Tumor-specific cytolysis by lymphocytes infiltrating human melanomas

Tumor infiltrating lymphocytes (TIL) were grown in IL-2 from single cell tumor suspensions of 14 human melanomas resected from 12 patients. As a function of time in culture, 4 of 14 TIL cultures eventually expressed highly specific cytolytic activity against fresh autologous melanoma targets in short term chromium release assays, failing to lyse multiple allogeneic tumors or autologous normal cells. These highly specific TIL were identified as CTL by phenotype (CD3+/CD4-/CD8+/Leu7-) and by function (lysis inhibited by antibodies directed against CD3 and MHC class I molecules). Cell separation experiments using immunomagnetic beads identified a highly tumor-specific CTL subpopulation within a nonspecific TIL culture, suggesting that the lytic activity of tumor-specific CTL may be diluted by the nonspecific killer activity present in heterogeneous TIL cultures. These studies provide evidence for specific MHC-restricted human immune responses against autologous tumor in cancer-bearing patients, and may be of importance to ongoing clinical trials using TIL in the immunotherapy of advanced malignancies.

Metastasectomy for soft tissue sarcoma. Further evidence for efficacy and prognostic indicators

Between 1982 and 1987, 74 patients (46 men and 28 women) had exploration for presumed metastases from high-grade soft tissue sarcoma of the head/neck, extremity, or trunk. Ages ranged from 11 to 75 years (median 38 years). Thirty (41%) had multiple procedures for recurrences (range two to six explorations). Median postthoracotomy time for the group of patients with histologically confirmed sarcoma (n = 63) was 20.3 months. Patients rendered free of disease at initial thoracotomy had significantly longer postthoracotomy survival times (26.8 months median) than those with unresectable metastatic disease (9 months median); p2 less than 0.0001). The prognostic significance of age, sex, location of primary tumor, disease-free interval, number of nodules on preoperative computed tomograms or conventional linear tomograms, number of metastases resected, and the use of postoperative chemotherapy were analyzed. In a univariate analysis, sex, age, and location of the primary tumor did not impact significantly on survival, nor did the use of postoperative chemotherapy. Initial disease-free interval of 1 year or less was associated with a significantly shorter survival time, and patients with five nodules or fewer on preoperative computed tomography had significantly longer survival times than patients with six nodules or more. Patients with three nodules or fewer on linear tomography had a longer postthoracotomy survival time than patients with four nodules or more. In patients whose malignant disease could be completely resected, the number of nodules resected at thoracotomy did not impact on long-term survival. According to proportional-hazards modeling, disease-free interval, sex, resectability, and truncal location were found to associate with length of survival after metastasis removal. We conclude that pulmonary metastasis resection in patients with soft tissue sarcoma is associated with long-term survival, and consistent indicators can define which patients may benefit from these interventions.

The effect of various cytokines on the in vitro induction of antibody-dependent cellular cytotoxicity in murine cells. Enhancement of IL-2-induced antibody-dependent cellular cytotoxicity activity by IL-1 and tumor necrosis factor-alpha

We have previously demonstrated that incubation with IL-2 can induce ADCC activity in murine cells and that this activity was mediated by asialo GM1+, FcR+ cells. In the present study we show that the cytokines IFN-alpha and IFN-gamma, TNF-alpha, and IL-1 alpha are unable to induce antibody-dependent cellular cytotoxicity (ADCC) in murine cells; however, TNF-alpha and IL-1 alpha could substantially augment the ADCC induced by IL-2. IL-1 increased the IL-2-induced ADCC activity in a dose-dependent fashion and in cells isolated from the thymus and spleen. The precursors of the ADCC induced by the combination of IL-1 and IL-2 were asialo GM1+ cells, similar to the precursor cells of IL-2-induced ADCC. The effect of IL-1 and TNF on ADCC was not the result of an increase in the FcR density on the cell surface or the result of an increase in the number of FcR+ cells although IL-1 increased the recovery of viable cells in culture. The main effect of IL-1 and TNF was the enhancement of the lytic ability of the IL-2 cultured cells as indicated by increased intra-cellular benzyloxycarbonyl L-lysine thiobenzylester-esterase activity. These results suggest that lymphokines such as IL-1 and TNF may synergize with IL-2 in the induction of ADCC and could thus potentially be useful for the immunotherapy of established tumors when combined with the administration of specific anti-tumor antibodies.

