Clinical evaluation of adenoviral-mediated p53 gene transfer: review of INGN 201 studies

Gene therapy represents a new modality of cancer therapeutics based on novel mechanisms of action. Modified adenoviruses have important properties that lend themselves readily to commercial-scale manufacturing; with an excellent safety record, they have been used as the gene transfer vector in most clinical studies to date. They provide a potent means of delivering genes into cancer cells. Although multiple genes are involved in the development of malignancy, preclinical models (and now clinical studies) have proven that insertion of a single gene, p53, can arrest cancer cell growth and induce apoptosis and tumor regression in advanced cancers such as squamous cell cancer of the head and neck and non-small cell lung cancer. With equally strong rationale, clinical studies using combination approaches also have been initiated, with promising results in localized inoperable non-small cell lung cancer. In addition, the apparent safety, and especially the lack of adverse effects on normal tissues at injection sites following gene transfer, have stimulated an evaluation of intervention in the postoperative surgical adjuvant setting and in treating premalignancies. The goal of these studies has been to provide an antitumor locoregional effect. This may result in effective palliation in the advanced-disease setting, especially for diseases that do not metastasize widely. However, the most exciting near-term potential of p53 gene transfer using INGN 201 will be in up-front regimens in combination with surgery, radiation, and chemotherapy in the many clinical settings where local disease control remains suboptimal.

Cellular and humoral immune responses to adenovirus and p53 protein antigens in patients following intratumoral injection of an adenovirus vector expressing wild-type. P53 (Ad-p53)

The immune responses of 10 patients with advanced non-small cell lung cancer receiving monthly intratumoral injections of a recombinant adenovirus containing human wild-type p53 (Ad-p53) to adenovirus and transgene antigens were studied. The predominate cellular and humoral immune responses as measured by lymphocyte proliferation and neutralizing antibody (Ab) formation were to adenovirus serotype 5 vector antigens, with increased responses in posttreatment samples. Consistent alterations in posttreatment cellular and humoral immune responses to p53 epitopes were not observed, and cytotoxic Abs to human lung cancer cells were not generated. Patients in this study had evidence of an antitumoral effect of this treatment with prolonged tumor stability or regression; however, neither Abs to p53 protein nor increased lymphocyte proliferative responses to wild-type or mutant p53 peptides have been consistently detected.

Pericranial flap correction of superior sulcus depression in the anophthalmic orbit

Distortion of the supratarsal sulcus of the upper eyelid after orbital trauma is a well-recognized and troublesome problem. This is particularly true of the anophthalmic orbit. The authors present two patients in whom this deformity has been addressed using a pedicled pericranial flap. They found this technique provides abundant, well-vascularized tissue that is manipulated easily to conform to the demands of the defect. In addition, the vascularity of the tissue provides predictability of the result when compared with other described techniques such as fat and dermis-fat grafts.

Bivariate analysis of the p53 pathway to evaluate Ad-p53 gene therapy efficacy

BACKGROUND

Gene therapy of human tumors with adenovirus vectors presents a clinical research challenge and a potential opportunity in cancer therapy. One of the research challenges is that endpoints like tumor reduction, time to recurrence, and survival do not provide information about whether a potential therapeutic infects the targeted cells or whether the transferred gene functions or induces a cellular response. Therefore, a flow cytometric approach was developed for a wildtype, p53 encoding adenoviral vector (Ad-p53) that provides (1) the relative level of p53 transferred by p53 immunoreactivity, (2) mdm2 immunoreactivity as an assay of p53 activity, and (3) estimates of the percentage of infected cells by dual parameter analysis (p53 versus mdm2).

METHODS

Three prostate cancer cell lines (PC-3, LNCaP, DU 145) that are null, wild-type, and mutant for p53, respectively, and two ovarian cancer cell lines (PA1, MDAH 2774) that are wild-type and mutant for p53, respectively, were tested for immunoreactivity and lack of cross-reactivity with the monoclonal antibodies, DO-7 (anti-p53) and IF2 (anti-mdm2). Optimal dual staining conditions for a flow cytometric assay employing saturating levels of antibody were developed and tested by infection of PC-3, PA1, and MDAH 2774 with Ad-p53 or a control virus, Ad-luc. Dual staining with DO-7 and propidium iodide was used to determine any biological effect of the transferred gene.

