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Background: Due to the low number of individuals with HIV-2, no randomised trials of HIV-2 treatment have ever been done. We hypothesised that a non-comparative study describing the outcomes of several antiretroviral therapy (ART) regimens in parallel groups would improve understanding of how differences between HIV-1 and HIV-2 might lead to different therapeutic approaches., Methods: This pilot, phase 2, non-comparative, open-label, randomised controlled trial was done in Burkina Faso, Côte d'Ivoire, Senegal, and Togo. Adults with HIV-2 who were ART naive with CD4 counts of 200 cells per μL or greater were randomly assigned 1:1:1 to one of three treatment groups. A computer-generated sequentially numbered block randomisation list stratified by country was used for online allocation to the next available treatment group. In all groups, tenofovir disoproxil fumarate (henceforth tenofovir) was dosed at 245 mg once daily with either emtricitabine at 200 mg once daily or lamivudine at 300 mg once daily. The triple nucleoside reverse transcriptase inhibitor (NRTI) group received zidovudine at 250 mg twice daily. The ritonavir-boosted lopinavir group received lopinavir at 400 mg twice daily boosted with ritonavir at 100 mg twice daily. The raltegravir group received raltegravir at 400 mg twice daily. The primary outcome was the rate of treatment success at week 96, defined as an absence of serious morbidity event during follow-up, plasma HIV-2 RNA less than 50 copies per mL at week 96, and a substantial increase in CD4 cells between baseline and week 96. This trial is registered at ClinicalTrials.gov, NCT02150993, and is closed to new participants., Findings: Between Jan 26, 2016, and June 29, 2017, 210 participants were randomly assigned to treatment groups. Five participants died during the 96 weeks of follow-up (triple NRTI group, n=2; ritonavir-boosted lopinavir group, n=2; and raltegravir group, n=1), eight had a serious morbidity event (triple NRTI group, n=4; ritonavir-boosted lopinavir group, n=3; and raltegravir group, n=1), 17 had plasma HIV-2 RNA of 50 copies per mL or greater at least once (triple NRTI group, n=11; ritonavir-boosted lopinavir group, n=4; and raltegravir group, n=2), 32 (all in the triple NRTI group) switched to another ART regimen, and 18 permanently discontinued ART (triple NRTI group, n=5; ritonavir-boosted lopinavir group, n=7; and raltegravir group, n=6). The Data Safety Monitoring Board recommended premature termination of the triple NRTI regimen for safety reasons. The overall treatment success rate was 57% (95% CI 47-66) in the ritonavir-boosted lopinavir group and 59% (49-68) in the raltegravir group., Interpretation: The raltegravir and ritonavir-boosted lopinavir regimens were efficient and safe in adults with HIV-2. Both regimens could be compared in future phase 3 trials. The results of this pilot study suggest a trend towards better virological and immunological efficacy in the raltegravir-based regimen., Funding: ANRS MIE., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Access to Hepatis C treatment in Sub-Saharan Africa is a clinical, public health and ethical concern. The multi-country open-label trial TAC ANRS 12311 allowed assessing the feasibility, safety, efficacy of a specific care model of HCV treatment and retreatment in patients with hepatitis C in Sub Saharan Africa. Between November 2015 and March 2017, with follow-up until mid 2019, treatment-naïve patients with HCV without decompensated cirrhosis or liver cancer were recruited to receive 12 week-treatment with either sofosbuvir + ribavirin (HCV genotype 2) or sofosbuvir + ledipasvir (genotype 1 or 4) and retreatment with sofosbuvir + velpatasvir + voxilaprevir in case of virological failure. The primary outcome was sustained virological response at 12 weeks after end of treatment (SVR12). Secondary outcomes included treatment adherence, safety and SVR12 in patients who were retreated due to non-response to first-line treatment. The model of care relied on both viral load assessment and educational sessions to increase patient awareness, adherence and health literacy. The study recruited 120 participants, 36 HIV-co-infected, and 14 cirrhotic. Only one patient discontinued treatment because of return to home country. Neither death nor severe adverse event occurred. SVR12 was reached in 107 patients (89%): (90%) in genotype 1 or 2, and 88% in GT-4. All retreated patients (n = 13) reached SVR12. HCV treatment is highly acceptable, safe and effective under this model of care. Implementation research is now needed to scale up point-of-care HCV testing and SVR assessment, along with community involvement in patient education, to achieve HCV elimination in Sub-Saharan Africa., (© 2024. The Author(s).)

