Advanced mesospheric temperature mapper for high-latitude airglow studies.

Over the past 60 years, ground-based remote sensing measurements of the Earth's mesospheric temperature have been performed using the nighttime hydroxyl (OH) emission, which originates at an altitude of ∼87 km. Several types of instruments have been employed to date: spectrometers, Fabry-Perot or Michelson interferometers, scanning-radiometers, and more recently temperature mappers. Most of them measure the mesospheric temperature in a few sample directions and/or with a limited temporal resolution, restricting their research capabilities to the investigation of larger-scale perturbations such as inertial waves, tides, or planetary waves. The Advanced Mesospheric Temperature Mapper (AMTM) is a novel infrared digital imaging system that measures selected emission lines in the mesospheric OH (3,1) band (at ∼1.5 µm) to create intensity and temperature maps of the mesosphere around 87 km. The data are obtained with an unprecedented spatial (∼0.5 km) and temporal (typically 30″) resolution over a large 120° field of view, allowing detailed measurements of wave propagation and dissipation at the ∼87 km level, even in the presence of strong aurora or under full moon conditions. This paper describes the AMTM characteristics, compares measured temperatures with values obtained by a collocated Na lidar instrument, and presents several examples of temperature maps and nightly keogram representations to illustrate the excellent capabilities of this new instrument.

A Phase 1 clinical trial of Hantaan virus and Puumala virus M-segment DNA vaccines for haemorrhagic fever with renal syndrome delivered by intramuscular electroporation.

Haemorrhagic fever with renal syndrome (HFRS) is endemic in Asia, Europe and Scandinavia, and is caused by infection with the hantaviruses Hantaan (HTNV), Seoul (SEOV), Puumala (PUUV), or Dobrava (DOBV) viruses. We developed candidate DNA vaccines for HFRS expressing the Gn and Gc genes of HTNV or PUUV and evaluated them in an open-label, single-centre Phase 1 study. Three groups of nine participants each were vaccinated on days 0, 28 and 56 with the DNA vaccines for HTNV, PUUV, or a mixture of both vaccines using the Ichor Medical Systems TriGrid Intramuscular Delivery System. All vaccinations consisted of a total dose of 2.0 mg DNA in an injected volume of 1 mL saline. For the combined vaccine, the mixture contained equal amounts (1.0 mg) of each DNA vaccine. There were no study-related serious adverse events. Neutralizing antibody responses were measured by a plaque reduction neutralization test. Neutralizing antibody responses were detected in five of nine and seven of nine individuals who completed all three vaccinations with the HTNV or PUUV DNA vaccines, respectively. In the combined vaccine group, seven of the nine volunteers receiving all three vaccinations developed neutralizing antibodies to PUUV. The three strongest responders to the PUUV vaccine also had strong neutralizing antibody responses to HTNV. These results demonstrate that the HTNV and PUUV DNA vaccines delivered by electroporation separately or as a mixture are safe. In addition, both vaccines were immunogenic, although when mixed together, more participants responded to the PUUV than to the HTNV DNA vaccine.

GM-CSF safety and effects in the management of advanced/refractory multiple myeloma patients: a phase I trial.

PURPOSE: Some limitations of effective therapy in multiple myeloma include the low growth fraction of the malignant plasma cells, multi-drug resistance, and the presence of other concurrent diseases in this patient population. A phase I study was conducted to evaluate the toxicity of granulocyte macrophage colony stimulating factor (GM-CSF) in myeloma patients as well as the potential effect on the plasma cell labeling index (PCLI). Relapsed patients with multiple myeloma were eligible. METHODS: The first phase of this trial assessed the toxicity (including the effect on disease progression) of escalating doses (125-500 microg/m2 SC, days 1-5) of GM-CSF, and the effects of this cytokine on PCLI. Patients whose PCLI doubled and increased to > or = 1.7% were treated with chemotherapy including cyclophosphamide, vincristine, prednisone, and GM-CSF. Twenty-two patients were enrolled. RESULTS: The toxicity of GM-CSF was mild, and no dose-limiting side effects were seen. Twenty-five percent of patients (5/20) achieved the target PCLI, and 4/5 proceeded to receive chemotherapy. No relationship of GM-CSF dose to increases of the PCLI was noted. All patients who received chemotherapy responded. CONCLUSIONS: GM-CSF has acceptable toxicity in patients with multiple myeloma and produced increases of PCLI in selected individuals. Further studies of GM-CSF alone or in combination with chemotherapy are indicated.

