Biosafety investigations in an r-DNA production plant

Employees of a biotechnological production plant for recombinant interferon alpha-2a have been participating in a 1-year study on occupational hygiene and the resulting biosafety aspects. Most of the employees have been employed in the plant for more than 6 years. Weekly stool samples were analysed for tetracycline (used as selection marker)-resistant coliforms as well as for rDNA (IFN gene) (interferon gene) and for the production organism. Various analytical methods, including the polymerase chain reaction, were applied to show that neither rDNA nor the production organism could be found in any of the stool samples and that there was no change or trend in the gut flora with respect to tetracycline resistance. In addition it could be shown that the tetracycline-resistance gene, as well as the rDNA, are completely inactivated in the course of the production process and thus no further recombination can take place. Blood samples were taken to show that none of the employees had anti-product antibodies.

Interferon-alpha stimulates the hypothalamic-pituitary-adrenal axis in vivo and in vitro

The successful therapeutic use of interferon-alpha (IFN-alpha) in myeloproliferative disorders offered the possibility to test its acute and long-term effects on the hypothalamic-pituitary-adrenal (HPA) axis in humans. ACTH and cortisol plasma concentrations were measured in 8 patients hourly starting from 4 p.m. through 12 p.m. on three occasions. The first time all patients were studied before initiation of therapy, when the vehicle was injected alone. The patients were studied again on day 1 of IFN-alpha therapy (5 million units) and once more after 3 weeks of therapy. On the control day, plasma concentrations of ACTH and cortisol were in the range expected for this time of day. In contrast, after the first administration of IFN-alpha a significant stimulation of the HPA axis was observed. After 3 weeks of IFN-alpha therapy, no significant stimulation of the HPA axis occurred after administration of IFN-alpha. IFN-alpha-induced adaptive changes in the HPA axis were also indicated by a significantly enhanced ACTH and cortisol response to exogenously administered supramaximal doses of corticotropin-releasing hormone (CRH) when the patients had been on IFN-alpha treatment for 3 weeks. To determine the exact locus of the IFN-alpha action, in vitro experiments were performed using rat hypothalamic organ and primary pituitary and adrenal cell culture systems. Thereby a significant stimulation of hypothalamic CRH secretion and rat adrenal corticosterone production was observed after INF-alpha at concentrations of 5 x 10(-8) M or 10(-7) M respectively. In contrast, no direct IFN-alpha effect on pituitary ACTH secretion could be observed in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)

Incidence of infections in pigs bred for slaughter revealed by elevated serum levels of interferon and development of antibodies to Mycoplasma hyopneumoniae and Actinobacillus pleuropneumoniae

Pigs in three specialized fattening herds were studied with respect to some immune functions, viral infections revealed by presence of interferon-alpha in serum as well as bacterial infections indicated by antibodies to Mycoplasma hyopneumoniae and Actinobacillus pleuropneumoniae. Pigs from different breeders had signs of varying but low incidence of such infections. After transport to the fattening herds, viral infections were activated and spread during the first month, and a maximum of 19% of the pigs had signs of ongoing infections at one week. At this time, blood leukocytes prepared from the pigs had diminished ability to produce interferon-alpha in vitro. Except during the first month, serological evidence of Mycoplasma hyopneumoniae infections became gradually more frequent, and 91% of the pigs were seropositive at slaughter. Early, but not late, infections appeared to inhibit growth of the pigs as indicated by time for slaughter, but only late infections may be registered as pneumonia at slaughter. The prevalence of pigs with serological evidence of Actinobacillus pleuropneumoniae infections increased late in the fattening period, but such infections had no demonstrable impact on the time for slaughter.

