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1.
PLoS One ; 18(3): e0282147, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36996137

RESUMO

High rates of unintended pregnancies worldwide indicate a need for more accessible and acceptable methods of contraception. We have developed a monoclonal antibody, the Human Contraception Antibody (HCA), for use by women in vaginal films and rings for contraception. The divalent F(ab')2 region of HCA binds to an abundant male reproductive tract-specific antigen, CD52g, and potently agglutinates sperm. Certain other antibody activities mediated by the Fc region such as mucus trapping, complement-dependent cytotoxicity (CDC) and antibody-dependent cellular phagocytosis (ADCP) could have beneficial or negative effects. The purpose of this study was to document HCA Fc effector functions and determine whether an engineered variant of HCA with a modified Fc region, HCA-LALAPG, retains desirable contraceptive activity while minimizing Fc-mediated effects. Fab and Fc functions were compared between HCA and HCA-LALAPG. Fab activity was assessed using sperm agglutination and modified swim-up ("sperm escape") assays. Fc functions were assessed by CDC (sperm immobilization), ADCP, and cervical mucus penetration assays. HCA and HCA-LALAPG showed equivalent activity in assays of Fab function. In the assays of Fc function, HCA supported strong CDC, ADCP, and sperm trapping in cervical mucus whereas HCA-LALAPG demonstrated little to no activity. HCA and the HCA-LALAPG variant were both highly effective in the sperm agglutination assays but differed in Fc mediated functions. Use of the HCA-LALAPG variant for contraception in women could reduce antibody-mediated inflammation and antigen presentation but may have reduced contraceptive efficacy due to much weaker sperm trapping in mucus and complement-dependent sperm immobilization activity.


Assuntos
Sêmen , Aglutinação Espermática , Gravidez , Humanos , Masculino , Feminino , Aglutinação Espermática/genética , Anticorpos Monoclonais , Anticoncepcionais , Anticoncepção , Citotoxicidade Celular Dependente de Anticorpos
2.
Open Forum Infect Dis ; 8(12): ofab563, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34888401

RESUMO

BACKGROUND: Favipiravir is used to treat influenza, and studies demonstrate that it has antiviral activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: We performed a randomized, open-label, multicenter, phase 2 proof-of-concept trial of favipiravir in hospitalized adult patients with polymerase chain reaction (PCR)-positive coronavirus disease 2019 (COVID-19). Patients were randomized to standard of care (SOC) or favipiravir treatment (1800mg per os twice a day [b.i.d.] on day 1, followed by 1000mg b.i.d. for 13 days). The primary end point was time to viral clearance on day 29. RESULTS: Fifty patients were enrolled and stratified by disease severity (critical disease, severe disease, or mild to moderate disease). Nineteen patients were censored from the event of viral clearance based on being SARS-CoV-2 PCR-negative at the study outset, being PCR-positive at day 29, or because of loss to follow-up. Data from the 31 remaining patients who achieved viral clearance show enhanced viral clearance in the favipiravir group compared with the SOC group by day 29, with 72% of the favipiravir group and 52% of the SOC group being evaluable for viral clearance through day 29. The median time to viral clearance was 16.0 days (90% CI, 12.0 to 29.0) in the favipiravir group and 30.0 days (90% CI, 12.0 to 31.0) in the SOC group. A post hoc analysis revealed an effect in the subgroup of patients who were neutralizing antibody-negative at randomization. Treatment-emergent adverse events were equally distributed between the groups. CONCLUSIONS: We demonstrate that favipiravir can be safely administered to hospitalized adults with COVID-19 and believe that further studies are warranted. CLINICALTRIALSGOV REGISTRATION: NCT04358549.

3.
Open Forum Infect Dis ; 8(8): ofab208, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34409120

RESUMO

Massachusetts is one of the epicenters of the opioid epidemic and has been severely impacted by injection-related viral and bacterial infections. A recent increase in newly diagnosed human immunodeficiency virus (HIV) infections among persons who inject drugs in the state highlights the urgent need to address and bridge the overlapping epidemics of opioid use disorder (OUD) and injection-related infections. Building on an established relationship between the Massachusetts Department of Public Health and Boston Medical Center, the Infectious Diseases section has contributed to the development and implementation of a cohesive response involving ambulatory, inpatient, emergency department, and community-based services. We describe this comprehensive approach including the rapid delivery of antimicrobials for the prevention and treatment of HIV, sexually transmitted diseases, systemic infections such as endocarditis, bone and joint infections, as well as curative therapy for chronic hepatitis C virus in a manner that is accessible to patients on the addiction-recovery continuum. We also provide an overview of programs that provide access to medications for OUD, harm reduction services including overdose education, and distribution of naloxone. Finally, we outline lessons learned to inform initiatives in other settings.