RESULTS

Neither DO-7 nor IF2 showed appreciable cross-reactions by Western blot analysis of representative prostate or ovarian cell lines. By flow cytometric titration, DO-7 appears to be a high avidity antibody (saturation staining of 10(6) DU 145 cells with 0.5ug) whereas IF2 appears less so (optimum signal to noise ratio at 1ug/10(6) cells). Infection with Ad-p53 was detected at 6 to 48 hours post infection as a uniform relative increase in p53 levels over background p53 levels. Coincident increases in mdm2 immunoreactivity were also detected. DNA content measurements of PA1 and MDAH 2774 cells indicated that G1 arrest and/or apoptosis occurred subsequent to Ad-p53 infection. p53 and mdm2 levels and DNA content distributions for Ad-luc infected cells were equivalent to uninfected cells.

CONCLUSIONS

A flow cytometric approach to measure the efficacy of an Ad-p53 gene therapy vector was developed that detects not only the gene transferred but also the activity of the transferred gene product.

Adenovirus-mediated p53 gene transfer in advanced non-small-cell lung cancer

BACKGROUND

Preclinical studies in animal models have demonstrated tumor regression following intratumoral administration of an adenovirus vector containing wild-type p53 complementary DNA (Ad-p53). Therefore, in a phase I clinical trial, we administered Ad-p53 to 28 patients with non-small-cell lung cancer (NSCLC) whose cancers had progressed on conventional treatments.

METHODS

Patients received up to six, monthly intratumoral injections of Ad-p53 by use of computed tomography-guided percutaneous fine-needle injection (23 patients) or bronchoscopy (five patients). The doses ranged from 10(6) plaque-forming units (PFU) to 10(11) PFU.

RESULTS

Polymerase chain reaction (PCR) analysis showed the presence of adenovirus vector DNA in 18 (86%) of 21 patients with evaluable posttreatment biopsy specimens; vector-specific p53 messenger RNA was detected by means of reverse transcription-PCR analysis in 12 (46%) of 26 patients. Apoptosis (programmed cell death) was demonstrated by increased terminal deoxynucleotide transferase-mediated biotin uridine triphosphate nick-end labeling (TUNEL) staining in posttreatment biopsy specimens from 11 patients. Vector-related toxicity was minimal (National Cancer Institute's Common Toxicity Criteria: grade 3 = one patient; grade 4 = no patients) in 84 courses of treatment, despite repeated injections (up to six) in 23 patients. Therapeutic activity in 25 evaluable patients included partial responses in two patients (8%) and disease stabilization (range, 2-14 months) in 16 patients (64%); the remaining seven patients (28%) exhibited disease progression.

CONCLUSIONS

Repeated intratumoral injections of Ad-p53 appear to be well tolerated, result in transgene expression of wild-type p53, and seem to mediate antitumor activity in a subset of patients with advanced NSCLC.

Gene therapy for non-small cell lung cancer: a preliminary report of a phase I trial of adenoviral p53 gene replacement

The identification of genetic lesions that lead a normal cell to become malignant presents us with the opportunity of targeting those lesions as a means of therapy. Given the key role played by the tumor suppressor gene p53 in cell cycle regulation and apoptosis, and the evidence linking p53 mutations with non-small cell lung cancer, attempts at p53 replacement are a logical approach to therapy in this disease. In a phase I study, administration of an adenoviral p53 vector (Adp53) to 21 patients with advanced non-small cell lung cancer produced little toxicity. Up to six intratumoral injections at monthly intervals were well-tolerated. Expression of the p53 transgene was evident, along with potentially useful clinical responses. Time to disease progression in the indicator lesion treated with Adp53 appears to be enhanced by higher doses of vector, concomitant cisplatin therapy, and evidence of apoptosis on tumor biopsy specimens. Phase II trials should now be undertaken to determine the response rate to Adp53.

Adenovirus-mediated p53 gene transfer in patients with advanced recurrent head and neck squamous cell carcinoma

PURPOSE

Standard therapies of head and neck squamous cell carcinoma (HNSCC) often cause profound morbidity and have not significantly improved survival over the last 30 years. Preclinical studies showed that adenoviral vector delivery of the wild-type p53 gene reduced tumor growth in mouse xenograft models. Our purpose was to ascertain the safety and therapeutic potential of adenoviral (Ad)-p53 in advanced HNSCC.

