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1.
Nat Immunol ; 24(6): 966-978, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37248417

RESUMEN

High-risk groups, including Indigenous people, are at risk of severe COVID-19. Here we found that Australian First Nations peoples elicit effective immune responses to COVID-19 BNT162b2 vaccination, including neutralizing antibodies, receptor-binding domain (RBD) antibodies, SARS-CoV-2 spike-specific B cells, and CD4+ and CD8+ T cells. In First Nations participants, RBD IgG antibody titers were correlated with body mass index and negatively correlated with age. Reduced RBD antibodies, spike-specific B cells and follicular helper T cells were found in vaccinated participants with chronic conditions (diabetes, renal disease) and were strongly associated with altered glycosylation of IgG and increased interleukin-18 levels in the plasma. These immune perturbations were also found in non-Indigenous people with comorbidities, indicating that they were related to comorbidities rather than ethnicity. However, our study is of a great importance to First Nations peoples who have disproportionate rates of chronic comorbidities and provides evidence of robust immune responses after COVID-19 vaccination in Indigenous people.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Humanos , Vacuna BNT162 , COVID-19/prevención & control , Linfocitos T CD8-positivos , Australia/epidemiología , SARS-CoV-2 , Inmunoglobulina G , Anticuerpos Neutralizantes , Inmunidad , Anticuerpos Antivirales , Vacunación
2.
Immunity ; 55(7): 1299-1315.e4, 2022 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-35750048

RESUMEN

As the establishment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific T cell memory in children remains largely unexplored, we recruited convalescent COVID-19 children and adults to define their circulating memory SARS-CoV-2-specific CD4+ and CD8+ T cells prior to vaccination. We analyzed epitope-specific T cells directly ex vivo using seven HLA class I and class II tetramers presenting SARS-CoV-2 epitopes, together with Spike-specific B cells. Unvaccinated children who seroconverted had comparable Spike-specific but lower ORF1a- and N-specific memory T cell responses compared with adults. This agreed with our TCR sequencing data showing reduced clonal expansion in children. A strong stem cell memory phenotype and common T cell receptor motifs were detected within tetramer-specific T cells in seroconverted children. Conversely, children who did not seroconvert had tetramer-specific T cells of predominantly naive phenotypes and diverse TCRαß repertoires. Our study demonstrates the generation of SARS-CoV-2-specific T cell memory with common TCRαß motifs in unvaccinated seroconverted children after their first virus encounter.


Asunto(s)
COVID-19 , SARS-CoV-2 , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , Epítopos de Linfocito T , Humanos , Memoria Inmunológica , Receptores de Antígenos de Linfocitos T , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Glicoproteína de la Espiga del Coronavirus
3.
Immunity ; 54(5): 1066-1082.e5, 2021 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-33951417

RESUMEN

To better understand primary and recall T cell responses during coronavirus disease 2019 (COVID-19), it is important to examine unmanipulated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific T cells. By using peptide-human leukocyte antigen (HLA) tetramers for direct ex vivo analysis, we characterized CD8+ T cells specific for SARS-CoV-2 epitopes in COVID-19 patients and unexposed individuals. Unlike CD8+ T cells directed toward subdominant epitopes (B7/N257, A2/S269, and A24/S1,208) CD8+ T cells specific for the immunodominant B7/N105 epitope were detected at high frequencies in pre-pandemic samples and at increased frequencies during acute COVID-19 and convalescence. SARS-CoV-2-specific CD8+ T cells in pre-pandemic samples from children, adults, and elderly individuals predominantly displayed a naive phenotype, indicating a lack of previous cross-reactive exposures. T cell receptor (TCR) analyses revealed diverse TCRαß repertoires and promiscuous αß-TCR pairing within B7/N105+CD8+ T cells. Our study demonstrates high naive precursor frequency and TCRαß diversity within immunodominant B7/N105-specific CD8+ T cells and provides insight into SARS-CoV-2-specific T cell origins and subsequent responses.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , COVID-19/inmunología , Proteínas de la Nucleocápside de Coronavirus/inmunología , Epítopos Inmunodominantes/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , SARS-CoV-2/inmunología , Adulto , Anciano , Secuencias de Aminoácidos , Linfocitos T CD4-Positivos , Niño , Convalecencia , Proteínas de la Nucleocápside de Coronavirus/química , Epítopos de Linfocito T/química , Epítopos de Linfocito T/inmunología , Femenino , Humanos , Epítopos Inmunodominantes/química , Masculino , Persona de Mediana Edad , Fenotipo , Fosfoproteínas/química , Fosfoproteínas/inmunología , Receptores de Antígenos de Linfocitos T/química , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T alfa-beta/química , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/inmunología
4.
Immunol Cell Biol ; 101(4): 333-344, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36702633

