Journal of immunotherapy with emphasis on tumor immunology : official journal of the Society for Biological Therapy最新文献

To evaluate the effect of two distinct adoptive immunotherapies, tumor-specific cytotoxic T-cell (CTL) therapy and lymphokine-activated killer (LAK) cell therapy, the clinical responses of patients with stage IV primary hepatocellular carcinoma (HCC) treated with these therapies were studied. Of 18 patients treated with CTL, 3 had complete regression (CR), 2 had partial regression, and 3 had minor regression (MR). Their median survival was 21 months after the end of therapy, and 1 CR patient survived for > 6 years. On the other hand, in the LAK-cell-treated group of eight patients, four had MR and their median survival was only 2 months. No survival was observed 27 months after the end of LAK cell therapy. These results indicate that tumor-specific CTL therapy is more effective than LAK cell therapy and that it might be a promising therapeutic tool for advanced HCC patients.

Renal cell carcinoma (RCC) is relatively resistant to chemotherapy and radiotherapy, whereas treatment with biologics has achieved limited success. Although monoclonal antibodies able to recognize human RCC have been identified, most induce little complement-dependent cytotoxicity or antibody-dependent cellular cytotoxicity (ADCC), and thus are of limited potential as therapeutic modalities in their natural conformation. We evaluated a human/ mouse chimeric derivative of the previously described G250 murine monoclonal antibody (mAb), reactive with RCC, to identify a reagent for potential immunotherapy. This chimeric antibody (ch-G250) is composed of the murine variable region from the G250 mAb, which recognizes a tumor-associated antigen expressed on 95% of primary and 86% of metastatic renal cell carcinomas. The constant region of the ch-G250 is comprised of the human IgG1 isotype domains. This chimeric antibody does not bind to normal renal tissue or other normal human tissues, with the exception of gastric mucosal cells and large bile-duct epithelium. Clinical radiolocalization studies have demonstrated the relative tumor-targeting potential of this radiolabeled antibody. This ch-G250 antibody facilitated potent ADCC against several RCC lines when using in vitro and in vivo interleukin-2 (IL-2)-activated peripheral blood mononuclear cells obtained from healthy control donors and patients with cancer, respectively. This lymphocyte-mediated ADCC was specific for RCC cells recognized by the ch-G250 antibody. Using flow cytometry, we found that the level of ADCC was directly related to the degree of binding of ch-G250 to the renal cell target. These in vitro data suggest that this antibody may improve efficacy of IL-2 therapy by targeting cytokine-activated effector cells directly to the tumor and facilitating in vivo ADCC. Clinical studies combining this chimeric antibody with IL-2 treatment will be needed to test the antitumor effects of this ADCC effect in vivo.

Stage IIIb non-small-cell lung cancer (NSCLC) has a poor prognosis. The median survival is approximately 6 months, and only 30% of patients are alive 1 year after diagnosis. The need for effective treatment is evident. The aim of this study was to evaluate whether the infusion of tumor-infiltrating lymphocytes (TILs), isolated from resected tumor, expanded in vitro and injected together with recombinant Interleukin-2, is feasible and may at least partially modify the poor prognosis in these patients. The infusion of TILs, derived from surgically resected NSCLC and expanded in vitro, together with subcutaneous (s.c.) injections of recombinant interleukin-2 (rIL-2) was attempted in a group of 11 patients. Treated patients were infused i.v. with in vitro expanded TILs (from 4 to 70 x 10(9) cells), and rIL-2 was injected s.c. at doses varying from 61 to 378 x 10(6) IU. Toxic side effects (fever and, in some cases, hypotension) were observed and limited the dose of rIL-2 infused. Follow-up was continued for 40 months. The mean survival time was 13.8 months. Three of five TIL-treated patients with residual disease have no evident disease after 1 year, and two of them are still alive and have no evidence of disease after 40 months. This pilot study suggests that the infusion of in vitro expanded TILs, derived from surgical samples, is feasible and seems to prolong overall survival and to control the residual disease in patients with advanced NSCLC.

Previous primate and rodent studies suggested that interleukin-1 alpha (IL-1 alpha) caused changes in the secretion of pituitary, adrenal, thyroid, and gonadal hormones, as well as acute-phase reactants. Plasma samples were obtained after IL-1 alpha and beta treatment in cancer patients to document the changes in endocrine function suggested by the animal models. Successive groups of patients were treated at IL-1 alpha doses of 0.01, 0.03, 0.1, 0.3, and 1.0 microgram/kg, given daily as a 15-min intravenous bolus. IL-1 beta was given at 0.1 microgram/kg by the same route and time course. After the first dose of IL-1, statistically significant elevations of a.m. and p.m. cortisol, growth hormone (GH), and prolactin (PRL) occurred. Thyroid-stimulating hormone (TSH) and C-reactive protein (CRP) were elevated by the sixth treatment day. Testosterone decreased significantly in male patients. Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were more variable but decreased in most patients. The changes in cortisol, GH, PRL, TSH, CRP, FSH, LH, and testosterone resolved after treatment and did not result in clinically apparent endocrinopathies. Bolus doses of IL-1 alpha and beta cause significant changes in many endocrine laboratory parameters and influence the in vivo activities of multiple homeostatic endocrine functions in human beings.