Phase I and II trials of subcutaneously administered rIL-2, interferon alfa-2a, and fluorouracil in patients with metastatic renal carcinoma.

PURPOSE: A phase I followed by a phase II trial utilizing rIL-2, IFN alpha, and 5-FU were conducted in patients with unresectable and/or metastatic renal cell carcinoma. METHODS: Treatment consisted of: rIL-2 at 5.0 x 10(6) IU/m2 SQ on days 1-5 for 4 weeks, rHUIFN alpha-2a at 5.0 x 10(6) U/m2 SQ on days 1, 3, and 5 for 4 weeks, and 5-FU by IV bolus on days 1-5 during week 1. In the phase I study, patients were treated at varying doses of 5-FU: I-none, II-250 mg/m2, III-300, and IV 375. A phase II trial was then conducted utilizing the same schedule and maximum tolerated dose (MTD) for 5-FU. RESULTS: Twenty patients were entered into the phase I trial. Dose-limiting toxicity included grade III nausea and vomiting, and one sudden cardiac death. The MTD for 5-FU was determined to be 300 mg/m2. In the phase II trial, a median of two cycles of therapy was administered to 25 evaluable patients. Toxicity was moderate and consisted primarily of fevers, chills, fatigue, nausea/vomiting, and anorexia. Grade IV thrombocytopenia, consistent with ITP, developed in one patient each on the phase I and phase II trial. Seven partial responses were seen among 25 patients treated in the phase II trial for a 28% (CI 12-49%) response rate. CONCLUSIONS: The addition of 5-FU to rIL-2 and rHuIFN alpha-2a appears to increase the toxicity of this therapy. Randomized trials will be required to determine if efficacy is enhanced.

Interspecific and geographical variation in the sequence of rDNA expansion segment D3 of Ixodes ticks (Acari: Ixodidae).

The base sequence of the rDNA D3 expansion segment and flanking H14 stem varies between six species of Ixodes ticks (Acari: Ixodidae) where only 33 invariant sites occur among sequences of 123-203 bases in length. Multiple copies of D3 were sequenced from localities across the geographical ranges of four species to investigate deep population genetic structure. Two species, I. pacificus, from western North America, and I. ricinus, from Europe, have no sequence variation indicating a lack of deep genetic structure. One species, I. scapularis, from eastern North America has two forms of the D3 sequence that are distributed differently among northern vs. southern populations, suggesting recent divergence and hybridization. I. persulcatus, from Eurasia, has sequence variation between localities of the order of that observed between other species, suggesting a long history of population isolation and deep genetic structure. With the exception of I. scapularis, sequence variation was not observed within localities. This indicates that cellular processes underpinning concerted evolution have homogenized populations and species for particular rDNA sequence variants.

Evolution of transcript structure and base composition of rDNA expansion segment D3 in ticks.