PATIENTS AND METHODS

Patients with incurable recurrent local or regionally metastatic HNSCC received multiple intratumoral injections of Ad-p53, either with or without tumor resection. Patients were monitored for adverse events and antiadenoviral antibodies, tumors were monitored for response and p53 expression, and body fluids were analyzed for Ad-p53.

RESULTS

Tumors of 33 patients were injected with doses of up to 1 x 10(11) plaque-forming units (pfu). No dose-limiting toxicity or serious adverse events were noted. p53 expression was detected in tumor biopsies despite antibody responses after Ad-p53 injections. Clinical efficacy could be evaluated in 17 patients with nonresectable tumors: two patients showed objective tumor regressions of greater than 50%, six patients showed stable disease for up to 3.5 months, and nine patients showed progressive disease. One resectable patient was considered a complete pathologic response. Ad-p53 was detected in blood and urine in a dose-dependent fashion, and in sputum.

CONCLUSION

Patients were safely injected intratumorally with Ad-p53. Objective antitumor activity was detected in several patients. The infectious Ad-p53 in body fluids was asymptomatic, and suggests that systemic or regional treatment may be tolerable. These results suggest the further investigation of Ad-p53 as a therapeutic agent for patients with HNSCC.

Active specific immunotherapy of metastatic melanoma with an antiidiotype vaccine: a phase I/II trial of I-Mel-2 plus SAF-m

PURPOSE

To determine the toxicity and immunologic activity of an antiidiotype melanoma vaccine that consists of monoclonal antibody I-Mel-2 (MELIMMUNE-2, IDEC Pharmaceuticals, La Jolla, CA) and an immunologic adjuvant SAF-m.

PATIENTS AND METHODS

Twenty-six patients with metastatic melanoma, 17 of whom had previously received chemotherapy, were given 2 mg of I-Mel-2 and either 100 micrograms (n = 6) or 250 micrograms (n = 20) of SAF-m. Antiidiotype vaccine was given intramuscularly (IM) biweekly for 4 weeks, and then bimonthly until disease progression. Human antimurine antibodies (HAMA), anti-I-Mel-2 antibodies, and specific antibody (Ab)3 against the melanoma epitope mimicked by the vaccine were titrated before treatment, biweekly from weeks 4 to 12, and every 4 to 8 weeks thereafter. Computed tomographic (CT) scans of the chest, abdomen, and pelvis and magnetic resonance imaging (MRI) of the brain were obtained before and bimonthly during treatment to evaluate responses.

RESULTS

Elevated titers of human antimouse antibodies and anti-I-Mel-2 antibodies were associated with clinical antitumor effect (P = .02 and P = .05, respectively). Ab3 was absent in most patients, but was found in the best clinical responder. Fever, myalgias/arthralgias, fatigue, nausea, and headaches were the most common toxicities. Grade III myalgias/arthralgias and headaches required dose reduction of SAF-m in eight patients at the 250-microgram dose. No treatment-related death occurred. Six patients had an antitumor effect: one complete response in liver and lung, two minor responses, and three stable disease. The patient with a complete response has survived nearly 5 years.

CONCLUSION

I-Mel-2 antiidiotype vaccine was safe, tolerated best at the 100-microgram dose of SAF-m, and had immunologic and clinical activity.

Adult perception of emotion intensity in human infant cries: effects of infant age and cry acoustics

The relation between adult perception of emotion intensity in the cries of 1- and 6-month-old infants and the acoustic characteristics of the cries was examined. In the first study, adults who were inexperienced in child care rated 40 cries on 3 emotion intensity scales: anger, fear, and distress. The cries of 6-month-olds were rated as being significantly more intense. Different acoustic variables accounted for emotion intensity ratings for the 2 infant ages. Peak amplitude and noisiness of the cry predicted adult judgments of intensity ratings of 1-month-olds' cries; a measure of amplitude ratio (in 2 frequency bands) was the best predictor of intensity ratings of 6-month-olds' cries. In the second study, parents of infants rated the same cries on the same scales. They also rated the older infants' cries as being more intense. The 2 adult groups did not differ on their ratings, and a regression equation derived from one adult group predicted the other adult group's rating of the same infant age better than it predicted its own ratings for the other infant age. Infant age, and its associated acoustic features, seems to be a more important determinant of adults' perception of emotion intensity than are such adult characteristics as gender or infant-care experience.

