Enteral feeding in infants <1250 g starting within 24 h post-partum.

UNLABELLED: Establishing enteral feeding in the very low birth weight infant as soon as possible after birth has been shown to promote growth and reduce the need for intravenous lines. Human milk can be administered either as a continuous infusion or as intermittent boluses. The aim of this study was to investigate the effect of continuous versus bolus feeding on gastrointestinal tolerance, time to reach 120 ml/kg, 150 ml/kg and full enteral feeding, regain birth weight, duration of intravenous lines, incidence of septicaemia, persistent ductus arteriosus and necrotising enterocolitis. A retrospective analysis of hospital records was performed. Infants with a birth weight < 1250 g born during a 12-month period at Aker and Ullevål University hospitals in Oslo, who survived the first 21 days, were included in the study. A Total of 49 infants (25 continuous and 24 bolus) fulfilled the entry criteria and data from these infants were analysed. Enteral feeding volumes (120 ml/kg, 150 ml/kg and full) were attained significantly faster with continuous feeding (7 versus 12 days, 8 versus 14 days, 9 versus 12 days). Consequently the bolus group had a significantly longer duration of intravenous lines (14 versus 9 days). There were no differences regarding time to regain birth weight, the incidence of septicaemia, persistent ductus arteriosus or necrotising enterocolitis. CONCLUSION: infants of birth weight < 1250 g can be fed breast milk already from the 1st day of life and achieve full enteral feeds faster than previously reported even in more mature infants. Full enteral feeds are attained faster with continuous versus bolus feedings and continuous feeding therefore results in shorter need for intravenous fluids.

Influence of mild hypothermia after hypoxia-ischemia on the pharmacokinetics of gentamicin in newborn pigs.

The renal function is often affected in asphyxiated newborn infants. The pharmacokinetics of drugs like aminoglycosides eliminated through the kidneys may be impaired and require a different than usual dosage regimen. A decrease in body temperature is associated with a decrease in glomerular filtration rate and may, therefore, impair the elimination of aminoglycosides. When hypothermia is applied as neuronal rescue therapy after birth asphyxia, the pharmacokinetics of kidney-eliminated drugs may be impaired even more. We used our well-established global hypoxia-asphyxia newborn pig model to evaluate the effect of mild hypothermia after hypoxia-ischemia on gentamicin pharmacokinetics. Newborn pigs underwent global hypoxia-ischemia followed by normothermia (39 degrees C) for 72 h (n = 8) or mild hypothermia (35 degrees C) for 24 h followed by normothermia (39 degrees C) for 48 h (n = 8). Gentamicin pharmacokinetics was studied after three gentamicin doses: before hypoxia-ischemia, after hypoxia-ischemia during mild hypothermia or normothermia, and during normothermia 48 h after the first dose. The gentamicin pharmacokinetics variables were calculated using a SAAM II program. Hypoxia-ischemia altered renal function and gentamicin pharmacokinetics. The gentamicin clearance correlated with the creatinine plasma concentration (r = 0.89) and with the kidney pathology score (r = 0.55). There was no significant difference in gentamicin pharmacokinetics at 35 and 39 degrees C in newborn pigs after hypoxia-ischemia. The gentamicin pharmacokinetics variables were not different in the hypothermic or normothermic pigs after all three studied doses. Mild hypothermia for 24 h after hypoxia-ischemia does not affect gentamicin pharmacokinetics.

Interleukin-12 induced cytolytic activity in lymphocytes from recipients of autologous and allogeneic stem cell transplants.