High levels of interferon alpha in the sera of children with dengue virus infection

We measured the levels of interferon alpha (IFN alpha) in the sera of Thai children hospitalized with dengue hemorrhagic fever (DHF) or dengue fever (DF) to examine the role of IFN alpha in dengue virus infections of humans. The percentage of patients who had detectable levels of IFN alpha (> or = 3 U/ml) was higher in patients with DHF (80%, P < 0.001) and in patients with DF (60%, P < 0.001) than in healthy Thai children (7%). The levels of IFN alpha were higher in patients with DHF and in patients with DF on the first few days after the onset of fever than in healthy Thai children. The average levels of IFN alpha in patients with DHF were high two days before defervescence, decreasing gradually until the day of defervescence. There was a subset of patients with DHF who had increasing levels of IFN alpha after defervescence. However, the levels of IFN alpha in patients with DF were not high after fever subsided. The levels of IFN alpha were not different among children with DHF grades 1, 2 and 3. Among patients with DHF, T lymphocytes were activated to a higher degree in high IFN alpha producers than in low IFN alpha producers. These results indicate that similarly high levels of IFN alpha are produced in vivo during the acute stages of DHF and DF, and that high levels of IFN alpha remain after fever subsides in some patients with DHF, but not in patients with DF.

Natural killer cell cytotoxicity and alpha-interferon in early rheumatoid arthritis

Natural killer (NK) cell number, cytotoxicity, and serum alpha-interferon (alpha-IFN) was measured in a group of early synovitis patients and compared to that of established rheumatoid arthritis patients and normal controls. No significant differences in NK cell number or serum alpha-IFN were found. NK cell cytotoxicity (NKCC) in the early synovitis group was significantly (p < 0.05) reduced compared to that of the normal controls and not significantly different from the established rheumatoid controls. There was a trend for those early synovitis patients with a good outcome to have higher NKCC. Low NKCC is evident very early in the course of rheumatoid arthritis and is thus unlikely to be secondary to chronic inflammation. There is no relationship between NKCC and alpha-IFN levels and the cause of the reduced NKCC is unknown. Alpha-IFN levels are not raised early in the course of RA.

[Interferon and blood tumor necrosis factor in 95 patients with HIV infection]

We have measured TNF-alpha and interferon alpha in 95 HIV positive patients and 20 healthy subjects. TNF-alpha was higher in the HIV+ patients (P = 0.0001) and was correlated to the CD4 cell count (P = 0.02) and cholesterol (negatively) (P = 0.04). Interferon-alpha was correlated to the wasting syndrome (P = 0.002), hypertriglyceridemia (P = 0.004) and haematocrit (P = 0.04).

Raised levels of tumour necrosis factor-alpha and neopterin, but not interferon-alpha, in serum of HIV-1-infected patients from Ethiopia

Serum levels of tumour necrosis factor-alpha (TNF-alpha), neopterin and interferon-alpha (IFN-alpha) were determined by immunoradiometric assays in 60 HIV-1+ and 20 HIV-1- subjects from Ethiopia. Swedish samples were used as reference material. The Ethiopian HIV-1+ subjects were found to have significantly increased TNF-alpha and neopterin, but not IFN-alpha levels. Increased levels of TNF-alpha and neopterin were frequently found in Ethiopian asymptomatic subjects (37% and 47%), and the concentration increased in patients with AIDS (83% and 90% respectively). The levels of the two substances and the proportion of patients with higher TNF-alpha values were lower in the corresponding Swedish subjects. The proportion of sera with raised levels of IFN-alpha was very low (asymptomatic 4%, and AIDS 7%) in Ethiopian subjects. These results suggest a very early increase in the TNF-alpha production and activation of the cellular immune response, and a low level of IFN-alpha synthesis in the natural course of HIV infection in Ethiopia. The aberrations may contribute to a rapid progress of immunodeficiency and cachexia often seen in Ethiopian patients.

Pharmacokinetics of an extended-release human interferon alpha-2b formulation

The in vivo half-life of human interferon alpha-2b (hIFN-alpha-2b) is relatively short, and frequent injections over prolonged periods are required for efficacy. An extended-release formulation of hIFN-alpha-2b (Depo/IFN) was created by encapsulation into a lipid-based drug-delivery system. The capture efficiency was 51% +/- 13% and the release half-life in human plasma at 37 degrees C was 16 days. The pharmacokinetics of Depo/IFN was compared with that of unencapsulated standard hIFN-alpha-2b (Std/IFN) in the peritoneal cavity of male BDF1 mice. Depo/IFN exhibited a 13-fold longer intraperitoneal (i.p.) half-life as compared with Std/IFN (20 vs 1.5 h). The release of free hIFN-alpha-2b from Depo/IFN into the peritoneal cavity was slow and protracted, with a 10-fold lower peak concentration and a 13-fold longer apparent half-life being observed in comparison with Std/IFN. The areas under the curve of free hIFN-alpha-2b in the peritoneal cavity were comparable for Depo/IFN and Std/IFN. hIFN-alpha-2b was detectable in plasma only after the i.p. administration of Std/IFN. These data suggest the possibility that Depo/IFN may be useful as an extended-release formulation of hIFN-alpha-2b.