RESUMEN

Central nervous system virus infections are a major cause of morbidity and mortality worldwide and a significant global public health concern. As in many tissues, inflammation and immune responses in the brain, despite their protective roles, can also be harmful. Control of brain inflammation is important in many neurological diseases from encephalitis to multiple sclerosis and neurogenerative disease. The suppressors of cytokine signaling (SOCS) proteins are a key mechanism controlling inflammatory and immune responses across all tissues including the brain. Using a mouse model system, we demonstrate that lack of SOCS4 results in changes in the pathogenesis and clinical outcome of a neurotropic virus infection. Relative to wild-type mice, SOCS4-deficient mice showed accelerated clearance of virus from the brain, lower levels of persisting viral RNA in the brain, increased neuroinflammation and more severe neuropathology. We conclude that, in the mouse brain, SOCS4 is a vital regulator of antiviral immunity that mediates the critical balance between immunopathology and virus persistence.


Asunto(s)
Citocinas , Encefalitis , Proteínas Supresoras de la Señalización de Citocinas , Animales , Ratones , Citocinas/inmunología , Encefalitis/inmunología , Encefalitis/virología , Inmunidad , Virus de los Bosques Semliki , Transducción de Señal , Proteínas Supresoras de la Señalización de Citocinas/genética , Proteínas Supresoras de la Señalización de Citocinas/metabolismo
5.
Immunol Cell Biol ; 101(10): 964-974, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37725525

RESUMEN

Indigenous peoples globally are at increased risk of COVID-19-associated morbidity and mortality. However, data that describe immune responses to SARS-CoV-2 infection in Indigenous populations are lacking. We evaluated immune responses in Australian First Nations peoples hospitalized with COVID-19. Our work comprehensively mapped out inflammatory, humoral and adaptive immune responses following SARS-CoV-2 infection. Patients were recruited early following the lifting of strict public health measures in the Northern Territory, Australia, between November 2021 and May 2022. Australian First Nations peoples recovering from COVID-19 showed increased levels of MCP-1 and IL-8 cytokines, IgG-antibodies against Delta-RBD and memory SARS-CoV-2-specific T cell responses prior to hospital discharge in comparison with hospital admission, with resolution of hyperactivated HLA-DR+ CD38+ T cells. SARS-CoV-2 infection elicited coordinated ASC, Tfh and CD8+ T cell responses in concert with CD4+ T cell responses. Delta and Omicron RBD-IgG, as well as Ancestral N-IgG antibodies, strongly correlated with Ancestral RBD-IgG antibodies and Spike-specific memory B cells. We provide evidence of broad and robust immune responses following SARS-CoV-2 infection in Indigenous peoples, resembling those of non-Indigenous COVID-19 hospitalized patients.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Australia , Inmunoglobulina G , Pueblos Indígenas , Inmunidad , Anticuerpos Antivirales
6.
PLoS Pathog ; 17(7): e1009759, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34320031