Interleukin-12 (IL-12) has been reported to enhance the cytolytic activity of NK and activated T cells and to induce low levels of lymphokine-activated killer (LAK) activity in normal human lymphocytes. Therapy with IL-12 has induced tumor eradication in murine models. These observations suggest that IL-12 might have a role as treatment for minimal residual disease following transplantation. To determine whether PBL from recipients of autologous (autoSCT) and allogeneic (alloSCT) bone marrow or peripheral blood stem cell transplants respond to IL-12 with generation of LAK activity, PBL were incubated with IL-12 for 5 days, then tested in a 51Cr release assay for lysis of Daudi. PBL from 17 normal 'control' individuals were similarly tested and lysis was observed in only 3/17 (mean 16.9% of the three). By contrast, PBL from 10/12 patients obtained a median of 30 days after autoSCT, exhibited significant IL-12-induced LAK activity (mean lysis, 35.3%, P < 0.005 vs controls). PBL from 18 of 20 patients tested a median of 44 days after alloSCT also exhibited significant LAK activity (mean lysis, 30.0%, P < 0.005 vs controls). In autoSCT recipients, IL-12 and IL-2 at high concentrations (1000 U/ml each) were additive for induction of LAK activity, whereas low, suboptimal concentration of IL-12 (250 U/ml) and IL-2 (1 U/ml) were synergistic in 3/5 experiments. The percentage of PBL expressing IL-12 receptor beta 1 chain (IL-12r beta 1) was higher in stem cell recipients than in normal individuals, P < 0.05. Moreover, a higher percentage of IL-12r beta 1-positive PBL was associated with greater IL-12-induced LAK activity in transplant recipients. These studies demonstrate that PBL obtained early after stem cell transplantation have a higher percentage of cells expressing IL-12r beta 1 and respond to IL-12 with significantly greater LAK cytotoxicity than PBL from normal controls. These results suggest that IL-12 is a potentially attractive candidate for study as consolidative immunotherapy after stem cell transplantation.

Updated analysis of an outpatient chemoimmunotherapy regimen for treating metastatic melanoma.

PURPOSE: Aggressive inpatient chemoimmunotherapy protocols for metastatic melanoma have yielded encouraging response rates but have required lengthy hospitalizations. To reduce or eliminate the need for hospitalization, we have developed an outpatient chemoimmunotherapy regimen and assessed its efficacy and toxicity in 53 patients treated at the University of Washington Medical Center. PATIENTS AND METHODS: Eligible patients with measurable metastatic melanoma received carmustine (150 mg/m2 every 6-8 weeks) and dacarbazine (660 mg/m2) and cisplatin (75 mg/m2) every 3 to 4 weeks in an infusion center plus tamoxifen (20 mg/day). Patients self-administered subcutaneous recombinant interleukin-2 (rIL-2) at 3 MIU/m2/day on days 3 to 9, and recombinant interferon alfa-2a (rIFN-alpha 2a) at 3 MIU on day 3 and at 5 MIU/m2/day on days 5, 7, and 9. Maintenance rIFN-alpha 2a was self-administered subcutaneously at 5 MIU/m2 tiw for 12 months after complete or stable partial response. Response and survival were assessed. RESULTS: Fifty-three patients (median age = 49 years) have received 181 cycles. To date, there have been 10 complete responses (19%) lasting 2 to 28+ months and 12 partial responses (23%) lasting 2 to 11 months, for an overall response rate of 42% (95% confidence interval, 28%-55%). The median overall survival was 12 months. Grade 3/4 vomiting occurred in 32% of cycles, but hospitalization for supplemental intravenous fluids was required in only 11% of cycles for a median of 3 days. Grade 4 thrombocytopenia and neutropenia occurred in 9% and 8% of cycles, respectively. Grade 3 renal dysfunction occurred in only one cycle and was reversible. CONCLUSION: A chemoimmunotherapy regimen for patients with metastatic melanoma has been defined that is well tolerated on an outpatient basis and is associated with a median survival comparable to that with aggressive inpatient chemoimmunotherapy regimens.

Pentoxifylline inhibits integrin-mediated adherence of interleukin-2- activated human peripheral blood lymphocytes to human umbilical vein endothelial cells, matrix components, and cultured tumor cells.