Background: Data on HIV-1 controllers in Africa are scarce. We report the proportion of HIV-1 controllers in a group of adults prospectively monitored with frequent viral load measurements as part of a clinical trial in West Africa., Methods: For the Temprano trial, antiretroviral therapy (ART)-naive HIV-1 infected adults with no criteria for starting ART were randomized to start ART immediately or defer ART until the WHO starting criteria were met. Plasma viral load was measured every 6 months. The trial follow-up was 30 months. We considered all Temprano participants randomized to defer ART. Patients with all semestrial viral <2000 copies/ml and still off ART at month 30 were defined as HIV-1 controllers. Controllers with all viral loads <50 copies/ml were defined as elite controllers, the rest as viremic controllers., Results: Of the 1023 HIV-1-infected adults randomized in the Temprano deferred-ART group, 18 (1.8%) met the criteria for classification as HIV controllers, of whom seven (0.7%) were elite controllers and 11 (1.1%) viremic controllers. The HIV-1 controllers had low peripheral blood mononuclear cell HIV-1 DNA and low inflammatory marker levels. They maintained high CD4+ cell count and percentages and had a low morbidity rate., Discussion: HIV controllers exist in Africa at a proportion close to that reported elsewhere. They represent a small fraction of all HIV-1-infected patients but raise important questions. Further studies should assess whether starting ART might represent more risk than benefit for some controllers, and where it does, how to identify these patients before they start ART., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc.)

Background: Asymptomatic HIV-infected people who start ART early may feel less motivated and neglect compliance. This might promote the emergence of resistance., Methods: In the Temprano trial, ART-naive HIV-infected adults with high CD4 counts were randomly assigned to start ART immediately (immediate group) or defer ART until the WHO criteria were met (deferred group). All participants were monitored for 30 months. Those in the deferred group who started ART were monitored for longer, until they had completed 30 months on ART. We compared the rate of virological failure and drug resistance between the immediate and deferred groups 30 months after ART initiation., Results: Of the 2056 participants in Temprano, 1033 were assigned to start ART immediately and 1023 to defer ART. Of the latter, 488 started ART during trial follow-up. Patients in the deferred group who started ART had a lower median CD4 count (280 versus 465 cells/mm3) and a higher median plasma HIV-1 RNA (5.1 versus 4.7 log10 copies/mL) at baseline. During follow-up, participants in both groups had similar antiretroviral drug exposure. Thirty months after ART initiation, patients in the deferred group had a higher rate of virological failure (35.3% versus 29.9%, P = 0.04) and a lower genotypic susceptibility score (P = 0.04)., Conclusions: Starting ART early decreases the risk of virological failure and drug resistance in the medium term. This benefit is of particular importance in countries where access to viral load monitoring and the number of antiretroviral drug lines is limited., (© The Author(s) 2021. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background: Several biomarkers of inflammation and coagulation were reported to be associated with HIV disease progression in different settings. In this article, we report the association between 11 biomarkers and medium-term mortality in HIV-infected West African adults., Methods: In Temprano ANRS 12136, antiretroviral therapy (ART)-naive HIV-infected adults with high CD4 counts were randomly assigned either to start ART immediately or defer ART until the World Health Organization criteria were met. Participants who completed the 30-month trial follow-up were invited to participate in a posttrial phase. The posttrial phase end point was all-cause death. We used multivariate Cox proportional models to analyze the association between baseline plasma biomarkers [IL-1ra, IL-6, soluble vascular cell adhesion molecule 1 (sVCAM-1), sCD14, D-dimer, fibrinogen, IP-10, sCD163, albumin, high-sensitivity C-reactive protein, and 16S rDNA] and all-cause death in the Temprano participants randomized to defer ART., Results: Four hundred seventy-seven patients (median age 35 years, 78% women, and median CD4 count: 379 cells/mm) were randomly assigned to defer starting ART until the World Health Organization criteria were met. The participants were followed for 2646 person-years (median 5.8 years). In the follow-up, 89% of participants started ART and 30 died. In the multivariate analysis adjusted for the study center, sex, baseline CD4 count, isoniazid preventive therapy, plasma HIV-1 RNA, peripheral blood mononuclear cell HIV-1 DNA, and ART, the risk of death was significantly associated with baseline sVCAM-1 (≥1458 vs. <1458: adjusted hazard ratio 2.57, 95% confidence interval: 1.13 to 5.82) and sCD14 (≥2187 vs. <2187: adjusted hazard ratio 2.79, interquartile range 1.29-6.02) levels., Conclusions: In these sub-Saharan African adults with high CD4 counts, pre-ART plasma sVCAM-1 and sCD14 levels were independently associated with mortality.