RESUMEN

The host response to SARS-CoV-2 infection provide insights into both viral pathogenesis and patient management. The host-encoded microRNA (miRNA) response to SARS-CoV-2 infection, however, remains poorly defined. Here we profiled circulating miRNAs from ten COVID-19 patients sampled longitudinally and ten age and gender matched healthy donors. We observed 55 miRNAs that were altered in COVID-19 patients during early-stage disease, with the inflammatory miR-31-5p the most strongly upregulated. Supervised machine learning analysis revealed that a three-miRNA signature (miR-423-5p, miR-23a-3p and miR-195-5p) independently classified COVID-19 cases with an accuracy of 99.9%. In a ferret COVID-19 model, the three-miRNA signature again detected SARS-CoV-2 infection with 99.7% accuracy, and distinguished SARS-CoV-2 infection from influenza A (H1N1) infection and healthy controls with 95% accuracy. Distinct miRNA profiles were also observed in COVID-19 patients requiring oxygenation. This study demonstrates that SARS-CoV-2 infection induces a robust host miRNA response that could improve COVID-19 detection and patient management.


Asunto(s)
Prueba de COVID-19/métodos , COVID-19/diagnóstico , COVID-19/genética , MicroARNs/genética , SARS-CoV-2 , Adulto , Anciano , Animales , COVID-19/sangre , Estudios de Casos y Controles , Diagnóstico Diferencial , Modelos Animales de Enfermedad , Femenino , Hurones , Expresión Génica , Interacciones Microbiota-Huesped/genética , Humanos , Subtipo H1N1 del Virus de la Influenza A , Estudios Longitudinales , Masculino , MicroARNs/sangre , Persona de Mediana Edad , Infecciones por Orthomyxoviridae/diagnóstico , Infecciones por Orthomyxoviridae/genética , Pandemias , Aprendizaje Automático Supervisado
7.
Sensors (Basel) ; 21(15)2021 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-34372367

RESUMEN

The paper presents a method and results of experimental testing of the stability of palletized cargo wrapped in stretch film in laboratory conditions and methods and parameterization of its application for proper cargo securing. Reduction of stretch film consumption is also significant for sustainable transport. It will contribute to the minimization of costs on a micro-scale (manufacturers and shippers) and a macro scale-a significant reduction in pollution of the environment and gas emissions by reducing stretch film production. The experiments have been performed following the requirements of EUMOS 40509 and 40511 standards. The proposed method of testing the stability of palletized cargo is based on tests performed on a laboratory test bench using FEF-200 sensors. The results of conducted experiments demonstrated that the selection of a proper stretch film and a cargo wrapping model could significantly reduce the risk of cargo damage through increasing cargo stabilizing forces and, at the same time, reducing stretch film consumption. The developed method can significantly reduce the cost of securing and concurrently assure required cargo security. This directly impacts the safety of all participants in the transport process in supply chains.


Asunto(s)
Transportes , Humanos
9.
Immunol Cell Biol ; 97(9): 840-852, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31335993

RESUMEN

The innate immune system is our first line of defense against viral pathogens. Host cell pattern recognition receptors sense viral components and initiate immune signaling cascades that result in the production of an array of cytokines to combat infection. Retinoic acid-inducible gene-I (RIG-I) is a pattern recognition receptor that recognizes viral RNA and, when activated, results in the production of type I and III interferons (IFNs) and the upregulation of IFN-stimulated genes. Ubiquitination of RIG-I by the E3 ligases tripartite motif-containing 25 (TRIM25) and Riplet is thought to be requisite for RIG-I activation; however, recent studies have questioned the relative importance of these two enzymes for RIG-I signaling. In this study, we show that deletion of Trim25 does not affect the IFN response to either influenza A virus (IAV), influenza B virus, Sendai virus or several RIG-I agonists. This is in contrast to deletion of either Rig-i or Riplet, which completely abrogated RIG-I-dependent IFN responses. This was consistent in both mouse and human cell lines, as well as in normal human bronchial cells. With most of the current TRIM25 literature based on exogenous expression, these findings provide critical evidence that Riplet, and not TRIM25, is required endogenously for the ubiquitination of RIG-I. Despite this, loss of TRIM25 results in greater susceptibility to IAV infection in vivo, suggesting that it may have an alternative role in host antiviral defense. This study refines our understanding of RIG-I signaling in viral infections and will inform future studies in the field.