Peripheral blood lymphocytes (PBLs) cultured in the presence of recombinant human interleukin-2 (rhIL-2) develop a natural killer (NK) cell phenotype (CD16+, CD56+, CD3-) and are referred to as lymphokine-activated killer cells (LAK). In developing the LAK phenotype, enhanced adherence to matrix components and endothelial cells have been described. In this report we investigated the functional behavior of adhesion receptors in rhIL-2-activated PBLs by in vitro adhesion assay and by flow cytometry. Compared to PBLs, IL-2-activated PBLs had increased integrin-mediated adherence to: (1) fibronectin (FN), (2) human umbilical vein endothelial (HUVE) cells, and (3) cultured melanoma and pancreatic tumor cell lines. This increase in adherence was mediated by increased surface expression of members of the beta 1 and beta 2 integrin subfamilies, as determined by flow cytometric analysis. No induction of an activation-dependent beta 1 (CD29) epitope was detected. We also investigated the effects of the methylxanthine derivative pentoxifylline (PTX) on PBLs and rhIL-2-activated PBL adhesion. PBLs co-cultivated in the presence of rhIL-2 (1,000 U/mL) and PTX exhibited reduced adherence to FN, HUVE and cultured tumor cell lines. This inhibition by PTX was concentration- and time-dependent. The increased expression of integrins induced by rhIL-2 was only in part inhibited by PTX, suggesting that PTX induced a subpopulation of integrins that are expressed but functionally inactive.

Lymphokine-activated killer (LAK) precursor cell activity is present in infused peripheral blood stem cells and in the blood after autologous peripheral blood stem cell transplantation.

Immunotherapy with interleukin-2 (IL-2) early after peripheral blood stem cell transplantation (PBSCT) is being considered as a potential way to eradicate minimal residual disease. The aim of this study was to determine whether lymphocytes which can acquire lymphokine-activated killer (LAK) cell activity are present in PBSC and in the blood of patients after PBSCT. Fresh and cryopreserved G-CSF-mobilized PBSC from eight patients were incubated with IL-2 (1000 U/ml) for 3-6 days and then tested for LAK activity as measured by lysis of the Daudi cell line. LAK activity was present in both fresh and cryopreserved PBSC, with mean lysis of 32% and 36%, respectively, at an effector:target (E:T) ratio of 50:1. To assess the reconstitution of LAK precursor activity after PBSCT, peripheral blood (PB) obtained from eight other patients 15-60 days after PBSCT was similarly tested. LAK activity was detected in PB from every patient (mean lysis of 38% at an E:T ratio of 12.5:1). PB from patients after PBSCT contained a higher percentage of CD8+ cells and CD56+ cells than did PB from 9 normal controls (47.2% vs. 21.4% CD8+ cells, P < 0.005 and 28.6% vs. 8.6% CD56+ cells, P < 0.0005). Moreover, PB from 4 of 5 patients tested after PBSCT exhibited a high percentage of cells expressing p75, the intermediate affinity IL-2R. Thus, precursor cells capable of acquiring IL-2-inducible LAK activity are present in PBSC and are rapidly reconstituted after PBSCT. The findings provide a rationale for testing IL-2 as a way of decreasing relapses after PBSCT.

Growth and autologous tumor lysis by tumor-infiltrating lymphocytes from metastatic melanoma expanded in interleukin-2 or interleukin-2 plus interleukin-4.

Optimal conditions for expanding tumor-infiltrating lymphocytes (TILs) specifically cytotoxic for autologous melanoma for clinical use have not yet been identified. In several small studies, interleukin (IL)-4 was reported to promote the growth of such TILs in IL-2. Given the potential implications for TIL therapy, we attempted to confirm these findings in a larger study. Baseline data were first obtained on the proliferation, immunophenotype, and cytotoxic reactivity to autologous melanoma of TILs cultured in IL-2 alone. Similar studies were performed with TIL cultured concurrently in either IL-2 alone or in a combination of IL-2 and IL-4. TILs were obtained by excisional biopsy of tumors from 52 patients with metastatic malignant melanoma; TILs from 38 patients were expanded in IL-2 (1,000 U/ml). TILs from 19 biopsies were maximally expanded 6- to 24,000-fold (median, 300-fold) over 4-10 weeks. Expansion did not correlate with the weight of, or number of lymphocytes in, the biopsy specimen, or the site of the biopsy (lymph node vs. subcutaneous metastases). During weeks 5-8, TILs from 19 of 25 biopsy specimens lysed autologous melanoma with little or no lysis of allogeneic melanoma. Lysis of autologous tumor was blocked by antibody to class I antigens. Twenty-four TIL specimens were cultured concurrently in IL-2 alone and in IL-2 plus IL-4 and tested for growth and for lysis of autologous and allogeneic melanomas.(ABSTRACT TRUNCATED AT 250 WORDS)

Induction by interleukin-7 of lymphokine-activated killer activity in lymphocytes from autologous and syngeneic marrow transplant recipients before and after systemic interleukin-2 therapy.

