Christine M. Durand

Improved management of invasive pulmonary aspergillosis in neutropenic patients using early thoracic computed tomographic scan and surgery.

PURPOSE The prognosis of invasive pulmonary aspergillosis (IPA) occurring in neutropenic patients remains poor. We studied whether new strategies for early diagnosis could improve outcome in these patients. PATIENTS AND METHODS Twenty-three histologically proven and 14 highly probable IPAs in 37 hematologic patients (neutropenic in 36) were analyzed retrospectively. RESULTS The most frequent clinical signs associated with IPA were cough (92%), chest pain (76%), and hemoptysis (54%). Bronchoalveolar lavage (BAL) was positive in 22 of 32 cases. Aspergillus antigen test was positive in 83% of cases when tested on BAL fluid. Since October 1991, early thoracic computed tomographic (CT) scans were systematically performed in febrile neutropenic patients with pulmonary x-ray infiltrates. This approach allowed us to recognize suggestive CT halo signs in 92% of patients, compared with 13% before this date, and the mean time to IPA diagnosis was reduced dramatically from 7 to 1.9 days. Among 36 assessable patients, 10 failed to respond (amphotericin B [AmB] plus fluorocytosyne, n = 2; itraconazole + AmB, n = 8) and died of aspergillosis. Twenty-six patients were cured or improved by antifungal treatment (itraconazole with or without AmB, n = 22; voriconazole, n = 4). In 15 of 16 cases, surgical resection was combined successfully with medical treatment. Achievement of hematologic response, early diagnosis, unilateral pulmonary involvement, and highest level of fibrinogen value < 9 g/L were associated with better outcome. CONCLUSION In febrile neutropenic patients, systematic CT scan allows earlier diagnosis of IPA. Early antifungal treatment, combined with surgical resection if necessary, improves IPA prognosis dramatically in these patients.

Stimulation of HIV-1-Specific Cytolytic T Lymphocytes Facilitates Elimination of Latent Viral Reservoir after Virus Reactivation

Highly active antiretroviral therapy (HAART) suppresses HIV-1 replication but cannot eliminate the virus because HIV-1 establishes latent infection. Interruption of HAART leads to a rapid rebound of viremia, so life-long treatment is required. Efforts to purge the latent reservoir have focused on reactivating latent proviruses without inducing global T cell activation. However, the killing of the infected cells after virus reactivation, which is essential for elimination of the reservoir, has not been assessed. Here we show that after reversal of latency in an in vitro model, infected resting CD4(+) T cells survived despite viral cytopathic effects, even in the presence of autologous cytolytic T lymphocytes (CTLs) from most patients on HAART. Antigen-specific stimulation of patient CTLs led to efficient killing of infected cells. These results demonstrate that stimulating HIV-1-specific CTLs prior to reactivating latent HIV-1 may be essential for successful eradication efforts and should be considered in future clinical trials.

Imaging findings in acute invasive pulmonary aspergillosis: clinical significance of the halo sign.

BACKGROUND Computed tomography (CT) of the chest may be used to identify the halo sign, a macronodule surrounded by a perimeter of ground-glass opacity, which is an early sign of invasive pulmonary aspergillosis (IPA). This study analyzed chest CT findings at presentation from a large series of patients with IPA, to assess the prevalence of these imaging findings and to evaluate the clinical utility of the halo sign for early identification of this potentially life-threatening infection. METHODS Baseline chest CT imaging findings from 235 patients with IPA who participated in a previously published study were systematically analyzed. To evaluate the clinical utility of the halo sign for the early identification and treatment of IPA, we compared response to treatment and survival after 12 weeks of treatment in 143 patients who presented with a halo sign and in 79 patients with other imaging findings. RESULTS At presentation, most patients (94%) had > or =1 macronodules, and many (61%) also had halo signs. Other imaging findings at presentation, including consolidations (30%), infarct-shaped nodules (27%), cavitary lesions (20%), and air-crescent signs (10%), were less common. Patients presenting with a halo sign had significantly better responses to treatment (52% vs. 29%; P<.001) and greater survival to 84 days (71% vs. 53%; P<.01) than did patients who presented with other imaging findings. CONCLUSIONS Most patients presented with a halo sign and/or a macronodule in this large imaging study of IPA. Initiation of antifungal treatment on the basis of the identification of a halo sign by chest CT is associated with a significantly better response to treatment and improved survival.