Asunto(s)
Antivirales/metabolismo , Proteína 58 DEAD Box/metabolismo , Proteínas de Unión al ADN/metabolismo , Transducción de Señal , Factores de Transcripción/metabolismo , Proteínas de Motivos Tripartitos/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Células A549 , Animales , Línea Celular , Células Epiteliales/microbiología , Células Epiteliales/virología , Eliminación de Gen , Humanos , Ligandos , Ratones Endogámicos C57BL , ARN/metabolismo , Receptores Inmunológicos
10.
J Virol ; 90(15): 6936-6947, 2016 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27226365

RESUMEN

UNLABELLED: Novel influenza viruses often cause differential infection patterns across different age groups, an effect that is defined as heterogeneous demographic susceptibility. This occurred during the A/H2N2 pandemic, when children experienced higher influenza attack rates than adults. Since the recognition of conserved epitopes across influenza subtypes by CD8(+) cytotoxic T lymphocytes (CTLs) limit influenza disease, we hypothesized that conservation of CTL antigenic peptides (Ag-p) in viruses circulating before the pH2N2-1957 may have resulted in differential CTL immunity. We compared viruses isolated in the years preceding the pandemic (1941 to 1957) to which children and adults were exposed to viruses circulating decades earlier (1918 to 1940), which could infect adults only. Consistent with phylogenetic models, influenza viruses circulating from 1941 to 1957, which infected children, shared with pH2N2 the majority (∼89%) of the CTL peptides within the most immunogenic nucleoprotein, matrix 1, and polymerase basic 1, thus providing evidence for minimal pH2N2 CTL escape in children. Our study, however, identified potential CTL immune evasion from pH2N2 irrespective of age, within HLA-A*03:01(+) individuals for PB1471-L473V/N476I variants and HLA-B*15:01(+) population for NP404-414-V408I mutant. Further experiments using the murine model of B-cell-deficient mice showed that multiple influenza infections resulted in superior protection from influenza-induced morbidity, coinciding with accumulation of tissue-resident memory CD8(+) T cells in the lung. Our study suggests that protection against H2N2-1957 pandemic influenza was most likely linked to the number of influenza virus infections prior to the pandemic challenge rather than differential preexisting CTL immunity. Thus, the regimen of a CTL-based vaccine/vaccine-component may benefit from periodic boosting to achieve fully protective, asymptomatic influenza infection. IMPORTANCE: Due to a lack of cross-reactive neutralizing antibodies, children are particularly susceptible to influenza infections caused by novel viral strains. Preexisting T cell immunity directed at conserved viral regions, however, can provide protection against influenza viruses, promote rapid recovery and better clinical outcomes. When we asked whether high susceptibility of children (compared to adults) to the pandemic H2N2 influenza strain was associated with immune evasion from T-cell immunity, we found high conservation within T-cell antigenic regions in pandemic H2N2. However, the number of influenza infections prior to the challenge was linked to protective, asymptomatic infections and establishment of tissue-resident memory T cells. Our study supports development of vaccines that prime and boost T cells to elicit cross-strain protective T cells, especially tissue-resident memory T cells, for lifelong immunity against distinct influenza viruses.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Epítopos de Linfocito T/inmunología , Gripe Humana/inmunología , Infecciones por Orthomyxoviridae/inmunología , Orthomyxoviridae/inmunología , Pandemias , Linfocitos T Citotóxicos/inmunología , Adulto , Animales , Linfocitos B/inmunología , Niño , Protección Cruzada , Evolución Molecular , Femenino , Humanos , Gripe Humana/virología , Ratones , Infecciones por Orthomyxoviridae/virología , Filogenia
11.
J Gen Virol ; 97(12): 3205-3214, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27902386