Therapy with recombinant lymphokines after autologous bone marrow transplantation (ABMT) is being explored as a way to prevent relapse. Lymphokine therapy may exert an antitumor effect through a variety of mechanisms, including the induction of lymphokine-activated killer (LAK) cell cytotoxicity. We tested the ability of interleukin-7 (IL-7) to induce LAK cytotoxicity in peripheral blood mononuclear cells (PBMC) from healthy subjects and from patients early after ABMT. LAK activity was defined as lysis of Daudi by PBMC after incubation with IL-7 at 10 to 100 ng/mL or IL-2 at 1000 U/mL. PBMC from four healthy subjects were cultured with either IL-7 or IL-2. IL-7 induced LAK activity in two of the four, whereas IL-2 induced LAK activity in all four. The median percent lysis (effector-to-target ratio [E:T] 40:1) with IL-7 (23%) was lower than with IL-2 (67%). PBMC were obtained from 15 patients 27 to 84 days after autologous (n = 13) or syngeneic (n = 2) bone marrow transplantation (BMT) and tested for IL-7-induced LAK activity. Eleven exhibited significant activity (10% to 77% lysis at E:T 40:1). In contrast to the results in PBMC from normal subjects, in PBMC from ABMT patients IL-7 induced LAK activity of a magnitude similar to that induced by IL-2. Studies were also performed on PBMC from eight patients who had received IL-2 after ABMT (3.0 x 10(6) U/m2/d) for 4 days by continuous intravenous (IV) infusion. In seven of the eight patients, IL-7 induced significant LAK activity, which was higher than that seen in PBMC from ABMT patients who had not received IL-2. Thus, IL-7 reproducibly induced significant LAK activity in cells obtained early after autologous or syngeneic BMT. Indeed, such LAK activity was comparable quantitatively to that induced by IL-2. Finally, IL-7 induced an even greater LAK activity in vitro in PBMC obtained after ABMT and preactivated in vivo by IL-2 therapy. The results suggest that IL-7 may have a potential immunotherapeutic role, alone or with IL-2, after ABMT.

The effects of pentoxifylline on the generation of human lymphokine-activated killer cell cytotoxicity.

Pentoxifylline (PTX) is a methylated xanthine that has been shown to reduce the toxicity of Interleukin-2 (IL-2) therapy in animal models, possibly by inhibiting secretion of tumor necrosis factor-alpha. However, the use of PTX to reduce IL-2 toxicity in cancer patients would be advantageous only if PTX did not abrogate antitumor effector mechanisms. We therefore tested the effects of PTX on the induction of lymphokine-activated killer (LAK) cell reactivity in human peripheral blood mononuclear cells (PBMCs). LAK precursor and effector activity were defined as lysis of Daudi cells by PBMCs after incubation with IL-2 at 1,000 U/ml (LAKp) or without incubation (LAKe). PBMCs from four healthy subjects were cocultured for 5 days with IL-2 and PTX (0-1.0 mM). LAKp was inhibited in a PTX dose-dependent manner, as the mean % lysis at an E:T ratio of 50:1 was 62, 43, and 8% in the presence of 0, 0.1, and 1.0 mM PTX, respectively. To determine the effect of in vivo PTX on LAKp activity, four healthy subjects were tested after treatment with PTX at 2 g/day for 3 days. LAKp activity was detected in all four and was not inhibited by autologous serum containing PTX and biologically active metabolites. Because lymphocytes "preactivated" by IL-2 in vivo may respond to PTX differently than resting cells, two patients were tested after a 5 day infusion of IL-2 at 6 x 10(6) U/m2/day. PBMCs from both displayed LAKp activity, with far less inhibition by PTX than in resting cells (4, 17, and 37% inhibition at 0.05, 0.1, and 1.0 mM, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Prolonged continuous intravenous infusion interleukin-2 and lymphokine-activated killer-cell therapy for metastatic renal cell carcinoma.