Modulation of 2',5'-oligoadenylate synthetase in patients treated with alpha-interferon: effects of dose, schedule, and route of administration

The interferon (IFN)-induced intracellular enzyme 2',5'-oligoadenylate (2-5A) synthetase was measured in extracts of peripheral mononuclear cells isolated from patients receiving a 300-fold range of doses of alpha interferon (IFN-alpha). The range of enzyme induction was 2.3- to 5.7-fold. The maximum fold increase varied from individual to individual as did the dose required for maximum enzyme stimulation. The magnitude and endurance of the enzyme response was a function of IFN dose and was unrelated to the duration of treatment or number of injections or to the route of administration. The enzyme assay was a more sensitive indicator of IFN administration than was measurement of the level of circulating IFN. These results substantiate the potential of a clinical 2-5A synthetase assay for monitoring IFN treatment.

Phase 1 trial of oral bropirimine in superficial bladder cancer

A total of 34 patients with measurable superficial transitional cell cancer of the bladder entered into a phase 1, nonrandomized, noncomparative trial to assess the toxicity of the oral interferon inducer bropirimine. Of the patients 26 were also evaluable for response. The toxicity of bropirimine was minimal. At the 3-month evaluation 6 patients had experienced complete regression of tumor and had negative cytology studies, and 2 had partial responses. The majority of complete responses were in patients with carcinoma in situ only, with most responses seen at higher dose levels. One patient with papillary tumor and carcinoma in situ had a complete response. Some early responses appear to be durable. Most importantly, a high rate of complete response was noted at higher dose levels among patients who had failed prior therapy with bacillus Calmette-Guerin. Further clinical trials of bropirimine in bladder cancer appear warranted.

Soluble CD4-PE40 is cytotoxic for a transfected mammalian cell line stably expressing the envelope protein of human immunodeficiency virus (HIV-1), and cytotoxicity is variably inhibited by the sera of HIV-1-infected patients

Sera were obtained from 50 individuals infected with human immunodeficiency virus type 1 or from HIV-1-uninfected individuals before or after vaccination with recombinant gp160. These sera were evaluated for activity antagonistic to the cell-killing activity of the chimeric Pseudomonas exotoxin hybrid protein, sCD4-PE40. For these studies, Chinese hamster ovary (CHO) cells were transfected with a chimeric plasmid encoding the tat, rev, and envelope genes of HIV-1 and a cell line was selected for stable expression of the envelope glycoproteins at the cell surface (CHO-env). Cytotoxicity of sCD4-PE40 for CHO-env in the presence or absence of added human serum was quantitated spectrophometrically following enzymatic reduction of a tetrazolium bromide within the mitochondria of viable cells (MTT assay). Several HIV+ sera inhibited the cytotoxic activity of sCD4-PE40; the antagonist had properties consistent with those of immunoglobulins in that it was heat stable, absorbed by protein A, and reversible by increasing the concentration of sCD4-PE40. Of 15 HIV+ sera which strongly reacted with gp120, 11 (73%) also potently inhibited sCD4-PE40 cytotoxicity, and cytotoxicity was inhibited by sera from some HIV- individuals after, but not before, immunization with gp160. These data suggested a role for antibody to gp120 in the antagonistic activity. However, not all sera with antibody to gp120 antagonized sCD4-PE40 cytotoxicity and high levels of antagonist activity were frequently (40%) found in HIV+ sera lacking immunoblot-detectable antibody to gp120, or antibody to either CD4 or PE40. Grouping of the HIV+ sera according to the patients' absolute number of CD4+ cells revealed that the degree of inhibition of sCD4-PE40 cytotoxicity approached a Gaussian distribution, suggesting that persons with CD4+ cell counts between 200 and 700/mm3 may be more likely to possess significant levels of serum antagonist. This data have implications for the clinical development of sCD4-PE40 or other sCD4-based therapeutics in the management of HIV-1 infection.