Short-term responsiveness of membranous glomerulopathy to cyclosporine

We administered a 12-week course of cyclosporine (CsA) (4 to 6 mg/kg/24 h) to nephrotic patients with membranous glomerulopathy (MG). Nephrotic patients with minimal change nephropathy (MCN) served as a comparison group. We evaluated the effects of CsA on proteinuria, glomerular function, and the release of cytokines by peripheral blood mononuclear cells in culture. Proteinuria was restored to normal levels within 2 to 4 weeks in MCN. Proteinuria declined from nephrotic to subnephrotic levels (< 3,500 mg/24 h) in 10 of 14 patients with MG, also within 2 to 4 weeks of onset of therapy. The four nonresponders exhibited a rapidly progressive and presumably irreversible form of MG culminating in renal failure. On average, fractional clearances of albumin and IgG declined by 59% and 73% in MG (P < 0.005); corresponding declines in MCN were by 99% (P < .0001). Corresponding rates of glomerular filtration in each glomerular injury remained unchanged. A strong trend for proteinuria to relapse after CsA was withdrawn was evident in both disorders. The release of tumor necrosis factor (TNF)-alpha by mononuclear cells in culture was enhanced in each glomerular injury, both before and after the course of CsA. We conclude that the proteinuria in most cases of MG exhibits a responsiveness to CsA that is qualitatively similar to, but less complete than, that in MCN. The rapidity with which barrier function improves suggests a possible role for cell-mediated immune injury in MG.

In-vitro resistance to zidovudine and alpha-interferon in HIV-1 isolates from patients: correlations with treatment duration and response

OBJECTIVE

To measure in-vitro antiviral drug susceptibilities of human immunodeficiency virus type 1 (HIV-1) isolates recovered from patients treated with alpha-interferon or zidovudine and patients not treated with these drugs and to examine the relation of these susceptibility measurements to duration of therapy, disease stage, and response to alpha-interferon therapy.

DESIGN

Cross-sectional study.

SETTING

Outpatient HIV clinic.

PATIENTS

Twenty-six ambulatory HIV-1-infected patients: Fifteen of these patients were receiving alpha-interferon therapy, and 11 had never received such therapy. Nine patients were participating in a clinical trial of combination therapy with zidovudine and alpha-interferon.

MEASUREMENTS

The 50% inhibitory concentration (IC50) of zidovudine and alpha-interferon was determined for HIV-1 isolates recovered from each patient. Plasma concentrations of HIV-1 p24 antigen in the nine patients in the clinical trial were measured monthly after alpha-interferon was added to zidovudine monotherapy.

RESULTS

Zidovudine IC50 (range, 0.01 to 4.87 microM) increased steadily with duration of zidovudine therapy (r = 0.57, P = 0.003). In contrast, alpha-interferon IC50 (range, 0.8 to 415 units/mL) was not related to duration of alpha-interferon treatment; in fact, high IC50s were found in isolates from patients who had never received exogenous alpha-interferon therapy. Resistance to alpha-interferon was greater in isolates from the 15 patients with the acquired immunodeficiency syndrome (AIDS) (median, 104 units/mL) than in those from the 10 patients without AIDS (median, 50 units/mL). Interferson activity was detected in plasma samples from 23 of 24 patients and was also at higher levels in patients with AIDS than in HIV-infected patients without AIDS. Reductions in plasma concentrations of HIV-1 p24 antigen in nine patients after beginning alpha-interferon therapy were greater in those with more susceptible isolates (r = -0.72, P = 0.03).

CONCLUSIONS

Interferon resistance, possibly due to endogenous interferon, is not related to duration of interferon therapy but may limit the effectiveness of interferon therapy. Determinations of interferon susceptibility may identify patients most likely to benefit from this agent.

