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1.
Cell Rep ; 41(3): 111496, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36261003

RESUMO

It is important to determine if severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections and SARS-CoV-2 mRNA vaccinations elicit different types of antibodies. Here, we characterize the magnitude and specificity of SARS-CoV-2 spike-reactive antibodies from 10 acutely infected health care workers with no prior SARS-CoV-2 exposure history and 23 participants who received SARS-CoV-2 mRNA vaccines. We found that infection and primary mRNA vaccination elicit S1- and S2-reactive antibodies, while secondary vaccination boosts mostly S1 antibodies. Using absorption assays, we found that SARS-CoV-2 infections elicit a large proportion of original antigenic sin-like antibodies that bind efficiently to the spike of common seasonal human coronaviruses but poorly to the spike of SARS-CoV-2. In converse, vaccination modestly boosts antibodies reactive to the spike of common seasonal human coronaviruses, and these antibodies cross-react more efficiently to the spike of SARS-CoV-2. Our data indicate that SARS-CoV-2 infections and mRNA vaccinations elicit fundamentally different antibody responses.


Assuntos
COVID-19 , Humanos , COVID-19/prevenção & controle , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/genética , Anticorpos Antivirais , Vacinação , RNA Mensageiro/genética
2.
Front Immunol ; 13: 834988, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35309299

RESUMO

Patients with COVID-19 present with a wide variety of clinical manifestations. Thromboembolic events constitute a significant cause of morbidity and mortality in patients infected with SARS-CoV-2. Severe COVID-19 has been associated with hyperinflammation and pre-existing cardiovascular disease. Platelets are important mediators and sensors of inflammation and are directly affected by cardiovascular stressors. In this report, we found that platelets from severely ill, hospitalized COVID-19 patients exhibited higher basal levels of activation measured by P-selectin surface expression and had poor functional reserve upon in vitro stimulation. To investigate this question in more detail, we developed an assay to assess the capacity of plasma from COVID-19 patients to activate platelets from healthy donors. Platelet activation was a common feature of plasma from COVID-19 patients and correlated with key measures of clinical outcome including kidney and liver injury, and APACHEIII scores. Further, we identified ferritin as a pivotal clinical marker associated with platelet hyperactivation. The COVID-19 plasma-mediated effect on control platelets was highest for patients that subsequently developed inpatient thrombotic events. Proteomic analysis of plasma from COVID-19 patients identified key mediators of inflammation and cardiovascular disease that positively correlated with in vitro platelet activation. Mechanistically, blocking the signaling of the FcγRIIa-Syk and C5a-C5aR pathways on platelets, using antibody-mediated neutralization, IgG depletion or the Syk inhibitor fostamatinib, reversed this hyperactivity driven by COVID-19 plasma and prevented platelet aggregation in endothelial microfluidic chamber conditions. These data identified these potentially actionable pathways as central for platelet activation and/or vascular complications and clinical outcomes in COVID-19 patients. In conclusion, we reveal a key role of platelet-mediated immunothrombosis in COVID-19 and identify distinct, clinically relevant, targetable signaling pathways that mediate this effect.


Assuntos
Plaquetas/imunologia , COVID-19/imunologia , Complemento C5a/metabolismo , Receptor da Anafilatoxina C5a/metabolismo , Receptores de IgG/metabolismo , SARS-CoV-2/fisiologia , Tromboembolia/imunologia , Adulto , Aminopiridinas/farmacologia , Células Cultivadas , Feminino , Hospitalização , Humanos , Masculino , Morfolinas/farmacologia , Ativação Plaquetária , Pirimidinas/farmacologia , Índice de Gravidade de Doença , Transdução de Sinais , Quinase Syk/antagonistas & inibidores
3.
JCI Insight ; 6(16)2021 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-34237028

