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2.
J Clin Virol ; 169: 105609, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37839137

RESUMO

OBJECTIVE: To assess whether varicella zoster virus (VZV) DNA can be detected in blood before herpes zoster (HZ) rash onset. METHOD: Monocentric retrospective study from January 2019 to March 2023 including patients with HZ and stored blood samples performed during the week preceding the onset of HZ rash. Blood samples were retrospectively analyzed for VZV DNA by quantitative PCR. RESULTS: Among the 138 patients with HZ during the study period, stored blood samples performed during the week preceding the onset of HZ rash were available for 13 of them. Twelve (92 %) patients were immunosuppressed, mostly due to solid organ transplantation (38 %), solid malignancy (31 %) or autoimmune disease (23 %). During the week preceding HZ onset, VZV DNA was detected in blood from 10 (77 %) patients, with a median value of 3.6 log (copies/mL) (IQR 3.3-3.9). At the time of HZ onset, all VZV PCR performed in available blood samples were positive. CONCLUSION: Our findings demonstrates that VZV DNA can be commonly detected in blood from immunocompromised patients during the prodromal phase of HZ. Early screening of VZV DNA in blood from high-risk immunocompromised patients might improve HZ therapeutic management.


Assuntos
Exantema , Herpes Zoster , Humanos , Herpesvirus Humano 3/genética , Estudos Retrospectivos , Herpes Zoster/diagnóstico , Herpes Zoster/tratamento farmacológico , Hospedeiro Imunocomprometido
3.
Leuk Lymphoma ; 64(7): 1295-1303, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37165601

RESUMO

Norovirus (NoV) and Sapovirus (SaV) are potential causative agents of diarrhea after allogeneic HSCT but little is known in this population. We performed a retrospective analysis by RT-PCR of calicivirus (NoV and SaV), Human adenovirus (HAdV), rotavirus (RV), Aichi virus (AiV), enterovirus (EV), human parechovirus (HPeV) and Human bocavirus (HBoV) in the diarrheal stools of patients after allogeneic HSCT. 49/162 patients had positive viral assays: HAdV (17%), EV (7%), NoV (4.3%), RV and HBoV (3.1% each), SaV (1.9%), AiV (1.2%), HPeV (0.6%). Seven patients were positive for NoV and 3 for SaV. Among viruses-positive samples, the frequency of caliciviruses cases was 7% in the 6 months post-HSCT compared to 40% after (p < 0.0001). The median duration of symptom was 0.7 months but 2 cases, occurring more than one year after HSCT, were chronic, undiagnosed and strongly contributed to morbidity. Systematic testing of caliciviruses appears especially useful in late chronic diarrhea.


Assuntos
Gastroenterite , Transplante de Células-Tronco Hematopoéticas , Norovirus , Sapovirus , Humanos , Lactente , Sapovirus/genética , Norovirus/genética , Gastroenterite/diagnóstico , Gastroenterite/epidemiologia , Gastroenterite/etiologia , Estudos Retrospectivos , Diarreia/diagnóstico , Diarreia/etiologia , Diarreia/epidemiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos
4.
J Med Virol ; 94(12): 6122-6126, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35973907

RESUMO

HSV-2 antiviral resistance mainly occurs in immunocompromised patients and especially in HIV-positive individuals receiving long-term antiviral treatment. Those situations can be challenging as few alternatives are available for HSV infection management. To describe clinical and virological significance of two novel potential HSV-2 resistance mutations after treating an obese patient with a pseudotumoral genital HSV-related lesion. Consecutive different antiviral treatments were used: valacyclovir (VACV) then foscarnet (FOS) then topical cidofovir (CDV) and finally imiquimod. Under VACV, genotypic resistance testing revealed a novel mutation within viral thymidine kinase (TK, gene UL23) not previously reported but probably accounting for antiviral resistance: W89G, similar to W88R mutation reported in HSV-1 TK, known to be associated with ACV resistance for HSV-1. Under FOS, while initial mutations were still present, a second genotypic resistance testing performed on persisting lesions showed a novel mutation within viral DNA polymerase (DNA pol, gene UL30): C625R. All three antivirals used in this case are small molecules and pharmacokinetics of VACV, FOS, and CDV have not been evaluated in animals and there are very few studies in human. As small molecules are poorly bound to proteins and distribution volume is increased in obese patients, there is risk of underdosage. This mechanism is suspected to be involved in emergence of resistance mutation and further data is needed to adapt, closely to patient profile, antiviral dosage. This report describes a chronic HSV-2 genital lesion, with resistance to current antivirals and novel mutations within viral TK and DNA pol which may confer antiviral resistance.