Combination therapy with systemically administered interleukin-2 (IL-2) and tumor infiltrating lymphocytes (TIL) demonstrates significant clinical activity in some patients with metastatic renal cell carcinoma (RCC). The objective of this study was to identify predictors of therapeutic response in patients with IL-2- and TIL-based immunotherapy. We characterized and compared immunologic properties of tumors, TILs, peripheral blood lymphocytes (PBLs) and sera of responding (R, n = 8) with nonresponding patients (NR, n = 9). Before undergoing nephrectomy, responding patients exhibited a higher percentage of circulating natural killer (NK) cells (CD56+ CD3-) (43 +/- 20%) as compared with nonresponders (18 +/- 16%) (p < 0.01). After nephrectomy, the CD56+ CD3-/CD56- CD3+ ratio in responding patients (pre: 2.60 +/- 2.24; post: 0.28 +/- 0.19; p < 0.05) significantly decreased and was similar to that of patients not responding to therapy (0.42 +/- 0.36). Sera from patients responding to immunotherapy, obtained before and after completion of therapy, contained natural killer (NK)-enhancing factor(s) that significantly enhanced the proliferation (3.2 x 10(3) +/- 25%/ 3.6 x 10(3) +/- 13% counts/min) and cytotoxicity [17.6 +/- 4.0/18.0 +/- 1.9 lytic units (LU)] of fresh PBLs as compared with normal serum (1.8 x 10(3) +/- 8% counts/min; 13.4 +/- 2.5 LU) or sera from nonresponders (1.6 x 10(3) +/- 25%/1.5 x 10(3) +/- 20% counts/min; 8.3 +/- 5.9/6.8 +/- 4.8 LU). In contrast to noncultured tumor suspension, IL-2 cultivation induced TIL growth, cytotoxicity, and multicytokine synthesis, and a complete clearance of tumor cells. No significant differences were observed between responders and nonresponders in the in vitro characteristics of tumor/TIL, which include the degree of intratumoral lymphocytic infiltrate, TIL expansion, specific lysis of autologous tumor, phenotype, expansion time, quantity of TIL infused, cytokine release, and degree of tumor aggressiveness. We conclude that clinical response to TIL and IL-2-based immunotherapy is associated with patients' baseline natural immune status. The percentage of circulating NK cells and the presence of serum NK-cell-enhancing factors may serve as potential predictors of response in patients with advanced RCC. The in vitro study of RCC-TIL suggests that activated TIL may provide a synergistic effect to that of administered IL-2 on activation of cellular immune response in situ, rendering a tumor eradication, while the clinical outcome is largely dependent on the pretreatment immune status of patient.

The antitumor effects of CD40 and CD20 monoclonal antibodies (mAbs) were compared on various human B-cell lymphomas by using both in vitro and in vivo assays. Anti-CD40 directly inhibited the proliferation of human B-cell lymphomas in vitro, whereas anti-CD20 exerted no inhibitory effects on the growth of any lymphoma tested. These lymphomas were then injected into immunodeficient mice to examine the antitumor efficacy of these unconjugated mAbs in vivo. This xenogeneic model was used in the evaluation of various potential therapeutic agents against human cancers in an in vivo setting. Surprisingly, in contrast to its negligible effects on lymphoma growth in vitro, anti-CD20 was more efficacious than anti-CD40 in promoting the survival of mice bearing some but not all lymphoma lines. To determine whether the antitumor effects of these mAbs were direct or indirect in vivo, we concurrently treated tumor-bearing mice with mAbs to the murine Fc receptor to block antibody-dependent cell-mediated cytotoxicity (ADCC). When these neutralizing antibodies against Fc receptors were administered at the same time as mAb treatment, the antitumor effects of anti-CD20 in vivo were completely abrogated, whereas anti-CD40 treatment, although also diminished, still provided significant antitumor effects. These results indicate that the in vivo antitumor activity of the murine anti-human CD20 mAb was primarily due to ADCC by murine effector cells, which may not translate into comparable effects in humans. By contrast, anti-CD40 may be of potential clinical use in the treatment of lymphomas in humans because of its additional direct anti-proliferative effects. The results also demonstrate a possible difficulty in accurately evaluating the potential clinical efficacy of murine antibodies against human tumors in a human/mouse model system. Murine monoclonal anti-human antibodies may produce greater effects in human/mouse xenogeneic models, in which they are more likely to elicit host effector systems than when used in vivo in humans.

We have developed a new reagent for inducing in vivo T-cell depletion and have tested this reagent in rhesus monkeys. The reagent is an anti-CD3 epsilon immunotoxin based on a diphtheria toxin binding-site mutant, CRM9. After administration to monkeys, T cells are depleted from both the blood and lymph node compartments to < 1% of their initial values. T-cell depletion is associated with transient immunosuppression, as judged by delayed rejection of RhLA-mismatched skin allografts. T cells are repopulated in both compartments; however, the rate of repopulation is age dependent. The rate is rapid in juvenile animals (12 days) and requires > 30 days in old animals. The correlation between repopulation rate and age suggests that the repopulation is thymus dependent and that the repopulated T cells are probably naive T cells. This reagent should be a valuable tool in studying the role of memory T cells in rhesus models of autoimmune diseases and protocols of tolerance induction after organ transplantation.

