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2.
PLoS Med ; 19(10): e1003979, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36301821

RESUMEN

BACKGROUND: Vaccines can be less immunogenic in people living with HIV (PLWH), but for SARS-CoV-2 vaccinations this is unknown. In this study we set out to investigate, for the vaccines currently approved in the Netherlands, the immunogenicity and reactogenicity of SARS-CoV-2 vaccinations in PLWH. METHODS AND FINDINGS: We conducted a prospective cohort study to examine the immunogenicity of BNT162b2, mRNA-1273, ChAdOx1-S, and Ad26.COV2.S vaccines in adult PLWH without prior COVID-19, and compared to HIV-negative controls. The primary endpoint was the anti-spike SARS-CoV-2 IgG response after mRNA vaccination. Secondary endpoints included the serological response after vector vaccination, anti-SARS-CoV-2 T-cell response, and reactogenicity. Between 14 February and 7 September 2021, 1,154 PLWH (median age 53 [IQR 44-60] years, 85.5% male) and 440 controls (median age 43 [IQR 33-53] years, 28.6% male) were included in the final analysis. Of the PLWH, 884 received BNT162b2, 100 received mRNA-1273, 150 received ChAdOx1-S, and 20 received Ad26.COV2.S. In the group of PLWH, 99% were on antiretroviral therapy, 97.7% were virally suppressed, and the median CD4+ T-cell count was 710 cells/µL (IQR 520-913). Of the controls, 247 received mRNA-1273, 94 received BNT162b2, 26 received ChAdOx1-S, and 73 received Ad26.COV2.S. After mRNA vaccination, geometric mean antibody concentration was 1,418 BAU/mL in PLWH (95% CI 1322-1523), and after adjustment for age, sex, and vaccine type, HIV status remained associated with a decreased response (0.607, 95% CI 0.508-0.725, p < 0.001). All controls receiving an mRNA vaccine had an adequate response, defined as >300 BAU/mL, whilst in PLWH this response rate was 93.6%. In PLWH vaccinated with mRNA-based vaccines, higher antibody responses were predicted by CD4+ T-cell count 250-500 cells/µL (2.845, 95% CI 1.876-4.314, p < 0.001) or >500 cells/µL (2.936, 95% CI 1.961-4.394, p < 0.001), whilst a viral load > 50 copies/mL was associated with a reduced response (0.454, 95% CI 0.286-0.720, p = 0.001). Increased IFN-γ, CD4+ T-cell, and CD8+ T-cell responses were observed after stimulation with SARS-CoV-2 spike peptides in ELISpot and activation-induced marker assays, comparable to controls. Reactogenicity was generally mild, without vaccine-related serious adverse events. Due to the control of vaccine provision by the Dutch National Institute for Public Health and the Environment, there were some differences between vaccine groups in the age, sex, and CD4+ T-cell counts of recipients. CONCLUSIONS: After vaccination with BNT162b2 or mRNA-1273, anti-spike SARS-CoV-2 antibody levels were reduced in PLWH compared to HIV-negative controls. To reach and maintain the same serological responses as HIV-negative controls, additional vaccinations are probably required. TRIAL REGISTRATION: The trial was registered in the Netherlands Trial Register (NL9214). https://www.trialregister.nl/trial/9214.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Infecciones por VIH , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ad26COVS1 , Anticuerpos Antivirales , Vacuna BNT162 , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19/inmunología , Infecciones por VIH/inmunología , Inmunogenicidad Vacunal , Inmunoglobulina G , Países Bajos/epidemiología , Estudios Prospectivos , ARN Mensajero , SARS-CoV-2 , Vacunas de ARNm
3.
PLoS One ; 10(2): e0118181, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25700108

RESUMEN

Toll-like receptors (TLR) and the downstream adaptor protein MyD88 are considered crucial for protective immunity during bacterial infections. Streptococcus (S.) pneumoniae is a human respiratory pathogen and a large majority of clinical pneumococcal isolates expresses an external polysaccharide capsule. We here sought to determine the role of pneumococcal capsule in MyD88-mediated antibacterial defense during S. pneumonia pneumonia. Wild type (WT) and Myd88(-/-) mice were inoculated intranasally with serotype 2 S. pneumoniae D39 or with an isogenic capsule locus deletion mutant (D39∆cps), and analysed for bacterial outgrowth and inflammatory responses in the lung. As compared to WT mice, Myd88(-/-) mice infected with D39 demonstrated a modestly impaired bacterial clearance accompanied by decreased inflammatory responses in the lung. Strikingly, while WT mice rapidly cleared D39∆cps, Myd88(-/-) mice showed 105-fold higher bacterial burdens in their lungs and dissemination to blood 24 hours after infection. These data suggest that the pneumococcal capsule impairs recognition of TLR ligands expressed by S. pneumoniae and thereby partially impedes MyD88-mediated antibacterial defense.