Assuntos
Herpes Simples , Herpesvirus Humano 2 , Aciclovir/farmacologia , Aciclovir/uso terapêutico , Antivirais/farmacologia , Antivirais/uso terapêutico , Cidofovir/uso terapêutico , DNA Polimerase Dirigida por DNA/genética , Farmacorresistência Viral/genética , Foscarnet/uso terapêutico , Genitália , Herpes Simples/tratamento farmacológico , Herpesvirus Humano 2/genética , Humanos , Imiquimode/uso terapêutico , Mutação , Obesidade , Timidina Quinase/genética , Timidina Quinase/uso terapêutico , Valaciclovir/uso terapêutico
5.
Sci Rep ; 12(1): 7211, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35508515

RESUMO

With the COVID-19 pandemic, documenting whether health care workers (HCWs) are at increased risk of SARS-CoV-2 contamination and identifying risk factors is of major concern. In this multicenter prospective cohort study, HCWs from frontline departments were included in March and April 2020 and followed for 3 months. SARS-CoV-2 serology was performed at month 0 (M0), M1, and M3 and RT-PCR in case of symptoms. The primary outcome was laboratory-confirmed SARS-CoV-2 infection at M3. Risk factors of laboratory-confirmed SARS-CoV-2 infection at M3 were identified by multivariate logistic regression. Among 1062 HCWs (median [interquartile range] age, 33 [28-42] years; 758 [71.4%] women; 321 [30.2%] physicians), the cumulative incidence of SARS-CoV-2 infection at M3 was 14.6% (95% confidence interval [CI] [12.5; 16.9]). Risk factors were the working department specialty, with increased risk for intensive care units (odds ratio 1.80, 95% CI [0.38; 8.58]), emergency departments (3.91 [0.83; 18.43]) and infectious diseases departments (4.22 [0.92; 18.28]); current smoking was associated with reduced risk (0.36 [0.21; 0.63]). Age, sex, professional category, number of years of experience in the job or department, and public transportation use were not significantly associated with laboratory-confirmed SARS-CoV-2 infection at M3. The rate of SARS-CoV-2 infection in frontline HCWs was 14.6% at the end of the first COVID-19 wave in Paris and occurred mainly early. The study argues for an origin of professional in addition to private life contamination and therefore including HCWs in the first-line vaccination target population. It also highlights that smokers were at lower risk.Trial registration The study has been registered on ClinicalTrials.gov: NCT04304690 first registered on 11/03/2020.


Assuntos
COVID-19 , Adulto , Feminino , Humanos , Masculino , Estudos de Coortes , COVID-19/epidemiologia , Pessoal de Saúde , Incidência , Pandemias , Paris/epidemiologia , Estudos Prospectivos , Fatores de Risco , SARS-CoV-2
7.
Int J Infect Dis ; 108: 610-616, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34146691

RESUMO

OBJECTIVES: To assess the prevalence of sexually transmitted infections (STIs), antimicrobial resistance and cervical lesions among women from Sikasso, Mali. METHODS: Women infected with human immunodeficiency virus (HIV) (n=44) and HIV-negative women (n=96) attending cervical cancer screening were included. Screening for human papillomavirus (HPV), Chlamydia trachomatis (CT), Mycoplasma genitalium (MG), Neisseria gonorrhoeae (NG) and Trichomonas vaginalis (TV) was performed using polymerase chain reaction assays, and herpes simplex virus (HSV-1/2) serological status was assessed using enzyme-linked immunosorbent assays. Antibiotic resistance tests were performed for MG- and NG-positive cases. RESULTS: A high prevalence of high-risk HPV (hrHPV) infection (63%) was found. This was associated with cervical lesions in 7.5% of cases. An unusual distribution was found, with HPV31, HPV56 and HPV52 being the most prevalent. The hrHPV distribution differed by HIV status, with HIV-positive cases having HPV35/31/51-52-56 and HIV-negative cases having HPV31/56/52. The seroprevalence of HSV-2 was 49%, and the prevalence of other STIs was as follows: CT, 4%; MG, 9%; NG, 1%; and TV, 7%. Five of nine MG-positive specimens and the NG strains obtained were resistant to fluoroquinolone. CONCLUSIONS: These results showed high prevalence of hrHPV and fluoroquinolone resistance in several NG and MG strains. Further studies are required to confirm these data in Mali, and to improve prevention, screening and management of cervical cancer and other STIs in women.


