The treatment of intractable rheumatoid arthritis with lymphoid irradiation

Deficits in T helper cells after total lymphoid irradiation (TLI): reduced IL-2 secretion and normal IL-2 receptor expression in the mixed leukocyte reaction (MLR)

Spleen cells from BALB/c mice treated with total lymphoid irradiation (TLI) and from normal, unirradiated mice were compared in the mixed leukocyte reaction (MLR). Although the percentage of CD4+ cells in the spleen was close to normal, 4 to 6 weeks after TLI, the MLR of unfractionated spleen cells from irradiated mice was more than 10-fold lower than controls. A similar reduction was observed when purified CD4+ cells were used as responders in the MLR. Secretion of IL-2 by cells from irradiated mice was also about 10-fold lower than controls. However, the percentage of CD4+ and CD8+ cells which expressed IL-2 surface receptors during the MLR was similar using spleen cells from irradiated and control mice. Addition of an exogenous source of IL-2 restored the proliferative capacity of the irradiated cells and suggests that the lack of IL-2 secretion is the likely explanation of the marked deficit in the MLR of CD4+ spleen cells after TLI.

Treatment of experimental myasthenia gravis with total lymphoid irradiation

Total lymphoid irradiation (TLI) has been reported to be effective in the immunosuppressive treatment of certain human and experimental autoimmune disorders. We have investigated the effects of TLI in Lewis rats with experimental autoimmune myasthenia gravis (EAMG) produced by immunization with purified torpedo acetylcholine receptor (AChR). The radiation is given in 17 divided fractions of 200 rad each, and nonlymphoid tissues are protected by lead shielding. This technique suppresses the immune system, while minimizing side effects, and permits the repopulation of the immune system by the patient's own bone marrow cells. Our results show that TLI treatment completely prevented the primary antibody response to immunization with torpedo AChR, it rapidly abolished the ongoing antibody response in established EAMG, and it suppressed the secondary (anamnestic) response to a boost of AChR. No EAMG animals died during TLI treatment, compared with six control animals that died of EAMG. TLI produces powerful and prompt immunosuppression and may eventually prove useful in the treatment of refractory human myasthenia gravis.

Total lymphoid irradiation in patients with refractory rheumatoid arthritis

Eleven patients with rheumatoid arthritis that had been refractory to conventional drug therapy were treated with total lymphoid irradiation (TLI). Followup continued for 6 months in 9 patients, 12 months in 6 patients, and 24 months in 3 patients. At 6 and 12 months post-TLI, a significant improvement in clinical disease activity was demonstrated. Side effects noted during TLI included fatigue, nausea, diarrhea, and vomiting. One patient died of cardiorespiratory arrest, 2 patients died of kidney failure secondary to generalized amyloidosis, and 1 patient died of septic shock secondary to a multilocular septic arthritis. One patient experienced 2 episodes of septic arthritis; 2 patients manifested delayed wound healing. Immunologic assessments showed consistent lymphopenia in all patients. T lymphocyte subsets decreased after TLI, and showed a transient increase at 6 months post-TLI. The suppressed mitogen responsiveness, which was noted 2 months after irradiation, was found to increase almost to the pre-TLI levels at 12 months. The observed increase in morbidity and mortality after TLI is evidence that discourages the use of this therapeutic technique, at least in its present form.

Radiation oncology. Programs for the present and future

Radiation oncology in 1984 continues to make major advances in the multidisciplinary clinical programs. This has been possible by virtue of the radiation oncologist, who is an active participant in these clinical programs. The changing role for the radiation oncologist has dictated a greater participation in the primary management of the patient's disease process and also participation in multidisciplinary research programs.

Total lymphoid irradiation as an immunosuppressive agent for transplantation and the treatment of 'autoimmune' disease: a review

Total lymphoid irradiation (TLI) is a powerful immunosuppressive agent. This immunosuppression has the potential for clinical application in certain selected situations. In this review, the immunological changes produced by TLI and its potential applications in organ transplantation and the treatment of certain 'autoimmune' diseases are discussed.

Treatment of intractable rheumatoid arthritis with total lymphoid irradiation (TLI): immunological and clinical changes

Eleven patients with intractable rheumatoid arthritis were treated with total lymphoid irradiation in a feasibility study. The mantle and the inverted Y fields were treated successively to a cumulative dose of 2000 rads. Nine of eleven patients showed at least a 35% improvement in three of four clinical parameters by six months and continued to maintain at least this level of improvement at their last observation points (13-28 months after TLI). There was a marked decrease in the percentage of total T cells and Leu-3 cells (helper), but an increase in the percentage of Leu-2 cells (suppressor/cytotoxic), resulting in a dramatic increase in the Leu-2/Leu-3 ratio. There was also a decrease in response to PHA, Con A and MLR.