4.
EBioMedicine ; 69: 103478, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34256345

RESUMO

BACKGROUND: Approximately 40% of human pregnancies are unintended, indicating a need for more acceptable effective contraception methods. New antibody production systems make it possible to manufacture reagent-grade human monoclonal antibodies (mAbs) for clinical use. We used the Nicotiana platform to produce a human antisperm mAb and tested its efficacy for on-demand topical contraception. METHODS: Heavy and light chain variable region DNA sequences of a human IgM antisperm antibody derived from an infertile woman were inserted with human IgG1 constant region sequences into an agrobacterium and transfected into Nicotiana benthamiana. The product, an IgG1 mAb ["Human Contraception Antibody" (HCA)], was purified on Protein A columns, and QC was performed using the LabChip GXII Touch protein characterization system and SEC-HPLC. HCA was tested for antigen specificity by immunofluorescence and western blot assays, antisperm activity by sperm agglutination and complement dependent sperm immobilization assays, and safety in a human vaginal tissue (EpiVaginal™) model. FINDINGS: HCA was obtained at concentrations ranging from 0.4 to 4 mg/ml and consisted of > 90% IgG monomers. The mAb specifically reacted with a glycan epitope on CD52g, a glycoprotein produced in the male reproductive tract and found in abundance on sperm. HCA potently agglutinated sperm under a variety of relevant physiological conditions at concentrations ≥ 6.25 µg/ml, and mediated complement-dependent sperm immobilization at concentrations ≥ 1 µg/ml. HCA and its immune complexes did not induce inflammation in EpiVaginal™ tissue. INTERPRETATION: HCA, an IgG1 mAb with potent sperm agglutination and immobilization activity and a good safety profile, is a promising candidate for female contraception. FUNDING: This research was supported by grants R01 HD095630 and P50HD096957 from the National Institutes of Health.


Assuntos
Anticorpos Monoclonais/imunologia , Antígeno CD52/imunologia , Anticoncepção Imunológica/métodos , Espermatozoides/imunologia , Vacinas Anticoncepcionais/imunologia , Especificidade de Anticorpos , Feminino , Humanos , Masculino
5.
Open Forum Infect Dis ; 8(6): ofab164, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34189164

RESUMO

To determine the association between immunosuppression and time to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) polymerase chain reaction (PCR) clearance, we studied 3758 adults retested following initial SARS-CoV-2 infection. Cox proportional hazards models demonstrated delayed PCR clearance with older age, multiple comorbidities, and solid organ transplant but not by degree of immunocompromise. These findings challenge current retesting practices.