RESUMEN

FluMist has been used in children and adults for more than 10 years. As pre-existing CD8+ T cell memory pools can provide heterologous immunity against distinct influenza viruses, it is important to understand influenza-specific CD8+ T cell responses elicited by different live attenuated influenza virus (LAIV) regimens. In this study, we immunized mice intranasally with two different doses of live-attenuated PR8 virus (PR8 ts, H1N1), low and high, and then assessed protective efficacy by challenging animals with heterosubtypic X31-H3N2 virus at 6 weeks post-vaccination. Different LAIV doses elicited influenza-specific CD8+ T cell responses in lungs and spleen, but unexpectedly not in bronchoalveolar lavage. Interestingly, the immunodominance hierarchy at the acute phase after immunization varied depending on the LAIV dose; however, these differences disappeared at 6 weeks post-vaccination, resulting in generation of comparable CD8+ T cell memory pools. After vaccination with either dose, sufficient numbers of specific CD8+ T cells were generated for recall and protection of mice against heterosubtypic H1N1→H3N2 challenge. As a result, immunized mice displayed reduced weight loss, diminished inflammatory responses and lower viral titres in lungs, when compared to unvaccinated animals. Interestingly, the higher dose led to enhanced viral clearance on day 5 post-challenge, though this was not associated with increased CD8+ T cell responses, but with higher levels of non-neutralizing antibodies against the priming virus. Our study suggests that, while different LAIV doses result in distinct immune profiles, even a low dose produces sufficient protective CD8+ T cell memory against challenge infection, though the high dose results in more rapid viral clearance and reduced inflammation.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Subtipo H1N1 del Virus de la Influenza A/inmunología , Subtipo H3N2 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/administración & dosificación , Gripe Humana/inmunología , Vacunas Atenuadas/administración & dosificación , Animales , Anticuerpos Antivirales/inmunología , Humanos , Memoria Inmunológica , Subtipo H1N1 del Virus de la Influenza A/genética , Subtipo H3N2 del Virus de la Influenza A/genética , Vacunas contra la Influenza/inmunología , Gripe Humana/prevención & control , Gripe Humana/virología , Pulmón/virología , Ratones , Ratones Endogámicos C57BL , Vacunas Atenuadas/inmunología
12.
PLoS Pathog ; 10(5): e1004134, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24809749

RESUMEN

Suppressor of cytokine signaling (SOCS) proteins are key regulators of innate and adaptive immunity. There is no described biological role for SOCS4, despite broad expression in the hematopoietic system. We demonstrate that mice lacking functional SOCS4 protein rapidly succumb to infection with a pathogenic H1N1 influenza virus (PR8) and are hypersusceptible to infection with the less virulent H3N2 (X31) strain. In SOCS4-deficient animals, this led to substantially greater weight loss, dysregulated pro-inflammatory cytokine and chemokine production in the lungs and delayed viral clearance. This was associated with impaired trafficking of influenza-specific CD8 T cells to the site of infection and linked to defects in T cell receptor activation. These results demonstrate that SOCS4 is a critical regulator of anti-viral immunity.


Asunto(s)
Inmunidad Adaptativa/genética , Citocinas/efectos adversos , Citocinas/metabolismo , Inflamación/prevención & control , Subtipo H1N1 del Virus de la Influenza A/inmunología , Infecciones por Orthomyxoviridae/inmunología , Proteínas Supresoras de la Señalización de Citocinas/fisiología , Animales , Linfocitos T CD8-positivos/inmunología , Citoprotección/genética , Inflamación/genética , Inflamación/metabolismo , Mediadores de Inflamación/efectos adversos , Mediadores de Inflamación/metabolismo , Subtipo H1N1 del Virus de la Influenza A/crecimiento & desarrollo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Ratones Transgénicos , Infecciones por Orthomyxoviridae/virología , Carga Viral/genética
13.
Immunol Cell Biol ; 93(10): 909-13, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26077508