Four to thirty-two copies of the rDNA 28S gene expansion segment D3 and flanking H14 stem were sequenced in six species of ticks (Ixodes: Ixodidae: Acari). Sequence match among species varied from 66% to 97%. Sequence length averaged 130 bases in I. persulcatus across eight Eurasian sites and averaged 186 bases in five other species across 19 Eurasian and North American sites. The difference in length represents one or more deletions totalling about 60 bases that correspond to stems S3 or S4 of the folded transcript. The typical transcript conformation was observed as one possible low energy structure in the five species of longer D3. The structure entails a basal loop with four stem/loop structures, S1-S4 (moving 5' to 3') atop stem H14. A secondary structure lacking S4 but possessing all other putative standard features of the D3 transcript is possible with the shorter I. persulcatus sequences. Interspecific sequence differences occur at higher frequency in loops and bulges vs. complementary pairing regions of stems. Insertion/deletion events (indels) and base substitutions accounted equally for sequence differences. Indels are flanked by similar sequences, suggesting that they occur by slippage during replication. The D3 of Ixodes species is composed of a degenerate set of subrepeats. Thus, unequal exchange among subrepeats may have caused the reduction in length of the I. persulcatus D3. Compensatory base substitution and compensatory insertion/deletion events are indicated by the failure of mutations to affect secondary structure. Transversions accounted for 64% of sequence differences and were biased toward the gain of G and U and the loss of A and C. This bias could re-establish intramolecular base pairing when disrupted by insertions or deletions that shift one side of a stem relative to the other. The distribution of sequence differences, biased substitution, and conservation of transcript conformation in D3 suggest selective constraint.

A phase II pharmacodynamic study of pyrazoloacridine in patients with metastatic colorectal cancer.

PURPOSE: To perform a phase II trial of pyrazoloacridine (PZA), a novel DNA intercalator, in patients with metastatic colorectal carcinoma and no previous therapy. METHODS: PZA was administered at a dose of 750 mg/m2 intravenously over 3 h every 21 days. Pharmacokinetic studies to determine PZA plasma concentrations were performed. RESULTS: No responses were seen in 14 response-evaluable patients. Patients received a median of two cycles of PZA (range 1-6). Toxicity included neutropenia and neurologic side-effects, which were > or = grade III in 73% and 14%, respectively. High plasma concentrations of PZA (Cmax) correlated with low neutrophil counts (P = 0.04). CONCLUSIONS: PZA is inactive at this dose and schedule in colorectal cancer, and produces moderately severe toxicity.

Phase 1 trial of subcutaneous IL-6 in patients with refractory cancer: clinical and biologic effects.

The authors evaluated the clinical and biologic effects of human recombinant interleukin-6 (rhIL-6) in patients with refractory cancer. A phase 1 trial using escalating doses of rhIL-6 (1-50 microg x kg(-1) x d(-1), Monday through Friday for 4 weeks) was performed in 30 patients. Toxicity was moderate and the maximum tolerated dose was determined to be 25 microg x kg(-1)x d(-1) based on cardiac and neurocortical toxicity in one patient each and thrombocytosis (platelets > 800,000/microL) in three patients. One patient with non-small-cell lung cancer had a partial response after three cycles of therapy. The biologic effects of rhIL-6 included anemia and dose-related thrombocytosis. Various proinflammatory activities were induced and included dose-related cyclical increases in peripheral blood monocytes and the CD14+/CD45RB+ +/- CD16C+ mononuclear cell populations. These increases were accompanied by increased levels of C-reactive protein, serum neopterin, and type I soluble tumor necrosis factor receptor. In contrast, rhIL-6 did not affect lymphocyte numbers or function (cytotoxicity, cytokine levels, immunoglobulin levels), with the possible exception of IL-2Ralpha mRNA induction in peripheral blood lymphocytes. rhIL-6 has pleiotropic proinflammatory actions in vivo and moderate toxicity when administered as long-term therapy.

Phase II trial of liposomal doxorubicin (Doxil) in advanced soft tissue sarcomas.