PURPOSE: Two consecutive protocols of continuous intravenous (CIV) infusion interleukin-2 (IL-2) and lymphokine-activated killer (LAK) cells were carried out in patients with metastatic renal cell carcinoma (RCC) to determine the response rate and toxicity. PATIENTS AND METHODS: In both protocols, patients received induction IL-2 at 6 x 10(6) U/m2/d on days 1 to 5, and underwent leukapheresis on days 7 to 9 at the peak of rebound lymphocytosis. LAK cells were generated by a 5-day incubation with IL-2 at 1,000 U/mL, and were infused on days 12 to 14. For the first 20 patients (protocol A), maintenance IL-2 was administered at 6 x 10(6) U/m2/d on days 12 to 16. On the assumption that less IL-2 might be required to maintain rather than to induce LAK activity, and that a longer duration of maintenance IL-2 might enhance LAK survival and function in vivo, the protocol for the subsequent 22 patients (protocol B) was altered so that the maintenance phase consisted of a lower dose of IL-2 (2 x 10(6) U/m2/d) administered for a longer period of time (days 10 to 20). RESULTS: In protocol A, there were two complete responses (CRs) and three partial responses (PRs), for a total response rate of 25%. One PR was surgically converted into a CR. The durations of the CRs are 36+, 18+, and 18+ months. Hypotension and capillary leak were most severe during maintenance, which limited the median duration of maintenance IL-2 to 4 days. In protocol B, no patient experienced severe hypotension, and the median duration of maintenance IL-2 was 9 days. Two patients exhibited a CR and seven a PR, for a total response rate of 41%. Two PRs were surgically converted to CRs. The durations of CR are 14+, 9+, 6+, and 5+ months. In both protocols, the CIV induction regimen resulted in marked rebound lymphocytosis (mean, 11,097/microL) and LAK-cell yield (mean, 18.1 x 10(10)). The cumulative response rate was 14 of 42 patients, or 33% (95% confidence interval, 19% to 47%). CONCLUSION: These results demonstrate that both protocols of CIV IL-2 plus LAK cells have substantial antitumor activity, and that a longer maintenance phase of IL-2 at a lower dose is associated with significantly less toxicity without a loss of therapeutic efficacy.

Enhancement by interleukin 4 of interleukin 2- or antibody-induced proliferation of lymphocytes from interleukin 2-treated cancer patients.

Systemic interleukin 2 (IL-2) and IL-2-activated lymphocytes have induced tumor regression in some cancer patients. The IL-2-activated cells have usually been generated by obtaining peripheral blood mononuclear cells (PBMC) from cancer patients shortly after systemic IL-2 therapy and culturing them with IL-2 in vitro. In an effort to augment the ex vivo generation of such cells preactivated in vivo, we examined the proliferative responses of PBMC from IL-2-treated cancer patients to several proliferative signals including IL-2, interleukin 4 (IL-4), and mitogenic antibodies to CD3 and CD28. Although much is known about the response of normal PBMC to these signals, the possibility was considered that the response of lymphocytes preactivated by IL-2 in vivo might differ from that of normal PBMC. Accordingly, PBMC obtained from ten normal, healthy controls and from 17 patients with advanced cancer 1 to 3 days after systemic IL-2 therapy were cultured for 4 days with IL-4 (1000 units/ml) and/or IL-2 (10 units/ml or 1000 units/ml) or with combinations of IL-4 and anti-CD3 +/- anti-CD28, and they were then tested for proliferation by [3H]thymidine incorporation. IL-4 failed to induce proliferation of normal PBMC and inhibited IL-2-induced proliferation, whereas IL-4 alone induced proliferation in PBMC from five of 11 IL-2-treated patients and did not inhibit but augmented the proliferation induced by IL-2 (10 units/ml and 1000 units/ml) in PBMC from six of nine patients and five of 11 patients, respectively. Anti-CD3 induced proliferation in PBMC from eight of nine patients, and the proliferation was consistently augmented by coculture with anti-CD28. Finally, IL-4 significantly augmented the proliferative responses of PBMC from IL-2-treated patients to anti-CD3, as well as to the combination of anti-CD3 and anti-CD28. Thus, in PBMC from IL-2-treated cancer patients, IL-4 enhanced the in vitro proliferation induced by IL-2 or by anti-CD3 +/- anti-CD28. The results suggest that IL-4 and/or mitogenic antibodies may be useful in augmenting the ex vivo generation of lymphocytes for clinical adoptive immunotherapy.