Asunto(s)
Cápsulas Bacterianas/inmunología , Factor 88 de Diferenciación Mieloide/genética , Neumonía Bacteriana/inmunología , Polisacáridos Bacterianos/inmunología , Streptococcus pneumoniae/inmunología , Animales , Cápsulas Bacterianas/genética , Eliminación de Gen , Ratones , Ratones Endogámicos C57BL , Factor 88 de Diferenciación Mieloide/inmunología
4.
BMC Infect Dis ; 12: 139, 2012 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-22721450

RESUMEN

BACKGROUND: Asplenic individuals are susceptible for overwhelming infection with Streptococcus pneumoniae, carrying a high mortality. Although Toll-like receptor (TLR)-2 is considered the major receptor for Gram-positive bacteria in innate immunity, it does not play a major role in host defense against pneumococcal pneumonia. We wanted to investigate if in absence of an intact spleen as a first line of defense, the role of TLR2 during pneumococcal pneumonia becomes more significant, thereby explaining its insignificant role during infections in immune competent hosts. METHODS: We intranasally infected splenectomized wildtype (WT), TLR2 knock-out (KO) and TLR2/4 double KO mice with either serotype 2 or 3 S. pneumoniae. RESULTS: There were no differences between asplenic WT and TLR2KO mice of bacterial loads in lung homogenates and blood, cytokine and chemokine levels in the lungs, and lung pathology scores. TLR2/4 double KO mice were not impaired in bacterial control as well, which indicates that besides the interaction between S. pneumoniae and TLR2, the interaction between pneumolysin and TLR4 does not stimulate antibacterial defense in the asplenic host either. CONCLUSIONS: These results argue against a significant role of TLR2 in host defense during S. pneumoniae pneumonia in the asplenic state. Therefore, other components can provide sufficient backup mechanisms for TLR2 deficiency in the defense against intrapulmonary infections with S. pneumoniae of the otherwise immune competent host.


Asunto(s)
Neumonía Neumocócica/inmunología , Bazo/anomalías , Bazo/inmunología , Streptococcus pneumoniae/inmunología , Receptor Toll-Like 2/metabolismo , Animales , Carga Bacteriana , Pulmón/microbiología , Pulmón/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Esplenectomía , Receptor Toll-Like 2/genética , Receptor Toll-Like 2/inmunología , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/inmunología , Receptor Toll-Like 4/metabolismo
5.
J Infect Dis ; 205(12): 1849-57, 2012 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-22492852

RESUMEN

BACKGROUND: Streptococcus pneumoniae is the most common causative organism in community-acquired pneumonia. Pneumococci that try to invade the lower airways are recognized by innate immune cells through pattern recognition receptors, including Toll-like receptors 2, 4, and 9. Interleukin 1 (IL-1) receptor-associated kinase (IRAK)-M is a proximal inhibitor of Toll-like receptor signaling. METHODS: To determine the role of IRAK-M in host defense during pneumococcal pneumonia, IRAK-M- deficient and wild-type mice were intranasally infected with S. pneumoniae. RESULTS: IRAK-M-deficient mice demonstrated a reduced lethality after infection with S. pneumoniae via the airways. Whereas bacterial burdens were similar in IRAK-M-deficient and wild-type mice early (3 hours) after infection, from 24 hours onward the number of pneumococci recovered from lungs and distant body sites were 10-100-fold lower in the former mouse strain. The diminished bacterial growth and dissemination in IRAK-M-deficient mice were preceded by an increased early influx of neutrophils into lung tissue and elevated pulmonary levels of IL-1ß and CXCL1. IRAK-M deficiency did not influence bacterial growth after intravenous administration of S. pneumoniae. CONCLUSIONS: These data suggest that IRAK-M impairs host defense during pneumococcal pneumonia at the primary site of infection at least in part by inhibiting the early immune response.


Asunto(s)
Interacciones Huésped-Patógeno , Quinasas Asociadas a Receptores de Interleucina-1/metabolismo , Neumonía Neumocócica/inmunología , Neumonía Neumocócica/patología , Streptococcus pneumoniae/inmunología , Streptococcus pneumoniae/patogenicidad , Animales , Carga Bacteriana , Modelos Animales de Enfermedad , Humanos , Quinasas Asociadas a Receptores de Interleucina-1/deficiencia , Pulmón/microbiología , Ratones , Ratones Endogámicos C57BL
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