RESUMO

Some studies suggest that recent common coronavirus (CCV) infections are associated with reduced COVID-19 severity upon SARS-CoV-2 infection. We completed serological assays using samples collected from health care workers to identify antibody types associated with SARS-CoV-2 protection and COVID-19 symptom duration. Rare SARS-CoV-2 cross-reactive antibodies elicited by past CCV infections were not associated with protection; however, the duration of symptoms following SARS-CoV-2 infections was significantly reduced in individuals with higher common betacoronavirus (ßCoV) antibody titers. Since antibody titers decline over time after CCV infections, individuals in our cohort with higher ßCoV antibody titers were more likely recently infected with common ßCoVs compared with individuals with lower antibody titers. Therefore, our data suggest that recent ßCoV infections potentially limit the duration of symptoms following SARS-CoV-2 infections through mechanisms that do not involve cross-reactive antibodies. Our data are consistent with the emerging hypothesis that cellular immune responses elicited by recent common ßCoV infections transiently reduce symptom duration following SARS-CoV-2 infections.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , COVID-19/imunologia , Pessoal de Saúde , SARS-CoV-2/imunologia , Adulto , Reações Cruzadas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
4.
bioRxiv ; 2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-33972943

RESUMO

Patients with COVID-19 present with a wide variety of clinical manifestations. Thromboembolic events constitute a significant cause of morbidity and mortality in patients infected with SARS-CoV-2. Severe COVID-19 has been associated with hyperinflammation and pre-existing cardiovascular disease. Platelets are important mediators and sensors of inflammation and are directly affected by cardiovascular stressors. In this report, we found that platelets from severely ill, hospitalized COVID-19 patients exhibit higher basal levels of activation measured by P-selectin surface expression, and have a poor functional reserve upon in vitro stimulation. Correlating clinical features to the ability of plasma from COVID-19 patients to stimulate control platelets identified ferritin as a pivotal clinical marker associated with platelet hyperactivation. The COVID-19 plasma-mediated effect on control platelets was highest for patients that subsequently developed inpatient thrombotic events. Proteomic analysis of plasma from COVID-19 patients identified key mediators of inflammation and cardiovascular disease that positively correlated with in vitro platelet activation. Mechanistically, blocking the signaling of the FcγRIIa-Syk and C5a-C5aR pathways on platelets, using antibody-mediated neutralization, IgG depletion or the Syk inhibitor fostamatinib, reversed this hyperactivity driven by COVID-19 plasma and prevented platelet aggregation in endothelial microfluidic chamber conditions, thus identifying these potentially actionable pathways as central for platelet activation and/or vascular complications in COVID-19 patients. In conclusion, we reveal a key role of platelet-mediated immunothrombosis in COVID-19 and identify distinct, clinically relevant, targetable signaling pathways that mediate this effect. These studies have implications for the role of platelet hyperactivation in complications associated with SARS-CoV-2 infection. ONE-SENTENCE SUMMARY: The FcγRIIA and C5a-C5aR pathways mediate platelet hyperactivation in COVID-19.

5.
medRxiv ; 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33907765

RESUMO

Recent common coronavirus (CCV) infections are associated with reduced COVID-19 severity upon SARS-CoV-2 infection, however the immunological mechanisms involved are unknown. We completed serological assays using samples collected from health care workers to identify antibody types associated with SARS-CoV-2 protection and COVID-19 severity. Rare SARS-CoV-2 cross-reactive antibodies elicited by past CCV infections were not associated with protection; however, the duration of symptoms following SARS-CoV-2 infections was significantly reduced in individuals with higher common betacoronavirus (ßCoV) antibody titers. Since antibody titers decline over time after CCV infections, individuals in our cohort with higher ßCoV antibody titers were more likely recently infected with common ßCoVs compared to individuals with lower antibody titers. Therefore, our data suggest that recent ßCoV infections potentially limit the severity of SARS-CoV-2 infections through mechanisms that do not involve cross-reactive antibodies. Our data are consistent with the emerging hypothesis that cellular immune responses elicited by recent common ßCoV infections transiently reduce disease severity following SARS-CoV-2 infections.