Induction of lymphokine-activated killer activity by interleukin 4 in human lymphocytes preactivated by interleukin 2 in vivo or in vitro.

In an attempt to augment the generation of human cytotoxic effector cells for potential cancer therapy with interleukin 2 (IL2) and lymphokine-activated killer (LAK) cells, the effect of interleukin 4 (IL4) on LAK cell induction was studied. In normal human peripheral blood lymphocytes (PBL), IL4 does not induce LAK activity and inhibits LAK induction by IL2. However, since lymphocyte activation, such as with antigen or mitogen, can render them responsive to IL4, the ability of IL4 to induce LAK activity in lymphocytes preactivated in vivo or in vitro with IL2 was investigated. PBL obtained from 12 patients with advanced cancer 1 to 3 days after IL2 therapy and from eight healthy control subjects were cultured 4 to 5 days with or without IL4 and/or IL2 and then tested for LAK activity as assessed by lysis of Daudi in a 4-h 51Cr release assay. In normal PBL, IL4 failed to induce LAK activity and consistently inhibited LAK induction by a suboptimal concentration of IL2 (10 units/ml). By contrast, IL4 induced LAK activity in PBL from seven of twelve IL2-treated patients and augmented LAK induction by the suboptimal IL2 in PBL from five of twelve IL2-treated patients. With an optimal LAK-inducing concentration of IL2 (1000 units/ml), IL4 less consistently inhibited LAK induction in normal PBL and had a variable effect upon LAK induction in PBL from IL2-treated patients. IL4 induced LAK activity in PBL obtained from a cancer patient after, but not before, systemic IL2 therapy. Similarly, IL4 induced LAK activity in normal PBL only after they had been preincubated with IL2. Thus, IL4 induces LAK activity in lymphocytes preactivated by IL2 in vivo or in vitro. Fluorescence-activated cell sorting revealed that the LAK activity, whether induced by IL4 or by IL2, was mediated largely by non-T (CD5-) natural killer-like (CD56+) cells. The results suggest a regulatory relationship between IL2 and IL4 in the induction and/or maintenance of LAK activity, which might be exploited to augment the generation of cytotoxic cells for lymphokine-mediated immunotherapy of human cancer.

Lymphokine-activated killer function following autologous bone marrow transplantation for refractory hematological malignancies.

Disease recurrence remains the major factor which limits the success of autologous bone marrow transplantation (ABMT) for refractory hematological malignancies. The administration of interleukin 2 (IL2) with or without ex vivo generated lymphokine-activated killer (LAK) cells represents a potential approach to eradicating residual disease after ABMT. However, since LAK precursor activity is radiosensitive, high dose chemoradiotherapy may abrogate LAK function and preclude clinical responsiveness to IL2 after ABMT. Furthermore, since lymphocyte subsets which mediate LAK activity may recover at different rates after ABMT, LAK cells may be phenotypically and/or functionally altered after ABMT. To determine whether IL2 responsive LAK precursor cells are present in the circulation after ABMT, peripheral blood mononuclear cells (PBMC) from 21 patients with acute leukemia or lymphoma were tested for IL2-inducible LAK activity 17-83 days after ABMT. Cells were cultured with IL2 (1000-2000 units/ml) for 4 or 5 days and then tested for cytolytic activity and/or cell phenotype. LAK activity against the Daudi cell line was detected in every PBMC sample from every patient at every time point tested. The Raji cell line and a fresh allogeneic ovarian carcinoma were also lysed by LAK cells generated after ABMT. In the subgroup of patients transplanted for non-Hodgkin's lymphoma, LAK precursor activity appeared comparable to that of healthy controls. Culture with IL2 resulted in increased mean IL2 receptor expression in lymphocytes from patients after ABMT (3.1-9.9%) and from healthy controls (3.1-12.0%). After culture with IL2, the percentage of cells bearing the natural killer cell-associated Leu-19 determinant was significantly higher in patient PBMC than in normal control PBMC (28.3 versus 8.7%). Positive and negative cell selection by fluorescence sorting after culture with IL2 revealed that most of the LAK activity after ABMT was mediated by the Leu-19+ cells. Although CD5+ T-cells were devoid of LAK activity, a subset LAK effectors was CD8+. Thus, LAK activity is rapidly reconstituted after ABMT and is mediated by cells phenotypically similar to those in normal controls. These results support the feasibility of IL2 +/- LAK as consolidative immunotherapy after ABMT.