Enhancement of monocyte class I and II histocompatibility antigen expression in man by in vivo beta-interferon

Changes in monocyte cell-surface markers were assessed during treatment of patients with beta-interferon (beta-IFN). Immediately after isolation monocytes were analysed using monoclonal antibodies and flow cytometry. After 2 days of beta-IFN significant increases in major histocompatibility complex (MHC) related cell-surface products were observed while no changes in Leu-M3, a non-MHC associated monocyte-specific marker, were found. The most striking increases were (1) the percent of monocytes positive for HLA-DQ (mean increase = 19.7%); (2) the relative amount of monocyte-surface HLA-DR (mean increase = 10.1 mean fluorescence intensity (MFI) units); and (3) the relative amount of monocyte-surface beta 2-microglobulin (mean increase = 7.7 MFI units). Increases in MHC expression over baseline were greater after 2 days of beta-IFN treatment than after 14 days of IFN. Thus beta-IFN, produced by recombinant DNA technology and purified to homogeneity, increased surface MHC expression on monocytes in vivo. Additionally, levels of 2-5A synthetase, a type-I IFN-induced enzyme, were significantly increased in patient peripheral blood mononuclear cells after treatment. Increases in 2-5A synthetase were found to correlate with increases in MHC expression suggesting a common mechanism for induction. Flow cytometry can in the future be used to correlate changes in MHC expression with therapeutic response.

Modulation of 2',5'-oligoadenylate synthetase in patients treated with alpha-interferon: effects of dose, schedule, and route of administration

The interferon (IFN)-induced intracellular enzyme 2',5'-oligoadenylate (2-5A) synthetase was measured in extracts of peripheral mononuclear cells isolated from patients receiving a 300-fold range of doses of alpha interferon (IFN-alpha). The range of enzyme induction was 2.3- to 5.7-fold. The maximum fold increase varied from individual to individual as did the dose required for maximum enzyme stimulation. The magnitude and endurance of the enzyme response was a function of IFN dose and was unrelated to the duration of treatment or number of injections or to the route of administration. The enzyme assay was a more sensitive indicator of IFN administration than was measurement of the level of circulating IFN. These results substantiate the potential of a clinical 2-5A synthetase assay for monitoring IFN treatment.

Low doses of interferon alpha result in more effective clinical natural killer cell activation

To define critical parameters concerning interferon (IFN) effects upon natural killer (NK) cells in vivo, we gave cancer patients serial weekly intramuscular injections of purified lymphoblastoid IFN in six doses ranging from 10(5) to 3 X 10(7) U. Dose sequences were determined by randomly allocating patients to one of six levels in a latin square ordering scheme. NK cell stimulation, a threefold peak increase above preinjection levels of cytolysis (P = 0.022), occurred in peripheral mononuclear cells (PMC) sampled 24 h postinjection, of 3 X 10(6) U, but was not detectable at any dose in PMC sampled 7 d postinjection. No blunting occurred in NK cell responsiveness to repeated injection of IFN dosages a second time at or several weeks after study completion. At IFN doses of 3 X 10(6), 10(7), and 3 X 10(7) U, a negative correlation existed between the amount of IFN injected and the average extent of NK cell activation (r = -0.423, P less than 0.05). This contrasted with the progressively increasing response of NK cells to in vitro incubation with increasing concentration of up to 3,000 U/ml of IFN. Overnight culturing of PMC sampled before IFN injections resulted in a mean 1.9-fold increase in cytolytic activity (P = 0.0005) and a mean 53% decrease in variance (P = 0.024) between serial preinjection NK cell activity determinations. Cell separation procedures may, therefore, have resulted in NK cell inactivation, from which overnight culturing permitted recovery. We found that maximal NK cell activation at a low IFN dose, decreasing NK cell responsiveness at higher doses, and the need to culture PMC to efficiently detect NK cell boosting may account for disparities in reported effects of IFN on NK cell function.

