A phase I/II dose-escalation study of herpes simplex virus type 1 thymidine kinase "suicide" gene therapy for metastatic melanoma. Study Group on Gene Therapy of Metastatic Melanoma

We performed a dose-escalating phase I/II study of retrovirus-mediated herpes simplex virus type 1 thymidine kinase (HSV-1-TK) suicide gene therapy for metastatic melanoma. HSV-1 TK expression, which specifically sensitizes transduced and bystander cancer cells to ganciclovir (GCV) toxicity, was mediated by one (four patients, first dose step) to three (four patients, second dose step) injections of "M11" retrovirus vector-producing cells in melanoma cutaneous nodules. After a 7-day period allowed for cancer cell transduction, GCV was administered for 14 days. Safety was assessed by clinical and laboratory evaluations, and efficacy was assessed by tumor measurements and histology. M11 doses ranged from 76 to 1247 x 10(6) cells. Treatment-related adverse events were mild and transient, limited to inflammatory skin reactions at injection and fever on repeated injections. Plasma GCV was in the active range (>0.2 microg/ml); transgene was detected by polymerase chain reaction in three of six patients; treated tumor size was moderately affected under GCV as compared with untreated tumors, although 2 weeks after GCV administration important (>50%) treated-tumor necrosis was evidenced on histology in three of eight patients. All patients showed disease progression on long-term follow-up. Thus, M11-mediated HSV-1 TK gene therapy was well tolerated over a wide dose range. The limited tumor response is likely to be related to poor gene transfer efficiency. However, necrosis following GCV administration in transduced tumors indicates a potential for treatment efficacy.

Cerebral Erdheim-Chester disease: report of two cases with progressive cerebellar syndrome with dentate abnormalities on magnetic resonance imaging

Two patients with Erdheim-Chester disease with progressive cerebellar dysfunction and pyramidal signs are reported on. Cerebral MRI showed bilateral increased signal intensity in peridentatal regions on T2 weighted sequences. Both patients had kidney and bone involvement, established on bone biopsy for one. One patient improved with steroid therapy. This contrasts with previous reports, which describe rare neurological manifestations and the failure of different therapeutic approaches.

Susceptibility of peripheral blood mononuclear cells to apoptosis is correlated to plasma HIV load

OBJECTIVES

To quantify spontaneous and activation-induced apoptosis in peripheral blood mononuclear cells (PBMC) of HIV-infected patients and to look for correlations between PBMC apoptosis levels, stages of HIV disease, CD4 count, and plasma viral load.

STUDY POPULATIONS

75 consecutive inpatients and outpatients infected with HIV (mean CD4 count, 202 +/- 182 x 10(6)/L; mean plasma viral load, 4 +/- 1.29 log10 RNA copies/ml) and a control group composed of 18 healthy, HIV-negative adults.

METHODS

Spontaneous apoptosis was detected at the single-cell level by direct incorporation of fluorescein-deoxyuridine triphosphate (dUTP) in PBMC DNA strand breaks. Activation-induced apoptosis was determined after in vitro stimulation with anti-CD3 antibodies and interleukin-2 (IL-2).

RESULTS

Spontaneous apoptosis was low in patients and controls, whereas activation-induced apoptosis was significantly higher in HIV-infected patients (5.22 +/- 4.32% versus 2.46 +/- 1.77%, respectively; p = .009). The degree of activation-induced apoptosis was positively correlated with the plasma viral load (r = 0.29; p = .029) and negatively correlated with the CD4 count (r = -0.37; p = .0009). Although activation-induced apoptosis was significantly higher in patients fulfilling AIDS criteria, it did not differ significantly between patients with an acute AIDS-defining event and those with stable disease.

CONCLUSION

Susceptibility of PBMC to apoptosis in HIV-1-infected patients is correlated to the plasma viral load and the stage of the disease.

Human neutrophil elastase in temporal (giant cell) arteritis: plasma and immunohistochemical studies

OBJECTIVE

Few enzymes are able to attack the internal elastic lamina, which is destroyed in temporal arteritis (TA). Because human neutrophil elastase (HNE) is one of these, its role in the pathogenesis of TA was examined in patients undergoing temporal artery biopsy for suspected TA.