Assuntos
Infecções por Chlamydia , Gonorreia , Infecções por Papillomavirus , Infecções Sexualmente Transmissíveis , Neoplasias do Colo do Útero , Antibacterianos/farmacologia , Chlamydia trachomatis , Farmacorresistência Bacteriana , Detecção Precoce de Câncer , Feminino , Gonorreia/diagnóstico , Gonorreia/epidemiologia , Humanos , Mali/epidemiologia , Neisseria gonorrhoeae , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/epidemiologia , Prevalência , Estudos Soroepidemiológicos , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/epidemiologia
8.
Nat Commun ; 12(1): 844, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33558507

RESUMO

There are only few data concerning persistence of neutralizing antibodies (NAbs) among SARS-CoV-2-infected healthcare workers (HCW). These individuals are particularly exposed to SARS-CoV-2 infection and at potential risk of reinfection. We followed 26 HCW with mild COVID-19 three weeks (D21), two months (M2) and three months (M3) after the onset of symptoms. All the HCW had anti-receptor binding domain (RBD) IgA at D21, decreasing to 38.5% at M3 (p < 0.0001). Concomitantly a significant decrease in NAb titers was observed between D21 and M2 (p = 0.03) and between D21 and M3 (p < 0.0001). Here, we report that SARS-CoV-2 can elicit a NAb response correlated with anti-RBD antibody levels. However, this neutralizing activity declines, and may even be lost, in association with a decrease in systemic IgA antibody levels, from two months after disease onset. This short-lasting humoral protection supports strong recommendations to maintain infection prevention and control measures in HCW, and suggests that periodic boosts of SARS-CoV-2 vaccination may be required.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Pessoal de Saúde/estatística & dados numéricos , SARS-CoV-2/imunologia , Adulto , Sítios de Ligação/imunologia , COVID-19/virologia , Linhagem Celular Tumoral , Feminino , Humanos , Imunoglobulina A/imunologia , Masculino , Pessoa de Meia-Idade , Ligação Proteica , Receptores Virais/metabolismo , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Fatores de Tempo
9.
Emerg Infect Dis ; 26(9): 2231-2234, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32818389

RESUMO

We report a fatal case of measles inclusion-body encephalitis occurring in a woman from Romania with AIDS. After an extensive but unsuccessful diagnostic evaluation, a pan-pathogen shotgun metagenomic approach revealed a measles virus infection. We identified no mutations previously associated with neurovirulence.


Assuntos
Síndrome da Imunodeficiência Adquirida , Sarampo , Panencefalite Esclerosante Subaguda , Adulto , Encéfalo/diagnóstico por imagem , Feminino , França , Humanos , Sarampo/diagnóstico , Vírus do Sarampo/genética , Romênia
10.
Front Oncol ; 10: 822, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32528893

RESUMO

In some western countries, an increasing incidence of oral squamous cell carcinoma (OSCC) has been observed in non-smoker non-drinker patients (NSND), mostly in women with HPV-negative OSCC. In the context of the unknown etiology and mechanisms of tumorigenesis of OSCC in NSND, we discuss data supporting the hypothesis of a viral origin not related to HPV. OSCC from NSND are characterized by an antiviral DNA methylation and gene expression signature. Based on the similar increasing incidence of oral tongue SCC (OTSCC) and oropharyngeal SCC (OPSCC) in young women and men respectively, we hypothesize that changes in sexual behaviors may lead to an increasing incidence of herpesvirus in the oral cavity, especially HSV-2, similarly to what has already been described in HPV-positive OPSCC. Because viral genome integration has not been detected in OSCC from NSND, a "hit and run" viral mechanism involving epigenome deregulation could therefore play a key role at early steps of oral carcinogenesis in this population of patients. In conclusion, epidemiological, clinical and molecular data supports a "hit and run" viral origin of OSCC from NSND.