The effect of various cytokines on the in vitro induction of antibody-dependent cellular cytotoxicity in murine cells. Enhancement of IL-2-induced antibody-dependent cellular cytotoxicity activity by IL-1 and tumor necrosis factor-alpha

We have previously demonstrated that incubation with IL-2 can induce ADCC activity in murine cells and that this activity was mediated by asialo GM1+, FcR+ cells. In the present study we show that the cytokines IFN-alpha and IFN-gamma, TNF-alpha, and IL-1 alpha are unable to induce antibody-dependent cellular cytotoxicity (ADCC) in murine cells; however, TNF-alpha and IL-1 alpha could substantially augment the ADCC induced by IL-2. IL-1 increased the IL-2-induced ADCC activity in a dose-dependent fashion and in cells isolated from the thymus and spleen. The precursors of the ADCC induced by the combination of IL-1 and IL-2 were asialo GM1+ cells, similar to the precursor cells of IL-2-induced ADCC. The effect of IL-1 and TNF on ADCC was not the result of an increase in the FcR density on the cell surface or the result of an increase in the number of FcR+ cells although IL-1 increased the recovery of viable cells in culture. The main effect of IL-1 and TNF was the enhancement of the lytic ability of the IL-2 cultured cells as indicated by increased intra-cellular benzyloxycarbonyl L-lysine thiobenzylester-esterase activity. These results suggest that lymphokines such as IL-1 and TNF may synergize with IL-2 in the induction of ADCC and could thus potentially be useful for the immunotherapy of established tumors when combined with the administration of specific anti-tumor antibodies.

Combination cytokine immunotherapy with tumor necrosis factor alpha, interleukin 2, and alpha-interferon and its synergistic antitumor effects in mice

The antitumor activity of combination therapy with recombinant human tumor necrosis factor alpha (rhTNF-alpha), recombinant human interleukin 2 (rhIL-2), and recombinant hybrid alpha-interferon A/D (rhIFN-alpha A/D) was assessed against established weakly immunogenic (MCA-106) and nonimmunogenic (MCA-102) sarcomas at both s.c. and visceral (hepatic) sites. C57BL/6 mice were treated with a single i.v. dose of rhTNF-alpha followed by rhIL-2 (75,000 units) and rhIFN-alpha A/D (75,000 units) i.p. twice daily for 5 consecutive days. Substantial improvements were observed when the combination of rhTNF-alpha, rhIL-2, and rhIFN-alpha A/D was administered, as measured by regression of tumor, prolongation of survival, and improved cure rates, compared with any combination of two cytokines or any cytokine alone against the MCA-106 sarcoma. These findings were consistent in both the s.c. and single hepatic tumor models. For example, treatment of the MCA-106 s.c. tumor bearers with the triple cytokine combination resulted in cures of 16 of 18, 17 of 18, and 12 of 18 mice receiving rhTNF-alpha dosages of 2, 4, and 6 micrograms, respectively, compared with 2 of 18, 7 of 18, and 9 of 18 at 2, 4, and 6 micrograms of rhTNF-alpha plus rhIL-2 without rhIFN-alpha A/D. Established 10-day single liver tumor weights when treated with the triple combination therapy were 54 and 25 mg in treatment groups receiving 2 and 4 micrograms of rhTNF-alpha, compared with 376 and 302 mg with the same amounts of rhTNF-alpha alone (P less than 0.004). Mice bearing hepatic sarcomas treated with triple cytokine combination therapy had cure rates of 50% and 67% at rhTNF-alpha doses of 2 and 4 micrograms, compared with no survivors with rhTNF-alpha alone. No improved antitumor effects resulted from therapy with any cytokine alone or in combination against the nonimmunogenic MCA-102 sarcoma. Possible in vivo mechanisms by which these three cytokines synergize are discussed.

Cytokines alter target cell susceptibility to lysis. II. Evaluation of tumor infiltrating lymphocytes

We studied the susceptibility of autologous and allogeneic tumors to lysis by human tumor infiltrating lymphocytes (TIL) after pre-incubation of the tumors with human rIFN-gamma and human rTNF-alpha. Preincubation of the tumor lines with IFN-gamma or TNF enhanced susceptibility to lysis significantly; the combination of both cytokines was more effective than either alone. Pretreatment for at least 24 h was required to enhance lytic susceptibility and maximal lysis was observed after pretreatment for 48 to 72 h. Highly specific TIL lysed only their autologous tumor targets and failed to lyse cytokine pretreated allogeneic tumor cells. In TIL populations with varying specificity, cytokine pretreatment of targets enhanced autologous lysis as well as allogeneic lysis. This cytokine-mediated effect could also be observed in a lectin-dependent cytotoxicity assay and did not correlate directly with enhanced expression of MHC class I Ag or the adhesion molecules LFA-3 and ICAM-1. These results suggest that enhancement of lysis may occur at a postbinding stage by making the target cell more sensitive to the cytotoxic factors delivered by the killer cell. The fact that lysis of cytokine treated targets by cells with LAK activity was not enhanced suggests that cells with lymphokine-activated killer activity and tumor-derived T cells kill tumor targets via different mechanisms.