METHODS

Over a 6 month period, 33 patients undergoing temporal artery biopsy were prospectively included in the study. TA was diagnosed in 15 patients; 9 of them had positive temporal artery biopsy. The other 18 patients made up the non-TA group. Nineteen healthy age matched subjects (mean age 74 +/- 9 yrs) served as controls. Levels of plasma HNE bound to alpha1-antitrypsin (pHNE-alpha1AT) were measured by ELISA. The presence of HNE in the temporal artery wall of 7 TA and 7 non-TA patients was evaluated immunohistochemically.

RESULTS

Age, neutrophil counts, and erythrocyte sedimentation rates were similar in TA and non-TA patients. The mean pHNE-alpha1AT concentration in the TA group (84 +/- 20 microg/l) was significantly higher (p < 0.001) than in the non-TA group (51 +/- 26 microg/l) or in healthy controls (52 +/- 23 microg/l). The diagnostic sensitivity of pHNE-alpha1AT > 50 microg/l was 100%. Immunohistochemistry detected no HNE within the temporal artery wall of any patient.

CONCLUSION

High levels of pHNE-alpha1AT were associated with TA. Our preliminary results indicate this could be a diagnostic marker for TA. Further studies are needed to confirm its reliability. Because HNE was not detected locally, no conclusions can be drawn as to its pathogenic role in TA.

Imbalanced "memory" T lymphocyte subsets and analysis of dendritic cell precursors in the peripheral blood of adult patients with Langerhans cell histiocytosis

OBJECTIVES

To investigate the phenotype of lymphocytes and dendritic cell precursors in the peripheral blood of adult patients with histiocytosis X.

METHODS

Data were obtained on patients with histiocytosis X treated in La Pitié-Salpetrière Hospital. Peripheral blood mononuclear cells from 10 patients (4 with unifocal and 6 with disseminated disease) were studied by flow cytometry. A method was set up to detect circulating Langerhans cells, dendritic cells and their precursors.

RESULTS

An abnormal repartition of "memory" T lymphocyte subsets was observed, with a significant decrease of CD4CD45RO and CD8CD45RO and a reciprocal increase of CD4CD45RA "naive" cells, while CD4+ cells displaying the accessory molecule CD28 were decreased in some patients. These abnormalities disappeared in vitro after triggering of the CD3 and CD28 molecules in the absence of antigen presenting cells, hence demonstrating that there was no constitutive defect in the capacity of CD4+ and CD8+ T cells to convert from the CD45RO- to the CD45RO+ isoform. Langerhans cells were undetectable in the peripheral blood, and dendritic cells and their precursors were present in normal proportions (0.5 +/- 0.2% and 2.8 +/- 1.2%, respectively), but the latter were more numerous (4% and 6% of the PBMC) in the two patients with the more severe form of the disease.

CONCLUSIONS

We found in these patients some T lymphocyte phenotype abnormalities which suggest alterations in antigen-driven activation processes. The number of dendritic precursor cells was not consistently elevated in the peripheral blood from histiocytosis X patients.

Effects of lamivudine on replication of hepatitis B virus in HIV-infected men

BACKGROUND

Therapy for hepatitis B virus (HBV) infection is still unsatisfactory, particularly in patients who are co-infected with the human immunodeficiency virus (HIV). Lamivudine, a retroviral inhibitor, has been shown to have activity against HBV replication in vitro, in animal models, and in studies of immunocompetent persons.

OBJECTIVE

To assess the efficacy of lamivudine in inhibiting HBV replication during a 12-month period in patients with both HBV and HIV infection.

DESIGN

Prospective, open study.

SETTING

University hospital.

PATIENTS

40 consecutive patients (39 men and 1 woman) infected with both HIV and HBV. All had progressive HIV disease; were refractory to or unable to tolerate therapies other than lamivudine; and received lamlvudine, 600 mg/d or 600 mg/d followed by 300 mg/d, as therapy for HIV disease.

MEASUREMENTS

Serum concentrations of HBV DNA were assessed every 2 months by using molecular hybridization. Polymerase chain reaction (PCR) for HBV DNA was done at baseline and was done at months 2, 6, and 12 only if the HBV DNA concentration was less than 5 pg/mL.

RESULTS

Two groups were retrospectively identified at baseline: patients with high HBV replication (serum HBV DNA concentrations > 5 pg/mL) (n = 30) and patients with low HBV replication (serum HBV DNA concentrations < 5 pg/mL) (n = 10). After 12 months of treatment, 26 of 27 patients (96.3% [95% Cl, 81% to 99.9%]) who had had high HBV replication at baseline had serum HBV DNA concentrations less than 5 pg/mL. However, PCR could still detect HBV DNA in serum in 11.5% (Cl, 2% to 30%) of these patients. Among patients who had had low HBV replication at baseline, the results of PCR for serum HBV DNA became negative in the 6 patients who had had a positive result on PCR at baseline. No serious adverse events occurred during treatment.