11.
Antivir Ther ; 23(8): 665-675, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30028308

RESUMO

BACKGROUND: Cacicol®, a topical eye biopolymer containing a poly-carboxymethylglucose sulfate solution that is a regenerating matrix therapy agent, intended for wound healing of persistent corneal epithelial defects. Based on the chemical composition, we hypothesized that Cacicol® may compete with natural heparan sulfate (HS) which initiates cell surface attachment of herpes simplex virus type-1 (HSV-1), varicella zoster virus (VZV) and human adenovirus (HAdV), three viruses associated with corneal infections. METHODS: Cacicol® was compared to vehicle in the following viral strains: HSV-1 SC16 strain and HSV-1 PSLR, a clinical isolate highly resistant to acyclovir and foscarnet; VZV ATH and VZV FLO, two VZV clinical isolates; and HAdV-D37 strain. Viruses in Cacicol® or vehicle were added to cells for 1 h during adsorption then viral replication was assessed by plaque reduction assays on Vero cells for HSV-1 and MeWo cells for VZV and by immunostaining assay on Hep-2 cells for HAdV-D37. RESULTS: The vehicle had no effect, dose-dependent effects were demonstrated when HSV-1 SC16, HSV-1 PSLR, VZV ATH and VZV FLO were inoculated in the presence of Cacicol®, inhibiting viral replication by 98.4%, 98.9%, 90.1% and 89.0%, respectively. Cacicol® had no antiviral effect against HAdV-D37. CONCLUSIONS: Cacicol® has a significant antiviral activity on HSV-1 and VZV, but not on HAdV-D37. The lack of effect on HAdV is probably because it is less dependent on HS interactions for cell entry. Clinical studies are necessary to determine Cacicol® for an adjunct or alternative therapy of corneal HSV-1 or VZV infection, particularly for the management of antiviral resistant HSV-1.


Assuntos
Antivirais/administração & dosagem , Heparitina Sulfato/administração & dosagem , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 3/efeitos dos fármacos , Ceratite Herpética/virologia , Regeneração , Animais , Materiais Biomiméticos , Células Cultivadas , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Ceratite Herpética/diagnóstico , Ceratite Herpética/tratamento farmacológico , Células Vero , Ensaio de Placa Viral , Replicação Viral/efeitos dos fármacos
12.
Antiviral Res ; 151: 20-23, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29337163

RESUMO

We report the first application of ultra-deep sequencing (UDS) to varicella-zoster virus (VZV) genotypic antiviral testing in a case of acyclovir-resistant VZV infection initially detected by Sanger sequencing within a deeply immunocompromised heart transplant recipient. As added-value compared to Sanger analysis, UDS revealed complex dynamics of viral population under antiviral pressure. Varicella-zoster virus (VZV) is a ubiquitous human herpesvirus affecting populations worldwide. VZV is commonly acquired in youth whose primary infection usually manifests as benign varicella (chickenpox). After the initial infection, the virus establishes lifelong latency in sensory ganglia leading to a risk of subsequent reactivation. Reactivation usually results in the development of localized herpes zoster (HZ) lesions, a painful skin rash commonly known as shingles (Cohen, 2013). The incidence and severity of HZ increase with impaired specific cell-mediated immunity mainly as a result of increasing age, malignancy, immunodeficiency, organ transplantation, or immunosuppressive drug therapy (Cohen, 2013; Koo et al., 2014; Pavlopoulou et al., 2015). In particular, HZ remains a significant cause of morbidity among solid organ transplant (SOT) recipients, especially in patients undergoing heart transplantation (HT) compared with liver, kidney, or lung transplant recipients (Carby et al., 2007; Koo et al., 2014; Pavlopoulou et al., 2015). These particular individuals are at increased risk of primary infection, reactivation followed by dissemination with visceral involvement and associated with bacterial superinfection, and chronic recurrences (Cohen, 2013). VZV infections may also engender debilitating neuralgia among highly immunocompromised patients (Sampathkumar et al., 2009). HT is also associated with the risk of reactivation of other latent viruses belonging to the Herpesviridae family as herpes simplex virus (HSV). Currently licensed drugs to prevent or to cure HSV- or VZV-associated diseases target the viral DNA polymerase (Pol). Acyclovir (ACV) and its prodrug valacyclovir (VACV) are considered as the first-line therapy, whereas foscarnet (FOS) or cidofovir (CDV) constitute alternative options. After primophosphorylation by the viral thymidine kinase (TK), ACV targets the viral DNA polymerase and inhibits the viral genome replication by a chain termination mechanism. According to this mechanism of action, viral mutations conferring resistance to ACV have been mapped both in TK and Pol encoding genes. Viral mutations conferring resistance to FOS and CDV are only detected in Pol gene. VZV ACV-resistance is mostly mediated by TK alterations, consisting in either translational frameshifts, sometimes associated with premature stop codon, or amino acid substitutions. In the remaining cases, amino acid substitutions are detected within Pol (De et al., 2015; Piret and Boivin, 2014). Classically, Sanger sequencing has been recognized as the gold standard for the detection of drug resistance mutations (DRMs) within VZV TK and Pol genes (Perrier et al., 2016; Piret and Boivin, 2014). However, this approach cannot detect minor variants present at a frequency below 20%. Ultra-deep sequencing (UDS) has an enhanced sensitivity compared to Sanger method and allows quantitative evaluation of the viral mutants (Chin et al., 2013). We report here a case of VZV resistant infection in an HT recipient. Our retrospective study aimed at showing the utility of UDS for DRM detection as a complement of Sanger method.