Renal toxicity of interleukin-2 administration in patients with metastatic renal cell cancer: effect of pre-therapy nephrectomy

Systemic administration of interleukin-2 and lymphokine-activated killer cells is a new approach to the immunotherapy of advanced cancer. Metastatic renal cell cancer is one of the histological types of tumors particularly susceptible to this treatment approach although renal toxicity often is a dose-limiting side effect. We compared the renal functional changes observed during interleukin-2 therapy in 52 consecutive patients with advanced renal cancer to that of 83 consecutive patients with metastatic nonrenal cancer. Of the 52 patients with renal cancer 41 had recently undergone nephrectomy. The over-all peak serum creatinine values and the percentage increase of serum creatinine over baseline for all patients studied were significantly higher in cycle 2 of interleukin-2 therapy than in cycle 1: 3.8 +/- 0.2 versus 2.6 +/- 0.1 mg. per dl. and 241.7 +/- 16.5 versus 140.3 +/- 11.0 per cent, respectively. In patients with pre-therapy serum creatinine values of 0.4 to 0.9 mg. per dl. there were no significant differences in the mean peak serum creatinine nor in the percentage increase over baseline between renal and nonrenal cancer patients during cycle 1. In cycle 2 of therapy these values were higher in the renal cancer group (3.6 +/- 0.8 versus 2.4 +/- 0.2 mg. per dl. and 310.4 +/- 103.5 versus 214 +/- 30.4 per cent, respectively) but they did not reach statistical significance (P2 = 0.08 and 0.25, respectively). Renal and nonrenal cancer patients with pre-therapy serum creatinine levels of 1.0 to 1.4 mg. per dl. achieved similar high values in cycle 2 of interleukin-2 therapy (3.9 +/- 0.3 versus 3.9 +/- 0.4 mg. per dl. and 222.7 +/- 23.2 versus 248.7 +/- 33.5 per cent, respectively), although the initial increase (cycle 1) was higher in the renal cancer patients (3.3 +/- 0.3 versus 2.4 +/- 0.2 mg. per dl. and 172.3 +/- 25.9 versus 116.1 +/- 18.0 per cent, respectively). Baseline serum creatinine greater than or equal to 1.5 mg. per dl. was associated with an over-all higher peak serum creatinine and higher percentage increase of serum creatinine over baseline than that below 1.5 mg. per dl. baseline: 4.4 mg.per dl. and 171.1 +/- 36.3 per cent in cycle 1 and 6.5 +/- 0.7 mg. per dl. and 296.1 +/- 44.0 per cent in cycle 2, respectively (p less than 0.01). There was no association between peak serum creatinine and interval from nephrectomy to interleukin-2 therapy.(ABSTRACT TRUNCATED AT 400 WORDS)

IL-6/IFN-beta-2 as a circulating hormone. Induction by cytokine administration in humans

IL-6/IFN-beta 2 is a family of phosphoglycoproteins ranging in size from 19 to 30 kDa which elicits a broad range of physiologic and immune responses. Several cytokines, including TNF, have been shown to stimulate IL-6 production in cell culture. In this report, we describe the rapid induction of circulating biologically active IL-6 by the systemic administration of rTNF to patients with cancer. Low levels of IL-6 activity could be detected in the sera of patients as early as 5 min after rTNF infusion. IL-6 levels peaked approximately 2 to 3 h after rTNF bolus administration and were undetectable in most cases within 8 h. IL-6 was detected in two separate bioassays--the hybridoma B9 proliferation and the hepatocyte-stimulating factor assay. Maximum detectable levels of IL-6 ranged from 160 to 310 hybridoma growth factor units and 11-82 ng/ml in the hepatocyte-stimulating factor assay. IL-6 induction decreased after serial, daily doses of rTNF. Serial serum samples of patients receiving IL-2 or IFN-alpha were also assayed for IL-6 production. IL-2-treated but not IFN-alpha-treated patients generated low levels of IL-6 (range less than 20 to 95 hybridoma growth factor units/ml). Interestingly, in patients treated with IL-2, serum levels of TNF were detectable and peak TNF activity preceded measurable IL-6 levels. Serum levels of acute phase plasma proteins and of corticosteroid rose in response to rTNF administration. C-reactive protein increased (2.5 to 4.0-fold) within 8 h of rTNF administration and cortisol levels rose (10- to 20-fold) within 4 h after rTNF injection. We conclude that rTNF administration in man leads to the induction of circulating IL-6 which, due to its broad range of activities, may be an important physiologic signal regulating the immune response.

