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1.
J Infect Dis ; 225(7): 1124-1128, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34792136

RESUMO

Individuals on immunosuppressive (IS) therapy have increased mortality from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and delayed viral clearance may lead to new viral variants. IS therapy reduces antibody responses following coronavirus disease 2019 (COVID-19) messenger RNA (mRNA) vaccination; however, a comprehensive assessment of vaccine immunogenicity is lacking. Here we show that IS therapy reduced neutralizing, binding, and nonneutralizing antibody functions in addition to CD4 and CD8 T-cell interferon-γ responses following COVID-19 mRNA vaccination compared to immunocompetent individuals. Moreover, IS therapy reduced cross-reactivity against SARS-CoV-2 variants. These data suggest that the standard COVID-19 mRNA vaccine regimens will likely not provide optimal protection in immunocompromised individuals.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Imunogenicidade da Vacina , RNA Mensageiro , Vacinas Sintéticas , Vacinas de mRNA
2.
J Virol ; 95(14): e0040421, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-33893169

RESUMO

Emerging SARS-CoV-2 variants of concern that overcome natural and vaccine-induced immunity threaten to exacerbate the COVID-19 pandemic. Increasing evidence suggests that neutralizing antibody (NAb) responses are a primary mechanism of protection against infection. However, little is known about the extent and mechanisms by which natural immunity acquired during the early COVID-19 pandemic confers cross-neutralization of emerging variants. In this study, we investigated cross-neutralization of the B.1.1.7 and B.1.351 SARS-CoV-2 variants in a well-characterized cohort of early pandemic convalescent subjects. We observed modestly decreased cross-neutralization of B.1.1.7 but a substantial 4.8-fold reduction in cross-neutralization of B.1.351. Correlates of cross-neutralization included receptor binding domain (RBD) and N-terminal domain (NTD) binding antibodies, homologous NAb titers, and membrane-directed T cell responses. These data shed light on the cross-neutralization of emerging variants by early pandemic convalescent immune responses. IMPORTANCE Widespread immunity to SARS-CoV-2 will be necessary to end the COVID-19 pandemic. NAb responses are a critical component of immunity that can be stimulated by natural infection as well as vaccines. However, SARS-CoV-2 variants are emerging that contain mutations in the spike gene that promote evasion from NAb responses. These variants may therefore delay control of the COVID-19 pandemic. We studied whether NAb responses from early COVID-19 convalescent patients are effective against the two SARS-CoV-2 variants, B.1.1.7 and B.1.351. We observed that the B.1.351 variant demonstrates significantly reduced susceptibility to early pandemic NAb responses. We additionally characterized virological, immunological, and clinical features that correlate with cross-neutralization. These studies increase our understanding of emerging SARS-CoV-2 variants.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/epidemiologia , COVID-19/imunologia , Pandemias , SARS-CoV-2/imunologia , Adulto , Reações Cruzadas , Humanos , Masculino
3.
JAMA ; 325(23): 2370-2380, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33983379

RESUMO

Importance: Pregnant women are at increased risk of morbidity and mortality from COVID-19 but have been excluded from the phase 3 COVID-19 vaccine trials. Data on vaccine safety and immunogenicity in these populations are therefore limited. Objective: To evaluate the immunogenicity of COVID-19 messenger RNA (mRNA) vaccines in pregnant and lactating women, including against emerging SARS-CoV-2 variants of concern. Design, Setting, and Participants: An exploratory, descriptive, prospective cohort study enrolled 103 women who received a COVID-19 vaccine from December 2020 through March 2021 and 28 women who had confirmed SARS-CoV-2 infection from April 2020 through March 2021 (the last follow-up date was March 26, 2021). This study enrolled 30 pregnant, 16 lactating, and 57 neither pregnant nor lactating women who received either the mRNA-1273 (Moderna) or BNT162b2 (Pfizer-BioNTech) COVID-19 vaccines and 22 pregnant and 6 nonpregnant unvaccinated women with SARS-CoV-2 infection. Main Outcomes and Measures: SARS-CoV-2 receptor binding domain binding, neutralizing, and functional nonneutralizing antibody responses from pregnant, lactating, and nonpregnant women were assessed following vaccination. Spike-specific T-cell responses were evaluated using IFN-γ enzyme-linked immunospot and multiparameter intracellular cytokine-staining assays. Humoral and cellular immune responses were determined against the original SARS-CoV-2 USA-WA1/2020 strain as well as against the B.1.1.7 and B.1.351 variants. Results: This study enrolled 103 women aged 18 to 45 years (66% non-Hispanic White) who received a COVID-19 mRNA vaccine. After the second vaccine dose, fever was reported in 4 pregnant women (14%; SD, 6%), 7 lactating women (44%; SD, 12%), and 27 nonpregnant women (52%; SD, 7%). Binding, neutralizing, and functional nonneutralizing antibody responses as well as CD4 and CD8 T-cell responses were present in pregnant, lactating, and nonpregnant women following vaccination. Binding and neutralizing antibodies were also observed in infant cord blood and breast milk. Binding and neutralizing antibody titers against the SARS-CoV-2 B.1.1.7 and B.1.351 variants of concern were reduced, but T-cell responses were preserved against viral variants. Conclusion and Relevance: In this exploratory analysis of a convenience sample, receipt of a COVID-19 mRNA vaccine was immunogenic in pregnant women, and vaccine-elicited antibodies were transported to infant cord blood and breast milk. Pregnant and nonpregnant women who were vaccinated developed cross-reactive antibody responses and T-cell responses against SARS-CoV-2 variants of concern.


