indications for intervention, the technique, and clinical outcomes were reviewed.

RESULTS

There were a wide range of indications for TDI. These included reducing rejection after transplantation, treating inflammatory diseases, and reducing chronic failure of the liver, kidney, and heart. The techniques included TD cannulation and lymphovenuous fistula. The outcomes were variable and often equivocal, and this appears to reflect poor design quality. There is clinical equipoise regarding a therapeutic role of (TD lymph drainage in acute pancreatitis, and probably other acute diseases.

CONCLUSIONS

Until well-designed clinical trials are undertaken, the clinical benefits of TDIs will remain promising, but uncertain.

Epidemiology and infection in famine and disasters

Despite advances in health care in the tropics, and the inputs of international and voluntary organisations, famine and disaster continue to cause major devastation in many developing countries. In the aftermath of acute disasters such as earthquakes or cyclones and in chronic post-famine relief camps, mortality rates may be 20–30 times greater than those in ‘normal’ years [1]. The interaction of malnutrition, crowding, poor environmental sanitation, and changes in host parasite relationships due to migration or environmental change, result in communicable diseases playing a major role in excess morbidity and mortality.

Immunotherapy of multiple sclerosis

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.

Double-blind controlled trial of immunosuppression in the treatment of multiple sclerosis: final report

In a double-blind controlled trial 43 patients with relapsing-remitting multiple sclerosis were treated either with anti-lymphocyte globulin, prednisolone, and azathioprine, or with placebo preparations. Treatment began with a combination of the three medicaments but after 1 month was continued for another 14 months with azathioprine (3 mg/kg dialy) only. There was a marginally beneficial effect of immunosuppression on the overall relapse rate and clinical progression. However, there were significant effects on in-vitro lymphocyte function and in the visual evoked potentials in favour of the group receiving suppressive treatment. Placebo-treated patients of the HLA A3 tissue type had significantly more relapses than placebo-treated patients who were not of type HLA A3. Nevertheless, HLA-A3-positive patients treated with immunosuppression had significantly fewer relapses than A3-positive placebo-treated patients.

The significance of abnormal immune responses in patients with multiple sclerosis

Early diagnosis of multiple sclerosis (MS) may be assisted by tests for the abnormal immune responses of the central nervous system (CNS) including oligoclonal IgG bands in the cerebrospinal fluid (CSF), increased CNS IgG synthesis, increased CNS antibody synthesis against multiple viruses and increased numbers of enlarged lymphoid cells in the CSF. Alterations in immunological responses are important in the pathogenesis of MS. Further studies are needed, however, to identify the antigen(s) and/or antibodies responsible for oligoclonal IgG in the CSF of MS patients. Also, the cause(s) for the other immunological abnormalities with diagnostic importance need to be identified. The increased synthesis of antibodies against multiple unrelated viruses suggests generalized alteration in the immune regulatory system. The etiology of MS might be multifactorial involving abnormal immunological responses, possibly precipitated by infectious agents acquired during childhood by genetically susceptible individuals. The immunological responses including alterations in myelin basic protein concentration, antimyelin antibody and immune complex activities in CSF, and in vitro stimulation, suppression and migration inhibition of blood lymphocytes appear to correlate with stage of MS and severity of CNS damage. Some of the tests may become useful in estimating the prognosis of the disease. Longitudinal studies are needed to clarify the sensitivity of the diagnostic and prognostic immunological tests and etiological significance of these abnormalities in MS.

Double-blind, controlled trial of immunosuppression in treatment of multiple sclerosis

30 multiple sclerosis patients in a double-blind, controlled trial were given immunosuppressive treatment consisting of antilymphocyte globulin, prednisolone, and azathioprine, or placebo. After 15 months of treatment the immunosuppressed group had a reduction in the number of relapses and some retardation of the clinical course of the disease (p < 0.06). The beneficial effect was seen only in females.

Multiple sclerosis treated with antithymocyte globulin--a five year follow-up

Multiple sclerosis patients treated with antithymocyte globulin (ATG) were re-evaluated after five years. No long term benefit was found. Notably, the group of patients with an elevated gamma globulin to total protein ration in their C.S.F. and who did particularly well after treatment with ATG also failed to show any long term benefit. Few long term detrimental effects of ATG immunosuppression were identified. The implications of the results are discussed as they relate to the use of immunosuppression in multiple sclerosis.

Effect of a synthetic polypeptide (COP 1) on patients with multiple sclerosis and with acute disseminated encephalomeylitis. Preliminary report

Three patients with acute disseminated encephalomyelitis (ADE) and 4 patients in the terminal stages of multiple sclerosis (MS) were subjected to treatment with Cop 1, a synthetic copolymer of amino acids, which had previously been shown to have a beneficial effect in the treatment of experimental allergic encephalomyelitis (EAE). Under the treatment, the ADE patients recovered completely within 3 weeks, but 1 of 2 control cases treated with steroids showed complete recovery as well. The MS patients did not show any significant change in their motor function; however, 2 of them showed some improvement in vision and speech capacity. It is too early to conclude whether this improvement is related to the treatment. No side effect was observed in any of the patients treated with Cop. 1.