Influence of schedule of interleukin 2 administration on therapy with interleukin 2 and lymphokine activated killer cells.

The purpose of this study was to compare the toxicity, immunomodulatory changes, and antitumor efficacy of interleukin 2 (IL-2) and lymphokine activated killer (LAK) cell therapy with two durations of IL-2 infusion. Patients with progressive melanoma, non-Hodgkin's lymphoma, renal carcinoma, or colon carcinoma received IL-2 at 3 X 10(6) units/m2/day on days 1-5 and 13-17, either by bolus injection every 8 h (q8h) or by continuous i.v. (CIV) administration. Peripheral blood mononuclear cells were harvested by leukapheresis on days 8, 9, and 10, were incubated in vitro for 5 days for generation of LAK cells, and were infused on days 13, 14, and 15. The first 11 patients were treated with IL-2 q8h, and the subsequent 13 patients were treated by CIV infusion. Toxicity consisted primarily of fever, chills, emesis, diarrhea, weight gain, and edema but did not require intensive care unit support and did not differ significantly between treatment groups. IL-2-induced lymphocytosis on day 8 was higher with CIV than with q8h administration with a mean lymphocyte count/microliter of 5610 +/- 700 (SE) versus 3300 +/- 500. Immunomodulatory changes observed on days 8 and 20 were also greater with CIV IL-2 and included an increase in peripheral blood mononuclear cell IL-2 receptor expression as well as a marked rise in the number of Leu-11+ and Leu-19+ peripheral blood mononuclear cells. The total leukapheresis yield per patient and total number of LAK cells infused per patient were higher with CIV than q8h administration, with 49.8 +/- 4.9 X 10(9) versus 39.4 +/- 5.4 X 10(9) and 42.6 +/- 5.0 X 10(9) versus 34.0 +/- 5.4 X 10(9), respectively. The cells infused displayed phenotypic evidence of activation and exhibited marked lytic reactivity to Daudi, Raji, and HT-144 targets. One complete and one minimal response were observed in 2 of 8 patients with metastatic renal cell carcinoma who received CIV IL-2 and LAK cells. The results show that IL-2 is more biologically active by CIV than q8h administration, as demonstrated by greater rebound lymphocytosis, LAK cell yield, and in vivo immunostimulation.

Influence of dose and duration of infusion of interleukin-2 on toxicity and immunomodulation.

The purpose of this study was to investigate the effect of dose and duration of infusion of recombinant interleukin-2 (IL-2) on toxicity and immunomodulation. In a phase I/II study, IL-2 was administered intravenously (IV) daily for five consecutive days every other week for 4 weeks of treatment to 23 patients with progressive melanoma, renal, colon, or ovarian cancer by one of four regimens: groups I and II received 3 X 10(5) U/m2/d by two-hour or 24-hour infusion, respectively; groups III and IV received 3 X 10(6) U/m2/d by two-hour or 24-hour infusion, respectively. In a subsequent study, six patients (group V) received a single priming cycle of daily IL-2 for five days at 3 X 10(6) U/m2/d in divided 15-minute infusions every eight hours, before undergoing leukapheresis for lymphokine-activated killer (LAK) cell generation. Toxicity was mild with 3 X 10(5) U/m2/d, but severe chills and fever, moderate hypotension (not requiring IV pressors), and weight gain were observed with 3 X 10(6) U/m2/d. Toxicity was also related to the duration of infusion. In group IV (continuous infusion), fluid retention, weight gain, and azotemia were more frequent and severe than in groups III or V, in which the same total dose was administered by two-hour infusion or in three divided 15-minute infusions. IL-2 induced rebound lymphocytosis, which was directly dose-related and significantly higher in group IV (continuous infusion) than in groups III or V. Dramatic increases in the percentage and absolute number of cells expressing the IL-2 receptor were also most pronounced in group IV. With the higher dose of IL-2, LAK cells appeared in the circulation, and natural killer (NK) cytotoxicity was augmented. The results showed that the toxicity and immunomodulation by IL-2 are dose-dependent and are maximal by continuous infusion compared with two-hour or divided every eight hours infusions.