Assuntos
Anticorpos Antivirais/sangue , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Sangue Fetal/imunologia , Imunogenicidade da Vacina , Leite Humano/imunologia , SARS-CoV-2/imunologia , Vacina de mRNA-1273 contra 2019-nCoV , Adulto , Anticorpos Neutralizantes/sangue , Vacina BNT162 , Reações Cruzadas/imunologia , Feminino , Humanos , Imunoensaio , Lactação , Leucócitos Mononucleares/fisiologia , Pessoa de Meia-Idade , Gravidez/imunologia , Estudos Prospectivos , Linfócitos T/imunologia , Vacinas Sintéticas/imunologia , Adulto Jovem , Vacinas de mRNA
5.
Reprod Sci ; 30(9): 2655-2664, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36749459

RESUMO

Conventional and regulatory T cells (Treg) are dynamic mediators of maternal immune tolerance to the developing feto-placental unit. Functional evaluation of T cells at the maternal-fetal interface is crucial to elucidate the immunologic basis of obstetric complications. Our objective was to define the T cell phenotype and function of uterine intervillous blood (IVB) in pregnancy with and without preeclampsia. We hypothesize that preeclampsia is associated with impaired immune tolerance and a pro-inflammatory uterine T cell microenvironment. In this cross-sectional study, maternal peripheral blood (PB) and uterine IVB (obtained from the surgical sponge used to clean the placental bed during cesarean delivery) were collected from participants with and without preeclampsia. Proportion, activation, and cytokine production of T cell subsets were quantified by flow cytometry. T cell parameters were compared by tissue source and by preeclampsia status. Sixty participants, 26 with preeclampsia, were included. Induced Treg made up a greater proportion of IVB T cells compared to PB and had greater cytokine-producing capacity. Preeclampsia was associated with increased ratio of pro-inflammatory IL-17α to suppressive IL-10 cytokine production by CD4 T cell subsets in IVB, but not in PB. Human uterine IVB is composed of activated, cytokine-producing T cell subsets distinct from maternal PB. Preeclampsia is associated with a pro-inflammatory IVB profile, with increased IL-17α /IL-10 ratio in all CD4 T cell subsets. IVB sampling is a useful tool for investigating human T cell biology at the maternal-fetal interface that may inform immunotherapeutic strategies for preeclampsia.


Assuntos
Placenta , Pré-Eclâmpsia , Humanos , Gravidez , Feminino , Interleucina-10 , Estudos Transversais , Linfócitos T Reguladores , Citocinas
6.
Lancet HIV ; 10(2): e84-e96, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36565708