PURPOSE: To assess the objective response rate, toxicity experienced, progression-free survival, and overall survival of patients with previously untreated advanced soft tissue sarcomas treated with a liposomal doxorubicin formulation (Doxil). METHODS: Patients with metastatic or recurrent soft tissue sarcoma who had received no prior chemotherapy for advanced disease were treated with liposomal doxorubicin (Doxil) according to a two stage accrual design. Doxil was administered at 50 mg/m2 every 4 weeks. A total of 15 patients were treated and are evaluable for response and toxicity. RESULTS: The male/female ratio was 7/8, the median age was 60 years (34-75) and the ECOG performance status was 0-1 in >90% of patients. Leiomyosarcoma (7/15) and malignant fibrous histiocytoma (2/15) were the most common histologic diagnoses. No objective responses were observed in the 15 evaluable patients. No lethal toxicity occurred. Grade 3-4 leukopenia or neutropenia were reported in 3/15 (20%) patients. Grade 3 mucositis or hand-foot syndrome occurred in 2/15 (13%) and 1/15 (7%) patients respectively and seemed more severe in older patients. The median time to progression was 1.9 months (range 0.9-6.2). Twelve patients have now died. The Kaplan-Meier estimate of median overall survival is 12.3 months. As called for in the study design, accrual was terminated because no responses were obtained in the first 15 patients. CONCLUSION: Though well-tolerated, Doxil given according to this dose and schedule to patients with advanced soft tissue sarcoma had no significant therapeutic activity. A correlation between older age and skin/mucosal toxicity of Doxil is suggested in this study but needs confirmation. Future investigations of Doxil in soft tissue sarcomas should use a different schedule and dose.

Phase I trial of exisulind (sulindac sulfone, FGN-1) as a chemopreventive agent in patients with familial adenomatous polyposis.

Exisulind (sulindac sulfone; FGN-1), a metabolite of sulindac without known effects on prostaglandin synthesis, can promote apoptosis and inhibit tumorigenesis in preclinical systems. We performed a Phase I trial of this compound in patients with familial adenomatous polyposis (FAP) to examine the tolerability and safety of this drug in the cancer chemoprevention setting. Six patients each were treated with exisulind at doses of 200, 300, and 400 mg p.o. twice a day. Reversible hepatic dysfunction was noted in four of six patients treated at the 400-mg p.o., twice-a-day dose level, but in only one to two of six patients treated at each of the lower dose levels. The serum half-life of exisulind was 6-9 h; little drug accumulation was noted over time. A nonsignificant trend toward increased apoptosis in polyps was noted at the maximum tolerated dose, but no decrease in polyp numbers or significant effects on cellular proliferation was noted. After treatment, polyps tended to display a "halo" appearance grossly and mucinous differentiation histologically. The maximum safe dose of exisulind is 300 mg p.o. twice a day in patients with subtotal colectomies. Reversible hepatic dysfunction limits further dose escalation. A decrease in polyp numbers could not be demonstrated, but the trend toward increased apoptosis at the MTD and the observation of mucinous change histologically suggest that further investigation of drugs of this class might be warranted.

Interferon-gamma and CXC chemokine induction by interleukin 12 in renal cell carcinoma.

Interleukin 12 (IL-12) is known to play an important role in the development of an antitumor response. Its activity has been shown to be dependent upon the intermediate production of IFN-gamma and the influx into the tumor of CD8 lymphocytes. In a murine model, tumor regression induced by IL-12 treatment correlated with IFN-gamma, IP-10, and Mig expression in the tumor bed and was abrogated by antibodies to both chemokines. Here we examined the effects of rHuIL-12 on IFN-gamma and CXC chemokine gene expression in patients with renal cell carcinoma (RCC) in an attempt to determine whether a similar series of molecular events leading to IL-12-mediated tumor regression in mice is also detectable in humans. As in the murine RENCA model, cultured RCC cells themselves could be induced by IFN-gamma to synthesize IP-10 and Mig mRNA. Explanted RCC produced IFN-gamma and IP-10 mRNA in response to IL-12 treatment, which was consistent with the finding that biopsied RCC tumors from IL-12-treated patients also variably expressed augmented levels of those molecules after therapy. Although Mig mRNA was present in the majority of biopsied tumors prior to treatment, both the Mig and IP-10 chemokines as well as IFN-gamma were induced in the peripheral blood mononuclear cells of IL-12-treated patients. Skin biopsies of IL-12-treated patients also all synthesized IP-10 mRNA. This study demonstrates that recombinant human IL-12 therapy of patients with RCC has the potential to induce the expression of gene products within the tumor bed that may contribute to the development of a successful antitumor response.