Assuntos
Antivirais/administração & dosagem , Antivirais/farmacologia , Farmacorresistência Viral/genética , Herpes Zoster/tratamento farmacológico , Herpesvirus Humano 3/efeitos dos fármacos , Herpesvirus Humano 3/genética , Sequenciamento de Nucleotídeos em Larga Escala , DNA Polimerase Dirigida por DNA/genética , Farmacorresistência Viral/efeitos dos fármacos , Genótipo , Transplante de Coração/efeitos adversos , Herpes Zoster/imunologia , Herpes Zoster/virologia , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Mutação , Estudos Retrospectivos , Timidina Quinase/genética , Resultado do Tratamento
13.
Antiviral Res ; 138: 86-92, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27887982

RESUMO

The aim of this study was to characterize Human Cytomegalovirus (HCMV) drug resistance mutations in UL97 and UL54 genes in allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients in Portugal. We have performed a retrospective study with 22 patients from a cohort of patients with different haematological malignancies submitted to allo-HSCT between 2010 and 2014. Patients were selected according to clinical and laboratory data of HCMV infection and management. HCMV resistance mutations were characterized by sequencing of UL97 and UL54 genes. Sequence data were compared with: 1) HCMV genome reference strain AD169; and also 2) UL97 from Merlin strain (GenBank: AY446894.2), and UL54 from TB40/E strain (GenBank: ABV71585.1). Resistance mutations were identified in seven patients (32%): five harboured resistance mutations in UL97: A594V (n = 2), C592G (n = 1), L595W (n = 1), and C603W (n = 1); and two harboured resistance mutations in UL54: P522S and L957F, one in each patient. Several natural polymorphisms and unknown mutations were found in both UL97 and UL54, with the majority of the patients harbouring more than one unknown mutation in UL97 but only one in UL54. No simultaneous mutations were found. This is the first study in Portugal to characterize HCMV UL97 and UL54 sequences and to identify HCMV drug-resistance mutations in allo-HSCT patients. The UL97 resistance mutations found were amongst the most frequent resistant mutations, while UL54 L957F mutation was here reported for the first time in a clinical specimen. This information provides important information regarding HCMV strains and antiviral resistance in our population.


Assuntos
Antivirais/farmacologia , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/genética , Farmacorresistência Viral/genética , Transplante de Células-Tronco Hematopoéticas , Adolescente , Adulto , Criança , Pré-Escolar , Infecções por Citomegalovirus/epidemiologia , Infecções por Citomegalovirus/virologia , DNA Viral/efeitos dos fármacos , DNA Polimerase Dirigida por DNA/genética , Feminino , Ganciclovir/farmacologia , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Mutação , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Polimorfismo Genético , Portugal/epidemiologia , Estudos Retrospectivos , Análise de Sequência de DNA , Transplantados , Proteínas Virais/genética , Adulto Jovem
14.
Rev Med Virol ; 26(3): 161-82, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26990717

RESUMO

Human cytomegalovirus (HCMV) infection is a major cause of morbidity and mortality in allogeneic hematopoietic stem cell transplant recipients. The significant clinical impact of HCMV infection and progression to HCMV disease among allogeneic hematopoietic stem cell transplant recipients has been reduced by prophylactic, preemptive, and curative treatments using ganciclovir, valganciclovir, foscarnet, and cidofovir. Resistance to (val)ganciclovir results from mutations localized in HCMV UL97 gene (encoding the pUL97 phosphotransferase), UL54 gene (encoding the pUL54 DNA polymerase), or both genes, whereas foscarnet and cidofovir resistance results from mutations localized within UL54 gene only. This review is focused on HCMV antiviral drug resistance, including the functions of target genes of antivirals, the mechanisms of antiviral resistance, the different mutations in pUL97 and pUL54 that have been identified in either clinical isolates or laboratory strains, and their impact on HCMV susceptibility to antiviral drugs. It emphasizes the importance of proving that observed genetic changes confer resistance so they can be distinguished from polymorphisms. Because of the emergence of HCMV resistance to currently available drugs, novel drugs are urgently needed for the therapeutic management of HCMV-resistant infections in hematopoietic stem cell transplant patients.