Poly I:C accelerates development of diabetes mellitus in diabetes-prone BB rat

We developed a new experimental model of accelerated diabetes mellitus in the genetically susceptible diabetes-prone BB rat with the administration of the IFN-alpha inducer poly I:C. With this model, there was both an increased incidence and accelerated onset of insulin-dependent-diabetes in poly I:C-treated animals compared with saline-treated controls. All twelve rats administered poly I:C (5 micrograms/gm body weight 3 times/wk) developed diabetes by 57 days of age (100%) compared with 1 of 27 (3.7%) saline-treated controls. Furthermore, the development of diabetes was accelerated in the poly I:C-treated group (mean age +/- SE at onset 52.8 +/- 0.58 days) compared with saline-treated controls (89.3 +/- 2.4 days, P less than 0.01). Additionally, poly I:C-treated rats had higher mean serum IFN-alpha levels than saline-treated rats at weeks 2 and 3 of treatment (210 vs. 27 and 183 vs. 25 U/ml, respectively, P less than 0.001). Poly I:C treatment of 5 Wistar rats, the parental strain, which is not susceptible to diabetes, did not result in insulitis, diabetes, or hyperglycemia. The histopathologic findings of insulitis and decreased immunoreactive islet insulin in poly I:C-accelerated diabetic BB rats and in BB rats with spontaneous diabetes suggest a similar pathophysiology.

Serum interleukin-2 receptor and interferon-alpha levels in a patient with allergic granulomatous angiitis (Churg-Strauss)

A patient with allergic granulomatous angiitis accompanied by increases in serum interleukin-2 receptor (IL-2R) and interferon-alpha (IFN-alpha) levels is reported. Laboratory findings revealed leukocytosis with eosinophilia and increased serum IgE and IgG. The serum IL-2R and IFN-alpha were increased. The serum immune complex, interferon-beta, -gamma and complements remained at normal levels. The serum IgE, IgG, IL-2R and IFN-alpha correlated with disease activity. Immunofluorescent studies using frozen sections obtained from the dermal lesion showed no immunoglobulin or complement deposits on vascular walls. Measurements of serum IL-2R and IFN-alpha might be considered reliable serologic indicators of disease activity.

Ganoderma tsugae mycelium enhances splenic natural killer cell activity and serum interferon production in mice

Effects of the water-soluble extract of Ganoderma tsugae mycelium (GT), its alcohol-insoluble subfraction (GTI), and its alcohol-soluble subfraction (GTS) on splenic natural killer (NK) cell activity and serum interferon (IFN) production were assessed in mice. Intraperitoneal administration of GT (4-200 mg/kg) or GTI (1-50 mg/kg), but not GTS, augmented the NK cytotoxic activity in a dose-dependent manner in C3H/HeN mice. This augmentation of splenic NK cytolytic activity was not mouse-strain-dependent. The serum IFN titers of mice were also elevated after i.p.-doses of GTI. The GTI-induced serum IFN was reduced by either IFN-(alpha+beta) antiserum or IFN-gamma monoclonal antibody in vitro. The treatment with antiserum neutralizing IFN-(alpha+beta) resulted in a 70% reduction of GTI-induced IFN, while monoclonal antibody against mouse IFN-gamma, moderately neutralized the GTI-induced IFN (50%). These results demonstrated that both the splenic NK activity and serum IFN [IFN-(alpha+beta) and IFN-gamma] titers are elevated by Ganoderma tsugae mycelium extracts in mice.

Serum levels of lymphokines and soluble cellular receptors in primary Epstein-Barr virus infection and in patients with chronic fatigue syndrome

The immunopathology in primary Epstein-Barr virus (EBV) infections and in chronic fatigue syndrome was studied by examining serum levels of interleukins (IL) and of soluble T cell receptors in serum samples. Serum samples were from patients during and 6 months after primary EBV-induced infectious mononucleosis and from patients with chronic fatigue syndrome and serologic evidence of EBV reactivation. Markers for T lymphocyte activation (soluble IL-2 and CD8) and for monocyte activation (neopterin) were significantly elevated during acute infectious mononucleosis but not in patients with chronic fatigue syndrome. Interferon-alpha, IL-1 beta, and IL-6 levels were not significantly increased in any patient group but inferferon-gamma levels were significantly increased during the acute phase of infectious mononucleosis. The levels of IL-1 alpha were significantly higher than in controls both in patients with infectious mononucleosis and in those with chronic fatigue syndrome. In the latter, the lack of most markers for lymphocyte activation found in patients with infectious mononucleosis makes it less likely that EBV reactivation causes symptoms.