Impaired in vivo and in vitro antibody responses to bacteriophage phi X 174 in juvenile rheumatoid arthritis.

Immunologic abnormalities described in juvenile rheumatoid arthritis (JRA) have been largely confined to mitogen or antigen driven proliferation assays. We studied antigen specific antibody production using the neoantigen bacteriophage phi X 174 in vivo and in vitro; defective responses were found in all 8 patients with JRA studied. These could not be attributed to circulating anti-T cell antibodies, but may relate to lymphocyte subset abnormalities found by 2 color analyses. These immunologic aberrations may play a direct role in the pathogenesis of JRA or, alternatively, may be a secondary event.

Recombinant interleukin 2 toxicity, pharmacokinetics, and immunomodulatory effects in a phase I trial.

Twenty-two patients with refractory malignancies were treated with four escalating weekly doses of recombinant interleukin 2 (IL2), given either i.v. by 2- or 24-h infusion, or s.c. A 1-wk washout period between each dose of IL2 was provided for the evaluation for pharmacokinetic and immunomodulatory effects. The maximum i.v. dose was 30 X 10(6) units; the dose-limiting toxicities were fever, flu-like symptoms, and hypotension. The maximum s.c. dose was 3 X 10(6) because of volume limitations with s.c. injection. No tumor regression was seen. During infusions of 3 X 10(6) units over 2 h or 24 h, serum IL2 levels greater than or equal to 223 units/ml or 16 units/ml were maintained, respectively; with s.c. injection of 3 X 10(6) units, levels greater than 20 units/ml were maintained for 9 h. Marked lymphopenia was observed 24 h after the initiation of IL2 doses which was completely reversible when measured prior to the next dose. The lymphopenia was nonselective; T- and B-lymphocytes decreased in an IL2 dose-dependent manner, without consistent change in the OKT4:OKT8 ratio. No change was detected in monocyte expression of HLA-Dr or T-cell expression of the IL2 receptor. The in vitro generation of lymphokine-activated killer cytotoxicity decreased sharply and transiently shortly after i.v. doses. Mitogen responsiveness, delayed-type hypersensitivity, natural killer cytotoxicity, and mixed-lymphocyte reactivity were unchanged or decreased transiently shortly after IL2 doses. These studies help define the bioavailability of IL2 by i.v. or s.c. routes, and they will aid in the design of studies utilizing daily doses of IL2.

Subcutaneous recombinant gamma interferon in cancer patients: toxicity, pharmacokinetics, and immunomodulatory effects.

Recombinant gamma interferon (r gamma-IFN) was administered s.c. daily to 26 patients with advanced cancer. Patients were assigned to one of six doses: 0.5, 1, 2, 4, 6, or 8 million units (MU)/m2 per d. The major toxicities were an influenza-like syndrome and fever, seen in all patients. Dose limiting toxicity occurred in 4 of 4 patients treated at 8 MU/m2. One patient with nodular poorly differentiated lymphocytic lymphoma had a mixed response, and two patients with renal cell cancer have had stabilization of disease for greater than 10 and greater than 12 months. Pharmacokinetic analysis, by radioimmunoassay, revealed mean serum r gamma-IFN concentrations up to 17 ng/ml, with maximal serum levels noted 6 to 13 h after injection. In vivo immunomodulation was assessed by natural killer (NK) cytotoxicity, monocyte activation as determined by cell surface expression of HLA-Dr, and peripheral blood mononuclear cell phenotype analysis by flow cytometry. The mean T4/T8 ratio increased from 2.1 pretreatment to 4.1 after 24 h of treatment, but returned to baseline after 7 and 28 days of treatment. Augmentation of NK function was noted after 7 days of treatment. Monocyte cell surface expression of HLA-Dr increased after 28 days of treatment at the three lowest doses. In conclusion, daily s.c. r gamma-IFN can be easily administered on an outpatient basis with minimal local skin toxicity, results in prolonged serum levels, and is associated with immunological changes of potential antitumor significance. Further study of the in vivo immunomodulatory effects induced by r gamma-IFN is indicated to help define the optimal treatment regimen.