Assuntos
Antivirais/farmacologia , Antivirais/uso terapêutico , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/virologia , Citomegalovirus/efeitos dos fármacos , Farmacorresistência Viral , Transplante de Células-Tronco Hematopoéticas , Interações Hospedeiro-Patógeno , Citomegalovirus/genética , Citomegalovirus/imunologia , Infecções por Citomegalovirus/imunologia , DNA Polimerase Dirigida por DNA/genética , Gerenciamento Clínico , Genótipo , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/imunologia , Humanos , Mutação , Fenótipo , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Proteínas Virais/genética
15.
Rev Prat ; 66(9): 1007-1014, 2016 Nov.
Artigo em Francês | MEDLINE | ID: mdl-30512372

RESUMO

Research for novel antivirals: where are we going? Antiviral drugs have become a critical component of anti-infective treatments, as illustrated by the development of antiretrovirals and antiviral drugs directed against hepatitis B and C viruses. Several other molecules are used in clinical practice against herpesviruses, adenoviruses, poxviruses, papillomaviruses and influenza viruses. Current antivirals often target viral enzymes involved in the replication of viral genomes. They also target the early stages of binding and intracellular penetration of viral particles and the late steps leading to their assembly, maturation and release. Most nucleoside analogs such as acyclovir and nucleotide analogs such as cidofovir, require phosphorylation prior to inhibit the activity of DNA or RNA polymerases through mechanisms of competition and optionally termination. Foscarnet, a pyrophosphate analog, makes this inhibition directly without any modification. Antiretrovirals also include protease, integrase and entry inhibitors while the neuraminidase inhibitors have proven to be effective against influenza viruses. Research for novel drugs aims at increasing the number and specificity of antivirals to overcome the current limitations of antiviral chemotherapy which include the inability to eradicate latent viral infections, emergence of resistance, adverse effects related to cell toxicity and cost. It is essential that economic imperatives do not block or distort the expected progresses in this particularly innovative field of contemporary medicine.


Où en est la recherche sur les antiviraux ? Les antiviraux sont devenus une composante essentielle des traitements anti-infectieux, comme cela est illustré par le développement des antirétroviraux et des antiviraux dirigés contre les virus des hépatites B et C. Plusieurs autres molécules sont utilisées en pratique clinique contre les herpèsvirus, adénovirus, poxvirus, papillomavirus et virus grippaux. Les antiviraux actuels ciblent fréquemment des enzymes virales impliquées dans la réplication des génomes viraux. Ils ciblent aussi les étapes précoces de fixation et de pénétration intracellulaire des particules virales, ainsi que les étapes tardives conduisant à leur assemblage, leur maturation et leur libération. La plupart des analogues nucléosidiques tels que l'aciclovir, et les analogues nucléotidiques tels que le cidofovir, nécessitent une phosphorylation préalable pour inhiber, par un mécanisme de compétition et éventuellement de terminaison, l'activité d'une ADN ou d'une ARN polymérase. Le foscarnet, analogue de pyrophosphate, exerce cette inhibition directement sans modification. Les antirétroviraux incluent également des inhibiteurs de protéase, d'intégrase et d'entrée du virus, alors que les inhibiteurs de la neuraminidase ont montré leur efficacité contre les virus grippaux. La recherche sur les antiviraux vise à augmenter leur nombre et leur spécifi- cité d'action pour dépasser les limitations actuelles de la chimiothérapie antivirale que sont l'impossibilité à éradiquer les infections virales latentes, l'émergence de la résistance, les effets indésirables liés à la relative toxicité cellulaire et le coût. Il est essentiel que les impératifs économiques ne viennent pas bloquer ou biaiser les progrès attendus dans un domaine particulièrement innovant de la médecine contemporaine.

16.
Antiviral Res ; 111: 8-12, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25194992

RESUMO

Currently approved anti-human cytomegalovirus (CMV) drugs, all targeting the viral DNA polymerase, are associated with significant toxicities and emergence of drug resistance. In this context, CMV terminase complex constitutes a promising target for novel antiviral compounds. In this study, we describe the low natural polymorphism (interstrain identity >97.7% at both nucleotide and amino acid levels) of the terminase subunits pUL56 and pUL89, and the portal protein pUL104, among 63 CMV clinical strains, and we show that the CMV resistance profile to current DNA polymerase inhibitors has no impact on the natural polymorphism of CMV terminase complex. These results support the idea that both CMV clinical strains exhibiting either susceptibility or resistance to current CMV DNA polymerase inhibitors are comparably sensitive to novel inhibitors of CMV terminase complex, such as letermovir.