Approaches to managing carboplatin-induced thrombocytopenia: focus on the role of amifostine.

Thrombocytopenia is a significant problem for patients receiving prolonged or aggressive chemotherapy for malignancy. For carboplatin, it is the predominant dose-limiting toxicity and it is cumulative in nature. A number of agents have been evaluated for efficacy in reducing the problem of thrombocytopenia. Some have proved valueless and have been discarded. Others (eg, recombinant thrombopoietin) are under current study, and one (interleukin-11 or oprelvekin) is now commercially available. In addition, the currently available cytoprotectant, amifostine (Ethyol; Alza Pharmaceuticals, Palo Alto, CA/US Bioscience, West Conshohocken, PA), has been shown to reduce the severity and duration of thrombocytopenia caused by carboplatin. Because of the short half-life of amifostine relative to that of carboplatin, multiple doses of amifostine have been administered in conjunction with carboplatin. The optimal dosing regimen with amifostine and carboplatin needs to be further evaluated in clinical studies. Future trials will also expand these observations to carboplatin-containing combination chemotherapy regimens and will further define the role of amifostine as a multilineage bone marrow protectant. The ability of amifostine to demonstrate multilineage bone marrow protection differentiates it from currently available growth factors and fulfills a medical need, including reducing the need for platelet transfusions and maintaining the desired chemotherapy dose intensity.

Signal transduction abnormalities in T lymphocytes from patients with advanced renal carcinoma: clinical relevance and effects of cytokine therapy.

Studies have demonstrated abnormalities of the CD3/T-cell antigen receptor (TCR) and pathways of signal transduction in T lymphocytes from animals and patients with advanced malignancy. Diminished expression of TCRzeta and p56(lck) that are associated with the TCR and reduced nuclear localization of RelA containing nuclear factor kappaB (NFkappaB) complexes have been noted. These defects have been described in T cells from patients with malignant melanoma, renal cell carcinoma (RCC), ovarian cancer, and colorectal cancer. Preliminary observations also indicate possible correlation with clinical variables such as stage in selected instances. To further characterize altered expression of TCRzeta, p56(lck), and impaired activation of NFkappaB, T lymphocytes were obtained from 65 patients with RCC, the majority of whom were receiving combination cytokine therapy [interleukin (IL)-2, IFN alpha-containing regimens] and 37 control individuals. In 29 of these patients, levels of TCRzeta and p56(lck) were determined by Western blots of T-cell lysates and semiquantitated using densitometry. Relative levels were then correlated with a series of clinical variables including response to therapy, performance status, survival, disease sites, age, and others. In another group of 28 patients (three individuals from the first group), the frequency of abnormal NFkappaB activation was studied using electrophoretic mobility shift assays after activation of T cells with phorbol myristate acetate/ionomycin or anti-CD3 monoclonal antibody. Changes in these signaling molecules during cytokine treatment were also investigated. TCRzeta and p56(lck) were detected in the peripheral blood T cells in 27 of 29 patients, and overall, reduced levels were noted visually in 12 of 29 (41%) and 13 of 29 (45%) individuals, respectively. When levels were semiquantitated using densitometry, significant decreases of TCRzeta (P = 0.029) and p56(lck) (P = 0.029) but not CD3epsilon (P = 0.131), compared with control levels, were found. In patients treated with IL-2/IFN alpha-based therapy, relative levels of TCRzeta increased significantly (P = 0.002) on day 15 of cycle one compared with the baseline. Correlations of TCRzeta or p56(lck) levels with response or disease variables, except for lower TCRzeta levels (P < 0.001) in the presence of bone metastases, were not found. Abnormal NFkappaB activation after stimulation with phorbol myristate acetate/ionomycin and/or anti-CD3 monoclonal antibody was found in 59% of patients (17 of 28) and was not accounted for by the advanced age of the study cohort. Activation of NFkappaB in peripheral blood T cells was inducible during cytokine therapy in four of six individuals who displayed impaired NFkappaB activity prior to therapy. Moreover, impaired activation of NFkappaB does not appear linked to a reduction of TCRzeta expression, because in five patients, normal TCRzeta levels were present although kappaB binding was not inducible. In the majority of patients with advanced RCC, peripheral blood T cells express TCRzeta and p56(lck), and in a subset, reduced levels of these TCRzeta associated molecules are seen that may increase during cytokine-based therapy. Abnormal activation of NFkappaB is also present in >50% of patients and may also revert to normal during IL-2/IFN alpha-based treatment. This alteration in NFkappaB activation occurred in the presence of normal expression of TCRzeta-associated signaling elements. The clinical significance of these findings remains unclear.