Background: The decision about whether to switch to third-line antiretroviral therapy (ART) in patients with treatment failure on second-line therapy is difficult in settings with little access to genotypic resistance testing. In this study, we used a standardised algorithm including a wide range of adherence-enhancing interventions followed by a new viral load measurement to decide whether to switch to third-line therapy in this situation. The decision, made on the basis of effectiveness of the adherence reinforcement to drive viral resuppression, did not use genotypic resistance testing., Methods: In this prospective cohort study, adults in four west African countries with treatment failure of a boosted protease inhibitor ART regimen were offered nine adherence reinforcement interventions, and followed up for 64 weeks. We measured viral load at week 12 and used the results to decide ART treatment at week 16: if successful resuppression (plasma HIV-1 RNA <400 copies per mL or had decreased by ≥2 log 10 copies per mL compared with baseline), patients continued the same second-line regimen; otherwise they switched to a third-line regimen based on ritonavir-boosted darunavir and raltegravir. The primary endpoint was virological success at week 64 (plasma HIV-1 RNA <50 copies per mL). After study termination we did genotypic resistance testing on frozen plasma samples collected at baseline, and retrospectively determined the appropriateness of the week 16 decision on the basis of the baseline genotypic susceptibility score., Findings: Between March 28, 2013, and May 11, 2015, of the 198 eligible participants, five died before week 16. Of the 193 remaining, 130 (67%) reached viral resuppression and continued with second-line ART, and 63 (33%) switched to third-line ART at week 16. Post-study genotypic resistance testing showed that the baseline genotypic susceptibility score was calculable in 166 patients, of whom 57 (34%) had a score less than 2. We retrospectively concluded that the week 16 decision was appropriate in 145 (75%) patients. At week 64, four patients (2%) were lost to follow-up, ten (5%) had died, and 101 (52%) had a viral load less than 50 copies per mL., Interpretation: Poor adherence is the first problem to tackle in patients for whom second-line ART is failing when resistance tests are not routinely available and is effectively a manageable problem. Lack of access to genotypic resistance testing should not be an obstacle to the prescription of third-line ART in patients who do not achieve viral resuppression after adherence reinforcement., Funding: French Agency for Research on AIDS and Viral Hepatitis., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: Hepatitis B virus (HBV) and human immunodeficiency virus (HIV) share common risk factors. The parallel description of their frequency over time may help capture their similarities and differences., Methods: Using data from the National Transfusion Center of Abidjan, we estimated the following over a 20-year period: (1) the prevalence of HIV and hepatitis B surface antigen (HBsAg) positivity at first contact; and (2) the incidence of HIV and HBsAg seroconversion in negative first-time blood donors., Results: Between 1992 and 2012, 422319 donors (men [M] = 74%) provided 1063825 blood donations. For first-time donors, HIV prevalence decreased from 7.1% (M = 5.9%, women [W] =11.0%) in 1992-1994 to 1.1% (M = 0.8%, W = 2.0%) in 2010-2012. Prevalence of HBsAg positivity remained stable at 10.8% (M = 11.7%, W = 7.3%) in 1992-1994 to 11.1% (M = 12.5%, W = 7.1%) in 2010-2012. Among regular donors (N = 129256), the incidence of becoming HIV or HBsAg positive, respectively, decreased from 4.9 per 100 (M = 4.5, W = 8.6) and 7.3 per 100 person-years (M = 7.8, W = 2.3) in 1992-1994 to 0.07 (M = 0.06, W = 0.11) and 0.2 per 100 person-years (M = 0.2, W = 0.2) in 2010-2012., Conclusions: Human immunodeficiency virus prevalence and incidence decreased dramatically over time, whereas HBV prevalence remained stable. Incidence of HBsAg seroconversion, although decreasing, still reached unexpected levels, suggesting that the risk of HBV infection in adults may be higher than expected. Hepatitis B surface antigen-negative blood-donors should be offered HBV vaccination.