6.
AIDS Behav ; 25(7): 2230-2239, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33449236

RESUMO

Using a mobile research facility, we enrolled 141 opioid users from a neighborhood of Philadelphia, an urban epicenter of the opioid epidemic. Nearly all (95.6%) met DSM-5 criteria for severe opioid use disorder. The prevalence of HIV infection (8.5%) was more than seven times that found in the general population of the city. Eight of the HIV-positive participants (67.0%) reported receiving antiretroviral treatment but almost all of them had unsuppressed virus (87.5%). The majority of participants (57.4%) reported symptoms consistent with major depressive disorder. Severe economic distress (60.3%) and homelessness were common (57%). Polysubstance use was nearly universal, 72.1% had experienced multiple overdoses and prior medication for opioid use disorder (MOUD) treatment episodes (79.9%), but few currently engaged in addiction care. The prevalence, multiplicity and severity of chronic health and socioeconomic problems highlight consequences of the current opioid epidemic and underscore the urgent need to develop integrated models of treatment.


RESUMEN: Utilizando un Centro de Investigación Móvil, inscribimos a 141 usuarios de opioides del vecindario de Filadelfia, un epicentro urbano de la epidemia de opioides. Casi todos (95,6%) cumplieron con los criterios del DSM-5 para el trastorno del uso severo del consumo de opioides. La prevalencia de la infección de VIH (8,5%) fue másﹶ de 7 veces superior a las encontrada en la población general de la ciudad. Ocho de los participantes con VIH positivo (67,0%) reportaron haber recibido tratamiento antirretroviral pero casi todos tuvieron virus no suprimido (87,5%). La mayoría de los participantes (57,4%) informaron síntomas compatibles con el Desorden Depresivo Mayor. La angustia severa por lo económico (60,3%) y las personas sin hogar fueron comunes (57%). El uso de múltiples sustancias fue casi universal, el 721% había experimentado múltiples sobredosis y previos medicamentos para el tratamiento del trastorno por consumo de opioides (MOUD) (79,9%), pero muy pocos estaban comprometidos con la atención a las adicciones. La prevalencia, la multiplicidad y la seriedad de los problemas de salud crónica y los problemas socioeconómicos destacan las consecuencias de la actual epidemia de opioides y subrayan la urgente necesidad de desarrollar nuevos modelos de tratamiento integrados.


Assuntos
Buprenorfina , Transtorno Depressivo Maior , Infecções por HIV , Alcaloides Opiáceos , Transtornos Relacionados ao Uso de Opioides , Analgésicos Opioides/uso terapêutico , Buprenorfina/uso terapêutico , Depressão , Transtorno Depressivo Maior/tratamento farmacológico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Alcaloides Opiáceos/uso terapêutico , Epidemia de Opioides , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Philadelphia
7.
AIDS Behav ; 22(4): 1209-1216, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28744666

RESUMO

This study aimed to identify patients' physical and psychosocial experiences of an investigational long-acting injectable PrEP product to aid in the development of patient and provider education materials. Twenty-eight participants of a Phase 2 safety, tolerability, and acceptability study of long-acting integrase inhibitor cabotegravir (CAB-LA) were interviewed on their physical and psychosocial experiences of the injections. Five themes emerged through a framework analysis on these interview transcripts: (1) injection-related pain is highly variable across individuals; (2) pain is more impactful after the injections than during; (3) patient anxiety is critical, but does not determine the experience of injections and decreases over time; (4) intimacy and awkwardness of gluteal injections impacts patients' experiences; (5) patient education and care strategies can mitigate the above factors. These findings can inform further sociobehavioral research within Phase 3 efficacy trials of CAB-LA, as well as patient education and provider guidance for future injectable PrEP products.