Phase I/II trial of all-trans retinoic acid and tamoxifen in patients with advanced breast cancer.

Because tamoxifen and all-trans-retinoic acid (ATRA) have additive antitumor effects in preclinical systems, we performed a Phase I/II clinical trial of this combination in patients with advanced breast cancer. Patients with potentially hormone-responsive advanced breast cancer were enrolled. All received 20 mg of tamoxifen by mouth daily. Consecutive cohorts of 3-6 patients were treated on odd-numbered weeks with ATRA at doses of 70, 110, 150, 190, or 230 mg/m2/day. Twenty-six patients were entered in this trial; 25 were evaluable. A dose of 230 mg/m2 ATRA produced unacceptable headache and dermatological toxicity, but doses < or = 190 mg/m2 were tolerable. Two of 7 patients with measurable disease responded. Seven of 18 patients with evaluable, nonmeasurable disease achieved disease stability for more than 6 months. Plasma AUCs on day 1 of successive weeks of treatment were stable over time. A nonsignificant decrease in serum insulin-like growth factor I levels was noted during treatment, but this trend was similar to that observed in three "control" patients treated with tamoxifen alone. When given with daily tamoxifen, the maximum tolerated dose of ATRA that could be given on alternate weeks was 190 mg/m2/day. This schedule of ATRA resulted in repeated periods of exposure to potentially therapeutic concentrations of ATRA. Declines in the serum insulin-like growth factor I concentrations observed in patients treated with tamoxifen and ATRA were similar to those observed in patients treated with tamoxifen alone. Objective responses were observed, some in patients who had previously progressed while receiving tamoxifen, suggesting that further studies would be of interest.

Phase II trial of circadian infusion floxuridine (FUDR) in hormone refractory metastatic prostate cancer.

Circadian administration of chemotherapy has been reported to decrease toxicity and possibly enhance efficacy. Between March 1991 and December 1993, 18 evaluable patients with progressive, hormone-refractory metastatic prostate cancer were treated in this phase II trial of circadian infusion floxuridine (FUDR). The drug was delivered through a central venous catheter using a CADD-Plus computerized pump such that approximately 70% of the drug was administered between 3 and 9 p.m. and the rest (30%) was administered between 9 p.m. and 3 p.m. The dose of FUDR was 0.15 mg/kg/day x 14 days every 4 weeks. A total of 79 complete cycles was administered. Two of 18 evaluable patients (11.1%) had decreases in PSA lasting five and eight months. No objective responses or improvement in bone scans was noted. The major toxicity observed was diarrhea. Although circadian infusion FUDR is feasible and tolerable, it has limited activity in hormone refractory prostate cancer.

Randomized trial of carboplatin plus amifostine versus carboplatin alone in patients with advanced solid tumors.