Setting: TEMPRANO was a multicentre, open-label trial in which human immunodeficiency virus (HIV) infected adults with high CD4 counts were randomised into early or deferred antiretroviral therapy (ART) arms with or without 6-month isoniazid preventive therapy (IPT) in a setting where the World Health Organization (WHO) recommends IPT in HIV-infected patients. Despite the WHO recommendation, IPT coverage remains low due to fear of the presence of undiagnosed active TB before prescribing IPT, and the related risk of drug resistance., Objective: To report the frequency of undiagnosed TB in patients enrolled for IPT and describe the results of a 1-month buffer period to avoid prescribing IPT for active TB cases., Design: Patients were screened using a clinical algorithm and chest X-ray at Day 0 and started on isoniazid at Month 1 if no sign/symptom suggestive of TB appeared between Day 0 and Month 1., Results: Of 1030 patients randomised into IPT arms. 10% never started IPT at Month 1. Of these, 23 had active TB, including 16 with prevalent TB. Among the 927 patients who started IPT, 6 had active TB, including 1 with prevalent TB. Only 1 patient with active TB received IPT due to the 1-month buffer period between Day 0 and IPT initiation., Conclusion: In this study, 1.6% of adults considered free of active TB based on clinical screening at pre-inclusion actually had active TB.

Background: In sub-Saharan Africa, the burden of human immunodeficiency virus (HIV)-associated tuberculosis is high. We conducted a trial with a 2-by-2 factorial design to assess the benefits of early antiretroviral therapy (ART), 6-month isoniazid preventive therapy (IPT), or both among HIV-infected adults with high CD4+ cell counts in Ivory Coast., Methods: We included participants who had HIV type 1 infection and a CD4+ count of less than 800 cells per cubic millimeter and who met no criteria for starting ART according to World Health Organization (WHO) guidelines. Participants were randomly assigned to one of four treatment groups: deferred ART (ART initiation according to WHO criteria), deferred ART plus IPT, early ART (immediate ART initiation), or early ART plus IPT. The primary end point was a composite of diseases included in the case definition of the acquired immunodeficiency syndrome (AIDS), non-AIDS-defining cancer, non-AIDS-defining invasive bacterial disease, or death from any cause at 30 months. We used Cox proportional models to compare outcomes between the deferred-ART and early-ART strategies and between the IPT and no-IPT strategies., Results: A total of 2056 patients (41% with a baseline CD4+ count of ≥500 cells per cubic millimeter) were followed for 4757 patient-years. A total of 204 primary end-point events were observed (3.8 events per 100 person-years; 95% confidence interval [CI], 3.3 to 4.4), including 68 in patients with a baseline CD4+ count of at least 500 cells per cubic millimeter (3.2 events per 100 person-years; 95% CI, 2.4 to 4.0). Tuberculosis and invasive bacterial diseases accounted for 42% and 27% of primary end-point events, respectively. The risk of death or severe HIV-related illness was lower with early ART than with deferred ART (adjusted hazard ratio, 0.56; 95% CI, 0.41 to 0.76; adjusted hazard ratio among patients with a baseline CD4+ count of ≥500 cells per cubic millimeter, 0.56; 95% CI, 0.33 to 0.94) and lower with IPT than with no IPT (adjusted hazard ratio, 0.65; 95% CI, 0.48 to 0.88; adjusted hazard ratio among patients with a baseline CD4+ count of ≥500 cells per cubic millimeter, 0.61; 95% CI, 0.36 to 1.01). The 30-month probability of grade 3 or 4 adverse events did not differ significantly among the strategies., Conclusions: In this African country, immediate ART and 6 months of IPT independently led to lower rates of severe illness than did deferred ART and no IPT, both overall and among patients with CD4+ counts of at least 500 cells per cubic millimeter. (Funded by the French National Agency for Research on AIDS and Viral Hepatitis; TEMPRANO ANRS 12136 ClinicalTrials.gov number, NCT00495651.).