RESUMEN

Suppressor of cytokine signaling (SOCS) proteins are key regulators of innate and adaptive immunity. Mice lacking functional SOCS4 are hypersusceptible to primary infection with influenza A virus (IAV), displaying dysregulated pro-inflammatory cytokine and chemokine production in the lungs, delayed viral clearance and impaired trafficking of influenza-specific CD8(+) T cells to the site of infection. Therefore, we postulated that SOCS4 is a critical regulator of anti-viral immunity. Unexpectedly, SOCS4 was not required for CD8(+) T-cell memory generation, nor was it required to efficiently recall those cells in response to secondary IAV infection. Wild-type or SOCS4-deficient mice primed and re-challenged with serologically different influenza strains, did not show differences in susceptibility to IAV and cleared the virus from the lungs at the same rate. We have not observed differences in trafficking or numbers of IAV-specific cells, numbers of resident memory T cells or in cytokine profiles in lungs of infected animals. Our data show that despite an impaired primary immune response in Socs4(R108X/R108X) mice, SOCS4 is dispensable for an efficient recall response to influenza virus infection.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Pulmón/fisiología , Infecciones por Orthomyxoviridae/inmunología , Orthomyxoviridae/inmunología , Proteínas Supresoras de la Señalización de Citocinas/metabolismo , Animales , Linfocitos T CD8-positivos/virología , Movimiento Celular/genética , Citocinas/metabolismo , Inmunidad/genética , Memoria Inmunológica/genética , Inmunofenotipificación , Pulmón/virología , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Proteínas Supresoras de la Señalización de Citocinas/genética
14.
J Biol Inorg Chem ; 20(7): 1193-203, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26411702

RESUMEN

Eight bismuth(III) complexes derived from the simple α-hydroxycarboxylic acids; gluconic (H6-glu), tartaric (H4-tar), mandelic (H2-man), malic (H3-mal) and glycolic (H2-gly) have been synthesised and characterised. The complexes are formed through direct treatment of the organic acids with Bi(NO3)3·5H2O ([Bi(H2-tar)(H3- tar)] 2, [Bi(mal)(NO3)(H2O)2] 6, [Bi(gly)(NO3)(H2O)] 8) or Bi(OtBu)3 ([Bi(H-tar)(H2O)2] 1, [Bi(man)(H-man) (H2O)] 4, [Bi2(H-mal)3] 5, [Bi(gly)(H-gly)] 7), or through metathesis of the sodium salts with Bi(NO3)3·5H2O ([Bi(H3-glu)]3). Reactions with both glucuronic and mucic acid proved to be unsuccessful. Small crystals of [Bi(gly)4(NO3)4(H2O)4]·5H2O 8 were obtained from aqueous solution and analysed by synchrotron X-ray diffraction. The data were relatively poor but composition and connectivity were established, confirming and supporting other analyses. Those complexes which displayed sufficient solubility; 2, 4, 7 and 8, were tested for their anti-Leishmanial activity against parasite promastigotes and amastigotes, and for toxicity against human fibroblast cells. All four complexes and their parent acids showed no toxicity towards either the promastigotes or fibroblast cells. However, the two glycolate complexes showed selective toxicity towards amastigotes with complex 8 providing for a low % viability of 1.8 ± 0.9 at 50.0 µM. Graphical Abstract Novel bismuth(III) complexes derived from α-hydroxycarboxylic acids have been synthesised, characterised and assessed for their anti-leishmanial activity. The glycolate complexes are selectively toxic against parasite amastigotes, with all complexes being nontoxic towards promastigotes and human fibroblast cells.


Asunto(s)
Bismuto/química , Ácidos Carboxílicos/farmacología , Glicolatos/química , Leishmania major/efectos de los fármacos , Antiparasitarios/química , Antiparasitarios/farmacología , Ácidos Carboxílicos/química , Complejos de Coordinación/química , Fibroblastos/efectos de los fármacos , Fibroblastos/parasitología , Glicolatos/farmacología , Humanos , Modelos Moleculares , Estructura Molecular
15.
Parasitology ; : 1-19, 2014 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-25075460

RESUMEN

SUMMARY Leishmania are protozoan parasites spread by a sandfly insect vector and causing a spectrum of diseases collectively known as leishmaniasis. The disease is a significant health problem in many parts of the world, resulting in an estimated 1·3 million new cases and 30 000 deaths annually. Current treatment is based on chemotherapy, which is difficult to administer, expensive and becoming ineffective in several endemic regions. To date there is no vaccine against leishmaniasis, although extensive evidence from studies in animal models indicates that solid protection can be achieved upon immunization. This review focuses on immune responses to Leishmania in both cutaneous and visceral forms of the disease, pointing to the complexity of the immune response and to a range of evasive mechanisms utilized by the parasite to bypass those responses. The amalgam of innate and acquired immunity combined with the paucity of data on the human immune response is one of the major problems currently hampering vaccine development and implementation.