IL-6/IFN-beta-2 as a circulating hormone. Induction by cytokine administration in humans

IL-6/IFN-beta 2 is a family of phosphoglycoproteins ranging in size from 19 to 30 kDa which elicits a broad range of physiologic and immune responses. Several cytokines, including TNF, have been shown to stimulate IL-6 production in cell culture. In this report, we describe the rapid induction of circulating biologically active IL-6 by the systemic administration of rTNF to patients with cancer. Low levels of IL-6 activity could be detected in the sera of patients as early as 5 min after rTNF infusion. IL-6 levels peaked approximately 2 to 3 h after rTNF bolus administration and were undetectable in most cases within 8 h. IL-6 was detected in two separate bioassays--the hybridoma B9 proliferation and the hepatocyte-stimulating factor assay. Maximum detectable levels of IL-6 ranged from 160 to 310 hybridoma growth factor units and 11-82 ng/ml in the hepatocyte-stimulating factor assay. IL-6 induction decreased after serial, daily doses of rTNF. Serial serum samples of patients receiving IL-2 or IFN-alpha were also assayed for IL-6 production. IL-2-treated but not IFN-alpha-treated patients generated low levels of IL-6 (range less than 20 to 95 hybridoma growth factor units/ml). Interestingly, in patients treated with IL-2, serum levels of TNF were detectable and peak TNF activity preceded measurable IL-6 levels. Serum levels of acute phase plasma proteins and of corticosteroid rose in response to rTNF administration. C-reactive protein increased (2.5 to 4.0-fold) within 8 h of rTNF administration and cortisol levels rose (10- to 20-fold) within 4 h after rTNF injection. We conclude that rTNF administration in man leads to the induction of circulating IL-6 which, due to its broad range of activities, may be an important physiologic signal regulating the immune response.

Cytokines alter target cell susceptibility to lysis. II. Evaluation of tumor infiltrating lymphocytes

We studied the susceptibility of autologous and allogeneic tumors to lysis by human tumor infiltrating lymphocytes (TIL) after pre-incubation of the tumors with human rIFN-gamma and human rTNF-alpha. Preincubation of the tumor lines with IFN-gamma or TNF enhanced susceptibility to lysis significantly; the combination of both cytokines was more effective than either alone. Pretreatment for at least 24 h was required to enhance lytic susceptibility and maximal lysis was observed after pretreatment for 48 to 72 h. Highly specific TIL lysed only their autologous tumor targets and failed to lyse cytokine pretreated allogeneic tumor cells. In TIL populations with varying specificity, cytokine pretreatment of targets enhanced autologous lysis as well as allogeneic lysis. This cytokine-mediated effect could also be observed in a lectin-dependent cytotoxicity assay and did not correlate directly with enhanced expression of MHC class I Ag or the adhesion molecules LFA-3 and ICAM-1. These results suggest that enhancement of lysis may occur at a postbinding stage by making the target cell more sensitive to the cytotoxic factors delivered by the killer cell. The fact that lysis of cytokine treated targets by cells with LAK activity was not enhanced suggests that cells with lymphokine-activated killer activity and tumor-derived T cells kill tumor targets via different mechanisms.

Decrease in interleukin 2-induced vascular leakage in the lungs of mice by administration of recombinant interleukin 1 alpha in vivo

The administration of interleukin 2 (IL-2) to mice and humans is limited by the induction of a dose-dependent increase in vascular permeability causing a vascular leak syndrome (VLS). We have investigated the impact of the injection of recombinant interleukin 1 alpha (IL-1 alpha) on the VLS induced by IL-2 by measuring the extravasation of 125I-albumin into tissues and by assessing wet and dry lung weights. IL-1 alpha alone did not induce any significant extravasation of radiolabeled albumin. IL-2 alone, however, caused a significant increase in the extravasation compared to control lungs. IL-1 alpha injection along with IL-2 significantly reduced the IL-2-induced extravasation of radiolabeled albumin [9,886 +/- 533 (SEM) cpm were observed in IL-2 and IL-1 alpha-treated lungs compared to 14,172 +/- 2,628 cpm in lungs treated with IL-2 alone (P less than 0.02)]. IFN-alpha in combination with IL-2 produced more severe vascular leakage than caused by IL-2 alone. IL-1 alpha also significantly decreased (P less than 0.05) the vascular permeability induced by the combination of IFN-alpha and IL-2. We observed 44,811 +/- 13,131 cpm in IFN-alpha- and IL-2-treated lungs compared to 18,350 +/- 2,622 cpm in IFN-alpha-, IL-2-, and IL-1 alpha-treated lungs. The IL-2- and IFN-alpha-induced increase in lung water weight was also reduced significantly by the addition of IL-1 alpha. The decrease in vascular leakage was dependent on the dose and timing of IL-1 alpha administered. When recombinant IL-1 alpha was given as a single i.p. injection, 24 h before the injection of IL-2 (or Hanks' balanced salt solution) or IL-2 and IFN-alpha no abrogation of the VLS was observed. Although IL-1 alpha decreased VLS significantly in mice treated with IFN-alpha and IL-2 the survival of mice was not improved by the simultaneous administration of IL-1 alpha. Histologically, treatment with IFN-alpha and IL-2 produced marked perivascular and intraalveolar edema which was completely eliminated by the addition of IL-1 alpha. However, some perivascular edema in IL-1 alpha-treated mice remained which was equivalent to that caused by IL-2 alone. Treatment of MCA-106 induced pulmonary metastases was enhanced by the administration of IFN-alpha and IL-2 together.(ABSTRACT TRUNCATED AT 400 WORDS)