Plasma membrane vesicles isolated from tumor cells can be incorporated onto 5-microns diameter microspheres and antigen in this form, termed large multivalent immunogen (LMI), augments generation of tumor-specific cytotoxic T lymphocyte (CTL) responses in vivo. Treatment of mice with LMI at the time of challenge with tumor significantly reduced growth of several tumors in their syngeneic hosts. Our report describes the effects of LMI on established progressing tumors, including P815 solid tumor and two fibrosarcomas in a lung-metastasis model. Treatment of mice bearing established tumors (7 to 12 days) with LMI alone did not significantly reduce tumor growth or extend host survival, but highly synergistic effects of combined treatment with cyclophosphamide (Cy) and LMI were found. Cy alone reduced the size of P815 solid tumors, but within a few days, the tumors began to grow progressively, and survival was only marginally extended. However, Cy followed 2 to 3 days later by a single injection of LMI resulted in prolonged reduction of tumor growth and significant extension of survival; in some experiments, tumors became undetectable in the majority of treated mice, and the mice survived indefinitely. Essentially the same results were obtained in experiments examining survival of mice bearing established MCA-203 fibrosarcoma. LMIs were uniquely effective in acting synergistically with Cy; antigen in the form of irradiated tumor cells or plasma membrane in adjuvant were ineffective, and free plasma-membrane antigen (not on microspheres) had only marginal effects. There has been considerable interest in the possibility of using tumor antigen to enhance tumor-specific immune responses, and clinical trials using this approach are showing some promise. The results described here suggest that altering the form of antigen by purifying plasma membranes and incorporating them onto microspheres might significantly improve the efficacy of tumor immunotherapy with antigen.

We report on the immuno-oncologic analysis and treatment of a remarkable case of disseminated CD30+ anaplastic non-Hodgkin's lymphoma. Its clinical course was characterized by repeated spontaneous regressions, which were probably due to a T-cell-mediated anti-lymphoma immune reaction, as tumor-infiltrating T lymphocytes were consistently observed in sections of lymphoma lesions and found to express high-affinity receptors for interleukin-2 (IL-2). This marker may be particularly suitable to predict a response to low-dose recombinant IL-2 (rIL-2), as confirmed in this case by prompt lymphoma regression after regional rIL-2 perfusion of a cutaneous lesion and by an impressive overall response to systemic rIL-2 treatment. Despite the very low dose of rIL-2, 600,000 IU/24 h as a continuous i.v. infusion, systemic treatment was complicated by generalized capillary leakage and life-threatening unilateral drowning of the lymphoma-infiltrated left lung.

Interleukin-2 (IL-2) is a cytokine with proven activity against metastatic renal cell carcinoma (RCC) and malignant melanoma (MM). The intravenous administration of high-dose IL-2 is limited by important cardiovascular side effects such as hypotension, fluid retention, arrhythmias, and myocardial ischemia, which often cause dose reduction and/or treatment withdrawal. The occurrence of these toxic events is not predicted by routine pretreatment examinations. The aim of the present study was to test the reliability of serial echocardiography in predicting subsequent cardiac adverse effects in patients undergoing IL-2 administration. In 19 patients (15 men, 4 women; median age: 51 years, range 27-71 years; 10 affected by metastatic RCC and 9 affected by MM) we performed two-dimensional and Doppler echocardiography before and immediately after 28 continuous intravenous infusions (CIVI) of IL-2 at the dose of 18 MIU/m2/day for 4 days. Left ventricular systolic function and the diastolic transmitral flow pattern were assessed before and after IL-2 administration. Significant changes of two indexes of left ventricular filling were noted: a decrease of the ratio of maximal flow velocity in early diastole to that in late diastole (E/A) (basal: 1.12 +/- 0.46, mean +/- SD; posttreatment: 0.83 +/- 0.27; p < 0.01) and an increase of the percentage of the atrial contribution to left ventricular filling (basal: 37.75 +/- 11.58%; posttreatment: 49.43 +/- 16.48%; p < 0.01). Eight major cardiovascular events causing IL-2 infusion withdrawal were observed (two ischemic electrocardiographic modifications, three grade III-IV hypotension, one atrial fibrillation, one pericardial effusion, one acute heart failure). These major cardiovascular events were observed more often when an abnormal basal E/A ratio < 1.0 (p < 0.05) was found. We conclude that Doppler transmitral flow pattern analysis before and subsequent to IL-2 infusion is a useful and easily available procedure for the monitoring of cardiac modifications during CIVI IL-2 administration. It might also predict a major cardiovascular event during IL-2 administration. Patients with basal E/A ratio < 1.0 should be more carefully monitored during treatment and/or should be treated with lower IL-2 doses to avoid cardiovascular toxicity.