Assuntos
Antivirais/farmacologia , Infecções por Citomegalovirus/virologia , Citomegalovirus/enzimologia , Endodesoxirribonucleases/genética , Polimorfismo Genético , Proteínas Virais/genética , Proteínas Estruturais Virais/genética , Citomegalovirus/classificação , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/genética , Farmacorresistência Viral , Endodesoxirribonucleases/metabolismo , Humanos , Filogenia , Proteínas Virais/metabolismo , Proteínas Estruturais Virais/metabolismo
17.
Antiviral Res ; 111: 36-41, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25218782

RESUMO

The widespread use of acyclovir (ACV) and the increasing number of immunocompromised patients have raised concern about an increase in ACV-resistant herpes simplex virus (HSV). ACV resistance has traditionally been a major concern for immunocompromised patients with a frequency reported between 2.5% and 10%. The aim of this study was to reassess the status of HSV resistance to ACV in immunocompetent and immunocompromised patients over a ten year period, between 2002 and 2011. This was done by retrospectively following 1425 patients. In immunocompetent patients, prevalence of resistance did not exceed 0.5% during the study period; whereas in immunocompromised patients, a significant increase was observed, rising from 3.8% between 2002 and 2006 (7/182 patients) to 15.7% between 2007 and 2011 (28/178) (p=0.0001). This sharp rise in resistance may largely be represented by allogeneic hematopoietic stem cell transplant patients, in which the prevalence of ACV resistance rose similarly from 14.3% (4/28) between 2002 and 2006 to 46.5% (26/56) between 2007 and 2011 (p=0.005). No increase in ACV resistance was detected in association with other types of immune deficiencies. Genotypic characterization of HSV UL23 thymidine kinase and UL30 DNA polymerase genes revealed 11 and 7 previously unreported substitutions, respectively. These substitutions may be related to potential polymorphisms, drug resistance, or other mutations of unclear significance.


Assuntos
Aciclovir/uso terapêutico , Antivirais/uso terapêutico , Farmacorresistência Viral , Herpes Simples/tratamento farmacológico , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , França/epidemiologia , Herpes Simples/epidemiologia , Herpes Simples/virologia , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/metabolismo , Herpesvirus Humano 2/genética , Herpesvirus Humano 2/metabolismo , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Mutação , Estudos Retrospectivos , Proteínas Virais/genética , Adulto Jovem
18.
Biol Blood Marrow Transplant ; 20(12): 1958-67, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25139217

RESUMO

Cytomegalovirus (CMV) infection is 1 of the leading causes of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (aHSCT), mainly within the first 100 days after transplantation. We aimed to characterize CMV infection in a cohort of 305 patients with different malignancies undergoing aHSCT at the Portuguese Institute of Oncology of Porto between January 2008 and December 2012. In total, 184 patients (60.3%) developed CMV infection, mainly viral reactivations rather than primary infections (96.2% versus 3.8%, respectively). The majority of patients (166 of 184) developed CMV infection ≤100 days after transplantation, with median time to infection of 29 days (range, 0 to 1285) and median duration of infection of 10 days (range, 2 to 372). Multivariate analysis revealed that CMV infection was increased in donor (D)-/recipient (R)+ and D+/R+ (odds ratio [OR], 10.5; 95% confidence interval [CI], 4.35 to 25.4; P < .001) and in patients with mismatched or unrelated donors (OR, 2.54; 95% CI, 1.34 to 4.80; P = .004). Cox regression model showed that the risk of death was significantly increased in patients >38 years old (OR, 1.89; 95% CI, 1.14 to 3.12; P = .0137), who underwent transplantation with peripheral blood (OR, 3.02; 95% CI, 1.33 to 6.86; P = .008), with mismatched or unrelated donor (OR, 2.16; 95% CI, 1.48 to 3.13; P < .001), and who developed CMV infection (OR, 1.76; 95% CI, 1.07 to 2.90; P = .025). Moreover, patients who developed CMV infection had a significantly reduced median post-transplantation survival (16 versus 36 months; P = .002).