New ex vivo approaches distinguish effective and ineffective single agents for reversing HIV-1 latency in vivo

HIV-1 persists in a latent reservoir despite antiretroviral therapy (ART). This reservoir is the major barrier to HIV-1 eradication. Current approaches to purging the latent reservoir involve pharmacologic induction of HIV-1 transcription and subsequent killing of infected cells by cytolytic T lymphocytes (CTLs) or viral cytopathic effects. Agents that reverse latency without activating T cells have been identified using in vitro models of latency. However, their effects on latently infected cells from infected individuals remain largely unknown. Using a new ex vivo assay, we demonstrate that none of the latency-reversing agents (LRAs) tested induced outgrowth of HIV-1 from the latent reservoir of patients on ART. Using a quantitative reverse transcription PCR assay specific for all HIV-1 mRNAs, we demonstrate that LRAs that do not cause T cell activation do not induce substantial increases in intracellular HIV-1 mRNA in patient cells; only the protein kinase C agonist bryostatin-1 caused significant increases. These findings demonstrate that current in vitro models do not fully recapitulate mechanisms governing HIV-1 latency in vivo. Further, our data indicate that non-activating LRAs are unlikely to drive the elimination of the latent reservoir in vivo when administered individually.

Broad CTL response is required to clear latent HIV-1 due to dominance of escape mutations

Despite antiretroviral therapy (ART), human immunodeficiency virus (HIV)-1 persists in a stable latent reservoir, primarily in resting memory CD4+ T cells. This reservoir presents a major barrier to the cure of HIV-1 infection. To purge the reservoir, pharmacological reactivation of latent HIV-1 has been proposed and tested both in vitro and in vivo. A key remaining question is whether virus-specific immune mechanisms, including cytotoxic T lymphocytes (CTLs), can clear infected cells in ART-treated patients after latency is reversed. Here we show that there is a striking all or none pattern for CTL escape mutations in HIV-1 Gag epitopes. Unless ART is started early, the vast majority (>98%) of latent viruses carry CTL escape mutations that render infected cells insensitive to CTLs directed at common epitopes. To solve this problem, we identified CTLs that could recognize epitopes from latent HIV-1 that were unmutated in every chronically infected patient tested. Upon stimulation, these CTLs eliminated target cells infected with autologous virus derived from the latent reservoir, both in vitro and in patient-derived humanized mice. The predominance of CTL-resistant viruses in the latent reservoir poses a major challenge to viral eradication. Our results demonstrate that chronically infected patients retain a broad-spectrum viral-specific CTL response and that appropriate boosting of this response may be required for the elimination of the latent reservoir.

Ex vivo analysis identifies effective HIV-1 latency–reversing drug combinations

Reversal of HIV-1 latency by small molecules is a potential cure strategy. This approach will likely require effective drug combinations to achieve high levels of latency reversal. Using resting CD4+ T cells (rCD4s) from infected individuals, we developed an experimental and theoretical framework to identify effective latency-reversing agent (LRA) combinations. Utilizing ex vivo assays for intracellular HIV-1 mRNA and virion production, we compared 2-drug combinations of leading candidate LRAs and identified multiple combinations that effectively reverse latency. We showed that protein kinase C agonists in combination with bromodomain inhibitor JQ1 or histone deacetylase inhibitors robustly induce HIV-1 transcription and virus production when directly compared with maximum reactivation by T cell activation. Using the Bliss independence model to quantitate combined drug effects, we demonstrated that these combinations synergize to induce HIV-1 transcription. This robust latency reversal occurred without release of proinflammatory cytokines by rCD4s. To extend the clinical utility of our findings, we applied a mathematical model that estimates in vivo changes in plasma HIV-1 RNA from ex vivo measurements of virus production. Our study reconciles diverse findings from previous studies, establishes a quantitative experimental approach to evaluate combinatorial LRA efficacy, and presents a model to predict in vivo responses to LRAs.

Sofosbuvir plus daclatasvir for post-transplant recurrent hepatitis C: Potent antiviral activity but no clinical benefit if treatment is given late

BACKGROUND We evaluated efficacy and safety of sofosbuvir and daclatasvir±ribavirin in liver transplant recipients with severe recurrent hepatitis C. METHODS Patients included in an international compassionate use programme for treatment with sofosbuvir and daclatasvir±ribavirin for 24 weeks were prospectively studied. Serum hepatitis C virus RNA was measured at treatment weeks 4, 12, and 24 and during follow-up at weeks 4, 8, and 12. RESULTS Twelve patients (3 with fibrosing cholestatic hepatitis and 9 with cirrhosis; median model for end-stage liver disease score 20) received sofosbuvir 400mg/day+daclatasvir 60mg/day, and 6 patients (50%) also received ribavirin 200-800mg/day. Nine patients completed 24 weeks of treatment (75%), and all had undetectable hepatitis C virus RNA at week 24; 3 patients died (25%, liver failure, gastrointestinal bleeding and sepsis); 4 patients experienced severe liver disease-related adverse events. Post-treatment hepatitis C virus RNA was available for 5 patients (week 8, n=2; week 4, n=3) and was undetectable in all cases. Mean Child-Pugh score and albumin level improved significantly at week 24. No changes in immunosuppressant doses were needed. CONCLUSION All-oral sofosbuvir plus daclatasvir combination shows high virological efficacy in liver transplant recipients and does not interact with immunosuppressants. All adverse events were unrelated to study drugs. These data strongly suggest that this combination must be initiated before decompensation.