16.
Nat Commun ; 15(1): 2619, 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38521764

RESUMEN

Immunity to infectious diseases is predominantly studied by measuring immune responses towards a single pathogen, although co-infections are common. In-depth mechanisms on how co-infections impact anti-viral immunity are lacking, but are highly relevant to treatment and prevention. We established a mouse model of co-infection with unrelated viruses, influenza A (IAV) and Semliki Forest virus (SFV), causing disease in different organ systems. SFV infection eight days before IAV infection results in prolonged IAV replication, elevated cytokine/chemokine levels and exacerbated lung pathology. This is associated with impaired lung IAV-specific CD8+ T cell responses, stemming from suboptimal CD8+ T cell activation and proliferation in draining lymph nodes, and dendritic cell paralysis. Prior SFV infection leads to increased blood brain barrier permeability and presence of IAV RNA in brain, associated with increased trafficking of IAV-specific CD8+ T cells and establishment of long-term tissue-resident memory. Relative to lung IAV-specific CD8+ T cells, brain memory IAV-specific CD8+ T cells have increased TCR repertoire diversity within immunodominant DbNP366+CD8+ and DbPA224+CD8+ responses, featuring suboptimal TCR clonotypes. Overall, our study demonstrates that infection with an unrelated neurotropic virus perturbs IAV-specific immune responses and exacerbates IAV disease. Our work provides key insights into therapy and vaccine regimens directed against unrelated pathogens.


Asunto(s)
Coinfección , Vacunas contra la Influenza , Gripe Humana , Infecciones por Orthomyxoviridae , Virus , Ratones , Animales , Humanos , Gripe Humana/patología , Linfocitos T CD8-positivos , Coinfección/patología , Receptores de Antígenos de Linfocitos T , Pulmón/patología
17.
Proc Natl Acad Sci U S A ; 107(28): 12599-604, 2010 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-20616031

RESUMEN

Preexisting T-cell immunity directed at conserved viral regions promotes enhanced recovery from influenza virus infections, with there being some evidence of cross-protection directed at variable peptides. Strikingly, many of the immunogenic peptides derived from the current pandemic A(H1N1)-2009 influenza virus are representative of the catastrophic 1918 "Spanish flu" rather than more recent "seasonal" strains. We present immunological and structural analyses of cross-reactive CD8(+) T-cell-mediated immunity directed at a variable (although highly cross-reactive) immunodominant NP(418-426) peptide that binds to a large B7 family (HLA-B*3501/03/0702) found throughout human populations. Memory CD8(+) T-cell specificity was probed for 12 different NP(418) mutants that emerged over the 9 decades between the 1918 and 2009 pandemics. Although there is evidence of substantial cross-reactivity among seasonal NP(418) mutants, current memory T-cell profiles show no preexisting immunity to the 2009-NP(418) variant or the 1918-NP(418) variant. Natural infection with the A(H1N1)-2009 virus, however, elicits CD8(+) T cells specific for the 2009-NP(418) and 1918-NP(418) epitopes. This analysis points to the potential importance of cross-reactive T-cell populations that cover the possible spectrum of T-cell variants and suggests that the identification of key residues/motifs that elicit cross-reactive T-cell sets could facilitate the evolution of immunization protocols that provide a measure of protection against unpredicted pandemic influenza viruses. Thus, it is worth exploring the potential of vaccines that incorporate peptide variants with a proven potential for broader immunogenicity, especially to those that are not recognized by the current memory T-cell pool generated by exposure to influenza variants that cause successive seasonal epidemics.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/inmunología , Virus de la Influenza A/inmunología , Gripe Humana/inmunología , Linfocitos T/inmunología , Linfocitos T CD8-positivos/inmunología , Protección Cruzada , Reacciones Cruzadas/inmunología , Brotes de Enfermedades , Epítopos/inmunología , Antígenos HLA-B/inmunología , Humanos , Inmunidad Celular/inmunología , Vacunas contra la Influenza/inmunología , Recuento de Linfocitos , Especificidad del Receptor de Antígeno de Linfocitos T/inmunología , Virus/inmunología
18.
EJHaem ; 4(1): 216-220, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36819189

