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1.
J Clin Immunol ; 42(3): 448-458, 2022 04.
Article in English | MEDLINE | ID: mdl-35000058

ABSTRACT

SARS-CoV-2 vaccination is known to induce antibodies that recognize also variants of concerns (VoCs) of the virus. However, epidemiological and laboratory evidences indicate that these antibodies have a reduced neutralization ability against VoCs. We studied binding and neutralizing antibodies against the Spike protein domains and subunits of the Wuhan-Hu-1 virus and its alpha, beta, delta VoCs and of seasonal betacoronaviruses (HKU1 and OC43) in a cohort of 31 health care workers prospectively followed post-vaccination with BNT162b2-Comirnaty. The study of sequential samples collected up to 64 days post-vaccination showed that serological assays measuring IgG against Wuhan-Hu-1 antigens were a poor proxy for VoC neutralization. In addition, in subjects who had asymptomatic or mild COVID-19 prior to vaccination, the loss of nAbs following disease could be rapid and accompanied by post-vaccination antibody levels similar to those of naïve vaccinees. Interestingly, in health care workers naïve for SARS-CoV-2 infection, vaccination induced a rapid and transient reactivation of pre-existing seasonal coronaviruses IgG responses that was associated with a subsequent reduced ability to neutralize alpha and beta VoCs.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Neutralizing , Antibodies, Viral , BNT162 Vaccine , COVID-19/prevention & control , COVID-19 Vaccines , Humans , Immunoglobulin G , Seasons , Vaccination
2.
Viruses ; 13(8)2021 07 29.
Article in English | MEDLINE | ID: mdl-34452351

ABSTRACT

Resistance-associated substitutions (RASs) may exist prior to treatment and contribute to the failure of treatment with direct-acting antivirals (DAAs). As the major site of HCV replication, naturally occurring variants with RASs may segregate into the liver. In the present study, we performed viral population sequencing to retrospectively investigate the NS3 and NS5A RAS profiles in 34 HIV/HCV coinfected patients naïve to anti-HCV treatment who underwent diagnostic liver biopsy between 2000 and 2006 and had liver and plasma samples available. Sixteen were infected by HCV genotype (GT) 1a, 11 by GT3a, and 7 by GT4d. The analysis of the NS3 domain in GT1a showed a difference in strain between the liver and plasma in three cases, with a preponderance of specific RASs in the liver compartment. In GT4d samples, 6/7 coupled liver and plasma samples were concordant with no RASs. Sequence analysis of the NS5A domain showed the presence of RASs in the livers of 2/16 patients harboring GT1a but not in the corresponding plasma. In GT4d, NS5A RASs were detected in 7/7 liver tissues and 5/7 plasma samples. NS3 domain and NS5A domain were found to be conserved in plasma and livers of patients infected with GT3a. Thus, RASs within GT1a and GT4d more likely segregate into the liver and may explain the emergence of resistant strains during DAA treatment.


Subject(s)
Amino Acid Substitution/drug effects , Antiviral Agents/pharmacology , Drug Resistance, Viral/genetics , Genotype , HIV Infections/virology , Hepacivirus/genetics , Hepatitis C/virology , Adult , Amino Acid Substitution/genetics , Antiviral Agents/therapeutic use , Female , HIV Infections/blood , HIV Infections/drug therapy , Hepacivirus/drug effects , Hepatitis C/blood , Hepatitis C/drug therapy , Humans , Male , RNA-Dependent RNA Polymerase/genetics , Retrospective Studies , Sequence Analysis, DNA , Viral Nonstructural Proteins/genetics
3.
Viruses ; 12(3)2020 02 28.
Article in English | MEDLINE | ID: mdl-32121164

ABSTRACT

We prospectively evaluated the frequency of natural resistance-associated substitutions (RASs) in the NS3 and NS5A regions according to different HCV genotypes and their possible effect on treatment outcome in HIV-1/HCV patients treated with direct-acting antivirals (DAAs). Baseline RASs in the NS3 and NS5A domains were investigated in 62 HIV-1/HCV patients treated with DAAs: 23 patients harbored HCV-GT1a, 26 harbored GT3a, and 13 harbored GT4d. A higher occurrence of RASs was found in the NS3 domain within GT1a (13/23) than GT3a (0/26) or GT4d (2/13). With regard to treatment outcome, NS3 RASs were detected in 14/56 patients with sustained virological response (SVR) and in 1/6 non-responder (NR) patients. Occurrence of RASs of NS5A domain was lower in SVR (4/56, had RASs) than in NR (3/6, had RASs). Evaluation of RASs at baseline instead of at virological failure, especially in the NS5A domain, could positively influence the choice of new DAA combinations for the treatment of HIV-1/HCV patients.


Subject(s)
Antiviral Agents/therapeutic use , Coinfection , Drug Resistance, Viral , HIV Infections/virology , Hepacivirus/genetics , Hepatitis C/drug therapy , Hepatitis C/virology , Viral Nonstructural Proteins/genetics , Adult , Alleles , Amino Acid Substitution , Antiviral Agents/pharmacology , Female , HIV Infections/drug therapy , Hepacivirus/drug effects , Humans , Male , Middle Aged , Mutation , Treatment Outcome
4.
J Acquir Immune Defic Syndr ; 82(2): 175-180, 2019 10 01.
Article in English | MEDLINE | ID: mdl-31192822

ABSTRACT

BACKGROUND: HIV-1 infection impairs cellular immunity, causing a detrimental effect on the natural course of hepatitis B virus (HBV) infection. HBV vaccination is less effective in HIV-1-infected patients. This study aimed to gain insight into HIV-1 infection with persistence of hepatitis B surface antigen (HBsAg) defining chronic hepatitis B infection (CBI) after a primary infection and the possible associated factors. SETTING: Division of Infectious Diseases, San Raffaele Hospital, Italy. METHODS: This retrospective study analyzed HIV-1-infected patients diagnosed with acute hepatitis B infection (AHB) based on clinical or laboratory records. CBI was defined as a positive HBsAg result recorded >6 months after an AHB diagnosis. Multivariate logistic regression was applied to assess factors (evaluated at AHB diagnosis) that were associated with CBI. RESULTS: Of 63 HIV-1-infected patients with AHB, 23 (36.5%) developed CBI. On multivariate analysis, CBI risk was less likely in patients with HIV-RNA of >50 copies/mL (adjusted odds ratio = 0.03, 95% confidence interval: 0.001 to 0.58, P = 0.021). Dually acting antiretroviral treatment, including one or more drugs active against HIV/HBV (lamivudine, emtricitabine, and tenofovir), seemed to be protective in terms of the clinical outcome of CBI (adjusted odds ratio = 0.07, 95% confidence interval: 0.01 to 1.02, P = 0.050). Among the 23 patients with CBI, 15 (65.2%) lost the hepatitis B e-antigen, while 11 (47.8%) had HBsAg seroclearance during follow-up. CONCLUSIONS: In HIV-1-infected subjects with AHB, the persistence of HBsAg seemed to occur frequently. Factors associated with a lower CBI risk were detectable HIV load and the use of dually acting antiretroviral treatment during AHB.


Subject(s)
HIV Infections/complications , HIV-1 , Hepatitis B, Chronic/etiology , Acute Disease , Adult , CD4 Lymphocyte Count , Female , HIV Infections/drug therapy , Hepatitis B Surface Antigens/blood , Hepatitis B, Chronic/immunology , Hepatitis B, Chronic/virology , Humans , Logistic Models , Male , Retrospective Studies , Viral Load
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