RESUMO

BACKGROUND: Although gay, bisexual, and other cisgender men who have sex with men (MSM) and transgender women have the highest HIV burden in Latin America, pre-exposure prophylaxis (PrEP) implementation is poor. We aimed to assess the feasibility of same-day oral PrEP delivery in Brazil, Mexico, and Peru. METHODS: Implementation PrEP (ImPrEP) was a prospective, single-arm, open-label, multicentre PrEP implementation study conducted in Brazil (14 sites), Mexico (four sites), and Peru (ten sites). MSM and transgender women were eligible to participate if they were aged 18 years or older, HIV-negative, and reported one or more prespecified criteria. Enrolled participants received same-day initiation of daily oral PrEP (tenofovir disoproxil fumarate [300 mg] coformulated with emtricitabine [200 mg]). Follow-up visits were scheduled at week 4 and quarterly thereafter. We used logistic regression models to identify factors associated with early loss to follow-up (not returning after enrolment), PrEP adherence (medication possession ratio ≥0·6), and long-term PrEP engagement (attending three or more visits within 52 weeks). This study is registered at the Brazilian Registry of Clinical Trials, U1111-1217-6021. FINDINGS: From Feb 6, 2018, to June 30, 2021, 9979 participants were screened and 9509 were enrolled (Brazil n=3928, Mexico n=3288, and Peru n=2293). 543 (5·7%) participants were transgender women, 8966 (94·3%) were cisgender men, and 2481 (26·1%) were aged 18-24 years. There were 12 185·25 person-years of follow-up. 795 (8·4%) of 9509 participants had early loss to follow-up, 6477 (68·1%) of 9509 were adherent to PrEP, and 5783 (70·3%) of 8225 had long-term PrEP engagement. Transgender women (adjusted odds ratio 1·60, 95% CI 1·20-2·14), participants aged 18-24 years (1·80, 1·49-2·18), and participants with primary education (2·18, 1·29-3·68) had increased odds of early loss to follow-up. Transgender women (0·56, 0·46-0·70), participants aged 18-24 years (0·52, 0·46-0·58), and those with primary education (0·60, 0·40-0·91) had lower odds of PrEP adherence. Transgender women (0·56, 0·45-0·71), participants aged 18-24 years (0·56, 0·49-0·64), and those with secondary education (0·74, 0·68-0·86) had lower odds of long-term PrEP engagement. HIV incidence was 0·85 per 100 person-years (95% CI 0·70-1·03) and was higher for transgender women, participants from Peru, those aged 18-24 years, Black and mixed-race participants, and participants who were non-adherent to PrEP. INTERPRETATION: Same-day oral PrEP is feasible for MSM and transgender women in Latin America. Social and structural determinants of HIV vulnerability need to be addressed to fully achieve the benefits of PrEP. FUNDING: Unitaid, WHO, and Ministries of Health in Brazil, Mexico, and Peru. TRANSLATIONS: For the Portuguese and Spanish translations of the abstract see Supplementary Materials section.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Profilaxia Pré-Exposição , Minorias Sexuais e de Gênero , Pessoas Transgênero , Masculino , Humanos , Feminino , Homossexualidade Masculina , Brasil/epidemiologia , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Infecções por HIV/tratamento farmacológico , Fármacos Anti-HIV/uso terapêutico , Peru/epidemiologia , México/epidemiologia , Estudos Prospectivos
7.
Contraception ; 114: 61-66, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35671842

RESUMO

OBJECTIVE: Prior work shows that ads related to abortion services often feature crisis pregnancy centers instead of abortion providers. We investigated whether a change in Google's advertising policy that required advertisers to disclose whether they provided abortion services increased the proportion of ads facilitating abortion self-referral. STUDY DESIGN: We used a standardized protocol to search online for abortion services before, during, and after the policy change; we performed searches in August 2016 to June 2017, June 2019, and October 2019, respectively, using Google, Bing, and Yahoo search engines. We performed searches for the 25 most populous U.S. cities and the 43 state capitals not already included. We classified up to the first 5 ads as facilitating abortion referral, hindering abortion referral, or providing neutral content. We compared search engine results using a chi-square test. RESULTS: Among ads returned by Google, those shown after the policy change were significantly more likely to facilitate abortion self-referral (66.7% vs. 44.2%; p = 0.003) and slightly less likely to hinder abortion self-referral (33.3% vs. 40.6%; p = 0.33) compared to before the change. These findings were reversed for ads shown by Bing and Yahoo; ads returned after the change were significantly less likely to facilitate abortion self-referral (24.6% vs. 32.8%; p = 0.01) and significantly more likely to hinder self-referral (28.3% vs. 21.6%; p = 0.03) compared to before the change. CONCLUSION: A policy requiring advertisers to disclose whether they provide abortion services was associated with increasing the proportion of ads facilitating self-referral. Similar policies should be considered by all search engines. IMPLICATIONS: While the internet is a convenient source of information that individuals often use to locate abortion providers, the information may not actually lead searchers to services. Search engines should consider restricting abortion-related advertising to organizations that provide abortion services in order to ensure that individuals searching online for abortion services are able to locate services in a direct and timely manner.