Hodgkin's disease: challenges for the future

Clinical investigators of Hodgkin's disease of the recent past have reason to be proud. Tens of thousands of individuals, many of them young, fertile, and productive, have been cured of their life-threatening disease. There are few better examples of the success and rewards of clinical oncology than in the control of Hodgkin's disease by improved diagnostic methods and the appropriate use of radiation and chemotherapy. Yet the clinical investigator of today cannot be satisfied with these successes. The treatment required for high cure rates remains empirical, difficult, and costly. The goal must be to prevent or reverse this fascinating disease, utilizing specific therapy designed from a knowledge of the cause and pathogenesis of the disease. There are sufficient biological clues and methodologies to predict that this will be possible, and in the decade of the 1990s!

Tumor localization of adoptively transferred indium-111 labeled tumor infiltrating lymphocytes in patients with metastatic melanoma

Lymphoid cells infiltrating into human tumors can be expanded in vitro in medium containing interleukin-2 (IL-2). Adoptive transfer of these tumor-infiltrating lymphocytes (TIL) mediates potent antitumor effects in murine tumor models. Clinical trials to evaluate the efficacy of these cells in patients with advanced cancer are underway. We have investigated whether infused TIL labeled with indium 111 (111In) oxine can traffic and localize to metastatic deposits of tumor. Six patients with metastatic malignant melanoma who had multiple sites of subcutaneous, nodal, and/or visceral disease were the subjects of the study. The patients received cyclophosphamide 36 hours before receiving the intravenous (IV) infusion of TIL followed by IL-2 IV every eight hours. The distribution and localization of the TIL were evaluated using serial whole body gamma camera imaging, serial blood and urine samplings, and serial biopsies of tumor and normal tissue. 111In-labeled TIL localized to lung, liver, and spleen within two hours after the infusion of activity. Activity in the lung diminished within 24 hours. As early as 24 hours after injection of 111In-labeled TIL, localization of TIL to sites of metastatic deposits was demonstrated in all six patients using either imaging studies or biopsy specimens or both. 111In activity in tumor tissue biopsies ranged from three to 40 times greater than activity in normal tissue. A progressive increase in the radioactive counts at sites of tumor deposit was seen. This study shows that labeled TIL can localize preferentially to tumor, and provides information concerning the possible mechanism of the therapeutic effects of TIL.

Intratumoral LAK cell and interleukin-2 therapy of human gliomas

Adoptive immunotherapy using lymphokine-activated killer (LAK) cells and interleukin-2 (IL-2) offers the possibility of a new treatment for patients with malignant glial tumors. In a clinical trial, the effectiveness of a 5-day treatment cycle of direct intratumoral administration of both LAK cells and IL-2 via a reservoir/catheter system in patients with recurrent malignant gliomas was studied. Ten patients were entered into the study, nine of whom were treated with 15 cycles of LAK cells (0.9 to 21.0 x 10(9) cells) and IL-2 (49 to 450 x 10(3) U/kg). The 10th patient in the study was not treated because of the onset of severe neurological deficits prior to beginning immunotherapy. Of the nine patients treated, one had a partial tumor response to immunotherapy as documented by computerized tomography. Neurological side effects occurred in all patients undergoing treatment and were related to increases in cerebral edema that appeared to be mediated by the immunotherapy. This report demonstrates the present limitations of regional adoptive immunotherapy with LAK cells and IL-2 in the treatment of human glial tumors.

IL-4 regulation of murine lymphokine-activated killer activity in vitro. Effects on the IL-2-induced expansion, cytotoxicity, and phenotype of lymphokine-activated killer effectors

The in vitro incubation of B6 splenocytes with purified, mouse rIL-4 for 4 to 5 days was sufficient to generate lymphokine-activated killer (LAK) activity. In addition, rIL-4 augmented LAK cytotoxic activity when combined with rIL-2, as measured in a 4 h 51Cr-release assay against fresh, syngeneic MCA-sarcoma (MCA-102 and MCA-105) cells. Interestingly, this augmentation was not observed against the cultured YAC-1 target. LAK generation and augmentation of cytotoxicity by rIL-4 was species-specific, because human rIL-4 (up to 20,000 U/ml) failed to elicit these effects in the mouse splenocyte cultures. When 5-day B6 LAK cells (splenocytes incubated in rIL-2 at 1000 U/ml for 5 days) were split and recultured in the combination of rIL-2 plus rIL-4 for 4 additional days at least a twofold greater expansion in cell number resulted compared to similar cells cultured in either rIL-2 or rIL-4 alone. Moreover, LAK cells expanded in rIL-2 plus rIL-4 exhibited substantial increases in in vitro cytolytic activity (on a per cell basis) against MCA-102 and MCA-105 sarcoma cells, but not against YAC-1 targets. FACS analysis or negative selection using Lyt-2 or NK-1.1 mAb plus C revealed no differences in effector phenotype(s) of LAK cells expanded in rIL-2 alone compared to rIL-2 plus rIL-4 to account for the differences observed in both expansion and cytolytic activity by rIL-4. The majority of cells was Thy-1+, Lyt-2+, T3+, and ASGM-1+. However, a marked increase in the granule-associated serine esterase, BLT-E, was found only in LAK cells expanded in the combination of both lymphokines. Collectively, these studies show that rIL-4 has potent regulatory activities on splenic LAK generation, expansion, and cytotoxic function in the mouse.