Assuntos
Infecções por HIV/prevenção & controle , Inibidores de Integrase/administração & dosagem , Aceitação pelo Paciente de Cuidados de Saúde , Educação de Pacientes como Assunto , Profilaxia Pré-Exposição/métodos , Piridonas/administração & dosagem , Adulto , Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/tratamento farmacológico , Homossexualidade Masculina , Humanos , Injeções Intramusculares , Entrevistas como Assunto , Masculino , Pesquisa Qualitativa
8.
Vaccine ; 35(27): 3498-3505, 2017 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-28526330

RESUMO

OBJECTIVE: To compare the use of four different social media sites to recruit men who have sex with men (MSM) and transgender women to a phase 2b HIV prevention vaccine trial, HVTN 505. DESIGN: Retrospective, observational study. METHODS: The University of Pennsylvania HIV Vaccine Trials Unit (Penn HVTU) employed street outreach and online recruitment methods to recruit participants for HVTN 505 using a combination of national recruitment images/messages with Philadelphia-specific language and imagery. We compared the efficiency (number of enrolled participants per number of completed phone screens) and effectiveness (number of enrolled participants per time interval employed) of each strategy, as well as the demographics and risk behaviors of the populations. RESULTS: Online recruitment strategies populated 37% (71/191) of trial participants at our site. Among the four social media strategies employed, 45.1% (32/71) were enrolled through Facebook, 16.9% (12/71) through Craigslist, 15.5% (11/71) through a web-based marketing company (WBMC), and 22.5% (16/71) via GRINDR. The number of participants enrolled per month of strategy and the months the strategy was employed were Facebook - 32(33months), Craigslist - 12(33months), WBMC - 11(6months), and GRINDR - 16(0.56months). In-person and online recruitment strategies yielded participants of similar demographics and levels of risk behavior. CONCLUSION: Use of several social media recruitment modalities produced large numbers of MSM engaging in high risk behavior and willing to participate in an HIV prevention vaccine trial. In comparison to other social media and online strategies, recruitment via GRINDR was the most effective.


Assuntos
Vacinas contra a AIDS/imunologia , Ensaios Clínicos Fase II como Assunto , Transmissão de Doença Infecciosa/prevenção & controle , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Seleção de Pacientes , Mídias Sociais/estatística & dados numéricos , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Philadelphia , Estudos Retrospectivos , Adulto Jovem
9.
J Urban Health ; 92(3): 572-83, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25743100

RESUMO

Limited data are available on the longitudinal occurrence of syndemic factors among women at risk for HIV infection in the USA and how these factors relate to sexual risk over time. HVTN 906 was a longitudinal study enrolling 799 HIV-uninfected women in three cities. Assessments were done at baseline, 6, 12, and 18 months to assess syndemic factors (low education, low income, unemployment, lack of health insurance, housing instability, substance use, heavy alcohol use, partner violence, incarceration) and sexual risk outcomes. For each sexual risk outcome, a GEE model was fit with syndemic factors or syndemic score (defined as sum of binary syndemics, ranging from 0 to 9), visit, study site, age and race/ethnicity as predictors to examine the multivariable association between syndemic factors and outcomes over time. Odds of unprotected sex while drunk or high were significantly higher when women reported lack of health insurance, substance and heavy alcohol use and partner violence. Housing instability, substance and heavy alcohol use, partner violence and recent incarceration were associated with higher odds of having multiple sexual partners. Odds of sex exchange were significantly higher in the presence of unemployment, housing instability, low education, lack of health insurance, substance and heavy alcohol use, partner violence and incarceration. Housing instability, substance and heavy alcohol use, and partner violence were significantly associated with higher odds of unprotected anal sex. Odds of having a recent STI were significantly higher when women reported housing instability and partner violence. There were significantly higher odds of the reporting of any risk outcomes during follow-up with higher syndemic score. This study highlights a group of women experiencing multiple poor social and health outcomes who need to be the focus of comprehensive interventions.