Lipids, lipoproteins, triglyceride clearance, and cytokines in human immunodeficiency virus infection and the acquired immunodeficiency syndrome

Infection causes disturbances in lipid metabolism that may be mediated by cytokines. Therefore we studied plasma lipids, lipoproteins, triglyceride (TG) metabolism, and serum cytokines in three groups: patients with the acquired immunodeficiency syndrome (AIDS) without active secondary infection, patients with evidence of human immunodeficiency virus infection but without clinical AIDS (HIV+), and controls. Plasma TGs and FFA were increased in AIDS, while plasma cholesterol, high density lipoprotein (HDL) cholesterol, apolipoprotein-A-1 (Apo-A-1), low density lipoprotein (LDL) cholesterol, and Apo-B-100 levels were decreased. Increased TG levels in AIDS were primarily due to increases in very low density lipoprotein of normal composition; in addition, LDL and HDL were TG enriched. In HIV+, TGs and FFA were not increased, but total cholesterol, HDL cholesterol, Apo-A-1, and Apo-B-100 were significantly decreased. Interferon-alpha (IFN alpha) and C-reactive protein levels were increased in AIDS, but tumor necrosis factor and haptoglobin levels were not. There was a significant correlation between plasma TGs and IFN alpha levels (r = 0.477; P less than 0.01), but not between TGs and tumor necrosis factor, C-reactive protein, haptoglobin, or P-24 antigen. In addition, there was no relationship between circulating IFN alpha levels and plasma cholesterol, HDL cholesterol, Apo-A-1, LDL cholesterol, Apo-B-100, or FFA. TG clearance time and postheparin lipase were significantly decreased in AIDS and HIV+. There was a strong correlation between serum IFN alpha levels and TG clearance time in AIDS and HIV+ (r = 0.783; P less than 0.001). In summary, decreases in cholesterol and cholesterol containing lipoproteins (including HDL) in both AIDS and HIV+ precede the appearance of hypertriglyceridemia and are not related to IFN alpha or TG levels. Our data raise the possibility that with development of AIDS, subsequent increases in IFN alpha may contribute to increases in plasma TG levels in part by decreasing the clearance of TG.

Production of interferon by peripheral blood mononuclear cells from normal individuals and patients with chronic lymphocytic leukemia

Peripheral blood mononuclear cells (PBMC) from normal individuals were studied to identify which cells produce alpha-interferon (IFN-alpha) in response to a virus stimulus. It was found that cells both adherent and nonadherent to plastic formed IFN-alpha after induction by any one of several viruses studied. When nonadherent cells were separated on discontinuous Percoll gradients, only the cells in the less dense Percoll fractions produced IFN, whatever the virus used. By indirect immunofluorescence with monoclonal antibodies to HLA-DR and to Leu 11b, the distribution of the HLA-DR+ cells was shown to resemble most closely that of the IFN-producing population. Elimination of these cells (by complement-mediated lysis with the same antibodies) abrogated the IFN response, but NK cells remained and thus do not produce IFN-alpha. In confirmation, elimination of the Leu 11b+ cells had no effect on the amount of IFN produced. PBMC preparations from patients with chronic lymphocytic leukemia (CLL) appeared incapable of producing IFN-alpha but were shown to contain identifiable IFN-producing cells. The low or absent IFN levels in CLL are probably due to the relative scarcity of IFN-producing cells in their PBMC.