Measurement of 2',5'-oligoadenylate synthetase in patients receiving interferon-alpha

The interferon-induced intracellular enzyme, 2',5'-oligoadenylate (2,5A) synthetase, was measured in extracts of Ficoll-purified human peripheral mononuclear cells from 28 normal healthy individuals and 14 patients receiving injections of interferon-alpha. Basal and stimulated levels could be measured reproducibly in 2 X 10(6) cells. In both groups, mononuclear cell levels of 2,5A synthetase varied widely, but measurements were reproducible in each individual. In most instances, increases in enzyme activity were detected within 8 h of interferon-alpha administration. Elevated levels persisted for at least 24 h and were maintained with daily treatment. In two of the 14 patients, the enzyme level failed to respond to multiple interferon injections. Interestingly, these two patients had pretreatment enzyme levels that were markedly elevated relative to those of a healthy population. Measurement of 2,5A synthetase levels is a valuable addition to clinical interferon studies, since the results may help to resolve questions of the optimal dose, route, and schedule of interferon administration.

Augmented antiproliferative effects of interferons at elevated temperatures against human bladder carcinoma cell lines

The in vitro antiproliferative effects of interferons (IFN) against the human bladder carcinoma cell lines T24, RT4, HT1197, and 647V were evaluated at temperatures ranging from 37-41 degrees. At 37 degrees, the antiproliferative activities of IFN, either naturally produced or produced by recombinant DNA technology, were different against different cell lines. An increase in temperature markedly enhanced the antimitotic effect of IFN for all cells. For example, T24 cells grown at 37 degrees and treated with 200 units naturally produced IFN-alpha or IFN-beta per ml for 7 days were inhibited 50 to 60%. No change in cell proliferation occurred in untreated T24 cells grown at 39.5 degrees. Treatment with 200 units IFN-alpha or IFN-beta per ml at 39.5 degrees inhibited these cells 80 to 90%. Similar results were obtained with IFN produced by recombinant DNA technology and purified to homogeneity. Colony formation by the RT4 cell line, at 37 degrees, was decreased less than 10% with 200 units IFN-alpha per ml and 63% by 200 units IFN-beta per ml. At 39.5 degrees, colony formation by untreated RT4 cells was inhibited 48%. Treatment with IFN-beta at 39.5 degrees did not result in an enhancement of the antiproliferative effect; however, treatment with IFN-alpha enhanced the inhibition from less than 10% to 98%. These results suggest that a supraadditive relationship exists between antiproliferative effects of IFN and temperature elevation. The differences seen between IFN-alpha and IFN-beta may be due to the different stabilities of these two molecules. In order to probe the mechanism of the enhanced antiproliferative effect, activity of an IFN-induced enzyme, 2'-5'-oligoadenylate synthetase, was measured. IFN-alpha treatment resulted in significantly greater 2'-5'-oligoadenylate synthetase induction at 39.5 degrees than at 37 degrees. Thus, two cellular effects resulting from IFN were augmented by increased temperature.

Transient neurologic dysfunction following moderate-dose methotrexate for undifferentiated lymphoma

Two patients, aged 24 and 19 years, who had undifferentiated lymphoma, developed the acute onset of focal neurologic deficits 10 days after treatment with moderate-dose methotrexate (2.76 g/m2 by 42-hour intravenous infusion) and 12.5 mg of intrathecal methotrexate. Prior chemotherapy also included intravenous cyclophosphamide, doxorubicin, vincristine, oral prednisone, and intrathecal cytosine arabinoside. Dysarthria with left hemiparesis was noted in one patient and inability to speak and quadriparesis in the other. Cerebrospinal fluid and cranial computerized tomography results were normal; however, EEGs showed focal abnormalities in both patients. Full neurologic recovery occurred within 48 hours. These symptoms developed early in the course of treatment and have not recurred in one patient who continued to receive the same regimen. The mechanism for this neurologic dysfunction is unclear. A similar picture has been reported in patients receiving high-dose methotrexate (8-10 g/m2) for osteogenic sarcoma.