CONCLUSION

Although this study was not a randomized, blinded trial, it suggests that lamivudine is active against.

Mechanisms of lysis by activated cytotoxic cells expressing perforin and granzyme-B genes and the protein TIA-1 in muscle biopsies of myositis

OBJECTIVE

Polymyositis (PM) and cermatomyositis (DM) are inflammatory muscle diseases of autoimmune origin. A chronic mononuclear cell infiltrate is always present around PM and DM muscle damage. In PM, the predominant cells are activated cytotoxic cells, natural killer, and CD8+ T lymphocytes. Cytotoxic cells can kill the target cells via 2 mechanisms. Both pathways induce target cell death by releasing the molecules (granule exocytosis) perforin (PF), which attacks the target cell membrane and causes cell death by necrosis, and TIA-1 protein and granzyme-B (GZB), possibly responsible for apoptosis. We studied the mechanisms of lysis in muscle biopsies of myositis.

METHODS

We used a panel of monoclonal antibodies to determine the phenotypes of reactive lymphocyte subsets, in situ hybridization to study the expression of PF and GZB genes, and immunohistochemistry to evaluate TIA-1 protein production in muscle biopsies from 14 patients with myositis (11 PM/3 DM). Results were compared to those obtained from muscle biopsies of 12 control patients with muscle weakness, including patients with muscle dystrophy and vasculitis, but without myositis.

RESULTS

Abundant CD8+ cells, especially in endomysial sites in PM, formed the predominant phenotype. The predominant mononuclear cells observed in DM were CD4+ T cells and CD22+ B lymphocytes, in perivascular sites. The GZB and PF genes and the TIA-1 protein were expressed simultaneously in muscle samples from patients with myositis. GZB, PF, and TIA-1 positive cells were predominantly located in endomysial sites of PM, in the nonnecrotic muscle fibers. In DM, these positive cells were rare.

CONCLUSION

In myositis, especially PM, cytotoxic cells may cause muscle damage and muscle cell necrosis and/or apoptosis by releasing several proteins (PF, GZB, and TIA-1 proteins) responsible for the lysis of these stimulating target cells. Some drugs (prednisone and cyclosporine) inhibit the release of GZB and PF. Their efficacy may be due in part to this inhibitory effect.

Plasma and skin suction-blister-fluid pharmacokinetics and time course of the effects of oral mizolastine

OBJECTIVE

To investigate plasma and skin suction-blister-fluid pharmacokinetics of oral mizolastine in order to determine whether the drug concentration in the fluid of suction-induced skin blisters could better predict the antihistamine activity than the plasma concentration.

SETTING

Department of Internal Medicine, Université Paris 6.

SUBJECTS

Ten healthy male volunteers.

METHODS

The volunteers (mean age 26.8 years, mean weight 75.8 kg) received a single 10-mg oral dose of mizolastine at 1000 hours. The pharmacokinetic study included 11 plasma and 9 blister fluid samples and blister epidermal-roof specimens. Mizolastine was assayed by high-performance liquid chromatography (HPLC). Each volunteer also received nine intradermal injections of 5 micrograms histamine. Antihistamine activity was assessed as the post-treatment percentages of changes in the histamine-induced relative wheal and flare areas versus baseline.

RESULTS

Mizolastine mean Cmax (SD) and median tmax were, respectively, 380 ng.ml-1 and 0.8 h in plasma, and 21.8 ng.ml-1 and 10 h in blister fluid. Mizolastine could not be quantified in the epidermis. The maximal histamine-induced relative flare inhibition was 72.5% and was attained at the median time of 3 h post-dosing and therefore was delayed by 2.2 h with respect to the plasma tmax. Mean relative wheal inhibition, although lower, showed the same time profile. A direct relationship could not be found between drug concentrations in blister fluid and antihistamine activity. Simulated concentrations in the peripheral compartment better explain the maximum inhibition effect on flare, observed 3 h post-dosing, with a flatter hysteresis loop obtained when plotting relative flare inhibition versus plasma or blister-fluid drug concentrations.

CONCLUSION

The mizolastine concentrations in the skin suction-blister fluid were not predictive of the antihistamine activity.