In vivo levels and in vitro production of interferon-gamma in fibrosing interstitial lung diseases

The in vivo role of interferons in the development of fibrosis is not fully understood but it is known that interferons can suppress fibroblast proliferation and collagen synthesis in vitro. We have recently demonstrated that in a group of patients with sarcoidosis having predominant pulmonary involvement, patients with the highest levels of circulating interferon-gamma (IFN-gamma) more frequently resolved on corticosteroids, suggesting that they had a less 'fibrotic' component to their disease. We now report that in two other diseases, where the tendency to develop pulmonary fibrosis is greater than in sarcoidosis, namely cryptogenic fibrosing alveolitis (CFA) and fibrosing alveolitis associated with the systemic connective tissue disease progressive systemic sclerosis (FA + PSS), very few patients have elevations in IFN-gamma in their serum. However, as in sarcoidosis, those with the highest levels responded to corticosteroids (P less than 0.05). Attempts to measure IFN-gamma levels in the lungs, using cell-free bronchoalveolar lavage (BAL) fluid supernatants, were negative in all the study groups, suggesting that these samples may be inadequate for such studies. To investigate whether there might be an intrinsic defect in T lymphocyte function associated with predisposition to fibrosing lung diseases, we then investigated the in vitro production of IFN-gamma by lymphocytes separated from the blood of 18 untreated patients (six with CFA, six with FA + PSS and six with sarcoidosis). IFN-gamma production was impaired in 10 (56%) (two with CFA, four with FA + PSS and four with sarcoidosis). A higher proportion of the fibrosing alveolitis patients (CFA or FA + PSS) with impaired IFN-gamma production have subsequently shown spontaneous lung functional deterioration. These findings suggest that impaired IFN-gamma release might be a potentiating factor in the pathogenesis of these fibrosing lung diseases.

Correction of HIV-associated thrombocytopenia with low doses of interferon alfa

We have presented a case of HIV-associated thrombocytopenia successfully treated with low dose interferon alfa-2a. Increases in platelet levels were achieved within 1 week without hospitalization or surgery. Further, the patient had no systemic side effects from therapy. Zidovudine alone was ineffective in maintaining noncritical platelet counts. Interferon alfa-2a is a nonimmunosuppressive, nonsurgical therapy that can correct HIV-associated thrombocytopenia without requiring hospitalization.

Interferon-alpha in lupus psychosis

OBJECTIVE

Since the level of interferon-alpha (IFN alpha) is increased in the sera of patients with active systemic lupus erythematosus (SLE) and is detectable in the cerebrospinal fluid (CSF) of some SLE patients with neuropsychiatric manifestations, we investigated the contribution of IFN alpha to the pathogenesis of the neuropsychiatric manifestations of SLE.

METHODS

IFN alpha levels were quantitated by radio-immunoassay in CSF and serum samples from 17 SLE patients with neuropsychiatric manifestations and 28 patients with SLE alone or SLE and other neurologic disorders.

RESULTS

Levels of IFN alpha were increased in the CSF of 5 of 6 patients with lupus psychosis, and in 4 of these 5 patients, the levels in CSF were higher than those in serum. IFN alpha levels decreased when the manifestation of lupus psychosis subsided. In contrast, IFN alpha levels in CSF samples from patients with seizures alone were not increased. One patient with lupus psychosis died of complications of generalized seizures resulting from the SLE. At autopsy, we investigated whether IFN alpha protein or messenger RNA was detectable in the subject's brain. IFN alpha protein was immunohistochemically demonstrated in the neurons and in the microglia (focal accumulation), features not present in the brain tissues of subjects who died of other diseases.

CONCLUSION

These findings support the hypothesis that IFN alpha, possibly synthesized in the brain, is the cause of the manifestation of psychosis in patients with SLE.

Intrapleural application of natural IFN alpha in breast cancer patients with pleural carcinomatosis. Monitoring of immunotherapy by assaying serum interferon levels

For resistant local recurrence, e.g. in breast cancer, or metastatic spread, local infiltration of IFN may be an interesting new approach. The aim of this study was to find out if intrapleurally administered interferon, in breast cancer patients with pleural carcinomatosis, can cause measurable serum concentrations and how soon after administration. Serum IFN concentrations were compared with those in the pleural fluid, and correlated with the presence of malignant cells in the pleural fluid. To uncover possible rhythmicity of serum interferon levels and its relationship to the timing of therapy, natural leukocyte interferon was administered intrapleurally at 10 a.m. Data on pharmacokinetics were obtained from blood samples drawn at -2, 0, 2, 8, 14, 22 and 46 h during the course of treatment. In contrast to our previous observations in healthy volunteers, levels of serum IFN before therapy had no circadian rhythmicity. Daily pharmacokinetic profile of individual patients on interferon therapy has shown that serum IFN peaks 8 h after intrapleurally administered IFN alpha. The peak depended on frequency and number of applied doses. During treatment with IFN alpha, malignant cells degenerated and finally disappeared from pleural fluid. At the same time reactive cells appeared. This effect is rather uniformly observed, but varies in degree. The number of patients is too small, however, to permit conclusions in regard to correlation of this clinical effect and the levels of serum IFN alpha.