Effects of diethyldithiocarbamate, an inhibitor of interferon antiviral activity, upon human natural killer cells

In support of a postulated role of the Cu++-dependent enzyme, superoxide dismutase (SOD), in antiviral effects of interferon (IFN), a close correspondence was previously shown to exist between inactivation of cellular SOD and concomitant blockade of IFN antiviral activity in fibroblasts by the Cu++-chelating agent, diethyldithiocarbamate (DDC). To further define the extent of "anti-IFN" activity, we initiated studies of DDC effects on IFN stimulation in the NK cell system. Unexpectedly, DDC directly inhibited cytotoxicity mediated by unstimulated NK cells. Pronounced inactivation occurred rapidly (less than 30 min), but was spontaneously reversible in the absence of DDC. Neither cell viability nor lymphocyte binding to target cells was detectably affected. Preincubation of DDC with Cu++ or Zn++ failed to neutralize its inhibitory effects nor could function be restored in DDC-pretreated NK cells by subsequent addition of Cu++, Zn++, Mg++, or Ca++. DDC treatment that inactivated NK cells did not detectably alter lymphocyte SOD activity. Thus, inhibition was probably not attributable to chelating properties of DDC. N-ethyl maleimide (NEM) and para-( hydroxymercuri ) benzoic acid ( PMBA ), enzyme inhibitors that preferentially react with sulfhydryl groups, both inactivated NK cells in a time- and dose-dependent manner similar to that of DDC. Preincubation with the sulfhydryl compound, cysteine, neutralized in parallel fashion the capacity of NEM, PMBA , and DDC to inhibit NK cell activity. Thus, a previously unreported reactivity of DDC with sulfhydryl groups appeared to be the basis of inhibition. NK cells incubated 1 hr with IFN and subsequently cultured 17 to 23 hr without IFN were activated to an extent comparable to cells continuously incubated 18 to 24 hr with IFN. Exposure to IFN for 1 hr was therefore sufficient to commit NK cells to acquisition of a fully activated state. Whether preactivated by a 1-hr or 18- to 24-hr IFN treatment, activated NK cells retained the DDC-sensitive phenotype characteristic of fresh unstimulated NK cells. Thus, prolonged IFN treatment did not render NK cells resistant to DDC or preferentially activate a DDC-sensitive NK cell subset. An 18- to 24-hr incubation of DDC-pretreated cells in the continual presence of IFN resulted in the boosting of NK cell activity. However, the 1-hr IFN pulse treatment protocol was consistently ineffective in boosting when IFN was added just after DDC-pretreatment. These results strongly suggested that DDC temporarily rendered NK cells unresponsive to what, under normal circumstances, approximated an optimally potentiating IFN stimulus.(ABSTRACT TRUNCATED AT 400 WORDS)

Effects of diethyldithiocarbamate, an inhibitor of interferon antiviral activity, upon human natural killer cells

In support of a postulated role of the Cu++-dependent enzyme, superoxide dismutase (SOD), in antiviral effects of interferon (IFN), a close correspondence was previously shown to exist between inactivation of cellular SOD and concomitant blockade of IFN antiviral activity in fibroblasts by the Cu++-chelating agent, diethyldithiocarbamate (DDC). To further define the extent of "anti-IFN" activity, we initiated studies of DDC effects on IFN stimulation in the NK cell system. Unexpectedly, DDC directly inhibited cytotoxicity mediated by unstimulated NK cells. Pronounced inactivation occurred rapidly (less than 30 min), but was spontaneously reversible in the absence of DDC. Neither cell viability nor lymphocyte binding to target cells was detectably affected. Preincubation of DDC with Cu++ or Zn++ failed to neutralize its inhibitory effects nor could function be restored in DDC-pretreated NK cells by subsequent addition of Cu++, Zn++, Mg++, or Ca++. DDC treatment that inactivated NK cells did not detectably alter lymphocyte SOD activity. Thus, inhibition was probably not attributable to chelating properties of DDC. N-ethyl maleimide (NEM) and para-( hydroxymercuri ) benzoic acid ( PMBA ), enzyme inhibitors that preferentially react with sulfhydryl groups, both inactivated NK cells in a time- and dose-dependent manner similar to that of DDC. Preincubation with the sulfhydryl compound, cysteine, neutralized in parallel fashion the capacity of NEM, PMBA , and DDC to inhibit NK cell activity. Thus, a previously unreported reactivity of DDC with sulfhydryl groups appeared to be the basis of inhibition. NK cells incubated 1 hr with IFN and subsequently cultured 17 to 23 hr without IFN were activated to an extent comparable to cells continuously incubated 18 to 24 hr with IFN. Exposure to IFN for 1 hr was therefore sufficient to commit NK cells to acquisition of a fully activated state. Whether preactivated by a 1-hr or 18- to 24-hr IFN treatment, activated NK cells retained the DDC-sensitive phenotype characteristic of fresh unstimulated NK cells. Thus, prolonged IFN treatment did not render NK cells resistant to DDC or preferentially activate a DDC-sensitive NK cell subset. An 18- to 24-hr incubation of DDC-pretreated cells in the continual presence of IFN resulted in the boosting of NK cell activity. However, the 1-hr IFN pulse treatment protocol was consistently ineffective in boosting when IFN was added just after DDC-pretreatment. These results strongly suggested that DDC temporarily rendered NK cells unresponsive to what, under normal circumstances, approximated an optimally potentiating IFN stimulus.(ABSTRACT TRUNCATED AT 400 WORDS)