Multi-step inhibition explains HIV-1 protease inhibitor pharmacodynamics and resistance

HIV-1 protease inhibitors (PIs) are among the most effective antiretroviral drugs. They are characterized by highly cooperative dose-response curves that are not explained by current pharmacodynamic theory. An unresolved problem affecting the clinical use of PIs is that patients who fail PI-containing regimens often have virus that lacks protease mutations, in apparent violation of fundamental evolutionary theory. Here, we show that these unresolved issues can be explained through analysis of the effects of PIs on distinct steps in the viral life cycle. We found that PIs do not affect virion release from infected cells but block entry, reverse transcription, and post-reverse transcription steps. The overall dose-response curves could be reconstructed by combining the curves for each step using the Bliss independence principle, showing that independent inhibition of multiple distinct steps in the life cycle generates the highly cooperative dose-response curves that make these drugs uniquely effective. Approximately half of the inhibitory potential of PIs is manifest at the entry step, likely reflecting interactions between the uncleaved Gag and the cytoplasmic tail (CT) of the Env protein. Sequence changes in the CT alone, which are ignored in current clinical tests for PI resistance, conferred PI resistance, providing an explanation for PI failure without resistance.

Interferon-free therapy for genotype 1 hepatitis C in liver transplant recipients: Real-world experience from the hepatitis C therapeutic registry and research network.

Recurrent infection with the hepatitis C virus (HCV) after liver transplantation (LT) is associated with decreased graft and patient survival. Achieving sustained virological response (SVR) with antiviral therapy improves survival. Because interferon (IFN)‐based therapy has limited efficacy and is poorly tolerated, there has been rapid transition to IFN‐free direct‐acting antiviral (DAA) regimens. This article describes the experience with DAAs in the treatment of posttransplant genotype (GT) 1 HCV from a consortium of community and academic centers (Hepatitis C Therapeutic Registry and Research Network [HCV‐TARGET]). Twenty‐one of the 54 centers contributing to the HCV‐TARGET consortium participated in this study. Enrollment criteria included positive posttransplant HCV RNA before treatment, HCV GT 1, and documentation of use of a simeprevir (SMV)/sofosbuvir (SOF) containing DAA regimen. Safety and efficacy were assessed. SVR was defined as undetectable HCV RNA 64 days or later after cessation of treatment. A total of 162 patients enrolled in HCV‐TARGET started treatment with SMV+SOF with or without ribavirin (RBV) following LT. The study population included 151 patients treated with these regimens for whom outcomes and safety data were available. The majority of the 151 patients were treated with SOF and SMV alone (n = 119; 79%) or with RBV (n = 32; 21%), The duration of therapy was 12 weeks for most patients, although 15 patients received 24 weeks of treatment. Of all patients receiving SOF/SMV with or without RBV, 133/151 (88%) achieved sustained virological response at 12 weeks after therapy and 11 relapsed (7%). One patient had virological breakthrough (n = 1), and 6 patients were lost to posttreatment follow‐up. Serious adverse events occurred in 11.9%; 3 patients (all cirrhotic) died due to aspiration pneumonia, suicide, and multiorgan failure. One experienced LT rejection. IFN‐free DAA treatment represents a major improvement over prior IFN‐based therapy. Broader application of these and other emerging DAA regimens in the treatment of posttransplant hepatitis C is warranted. Liver Transpl 22:24‐33, 2016.

HIV-1 DNA Is Detected in Bone Marrow Populations Containing CD4+ T Cells but Is not Found in Purified CD34+ Hematopoietic Progenitor Cells in Most Patients on Antiretroviral Therapy

Identifying cellular reservoirs of human immunodeficiency virus type 1 (HIV-1) in patients on antiretroviral therapy (ART) is critical to finding a cure for HIV-1. In addition to resting CD4(+) T cells, CD34(+) hematopoietic progenitor cells have been proposed as another reservoir. We obtained bone marrow aspirates from 11 patients on ART who had undetectable plasma HIV-1 RNA. HIV-1 DNA was detected in CD4(+) T cells from peripheral blood in all patients and from bone marrow cellular fractions containing T cells in most patients. We did not find HIV-1 DNA in highly purified CD34(+) populations using either a sensitive real-time polymerase chain reaction assay or a coculture assay for replication-competent HIV-1.