Assuntos
Infecções por HIV/etiologia , Sexo sem Proteção/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adolescente , Adulto , Feminino , Humanos , Violência por Parceiro Íntimo/estatística & dados numéricos , Estudos Longitudinais , Pessoa de Meia-Idade , Fatores de Risco , Fatores Socioeconômicos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Estados Unidos/epidemiologia , Adulto Jovem
10.
J Acquir Immune Defic Syndr ; 63(2): 239-44, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23446497

RESUMO

BACKGROUND: Identifying cohorts of US women with HIV infection rates sufficient for inclusion in vaccine efficacy trials has been challenging. Using geography and sexual network characteristics to inform recruitment strategies, HVTN 906 determined the feasibility of recruiting a cohort of women at high risk for HIV acquisition. METHODS: HIV uninfected women who reported unprotected sex in the prior 6 months, resided or engaged in risk behavior in local geographical high-risk pockets and/or had a male partner who had been incarcerated, injected drugs, or had concurrent partners were eligible. Behavioral risk assessment, HIV counseling and testing, and pregnancy testing were done at baseline, 6, 12, and 18 months. RESULTS: Among 799 women, 71% were from local high-risk pockets and had high-risk male partners. Median age was 37 years; 79% were Black; and 15% Latina. Over half (55%) reported a new partner in the prior 6 months, 57% reported a male partner who had concurrent female sexual partners, and 37% reported a male partner who had been incarcerated. Retention at 18 months was 79.5%. Annual pregnancy incidence was 12%. Annual HIV incidence was 0.31% (95% confidence interval: 0.06% to 0.91%). Risk behaviors decreased between screening and 6 months with smaller changes thereafter. DISCUSSION: This cohort of women recruited using new strategies based on geography and sexual network characteristics did not have an HIV incidence high enough for HIV vaccine efficacy trials, despite high baseline levels of risk and a high pregnancy rate. New strategies to identify cohorts of US women for efficacy trials are needed.


Assuntos
Vacinas contra a AIDS/uso terapêutico , Ensaios Clínicos como Assunto , Infecções por HIV/prevenção & controle , Seleção de Pacientes , Adulto , Estudos de Coortes , Estudos de Viabilidade , Feminino , Infecções por HIV/epidemiologia , Humanos , Gravidez , Assunção de Riscos , Parceiros Sexuais , Inquéritos e Questionários , Estados Unidos/epidemiologia , Sexo sem Proteção , Adulto Jovem
11.
AIDS Behav ; 17(2): 760-72, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23090677

RESUMO

Enrollment of US women with sufficient risk of HIV infection into HIV vaccine efficacy trials has proved challenging. A cohort of 799 HIV-negative women, aged 18-45, recruited from three US cities was enrolled to assess recruitment strategies based on geographic risk pockets, social and sexual networks and occurrence of sexual concurrency and to assess HIV seroincidence during follow-up (to be reported later). Among enrolled women, 90 % lived or engaged in risk behaviors within a local risk pocket, 64 % had a male partner who had concurrent partners and 50 % had a male partner who had been recently incarcerated. Nearly half (46 %) were recruited through peer referral. At enrollment, 86 % of women said they were willing to participate in a vaccine efficacy trial. Results indicate that participant and partner risk behaviors combined with a peer referral recruitment strategy may best identify an at-risk cohort willing to participate in future trials.


Assuntos
Vacinas contra a AIDS , Infecções por HIV/epidemiologia , Participação do Paciente/estatística & dados numéricos , Seleção de Pacientes , Comportamento Sexual/estatística & dados numéricos , Adolescente , Adulto , Chicago/epidemiologia , Estudos de Viabilidade , Feminino , Infecções por HIV/prevenção & controle , Infecções por HIV/psicologia , Humanos , Pessoa de Meia-Idade , Cidade de Nova Iorque/epidemiologia , Participação do Paciente/psicologia , Philadelphia/epidemiologia , Estudos Prospectivos , Fatores de Risco , Assunção de Riscos , Comportamento Sexual/psicologia , Parceiros Sexuais/psicologia , Inquéritos e Questionários , População Urbana
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