BACKGROUND: To test the hypothesis that the cytoprotectant amifostine attenuates the thrombocytopenia produced by carboplatin, the authors performed a randomized trial comparing treatment with carboplatin alone versus the combination of amifostine and carboplatin. METHODS: Patients with refractory or carboplatin-sensitive malignancies were randomized to receive either carboplatin, 500 mg/m2 alone or carboplatin, 500 mg/m2 in conjunction with 2 doses of amifostine of 910 mg/m2 each. RESULTS: Fifty-five patients with a variety of malignancies were entered on this study. One patient withdrew from each arm prior to the administration of any therapy, leaving 30 evaluable patients treated with carboplatin alone and 23 treated with the combination of amifostine and carboplatin. For 82 cycles of therapy with amifostine plus carboplatin, the median platelet nadir was 127 x 10(9)/L while the median platelet nadir was 88 x 10(9)/L over the 80 courses of therapy with carboplatin alone (P = 0.023). The median platelet nadir after the first cycle of therapy was 144 x 10(9)/L for patients treated with amifostine plus carboplatin and 85 x 10(9)/L for patients treated with carboplatin alone (P = 0.24). The median survival for 9 patients with advanced nonsmall cell lung carcinoma treated with carboplatin alone was 39 weeks whereas the median survival for 12 such patients treated with amifostine plus carboplatin was 52 weeks (P = 0.116). CONCLUSIONS: These data support the hypothesis that amifostine attenuates the myelosuppression of carboplatin. Additional studies of amifostine in combination with carboplatin-containing chemotherapy regimens are warranted.

Phase II trial of interleukin-2 and interferon-alpha in patients with renal cell carcinoma: clinical results and immunologic correlates of response.

A phase II trial was conducted in patients with metastatic renal cell carcinoma, to assess the clinical efficacy and immunoregulatory effects of continuous-infusion recombinant interleukin-2 (rIL-2) (9.0 x 10(6) IU/m2/day on days 1-5, 8-12, 15-19, and 22-26) and subcutaneously administered recombinant human interferon-alpha 2b (rHuIFN alpha 2b) (10.0 x 10(6) U/m2/day TIW). Thirty-six patients with metastatic renal cell carcinoma, performance status of 0-1, and measurable disease who had not received prior rIL-2, rHuIFN alpha 2b, or chemotherapy were treated. Patients with CNS metastases, active infections, history of another malignancy within 3 years, and those requiring corticosteroids were ineligible. Cycles of rIL-2 and rHuIFN alpha 2b were administered in the outpatient department every 6-8 weeks in stable or responding patients until patient tolerance or a complete response were reached. Doses were modified for grade III or IV toxicity. Ancillary studies included three-color immunocytometric analysis of peripheral blood lymphocytes, repetitive tumor biopsies for immunohistologic analysis of infiltrating cells and proliferative responses of tumor infiltrating lymphocytes, and preliminary studies of changes in peripheral blood T-lymphocyte signal transduction molecules [T-cell receptor (TCR)-zeta, p56ick, p59fyn]. Thirty-six eligible patients were treated, with 6 of 36 patients (17%, 95% confidence interval 6-33%) responding (3 complete response, 3 partial response). In two of the partial responders, and in an additional three patients with either minimal tumor regression (one patient) or stable disease (two patients), surgical removal of residual disease was undertaken. The median survival of all patients was 14 months. The toxicity of this regimen was severe, but outpatient administration was possible in most instances. Immunoregulatory effects on T-cell subsets included increases in various CD3+ CD25+/- HLADr+/- subsets unrelated to response. Tumor biopsies before and/or during therapy were obtained in 17 patients, and no consistent alterations in the degree of T-lymphocyte or macrophage infiltrates could be detected. In a subset of patients, tumor infiltrating lymphocyte proliferative responses and levels of peripheral blood T-cell signal transduction molecules (TCR-zeta, p56lck, p59fyn) were investigated. Abnormalities were found in selected patients, which improved during rIL-2/rHuIFN alpha 2b therapy. This cytokine combination produces tumor regression in selected patients with metastatic renal cell carcinoma. Surrogate immunologic markers associated with response were not identified; however, preliminary studies demonstrate investigation of immune defects and their reversal with cytokine therapy is possible.