Abnormalities in serum concentrations of interleukin-2, interferon-alpha and interferon-gamma in schizophrenia not detected

The hypothesis of an immunological defect in schizophrenia has been supported by reports on abnormal production of interleukin-2 (IL-2) and interferons (IFNs) in schizophrenic patients. In the present study we determined the serum concentrations of IL-2, IFN-alpha and IFN-gamma in 10 first onset, neuroleptic-naive schizophrenics, in 6 pretreated patients who were drug free (1 week to 2 years) at the time of the investigation and in 15 matched healthy controls. No IFN-alpha was detected in schizophrenics' and in control sera. No differences were found in IL-2 and IFN-gamma levels between schizophrenics and controls. Thus the present study failed to support the hypothesis of an immunological abnormality in schizophrenia on the basis of the determination of IL-2 and IFNs serum levels.

Comparison of mitogen- and virus-induced interferon production in whole blood cell cultures of patients with various solid carcinomas and controls

Using a sensitive immunoassay, the mitogen-induced production of interferon-gamma (IFN-gamma) and virus-stimulated IFN-alpha production was investigated in whole blood cell cultures of 115 control subjects and 225 untreated patients with various solid carcinomas. In the cultures of the tumor patients, significantly lower levels of IFN-gamma were found as compared to the controls (p < or = 0.001) and the differences were most evident in those tumor groups containing mostly patients with advanced clinical stages. IFN-alpha values were only slightly lower in the cultures of the carcinoma patients, with p values < or = 0.05. Statistically, there was no correlation between IFN-alpha and IFN-gamma values. Since the IFN-gamma differences between tumor and controls and the correlation to groups with higher tumor stages were much clearer than IFN-alpha differences, we conclude that IFN-gamma measurements after polyclonal induction may be the better parameter for showing a depressed cellular immunological activity in patients with malignancies than virus-induced IFN-alpha secretion.

A sensitive immunoassay for porcine interferon-α

Two murine monoclonal antibodies (mAbs) directed against different epitopes on recombinant porcine interferon-alpha (IFN-alpha) were selected and used to construct a two-site ELISA. This ELISA, when performed in a one-step version, detected about 0.5 units ml-1 of IFN-alpha and showed similar sensitivity but better precision than a cytopathic effect inhibition bioassay. Estimates of IFN-alpha in tissue culture medium by the two assays correlated well. In contrast, one or several factors in porcine serum reduced the sensitivity of the ELISA. Measurements of IFN-alpha in porcine serum was, however, possible in a two-step version of the ELISA, with a sensitivity of about 1 unit IFN-alpha ml-1. Results of ELISA and bioassay agreed, except that the ELISA possibly produced false positive results in two out of a total of 91 sera negative in the bioassay. In addition, one of 23 sera positive in the bioassay was negative in the ELISA.

Systemic lymphoblastoid interferon therapy in chronic progressive multiple sclerosis. II. Immunologic evaluation

Immunologic functions are studied in conjunction with a placebo-controlled trial of lymphoblastoid interferon (IFN) in patients with chronic progressive (CP) multiple sclerosis. Prior to treatment, CD4+ cells are significantly increased and CD8+ cells decreased in the blood of MS patients. Both CD5+ and CD4+ cells increase significantly with IFN therapy early during the treatment phase of the trial, while the number of CD8+ cells decreases steadily, becoming significant at 6 months. CNS IgG synthesis rates increase with IFN treatment and maximize at 3 months. Serum antiviral activity also increases with IFN treatment. In the IFN-treated group, a trend toward improvement, determined clinically and by MRI, likely reflects the influence of a subpopulation of 10 patients. This subpopulation is now further characterized by an early increase in CNS IgG synthesis and numbers of CD5+ cells in the blood. Although these immune functions may identify a number of CP MS patients who might benefit from IFN, it is unlikely that these mechanisms actually mediate the potentially beneficial effects of this cytokine.