IL-4 regulation of murine lymphokine-activated killer activity in vitro. Effects on the IL-2-induced expansion, cytotoxicity, and phenotype of lymphokine-activated killer effectors

The in vitro incubation of B6 splenocytes with purified, mouse rIL-4 for 4 to 5 days was sufficient to generate lymphokine-activated killer (LAK) activity. In addition, rIL-4 augmented LAK cytotoxic activity when combined with rIL-2, as measured in a 4 h 51Cr-release assay against fresh, syngeneic MCA-sarcoma (MCA-102 and MCA-105) cells. Interestingly, this augmentation was not observed against the cultured YAC-1 target. LAK generation and augmentation of cytotoxicity by rIL-4 was species-specific, because human rIL-4 (up to 20,000 U/ml) failed to elicit these effects in the mouse splenocyte cultures. When 5-day B6 LAK cells (splenocytes incubated in rIL-2 at 1000 U/ml for 5 days) were split and recultured in the combination of rIL-2 plus rIL-4 for 4 additional days at least a twofold greater expansion in cell number resulted compared to similar cells cultured in either rIL-2 or rIL-4 alone. Moreover, LAK cells expanded in rIL-2 plus rIL-4 exhibited substantial increases in in vitro cytolytic activity (on a per cell basis) against MCA-102 and MCA-105 sarcoma cells, but not against YAC-1 targets. FACS analysis or negative selection using Lyt-2 or NK-1.1 mAb plus C revealed no differences in effector phenotype(s) of LAK cells expanded in rIL-2 alone compared to rIL-2 plus rIL-4 to account for the differences observed in both expansion and cytolytic activity by rIL-4. The majority of cells was Thy-1+, Lyt-2+, T3+, and ASGM-1+. However, a marked increase in the granule-associated serine esterase, BLT-E, was found only in LAK cells expanded in the combination of both lymphokines. Collectively, these studies show that rIL-4 has potent regulatory activities on splenic LAK generation, expansion, and cytotoxic function in the mouse.

Recombinant human tumor necrosis factor mediates regression of a murine sarcoma in vivo via Lyt-2+ cells

The role of an immune response in recombinant-human-tumor-necrosis-factor(rHTNF)-mediated regression of a weakly immunogenic, MCA-106 sarcoma in vivo was examined. C57BL/6 mice bearing established 10-day s.c. tumor were treated with single i.v. doses (8 micrograms) of rHTNF. rHTNF administration resulted in marked hemorrhagic necrosis and subsequent regression of tumor in treated mice. Mice cured of MCA-106 sarcoma by rHTNF specifically rejected a subsequent challenge (5 x 10(5) cells) of the same tumor (P less than 0.01) but not of the antigenically distinct, syngeneic MCA-105 sarcoma. Tumor bearers were depleted in vivo of selective T-cell subsets by the systemic administration of specific monoclonal antibodies before rHTNF therapy. rHTNF-induced regression, but not hemorrhagic necrosis of the MCA-106 sarcoma was blocked in mice depleted of Lyt-2+ cells, but not of L3T4+ cells. The in vivo role of T-cell subsets in rHTNF-mediated tumor regression is discussed.

Prognostic indicators of laparotomy findings in clinical stage I-II supradiaphragmatic Hodgkin's disease

Between July 1968 and July 1986, 915 patients with clinical stage (CS) I and II Hodgkin's disease limited to sites above the diaphragm underwent laparotomy and splenectomy at Stanford University. Fifteen percent were CS I, of whom 76% had cervical/supraclavicular disease, 13% axillary disease, and 9% mediastinal presentations. CS I patients were more likely to be male, were significantly older, and were significantly less likely to have nodular sclerosis (NS) histology than CS II patients. Twenty percent of CS I patients and 30% of CS II patients were pathologically upstaged. No CS I patients were upstaged to pathological stage (PS) IV. Univariate and multivariate analyses of presenting clinical characteristics were performed to predict staging laparotomy findings. CS I women, CS I patients with mediastinal-only disease, and CS I men with either lymphocyte predominance or interfollicular histologies were at low risk for having disease below the diaphragm (5%) or requiring chemotherapy (0%). CS II women who were less than 27 years old and had only two or three sites of disease were also at low risk for upstaging (9%) or requiring chemotherapy (2%). Mixed cellularity histology and male gender were associated with increased risk for subdiaphragmatic disease and require laparotomy; the presence of systemic symptoms was not correlated with laparotomy findings. These results confirm the importance of performing staging laparotomy for the majority of patients who present with supradiaphragmatic Hodgkin's disease if treatment programs are based on the presence and extent of subdiaphragmatic disease. Selected subgroups are at low risk for subdiaphragmatic disease and might be spared laparotomy if they are treated with mantle, paraaortic, and splenic irradiation.