Assuntos
Infecções por Citomegalovirus , Transplante de Células-Tronco Hematopoéticas , Neoplasias/mortalidade , Neoplasias/terapia , Transplante de Células-Tronco de Sangue Periférico , Adolescente , Adulto , Fatores Etários , Aloenxertos , Infecções por Citomegalovirus/etiologia , Infecções por Citomegalovirus/mortalidade , Infecções por Citomegalovirus/terapia , Intervalo Livre de Doença , Seguimentos , Humanos , Pessoa de Meia-Idade , Portugal/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida
19.
Am J Respir Crit Care Med ; 189(10): 1240-9, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24646009

RESUMO

RATIONALE: The biology of fatal pandemic influenza infection remains undefined. OBJECTIVES: To characterize the virologic and immune parameters associated with severity or death in patients who required mechanical ventilation for A(H1N1) 2009 pneumonia of various degrees of severity during the two waves of the 2009-2011 pandemic in Paris, France. METHODS: This multicenter study included 34 unvaccinated patients with very severe or fatal confirmed influenza A(H1N1) infections. It analyzed plasma A(H1N1) 2009 reverse-transcriptase polymerase chain reaction, hemagglutinin 222G viral mutation, and humoral and cellular immune responses to the virus, assessed in hemagglutination inhibition (HI), microneutralization, ELISA, lymphoproliferative, ELISpot IFN-γ, and cytokine and chemokine assays. MEASUREMENTS AND MAIN RESULTS: The patients' median age was 35 years. Influenza A(H1N1) 2009 viremia was detected in 4 of 34 cases, and a 222G hemagglutinin mutation in 7 of 17 cases, all of them with sequential organ failure assessment greater than or equal to 8. HI antibodies were detectable in 19 of 26 survivors and undetectable in all six fatal fulminant cases. ELISA and microneutralization titers were concordant. B-cell immunophenotyping and plasma levels of immunoglobulin classes did not differ between patients who survived and died. After immune complex dissociation, influenza ELISA serology became strongly positive in the bronchoalveolar lavage of the two fatal cases tested. H1N1-specific T-cell responses in lymphoproliferative and IFN-γ assays were detectable in survivors' peripheral blood, and lymphoproliferative assays were negative in the three fatal cases tested. Plasma levels of IL-6 and IL-10 were high in fatal cases and correlated with severity. Finally, a negative HI serology 4 days after the onset of influenza symptoms predicted death from fulminant influenza (P = 0.04). CONCLUSIONS: Early negative A(H1N1) 2009 HI serology can predict death from influenza. This negative serology in fatal cases in young adults reflects the trapping of anti-H1N1 antibodies in immune complexes in the lungs, associated with poor specific helper T-cell response. Clinical trial registered with www.clinicaltrials.gov (NCT 01089400).


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/imunologia , Pneumonia Viral/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Adolescente , Adulto , Anticorpos Neutralizantes/sangue , Biomarcadores/sangue , Feminino , França , Glicoproteínas de Hemaglutininação de Vírus da Influenza/sangue , Humanos , Influenza Humana/sangue , Influenza Humana/complicações , Influenza Humana/diagnóstico , Influenza Humana/mortalidade , Interleucina-10/imunologia , Interleucina-6/imunologia , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/diagnóstico , Pneumonia Viral/mortalidade , Pneumonia Viral/virologia , Valor Preditivo dos Testes , Estudos Prospectivos , Unidades de Cuidados Respiratórios , Fatores de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença
20.
J Virol Methods ; 196: 32-5, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24184087

RESUMO

Human polyomavirus BK (BKV) is increasingly recognized as an opportunistic pathogen in transplant recipients. The aim of this work was to evaluate the artus(®) BK Virus QS-RGQ assay on the QIAsymphony RGQ system in whole blood (WB) samples (tests performed in an off-label capacity) according to different BKV genotypes by comparison with a laboratory-developed assay. BKV loads were measured in 111 WB samples and BKV genotype was determined by sequencing the full-length VP1 gene. The artus(®) assay exhibited a limit of detection of 77copies/mL, a linearity range from 3.0 to 6.0log10copies/mL, intra-assay and inter-assay coefficients of variation ranging from 0.65% to 5.18%. Regarding BKV quantitation, artus(®) and laboratory-developed assays were highly correlated (Spearman correlation coefficient Rho=0.79; P<0.0001) with an excellent overall agreement (96.4%) and no significant quantitative difference according to Bland-Altman analysis (mean difference: -0.34log10copies/mL). The results did not show any influence of BKV genotype on BKV quantitation by the artus(®) assay, except a potential underquantitation of BKV subtype Ia which deserves further confirmation. In conclusion, the QIAsymphony RGQ system appears to be appropriate for the quantitation of BKV load in WB samples.


Assuntos
Vírus BK/isolamento & purificação , Sangue/virologia , DNA Viral/genética , Infecções por Polyomavirus/virologia , Infecções Tumorais por Vírus/virologia , Carga Viral/métodos , Vírus BK/classificação , Vírus BK/genética , Genótipo , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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