Molecular biotherapy最新文献

We conducted a study to determine if treatment with cyclophosphamide (CY) could suppress the formation of anti-murine and anti-ricin A chain antibodies in rats treated with a murine monoclonal antibody-ricin A chain immunotoxin (IT). Female Sprague-Dawley rats received intravenous doses of IT at a dose of 5 mg/kg body weight alone or in combination with CY at a dose level of either 10 or 20 mg/kg body weight. The IT was given as one or two courses consisting of five consecutive daily intravenous injections (days 0 to 4, or days 0 to 4 and days 21 to 25 of the study). Cyclophosphamide was given on days 2, 4, 6, 13, and 17 of the study to the group receiving a single course of IT; additional doses of CY were administered on days 23, 25, and 27 to the group receiving two courses of IT. On days 4, 14, 21, 28, and 35, animals from each group were evaluated for antibodies to murine IgG and ricin A chain, and for clinical laboratory parameters and histopathology. Animals receiving IT alone developed significant titers of both anti-murine and anti-ricin A chain antibodies. Compared with the response in the animals receiving single-course IT, the response to both of the components of the IT was significantly increased on days 28 and 35 in the animals receiving a second course of IT. The groups receiving a combination of either one or two courses of CY and IT demonstrated a significantly decreased antibody response to both the murine IgG and the ricin A chain compared with the group receiving IT alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Recombinant human interferon alfa-2a (HuIFN alpha) was administered orally once daily in a low concentration (1,200 IU/day) to nine patients with chronic recurrent aphthous stomatitis (RAS), and a placebo solution was given to 10 control chronic RAS patients in a double-blind study. All HuIFN alpha-treated patients had total remission of their aphthae within a 2-week period, while placebo control patients had no change in their condition. The 10 placebo control patients were then treated with HuIFN alpha in a manner identical to that used for the initial principal group. Within a 2-week period, all original placebo patients had complete remission of their aphthae. Eleven of the patients did not have a recurrence of RAS during a subsequent 6-month observation period. Eight patients had recurring aphthae; however, the lesions were resolved by retreating with oral HuIFN alpha for less than 1 week.

Studies have suggested that recombinant tumor necrosis factor-alpha (TNF-alpha) may potentiate the killing of murine tumor cells by drugs targeted at DNA topoisomerase II. We have examined the combined cytotoxic effects of the topoisomerase-targeted drug etoposide and TNF in small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) cell lines using clonogenic assays and a novel flow cytometry technique relying on differential uptake of fluorescein diacetate (FDA) and propidium iodide (PI) by viable and nonviable cells. Good correlation of IC50 determinations for etoposide were noted between clonogenic assays and the FDA/PI technique for both classic and variant SCLC cell lines. The effects of etoposide on the classic SCLC line H209 were potentiated by TNF with a decrease in the IC50 from 3.3 microM to 1.0 microM as determined by FDA/PI. Tumor necrosis factor alone had little effect on the growth or cloning efficiency of H209 cells. Tumor necrosis factor alone stimulated the growth and cloning of variant SCLC line N417, but the cytotoxicity of etoposide was not potentiated by TNF in N417 cells. Tumor necrosis factor alone inhibited the growth and cloning of the NSCLC line H125 but exerted a marked protective effect against higher concentrations of etoposide. It appears that the interaction of TNF with etoposide varies between cell lines and between subclasses of human lung cancer.

Recombinant interferon alpha-C is a new strain of the alpha interferon family. It was given to 33 patients with measurable metastatic renal cell carcinoma of whom 31 were evaluable. Protocol consisted of 3 million U/d for 2 weeks, then 3 million U/m2 every other day until progression. No complete response was observed. Three patients (9.7%) had partial response for a mean duration of 5.6 months and eight patients (25.8%) were stabilized for a mean of 4.3 months. Responsive sites were mainly lung, bone, and kidney, while side effects were generally mild. better results were observed in previously nephrectomized patients who had not received chemotherapy or hormonotherapy for recurrent or metastatic disease (p less than 0.05), and also in patients with a brief disease-free interval and short delay from presenting symptoms of the primary tumor until interferon treatment (p less than 0.05). Median survival was significantly longer in responders than in progressors (p less than 0.05). We suggest that the efficacy of recombinant interferon alpha-C in a low-dose regime versus other types of interferon as first-line therapy for inoperable, metastatic, or locally recurrent renal cell carcinoma should be investigated in a prospective, controlled, randomized study.