Background: In HIV-HBV-coinfected patients from sub-Saharan Africa, incidence of antiviral resistant HBV-mutations after initiating long-term antiretroviral therapy (ART) has only been evaluated in limited patient populations., Methods: In this nested, prospective cohort study from two randomized controlled trials in Côte d'Ivoire, 168 ART-naive HIV-HBV-coinfected patients, starting lamivudine (LAM, n=82) or tenofovir/emtricitabine (TDF/FTC, n=86) containing ART were included. HBV DNA viral load (VL) was quantified using an in-house assay (detection limit: <12 copies/ml) while pol and preS/S regions of positive samples were sequenced., Results: At ART-initiation, 39 (23.2%) were hepatitis B e antigen-positive, 53 (31.5%) had alanine or aspartate aminotransferase levels >40 IU/ml and 98/100 (98.0%) harboured genotype E. Among the 127 (75.6%) patients with detectable baseline HBV VL (median 4.27 log10 copies/ml, IQR 3.14-7.64), cumulative percentage achieving undetectable HBV DNA was 74.2% for patients undergoing LAM-containing ART and 94.2% for TDF/FTC-containing ART after a median 35.5 months (IQR 24.3-36.5). No baseline antiviral resistance mutations were observed. Among 28/127 (22.1%) patients with low-level persistent viraemia (last HBV VL: between 12 to <10(5) copies/ml), no incident amino acid changes associated with antiviral resistance were observed. Among 11/127 (8.7%) patients with high-level persistent viraemia (last HBV VL: ≥10(5) copies/ml), only two harboured incident LAM-resistance mutations at positions rtV173L+rtL180M+rtM204V with no patient exhibiting TDF/FTC-resistance. Two patients had transaminase flares >120 IU/ml (incidence rate =0.5/100 person-years)., Conclusions: Antiviral resistance, particularly to LAM, was remarkably rare in this cohort of HIV-HBV-coinfected patients. Further research is needed to determine which coinfected populations might benefit from LAM-containing ART with low risk of resistance.

Introduction: Whether early antiretroviral therapy (ART) initiation could impact sexual risk behaviours remains to be documented. We aimed to investigate changes in sexual behaviours within the 24 months following an early versus standard ART initiation in HIV-positive adults with high CD4 counts., Methods: We used data from a prospective behavioural study nested in a randomized controlled trial of early ART (Temprano-ANRS12136). Time trends in sexual behaviours from enrolment in the trial (M0) to 12-month (M12) and 24-month (M24) visits were measured and compared, using Generalized Estimating Equations models, between participants randomly assigned either to initiate ART immediately (early ART) or to defer ART initiation until on-going WHO starting criteria are met (standard ART). Indicators of sexual behaviours included 1) sexual activity in the past year, 2) multiple partnership in the past year, 3) unprotected sex at last intercourse and 4) risky sex (i.e. unprotected sex with a partner of HIV negative/unknown status) at last intercourse., Results: Analyses included 1952 participants (975 with early ART and 977 with standard ART; overall median baseline CD4 count: 469/mm(3)). Among participants with early ART, significant decreases were found between M0 and M24 in sexual activity (Odds Ratio [OR] 0.72, 95% Confidence Interval [95% CI] 0.57-0.92), multiple partnership (OR 0.57, 95% CI 0.41-0.79), unprotected sex (OR 0.59, 95% CI 0.47-0.75) and risky sex (OR 0.58, 95% CI 0.45-0.76). Among participants with standard ART, sexual behaviours showed similar trends over time. These decreases mostly occurred within the 12 months following enrolment in the trial in both groups and prior to ART initiation in participants with standard ART. For unprotected sex and risky sex, decreases were or tended to be more pronounced among patients reporting that their last sexual partner was non-cohabiting., Conclusions: In these sub-Saharan adults with high CD4 counts, entry into HIV care, rather than ART initiation, resulted in decreased sexual activity and risky sexual behaviours. We did not observe any evidence of a risk compensation phenomenon associated with early ART initiation. These results illustrate the potential behavioural preventive effect of early entry into care, which goes hand in hand with early ART initiation.

To evaluate the implication of WHO guidelines for serodiscordant couples, we interviewed HIV-infected adults on their partner's serostatus. We found that 12% with more than 500 CD4+ cells/μl should be recommended antiretroviral treatment (ART) because their partner was seronegative; 24% could be recommended not to start ART because their partner was seropositive; and 64% could not be given any recommendation regarding ART early initiation because they had either no stable partnership (30%) or were in a stable partnership with a partner whose status they were not aware of (34%).

The purpose of this study was to determine the optimal route of infection and the optimal sampling sites for the recovery of M. hyopneumoniae, the etiological agent of enzootic porcine pneumonia. Virulence of two strains, BQ 14 and 116, isolated in France in 1975 and 2003, respectively, was also compared. Groups of specific pathogen free piglets were experimentally infected by the intratracheal or intranasal route. One non-inoculated pig was placed in each group of infected pigs to study direct transmission. Two groups were kept uninfected. Coughing was recorded daily. Blood samples, nasal, tonsillar and tracheal swabs and tracheobronchiolar washings were collected weekly. Pigs were killed 27-37 days post-infection. Lung lesions were scored and swabs were collected from nasal cavities, tonsils, trachea, lung, liver and spleen. All the samples, collected from live and dead pigs, were cultured for M. hyopneumoniae recovery. Results showed that both experimentally infected pigs and contact pigs developed enzootic pneumonia, whatever the route of infection and the strain tested. Direct contact transmission occurred quickly. No difference between the two routes of infection or between the two strains tested was evidenced, but high individual variations were observed between pigs. Tracheal swabs and tracheobronchiolar washings were the most effective samples to detect M. hyopneumoniae compared to nasal or tonsillar swabs. Our results also suggested that tracheobronchiolar washings could have an influence on the lesion extent observed at necropsy. M. hyopneumoniae could be re-isolated from liver and spleen of experimentally infected pigs and contact pigs.