6.
PLoS Med ; 18(2): e1003495, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33534791

RESUMO

BACKGROUND: MB66 film is a multipurpose prevention technology (MPT) product with monoclonal antibodies (mAbs) against HIV-1 (VRC01-N) and HSV-1 and 2 (HSV8-N). The mAbs were produced by transient expression in Nicotiana benthamiana (N). We conducted a Phase I clinical trial to assess the safety, pharmacokinetics (PK), and ex vivo efficacy of single and repeated doses of MB66 when used intravaginally. METHODS AND FINDINGS: The clinical trial enrolled healthy reproductive-aged, sexually abstinent women. In Segment A, 9 women received a single MB66 film which was inserted into the vaginal posterior fornix by a clinician. In Segment B, 29 women were randomly assigned to MB66 (Active) or Placebo film groups and were instructed to insert 1 film vaginally for 7 consecutive days. Visits and clinical sampling occurred predose and at various time points after single and repeated film doses. The primary endpoint was number of adverse events (AEs) Grade 2 or higher related to product use. Secondary endpoints included film dissolution rate, Nugent score (a Gram stain scoring system to diagnose bacterial vaginosis), vaginal pH, post-use survey results, cytokine concentrations in cervicovaginal lavage (CVL) specimens (assessed by Luminex assay), mAb concentrations in vaginal fluid collected from 4 sites (assessed by ELISA), and HIV and HSV neutralization activity of CVL samples ex vivo (assessed by TZM-bl and plaque reduction assay, respectively). The product was generally safe and well tolerated, with no serious AEs recorded in either segment. The AEs in this study were primarily genitourinary in nature with the most commonly reported AE being asymptomatic microscopic hematuria. There were no differences in vaginal pH or Nugent scores or significant increases in levels of proinflammatory cytokines for up to 7 days after film insertion in either segment or between Active and Placebo groups. Acceptability and willingness to use the product were judged to be high by post-use surveys. Concentrations of VRC01-N and HSV8-N in vaginal secretions were assessed over time to generate pharmacokinetic curves. Antibody levels peaked 1 hour postdosing with Active film (median: 35 µg/mL) and remained significantly elevated at 24 hours post first and seventh film (median: 1.8 µg/mL). Correcting for sample dilution (1:20), VRC01-N concentrations ranged from 36 to 700 µg/mL at the 24-hour time point, greater than 100-fold the IC50 for VRC01 (0.32 µg/mL); HSV8-N concentrations ranged from 80 to 601 µg/mL, well above the IC50 of 0.1 µg/m. CVL samples collected 24 hours after MB66 insertion significantly neutralized both HIV-1 and HSV-2 ex vivo. Study limitations include the small size of the study cohort, and the fact that no samples were collected between 24 hours and 7 days for pharmacokinetic evaluation. CONCLUSIONS: Single and repeated intravaginal applications of MB66 film were safe, well tolerated, and acceptable. Concentrations and ex vivo bioactivity of both mAbs in vaginal secretions were significantly elevated and thus could provide protection for at least 24 hours postdose. However, further research is needed to evaluate the efficacy of MB66 film in women at risk for HIV and HSV infection. Additional antibodies could be added to this platform to provide protection against other sexually transmitted infections (STIs) and contraception. TRIAL REGISTRATION: ClinicalTrials.gov NCT02579083.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Anticorpos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Administração Intravaginal , Adolescente , Adulto , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Amplamente Neutralizantes/metabolismo , Anticorpos Amplamente Neutralizantes/uso terapêutico , Feminino , Anticorpos Anti-HIV/administração & dosagem , Anticorpos Anti-HIV/imunologia , HIV-1/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Profilaxia Pré-Exposição/métodos , Vagina/virologia , Adulto Jovem
7.
J Infect Dis ; 219(2): 275-283, 2019 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-30137482

RESUMO

Background: Condylomata acuminata (anogenital warts [AGWs]) are prevalent in human immunodeficiency virus (HIV)-infected individuals and sexually active populations at risk for HIV acquisition and have been associated with HIV transmission. We compared AGW specimens to control tissue specimens for abundance, types, and location of HIV target cells and for susceptibility to HIV infection in vitro, to provide biologic evidence that AGWs facilitate HIV transmission. Methods: We used immunohistologic staining to identify HIV target cells in AGW and control specimens. We also inoculated HIV in vitro into AGW and control specimens from HIV-negative men and assessed infection by means of TZM-bl and p24 assays. Results: CD1a+ dendritic cells, CD4+ T cells, and macrophages were significantly more abundant in the epidermis of AGW specimens than control specimens. These HIV target cells also often appeared in large focal accumulations in the dermis of AGW specimens. Two of 8 AGW specimens versus 0 of 8 control specimens showed robust infection with HIV in vitro. Conclusions: Compared with normal skin, AGWs contain significantly higher concentrations of HIV target cells that may be susceptible to HIV infection. Condylomata may thus promote HIV transmission, especially in the setting of typical lesion vascularity and friability. Prevention or treatment of AGWs may decrease the sexual transmission of HIV.


Assuntos
Condiloma Acuminado/patologia , Condiloma Acuminado/virologia , Infecções por HIV/transmissão , Adulto , Idoso , Antígenos CD , Antígenos de Diferenciação Mielomonocítica , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos , Condiloma Acuminado/imunologia , Células Dendríticas/imunologia , Células Dendríticas/patologia , Feminino , Granulócitos , Células HEK293 , Proteína do Núcleo p24 do HIV , Infecções por HIV/virologia , HIV-1 , Humanos , Antígenos CD15 , Macrófagos/patologia , Masculino , Pessoa de Meia-Idade , Papillomaviridae , Infecções por Papillomavirus/virologia , Receptores CXCR4 , Pele/imunologia , Pele/patologia , Adulto Jovem
8.
Genet Vaccines Ther ; 5: 5, 2007 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-17300725

RESUMO

Despite advances and options available in gene therapy for HIV-1 infection, its application in the clinical setting has been challenging. Although published data from HIV-1 clinical trials show safety and proof of principle for gene therapy, positive clinical outcomes for infected patients have yet to be demonstrated. The cause for this slow progress may arise from the fact that HIV is a complex multi-organ system infection. There is uncertainty regarding the types of cells to target by gene therapy and there are issues regarding insufficient transduction of cells and long-term expression. This paper discusses state-of-the-art molecular approaches against HIV-1 and the application of these treatments in current and ongoing clinical trials.

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