The purpose of this study was to examine the effect of treatment with the biologic response modifier Pyrexol on murine host resistance to various infectious organisms. Adult female CD1 mice were treated with a single subcutaneous 100-micrograms injection of Pyrexol at 14, 7, 5, 2, or 1 day prior to infection with various infectious organisms. These organisms included the Herpes simplex type 2 and influenza viruses, as well as the bacteria Listeria monocytogenes and Streptococcus zooepidemicus. Pyrexol treatment was found to significantly potentiate resistance to Listeria organisms, but had no appreciable effect on resistance to any of the other organisms tested. Previous reports have demonstrated that treatment with Pyrexol augments a number of cell-mediated immune parameters, several of which have been shown to be responsible for the elimination of Listeria organisms. These results suggest that Pyrexol is capable of selectively potentiating host resistance to infection.

A phase II clinical trial was conducted using subcutaneous recombinant human interleukin-2 (rIL-2, EuroCetus) and subcutaneous interferon-alpha 2b (rIFN-alpha 2b, Essex) in patients with advanced cancer. Safety and tolerance of this outpatient regimen were assessed in 17 patients with progressive metastatic renal carcinoma, 14 of whom were evaluable for clinical response to combined rIL-2 and rIFN-alpha 2b. In this study, rIL-2 was administered every 12 hours, at 1.5 million (Cetus) U/m2 on days 1 and 2, followed by 0.3 million U/m2 5 days per week for 6 consecutive weeks. Concomitantly, rIFN-alpha 2b was given as 5 million U/m2 three times weekly for 6 consecutive weeks. Patients presenting with stable or regressive disease after 6 weeks of rIL-2 and rIFN-alpha 2b (11 of 14) were scheduled to repeat combination therapy. After one treatment cycle, five of 14 patients presented with partial remission; two of these patients achieved complete regression of metastatic lesions. After therapy, six patients have been in stable disease for up to 8 months. toxicity of this regimen was moderate, with local inflammation of the injection sites, grade I-II (World Health Organization criteria) fevers, chills, malaise, nausea and/or vomiting, and anorexia in 70% to 100% of patients treated. After 6 weeks of rIL-2 and rIFN-alpha 2b, laboratory evidence of treatment-related hypothyroidism and hyperthyroidism was obtained in one and four patients, respectively. Immunogenicity of sc rIL-2 was mostly limited to the development of nonneutralizing antibodies that occurred in approximately 40% of patients. None of the patients exhibited antibodies specific to rIFN-alpha 2b.

A preliminary study of the antitumor effect of partially purified human interferon alpha (IFN-alpha) and low-level direct current (DC) was carried out using a murine subcutaneous SA-1 experimental tumor model. Tumor-bearing animals were treated with 5 x 10(4) IU IFN-alpha peritumorally, or with 0.6 mA DC current for 15 minutes daily, for 6 consecutive days. Antitumor effect was manifested 2 days after the beginning of each treatment modality. Combined treatment with DC current applied immediately after IFN-alpha application was more effective than IFN-alpha treatment alone (P less than 0.005), but not significantly better than DC current treatment (P less than 0.5). The results indicate that the combined treatment with IFN-alpha and DC current can be effective in tumor therapy; however, further work is required to determine optimal scheduling.

In any formal statistical test of the null hypothesis (the statement that a population parameter is equal to a specific value), there are two possible types of error. Type 1 or alpha error has occurred if the investigator rejects the null hypothesis when it is true. For example, an experimental treatment is declared an advance over standard treatment when it is not. Type 2 or beta error has occurred if the null hypothesis is not rejected when it is false. In this case, the investigator concludes that the experimental treatment is no different than the standard when it actually is. The two types of error can be conceptualized, respectively, as the consumer's risk and the producer's risk. In many reports of clinical trial methodology, it is the producer's risk that is emphasized. It is understandable why producer's risk would be of concern to authors of clinical studies. There are, however, numerous potential sources of consumer's risk. It is the latter type of risk that is the primary subject of this report.