The ability of Mycoplasma hyopneumoniae to persist despite fluoroquinolone treatments was investigated with pigs. Groups of specific-pathogen-free pigs were experimentally infected with M. hyopneumoniae strain 116 and treated with marbofloxacin at the therapeutic dose (TD) or half of the therapeutic dose (TD/2) for 3 days. Results showed that, despite tissue penetration of marbofloxacin, particularly in the trachea and the tracheal secretions, the treatments did not have any influence on M. hyopneumoniae recovery from tracheal swabs. Mycoplasmas were also isolated from inner organs and tissues such as liver, spleen, kidneys, and bronchial lymph nodes. Recontamination of pigs via environment could not explain mycoplasma persistence after medication, as decontamination of pigs and allocation to a new disinfected environment did not have any significant effect on the phenomenon. A significant decrease in the susceptibility level to marbofloxacin of 12 mycoplasma clones reisolated after the treatments (TD/2 and TD) was observed. Two point mutations were found in the ParC quinolone resistance-determining region (QRDR) of DNA topoisomerase IV (Ser80-->Phe and Asp84-->Asn), and one point mutation was observed just behind the QRDR of ParC (Ala116-->Glu). This is the first time that mutations in a gene coding for topoisomerase IV have been described for M. hyopneumoniae after in vivo marbofloxacin treatments in experimentally infected pigs. However, development of resistance is not sufficient to explain M. hyopneumoniae persistence in vivo since (i) marbofloxacin concentrations were above the marbofloxacin MIC of the wild-type strain and (ii) mycoplasmas reisolated after a single injection of marbofloxacin did not display an increased marbofloxacin MIC.

The ability of Mycoplasma synoviae, an avian pathogen, to persist despite fluoroquinolone treatments was investigated in hens. Groups of Mycoplasma-free hens were experimentally infected with the M. synoviae 317 strain and treated twice with enrofloxacin at the therapeutic dose. The results show that the two treatments did not have any influence on this strain of M. synoviae recovery from tracheal swabs. Mycoplasmas were isolated from tracheal swab cultures, but not from inner organs such as the liver or spleen, suggesting that this strain of M. synoviae was not able to cross the mucosal barrier to disseminate throughout the host. A significant increase of the resistance level to enrofloxacin of five re-isolated mycoplasma clones, was observed after the second treatment. This increase was associated in two clones to a Ser81-->Pro substitution, found in the ParC quinolone-resistance determining region (QRDR) of DNA topoisomerase IV. This is the first time that a mutation in a gene coding for topoisomerase IV is described in M. synoviae after in vivo enrofloxacin treatments in experimentally infected hens.

Purpose: The aim of the work was to investigate the effects of adenovirus(Ad)-mediated IFN gamma gene transfer on human mesothelioma (HM) cell proliferation in vitro and growth in nude mice., Experimental Design: We constructed an E1E3-deleted replication-defective recombinant Ad carrying the human IFN gamma gene (Ad-IFN gamma) and tested its activity in vitro on HM cell lines established in our laboratory and in a nude mice model., Results: In vitro, infection of HM cells with Ad-IFN gamma led to a prolonged production of an active cytokine in the 10 HM cell lines tested and also led to an antiproliferative effect on the HM cells previously demonstrated as responsive to exogenous recombinant human IFN gamma. In nude mice, s.c. inoculation of HM cells from one responsive HM cell line previously infected with Ad-IFN gamma resulted in a delay in tumor development, and injection of Ad-IFN gamma in preestablished tumors restrained tumor development., Conclusions: These results indicate for the first time that HM cells are efficiently transduced by Ad-IFN gamma and produce an active cytokine for several days. IFN gamma produced by gene transfer is shown to have both an antiproliferative effect in vitro and an antitumoral effect in vivo in a nude mice model.