Comparison of the biologic effects of two recombinant human interferons alpha (rA and rD) in humans

IFN-alpha (rD) was investigated to determine the relationship between antiviral activity in vitro and the modulation of biologic effects in vivo. Eight patients with malignancy were given 15 and 45 micrograms weekly injections of IFN-alpha (rA) and IFN-alpha (rD). The frequency of side effects was much lower with IFN-alpha (rD) injections. This was objectively documented both in incidence of side effects (20 versus 45, p less than 0.01) and mean maximum temperature (1 degree C lower with IFN-alpha (rD), p less than 0.002). A bovine cell line, MDBK, was used to measure interferon concentrations in the serum. Geometric mean peak titers and time-to-peak titers were similar with the two recombinant interferon preparations. Although IFN-alpha (rD) has relatively less antiviral activity on human cells, its effect on the total granulocyte count, natural killer (NK) cell cytotoxicity, and 2'5'-A activity was comparable to IFN-alpha (rA). Mean NK cell percent specific 51Cr release was enhanced by both interferons (after 15 micrograms doses, mean percent NK cell cytotoxicity IFN-alpha (rD) preinjection, 10.5% +/- 2.3%; post-injection, 27.2% +/- 4.5%; IFN-alpha (rA), preinjection, 14.4% +/- 3.2%, postinjection, 25.1% +/- 5%). Species-specific antiviral activity of an interferon does not necessarily predict other biologic properties following in vivo administration.

Decreased monocyte function in patients with Hodgkin's disease

Monocyte function in nine untreated and nine treated patients with Hodgkin's disease in different stages was studied simultaneously with normal controls. Monocyte chemotactic responses were decreased in 6 of the 14 patients with advanced disease regardless of previous therapy. None of our patients with stage II disease had abnormal results. Decreased monocyte chemotactic responses correlated with the presence of cutaneous anergy. In addition, decreased chemotaxis was associated with diminished monocyte bactericidal activity. This suggests that decreased bactericidal activity may be related to abnormal migration and possible diminished ingestion. The data support the hypothesis that depressed monocyte function may contribute to the increased susceptibility to infections of patients with Hodgkin's disease and it may be an additional factor favoring tumor dissemination in the advanced stages of the disease.

Monoclonal macroglobulinemia with osteolytic lesions: a case report and review of the literature

A patient with monoclonal macroglobulinemia and osteolytic lesions was studied and 24 previously reported closely related cases were reviewed. Cases studied by ultracentrifugation without an immunoelectrophoresis were not considered. Patients presenting with a primary increase in monoclonal IgM molecules may be divided into three groups: typical Waldenstrom's macroglobulinemia, macroglobulinemia with osteolytic lesions resembling multiple myeloma, and a group displaying features of both diseases. At present, cell morphology is not helpful in separating these groups, and a bone survey is recommended. The authors underscore the clinical importance of the early recognition of these entities since procedures such as plasmapheresis for the management of hyperviscosity syndrome, mobilization and local radiotherapy to symptomatic lytic lesions may be necessary for optimal management.

The use of a multipath cell as a CO(2)-N gas laser amplifier and oscillator

A multipath cell using a modified White mirror system has been operated as an amplifier and as an oscillator at the 10.6-micro CO(2) transition of the CO(2)-N(2) gas laser. An oscillator tube efficiency of 33% and an amplifier power gain of 8.7 have been obtained. With a specific gas mixture, the amplifier saturated output power is approximately one-half that of the maximum oscillator output.