Studies of the mechanisms of toxicity of the administration of recombinant tumor necrosis factor alpha in normal and tumor-bearing mice

Tumor-bearing mice have a greater sensitivity to the acute lethal effects of the administration of high-dose recombinant human tumor necrosis factor alpha (rhTNF-alpha) compared to normal, non-tumor-bearing mice. We studied whether or not the presence of tumor per se was responsible for the enhanced rhTNF-alpha toxicity. Tumor-bearing mice underwent tumor excision or sham operation before the systemic administration of rhTNF alpha at staged times (0.5-24 h) following surgery. There was little survival difference between sham-operated tumor-bearing mice and tumor-bearing mice undergoing tumor excision (at 24 h, treatment with 12 micrograms rhTNF-alpha, survival:sham-operated tumor bearers = 0/12, excised tumor-bearers = 0/12; p2 less than 0.01 compared to non-tumor-bearers). Mice without tumors receiving sham operation, had minimal toxicity (10 of 12 mice surviving). The injection of 3 ml Ringer's lactate i.p. before i.v. rhTNF-alpha therapy increased survival in tumor-bearing animals; following pretreatment with Ringer's lactate 30/42 mice survived 12 micrograms rhTNF-alpha compared to 6/42 surviving a similar rhTNF-alpha dose without hydration (P2 less than 0.001). Since the production of oxygen free-radical metabolites has been postulated to play a role in the acute toxicity of rhTNF-alpha, bismuth subnitrate was used to induce the enzyme metallothionein to act as a natural scavenger for these metabolites. Daily oral bismuth subnitrate treatments improved survival of mice with MCA-106 or MCA-102 sarcoma and of mice without tumors, with higher rhTNF-alpha doses (12-20 micrograms), without reducing the therapeutic effect of rhTNF-alpha against the weakly immunogenic MCA-106 sarcoma. These studies suggest methods for reducing the toxicity of rhTNF-alpha administration in clinical trials.

Overview of interleukin-2 as an immunotherapeutic agent

Interleukin-2 (IL-2) is a lymphokine which has a variety of in vivo immunomodulatory effects. The administration of IL-2 can mediate enhancement of cellular immune responses, induction of lymphocyte proliferation, production of cytokines, and regression of established tumor in animal models. The availability of large quantities of recombinant IL-2 has enabled investigators to examine its therapeutic potential in the treatment of human cancer. Several studies have documented the ability of IL-2 administration to cause durable tumor regression in patients with advanced melanoma and renal cell cancer. Toxicity of therapy is dose related and is mediated by a vascular capillary leak syndrome, lymphocytic infiltration, and the release of cytokines secreted in response to IL-2 administration. The side effects are completely reversible upon cessation of therapy. Future efforts are aimed at increasing the antitumor efficacy and decreasing the toxicity of IL-2 administration.

Heterogeneous lymphokine-activated killer cell precursor populations. Development of a monoclonal antibody that separates two populations of precursors with distinct culture requirements and separate target-recognition repertoires

We developed a monoclonal antibody (mAb) 211, which recognizes the precursors in peripheral blood of lymphokine-activated killer cells (LAK) induced by recombinant interleukin-2 (rIL-2). In conjunction with complement mAb 211 also eliminates natural killer cells (NK) and a majority of the cytotoxic T lymphocytes. B cells and monocytes do not express the 211 antigen. Since mAb 211 recognized such a large percentage of peripheral blood lymphocytes we examined which 211+ subpopulation was the predominant precursor of rIL-2-induced LAK cells using two-color fluoresence-activated cell sorting (fluorescein-conjugated 211 mAb plus phycoerythrin-CD11b). This method identified the 211+/CD11b+ population as the predominant phenotype of the rIL-2-induced LAK precursor. In addition, we directly compared the phenotype of the LAK precursor induced by delectinated T-cell growth factor (TCGF) to that induced by rIL-2. The 211-depleted population, which was devoid of NK cells and LAK precursors (inducible by rIL-2), was capable of generating LAK activity when TCGF was used as the source of lymphokine. LAK cells induced by TCGF from the 211-depleted population lysed a fresh sarcoma and an NK-resistant cultured melanoma tumor target but not the Daudi cell line, which was lysed by rIL-2-induced LAK cells. Lymphoid subpopulations, depleted using NKH1a mAb, behaved similarly, generating high levels of lysis against the two solid tumor targets when cultured with TCGF but not with rIL-2. CD 3-depleted populations showed enrichment for LAK precursors using either rIL-2 or TCGF. These results indicate that while rIL-2-induced LAK precursors cannot be separated from cells with NK activity, TCGF-induced LAK cells can be generated from populations of peripheral blood mononuclear cells without NK activity.