RESUMEN

Zanubrutinib-treated and treatment-naïve patients with chronic lymphocytic leukaemia (CLL) or Waldenstrom's macroglobulinaemia were recruited in this prospective study to comprehensively profile humoral and cellular immune responses to COVID-19 vaccination. Overall, 45 patients (median 72 years old) were recruited; the majority were male (71%), had CLL (76%) and were on zanubrutinib (78%). Seroconversion rates were 65% and 77% following two and three doses, respectively. CD4+ and CD8+ T-cell response rates increased with third dose. In zanubrutinib-treated patients, 86% developed either a humoral or cellular response. Patients on zanubrutinib developed substantial immune responses following two COVID-19 vaccine doses, which further improved following a third dose.

19.
Open Forum Infect Dis ; 10(11): ofad550, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38023562

RESUMEN

Background: In-depth immunogenicity studies of tixagevimab-cilgavimab (T-C) are lacking, including following breakthrough coronavirus disease 2019 (COVID-19) in vaccinated patients with hematologic malignancy (HM) receiving T-C as pre-exposure prophylaxis. Methods: We performed a prospective, observational cohort study and detailed immunological analyses of 93 patients with HM who received T-C from May 2022, with and without breakthrough infection, during a follow-up period of 6 months and dominant Omicron BA.5 variant. Results: In 93 patients who received T-C, there was an increase in Omicron BA.4/5 receptor-binding domain (RBD) immunoglobulin G (IgG) antibody titers that persisted for 6 months and was equivalent to 3-dose-vaccinated uninfected healthy controls at 1 month postinjection. Omicron BA.4/5 neutralizing antibody was lower in patients receiving B-cell-depleting therapy within 12 months despite receipt of T-C. COVID-19 vaccination during T-C treatment did not incrementally improve RBD or neutralizing antibody levels. In 16 patients with predominantly mild breakthrough infection, no change in serum neutralization of Omicron BA.4/5 postinfection was detected. Activation-induced marker assay revealed an increase in CD4+ (but not CD8+) T cells post infection, comparable to previously infected healthy controls. Conclusions: Our study provides proof-of-principle for a pre-exposure prophylaxis strategy and highlights the importance of humoral and cellular immunity post-breakthrough COVID-19 in vaccinated patients with HM.

20.
JCI Insight ; 8(7)2023 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-37036008

RESUMEN

Pregnancy poses a greater risk for severe COVID-19; however, underlying immunological changes associated with SARS-CoV-2 during pregnancy are poorly understood. We defined immune responses to SARS-CoV-2 in unvaccinated pregnant and nonpregnant women with acute and convalescent COVID-19, quantifying 217 immunological parameters. Humoral responses to SARS-CoV-2 were similar in pregnant and nonpregnant women, although our systems serology approach revealed distinct antibody and FcγR profiles between pregnant and nonpregnant women. Cellular analyses demonstrated marked differences in NK cell and unconventional T cell activation dynamics in pregnant women. Healthy pregnant women displayed preactivated NK cells and γδ T cells when compared with healthy nonpregnant women, which remained unchanged during acute and convalescent COVID-19. Conversely, nonpregnant women had prototypical activation of NK and γδ T cells. Activation of CD4+ and CD8+ T cells and T follicular helper cells was similar in SARS-CoV-2-infected pregnant and nonpregnant women, while antibody-secreting B cells were increased in pregnant women during acute COVID-19. Elevated levels of IL-8, IL-10, and IL-18 were found in pregnant women in their healthy state, and these cytokine levels remained elevated during acute and convalescent COVID-19. Collectively, we demonstrate perturbations in NK cell and γδ T cell activation in unvaccinated pregnant women with COVID-19, which may impact disease progression and severity during pregnancy.


Asunto(s)
COVID-19 , Embarazo , Femenino , Humanos , SARS-CoV-2 , Células Asesinas Naturales , Linfocitos T CD8-positivos , Anticuerpos
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