Assuntos
Aborto Induzido , Publicidade , Aborto Induzido/métodos , Feminino , Humanos , Internet , Políticas , Gravidez , Encaminhamento e Consulta , Ferramenta de Busca
8.
Cureus ; 14(7): e27100, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36000127

RESUMO

BACKGROUND: We assessed understanding of the obstetric consent form between patients with English and Spanish language preference. METHODS: This observational study included pregnant patients who identified as Hispanic/Latinx with English or Spanish language preference (defined as what language the patient prefers to receive healthcare information) and prenatal care providers at a large academic medical center from 2018 to 2021. Patient demographics, language preference, literacy, numeracy, acculturation, comprehension of the obstetric consent, and provider explanations were collected. RESULTS: We report descriptive statistics and thematic analysis with an inductive approach from 30 patients with English preference, 10 with Spanish preference, and 23 providers. The English group demonstrated 72% median correct responses about the consent form; the Spanish group demonstrated 61% median correct responses. Regardless of language, the participants demonstrated limited understanding of certain topics, such as risks of cesarean birth. DISCUSSION: Overall comprehension of key information in an obstetric consent form was low, with differences in language groups, which highlights opportunities for improvements in communication across language barriers. Innovations in the communication of critical pregnancy information for patients with limited English proficiency need to be developed and tested.

9.
Sci Transl Med ; 14(641): eabn6150, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35258323

RESUMO

Breakthrough infections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants have been reported frequently in vaccinated individuals with waning immunity. In particular, a cluster of over 1000 infections with the SARS-CoV-2 delta variant was identified in a predominantly fully vaccinated population in Provincetown, Massachusetts in July 2021. In this study, vaccinated individuals who tested positive for SARS-CoV-2 (n = 16) demonstrated substantially higher serum antibody responses than vaccinated individuals who tested negative for SARS-CoV-2 (n = 23), including 32-fold higher binding antibody titers and 31-fold higher neutralizing antibody titers against the SARS-CoV-2 delta variant. Vaccinated individuals who tested positive also showed higher mucosal antibody responses in nasal secretions and higher spike protein-specific CD8+ T cell responses in peripheral blood than did vaccinated individuals who tested negative. These data demonstrate that fully vaccinated individuals developed robust anamnestic antibody and T cell responses after infection with the SARS-CoV-2 delta variant. Moreover, these findings suggest that population immunity will likely increase over time by a combination of widespread vaccination and breakthrough infections.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Formação de Anticorpos , Humanos
10.
J Perinatol ; 41(12): 2754-2760, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34983936

RESUMO

OBJECTIVE: Compare the incidence of hypoglycemia in neonates born to patients with diabetes, based on last maternal glucose before delivery. STUDY DESIGN: Cohort of singleton births from individuals with pregestational and gestational diabetes (GDM) from 2017 to 2019. RESULTS: We included 853 deliveries. Maternal hyperglycemia before delivery was associated with 1.8-fold greater risk of neonatal hypoglycemia (glucose < 45 mg/dL) in patients with GDM on medication (adjusted risk ratio (aRR): 1.8; 95% CI: 1.1-2.7), compared with euglycemia. This association was not seen in diet-controlled GDM (0.5; 0.23-1.1), nor in Type 1 (1.1; 0.88-1.4), or Type 2 pregestational diabetes (1.1; 0.61-1.9). Further, pregestational diabetes, compared to GDM, regardless of intrapartum maternal glucose control, was associated with neonatal hypoglycemia and NICU admission. CONCLUSION: Maternal hyperglycemia before delivery only carried a higher risk of neonatal hypoglycemia in those with GDM on medications. Other interventions to reduce neonatal hypoglycemia are needed.


Assuntos
Diabetes Gestacional , Hipoglicemia , Doenças do Recém-Nascido , Glicemia , Diabetes Gestacional/tratamento farmacológico , Diabetes Gestacional/epidemiologia , Feminino , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemia/epidemiologia , Recém-Nascido , Doenças do Recém-Nascido/epidemiologia , Gravidez , Estudos Retrospectivos
11.
medRxiv ; 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34704104

RESUMO

BACKGROUND: A cluster of over a thousand infections with the SARS-CoV-2 delta variant was identified in a predominantly fully vaccinated population in Provincetown, Massachusetts in July 2021. Immune responses in breakthrough infections with the SARS-CoV-2 delta variant remain to be defined. METHODS: Humoral and cellular immune responses were assessed in 35 vaccinated individuals who were tested for SARS-CoV-2 in the Massachusetts Department of Public Health outbreak investigation. RESULTS: Vaccinated individuals who tested positive for SARS-CoV-2 demonstrated substantially higher antibody responses than vaccinated individuals who tested negative for SARS-CoV-2, including 28-fold higher binding antibody titers and 34-fold higher neutralizing antibody titers against the SARS-CoV-2 delta variant. Vaccinated individuals who tested positive also showed 4.4-fold higher Spike-specific CD8+ T cell responses against the SARS-CoV-2 delta variant than vaccinated individuals who tested negative. CONCLUSIONS: Fully vaccinated individuals developed robust anamnestic antibody and T cell responses following infection with the SARS-CoV-2 delta variant. These data suggest important immunologic benefits of vaccination in the context of breakthrough infections.

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