Cardiorespiratory effects of immunotherapy with interleukin-2

The administration of interleukin 2 (IL-2) and lymphokine-activated killer (LAK) cells can mediate the regression of cancer. Treatment with IL-2 is associated with significant cardiorespiratory effects, as well as a leaky capillary syndrome requiring careful fluid management. A mild reversible depression of cardiac function is also associated with IL-2 treatment. All patients treated with recombinant IL-2 alone, with transfer of LAK cells, or with cyclophosphamide between December 1984 and September 1987 (total of 423 treatment courses in 317 total patients) were evaluated as to the development of significant cardiorespiratory toxicity. Of the 423 treatment courses, only 1.8% were associated with severe peripheral edema and only 2.8% and 3.1% respectively, were associated with significant ascites or pleural effusions. Thirty-nine of 423 patients (9.2%) had severe respiratory distress and 27 patients required intubation (6.4%). Cardiovascular effects included tachycardia and hypotension requiring vasopressor administration in 65% and intravenous (IV) fluid administration. Weight gain greater than or equal to 10% of body weight was noted in 32% of the 423 patients. Arrhythmias were primarily supraventricular (9.7%) and responded well to conventional medical treatments. Angina or ischemic changes were noted in 2.6% of patients and myocardial infarction in 1.2%. IL-2 caused peripheral vasodilation, with a significant decrease in peripheral vascular resistance (2,254 +/- 398 v 1,303 +/- 351 dyne.s.cm-5, P less than .0001), and an increase in heart rate (66.2 +/- 10 v 104.3 +/- 9.6 beats/min, P less than .0001). There was also evidence of mild cardiac dysfunction, with a significant decrease in the left ventricular stroke work (LVSW) index (P less than .0001) and ejection fraction (LVEF) (from 58% +/- 10% to 52% +/- 9%, P less than .03). A repeat LVEF performed after 1 to 3 months, had returned to baseline values (60% +/- 10%). A mean 64% increase in the rate of disappearance of radioactive iodine (125I) albumin (P less than .05) consistent with the development of a leaky capillary syndrome was noted. Patients with underlying cardiorespiratory diseases may be at greater risk during IL-2 administration and should not be selected to undergo this treatment.

Combined effects of interferon alpha and interleukin 2 on the induction of a vascular leak syndrome in mice

Immunotherapy with interleukin 2 (IL-2) alone or in combination with lymphokine-activated killer cells can mediate tumor regression in mice and in man. Further dose escalation of IL-2 along with lymphokine-activated killer cells has been prevented by the development of a vascular leak syndrome produced by IL-2. Because we have found that interferon alpha (IFN-alpha) or tumor necrosis factor (TNF-alpha) has synergistic antitumor effects when administered together with IL-2, we have tested the vascular leakage induced by these lymphokine combinations. We used a murine model to quantify vascular leakage by measuring the extravasation of 125I-albumin from the intravascular space as well as the wet and dry lung weights after treatment with different cytokines. Cytokines (or Hanks balanced salt solution) were administered to C57BL/6 mice and 4 h after the last injection the vascular leak was quantified. IFN-alpha alone did not cause extravasation of radiolabel or increase in wet lung weights, though when given in combination with IL-2, significantly greater extravasation (P less than 0.01) as well as increase in lung water weights (P less than 0.05) was observed compared to the response in mice treated with IL-2 alone. IFN-alpha in combination with IL-2 induced significant vascular leakage earlier than the response induced by IL-2 alone. For example treatment with IFN-alpha and IL-2 induced accumulation of 14,674 +/- 605 cpm in the lungs at day 1 while IL-2 alone induced 12,340 +/- 251 cpm. The degree of vascular leakage was highly related to the dose of IFN-alpha administered along with IL-2 and increased vascular leak syndrome was evident even at low doses (5000 units) of IFN-alpha. Immunosuppression of mice by pretreatment irradiation (500 rad) markedly decreased the development of vascular leak syndrome induced by IL-2 and IFN-alpha. Interestingly IFN-gamma and TNF-alpha did not induce vascular leakage in the lungs when given alone, and did not add or synergize with IL-2 in causing the syndrome. Thus the administration of IFN-alpha in combination with IL-2 produces a dose-limiting vascular leakage that is more severe than that caused by IL-2 alone, and may be mediated, directly or indirectly by host radiosensitive cells.