The effects of conventionally fractionated, extended portal radiotherapy on the human peripheral blood count

Conventionally fractionated, extended portal radiotherapy (CFEPRT) has been used to treat two diseases in which there was no marrow infiltration (viz. Hodgkin's disease and medulloblastoma). Blood count indices have been monitored during therapy and in the recovery phase. The lymphocytes were the most sensitive and the monocytes the most refractory leucocytes to change; the monocyte count tended to recover during CFEPRT. The platelet count fell gradually and soon after the neutrophil count. The nadir counts for white cells and platelets occurred early or toward the middle of CFEPRT, after which levels were maintained. The hemoglobin slightly and progressively declined. The patterns of change were similar for the two portals analyzed. Absolute eosinophilia occurred in 9 of the 53 CFEPRT patients, often in the recovery period. All patients who maintained their early nadir levels throughout the rest of the CFEPRT demonstrated fast recovery of all indices following completion of radiotherapy; the lymphocyte count recovered fastest. Recent prior CFEPRT or standard MVPP (nitrogen mustard, vinblastine, procarbazine, prednisolone) chemotherapy rendered the blood count more liable to radiation induced cytopenia. A lapse of more than 3 months between MVPP and CFEPRT allowed greater tolerance to the radiotherapy. Recent MVPP may be less myelosuppressive than recent mantle radiotherapy with respect to subsequent tolerance to CFEPRT.

Successful treatment of autoimmune manifestations in MRL/l and MRL/n mice using total lymphoid irradiation (TLI)

The autoimmune manifestations of MRL-+/+ (MRL/n) and MRL/Mp-lpr/lpr (MRL/l) murine models of systemic lupus erythematosus (SLE) were successfully reversed following total lymphoid irradiation (TLI) therapy consisting of 8-12 daily fractions of 200 rad. Following radiotherapy the characteristic lymphadenopathy of MRL/l disappeared, proteinuria was 334 mg% compared to a peak of 2272 mg% in untreated controls, and the median survival time was prolonged to 423 days compared to 214 days in untreated mice. The albuminuria of TLI-treated MRL/n mice was 194 mg% compared to 1180 mg% in untreated controls. The survival of treated MRL/n mice was prolonged to a median of 389 as compared to 190 days in untreated controls. The effect of TLI on antiDNA antibodies in both MRL/l and MRL/n was less remarkable. However, the antiDNA activity reached normal levels in most long-living mice. The most impressive finding was complete reversal and/or prevention of the SLE-like glomerulonephritis in MRL/l mice as documented by light and electron microscopy. Immunomanipulation with TLI should be further evaluated as a possible treatment modality in intractable human autoimmune disorders.

Treatment of intractable rheumatoid arthritis with total lymphoid irradiation

Eleven patients with intractable rheumatoid arthritis were treated with total lymphoid irradiation (total dose, 2000 rad) in an uncontrolled feasibility study, as an alternative to long-term therapy with cytotoxic drugs such as cyclophosphamide and azathioprine. During a follow-up period of five to 18 months after total lymphoid irradiation, there was a profound and sustained suppression of the absolute lymphocyte count and in vitro lymphocyte function, as well as an increase in the ratio of Leu-2 (suppressor/cytotoxic) to Leu-3 (helper) T cells in the blood. Persistent circulating suppressor cells of the mixed leukocyte response and of pokeweek mitogen-induced immunoglobulin secretion developed in most patients. In nine of the 11 patients, these changes in immune status were associated with relief of joint tenderness and swelling and with improvement in function scores. Maximum improvement occurred approximately six months after irradiation and continued for the remainder of the observation period. Few severe or chronic side effects were associated with the radiotherapy.

Clinical and immunologic effects of fractionated total lymphoid irradiation in refractory rheumatoid arthritis

Ten patients with refractory rheumatoid arthritis were given 3000 rad of fractionated total lymphoid irradiation in an uncontrolled therapeutic trial. Total lymphoid irradiation was associated with objective evidence of considerable clinical improvement in eight patients and with reduced blood lymphocyte counts in all 10. On completion of irradiation, there was an abrogation of lymphocyte reactivity in vitro in the patients with clinical responses, but abnormal antibody activities characteristic of rheumatoid arthritis and normal components of humoral immunity were not suppressed. Partial recrudescence of arthritis occurred shortly after a year after the completion of irradiation and was paralleled by a restitution of lymphocyte concentrations and responsiveness to mitogens to levels similar to those observed before irradiation. These data provide further evidence of T-cell involvement in the pathogenesis of rheumatoid arthritis and demonstrate that total lymphoid irradiation can induce temporary relief, but they do not ascertain whether the natural history of this disease was altered.

'Managing' the immune system with total lymphoid irradiation

Total lymphoid irradiation (TLI), which in the past was limited to the treatment of malignant disease, is now emerging as a practical technique in the management of unwanted immune reactions in the areas of transplant tolerance and various autoimmune diseases. Current studies are particularly promising for application of TLI in rheumatoid arthritis and lupus nephritis.