High incidence of horse serum protein allergy in various autoimmune disorders

In 186 persons (68 patients suffering from different so-called autoimmune diseases, 30 kidney recipients, 38 control patients from a surgical ward, and 50 healthy volunteers) the immune response to horse IgG was examined. The lowest rate of sensitization was found in kidney transplant recipients (3%) and the highest in autoimmune patients (33%). After excluding 39 patient who had received horse serum treatment prior to the examination, it was found that without previous injection of horse serum, 27% of the patients with autoimmune disease were sensitized to horse IgG. Compared to the other groups (kidney transplant recipients, 4%: surgical controls, 0%; healthy volunteers, 3%), this difference was statistically significant (p is less than 0.01).

Intensive immunosuppression with cyclophosphamide in multiple sclerosis. Follow up of 110 patients for 2-6 years

140 MS patients were treated with intensive I.V. cyclophosphamide immunotherapy and 110 were followed over 2-4 years. Annual relapse rate incidence was calculated over a period of 2 years before and after treatment and repeated neurological scores were made during this period. The conclusions are that 62% of the patients were stabilized during 2-4 years and that clinical improvement of the neurological signs was observed in most of the cases. It is concluded that intensive immunosuppression is able to interfere with the pathological processes involved in the pathogenesis of disseminated sclerosis.

Cumulation and elimination of horse-anti-dog lymphocyte and normal horse gammaglobulin in dogs

Two groups of dogs received daily intravenous doses of 20 mg/kg 131-I-labelled horse-anti-dog lymphocyte globulin or normal horse gammaglobulin respectively over a period of 11 days. Horse-anti-dog lymphocyte globulin showed a significantly higher eleimination rate than normal horse gammaglobulin. In contrary to the continuous increase in serum radioactivity during normal horse gammaglobulin treatment, there was a plateau after the 5th day in the horse-anti-dog lymphocyte globulin group. The xenogeneic protein concentration, measured with the single radial immunodiffusion technique, at the end of treatment was 165 +/- 8 mg/1 in the horse-anti-dog lymphocyte globulin, compared to 498 +/- 15 mg/1 in the normal horse gammaglobulin group. After treatment horse-anti-dog-lymphocyte globulin treated animals showed a significantly higher increase in active hemagglutination titer against horse erythrocytes with an average of 2(-8).

Clinical use of immunosuppressive drugs: part II

In haematological diseases, insufficient data has been accumulated to evaluate the efficacy of immunosuppressive drug treatment in patients with erythroid aplasia or sideroblastic anaemia. Cyclophosphamide may be efficacious in inhibiting circulating anticoagulants in patients who need continued replacement of clotting factors. Azathioprine, 6-mercaptopurine, cyclophosphamide and vincristine have been used successfully in treating patients with idiopathic thrombocytopenic purpura, and some patients with auto-immune haemolytic anaemia may benefit from the addition of purine analogues. However, the use of immunosuppressive therapy seems to accelerate the presence of haematological malignancies in patients with macroglobulinaemia. In gastro-intestinal diseases, uncontrolled studies have shown nitrogen mustard, 6-mercaptopurine and azathioprine to be of modest benefit to patients with ulcerative colitis and Crohn's disease. In a controlled trial azathioprine plus prednisone proved more effective than prednisone alone in sustaining remission in patients with Crohn's disease. In patients with either chronic active hepatitis or primary biliary cirrhosis, however, there seems to be no benefit from immunosuppressive therapy for primary treatment of these diseases. Cyclophosphamide, azathioprine and methotrexate have all been used with some success in treating patient with uveitis, and in a controlled trial cytarabine has been shown to be beneficial to patients with herpes ophthalmicus. However, no benefit has been shown to patients with the eye changes of Graves' disease with either azathioprine or methotrexate. Patients with Paget's disease appear to be helped by mithramycin. Cyclophosphamide, chlorambucil and azathioprine are ineffective in treating patients with multiple sclerosis. 6-Mercaptopurine, azathioprine, methotrexate and cyclophosphamide have all produced some benefit in patients with myasthenia gravis, and some patients with idiopathic pulmonary haemosiderosis have responded to azathioprine, 6-mercaptopurine and cyclophosphamide. Alkylating agents have proved useful in treating some patients with asthma and in treating frequent relapsers among children with the nephrotic syndrome. In adults with membrano-proliferative glomerulonephritis some patients have responded to combination therapy with cyclophosphamide, azathioprine and corticosteroids. Immunosuppressive therapy is also indicated in prolonging graft survivals in patients receiving organ transplants. Drug toxicities of immunosuppressive agents are discussed. Their long-term effects, including mutagenic potential, have as yet not been fully elucidated.

Treatment of the chronic progressive form of multiple sclerosis with a combination of cyclophosphamide and prednisone

32 patients with the chronic progressive form of the multiple sclerosis were treated with high doses of cyclophosphamide and prednisone during 20 days, to produce immunosuppression. The effect of treatment was measured by scoring three different Kurtzke scales just before treatment (1), just after treatment (II), and 3 months after treatment (III). The results indicate that in the treatment period I to II most patients improve, some dramatically. The improvement continues in 15 of 25 patients scored between 6 and 33 months after treatment. Better results were found in patients with shorter duration of their disease. More improvement is found as the IgG percentage of the spinal fluid at I is higher. The improvement is less when the initial condition (I) is more serious.