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1.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33688034

RESUMO

The current pandemic of COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) highlights an urgent need to develop a safe, efficacious, and durable vaccine. Using a measles virus (rMeV) vaccine strain as the backbone, we developed a series of recombinant attenuated vaccine candidates expressing various forms of the SARS-CoV-2 spike (S) protein and its receptor binding domain (RBD) and evaluated their efficacy in cotton rat, IFNAR-/-mice, IFNAR-/--hCD46 mice, and golden Syrian hamsters. We found that rMeV expressing stabilized prefusion S protein (rMeV-preS) was more potent in inducing SARS-CoV-2-specific neutralizing antibodies than rMeV expressing full-length S protein (rMeV-S), while the rMeVs expressing different lengths of RBD (rMeV-RBD) were the least potent. Animals immunized with rMeV-preS produced higher levels of neutralizing antibody than found in convalescent sera from COVID-19 patients and a strong Th1-biased T cell response. The rMeV-preS also provided complete protection of hamsters from challenge with SARS-CoV-2, preventing replication in lungs and nasal turbinates, body weight loss, cytokine storm, and lung pathology. These data demonstrate that rMeV-preS is a safe and highly efficacious vaccine candidate, supporting its further development as a SARS-CoV-2 vaccine.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Vetores Genéticos , Vírus do Sarampo , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Sintéticas/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/complicações , COVID-19/patologia , Vacinas contra COVID-19/genética , Cricetinae , Modelos Animais de Doenças , Expressão Gênica , Vetores Genéticos/genética , Vetores Genéticos/imunologia , Humanos , Imunização , Imunogenicidade da Vacina , Vírus do Sarampo/genética , Vírus do Sarampo/imunologia , Camundongos , Camundongos Transgênicos , Ratos , Glicoproteína da Espícula de Coronavírus/genética , Vacinas Sintéticas/genética
2.
Am J Transplant ; 22(10): 2306-2322, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35671112

RESUMO

Human cytomegalovirus (HCMV) infection is associated with renal allograft failure. Allograft damage in animal models is accelerated by CMV-induced T helper 17 (Th17) cell infiltrates. However, the mechanisms whereby CMV promotes Th17 cell-mediated pathological organ inflammation are uncharacterized. Here we demonstrate that murine CMV (MCMV)-induced intragraft Th17 cells have a Th1/17 phenotype co-expressing IFN-γ and/or TNF-α, but only a minority of these cells are MCMV specific. Instead, MCMV promotes intragraft expression of CCL20 and CXCL10, which are associated with recruitment of CCR6+ CXCR3+ Th17 cells. MCMV also enhances Th17 cell infiltrates after ischemia-reperfusion injury, independent of allogeneic responses. Pharmacologic inhibition of the Th17 cell signature cytokine, IL-17A, ameliorates MCMV-associated allograft damage without increasing intragraft viral loads or reducing MCMV-specific Th1 cell infiltrates. Clinically, HCMV DNAemia is associated with higher serum IL-17A among renal transplant patients with acute rejection, linking HCMV reactivation with Th17 cell cytokine expression. In summary, CMV promotes allograft damage via cytokine-mediated Th1/17 cell recruitment, which may be pharmacologically targeted to mitigate graft injury while preserving antiviral T cell immunity.


Assuntos
Infecções por Citomegalovirus , Transplante de Rim , Muromegalovirus , Nefrite , Insuficiência Renal , Aloenxertos/metabolismo , Animais , Antivirais , Citocinas/metabolismo , Humanos , Inflamação/patologia , Interleucina-17/metabolismo , Transplante de Rim/efeitos adversos , Camundongos , Insuficiência Renal/complicações , Células Th1 , Células Th17 , Fator de Necrose Tumoral alfa/metabolismo
3.
J Allergy Clin Immunol ; 147(2): 532-544.e1, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33007327

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel coronavirus that emerged recently and has created a global pandemic. Symptomatic SARS-CoV-2 infection, termed coronavirus disease 2019 (COVID-19), has been associated with a host of symptoms affecting numerous organ systems, including the lungs, cardiovascular system, kidney, central nervous system, gastrointestinal tract, and skin, among others. OBJECTIVE: Although several risk factors have been identified as related to complications from and severity of COVID-19, much about the virus remains unknown. The host immune response appears to affect the outcome of disease. It is not surprising that patients with intrinsic or secondary immune compromise might be particularly susceptible to complications from SARS-CoV-2 infection. Pathogenic loss-of-function or gain-of-function heterozygous variants in nuclear factor-κB2 have been reported to be associated with either a combined immunodeficiency or common variable immunodeficiency phenotype. METHODS: We evaluated the functional consequence and immunologic phenotype of a novel NFKB2 loss of function variant in a 17-year-old male patient and describe the clinical management of SARS-CoV-2 infection in this context. RESULTS: This patient required a 2-week hospitalization for SARS-CoV-2 infection, including 7 days of mechanical ventilation. We used biologic therapies to avert potentially fatal acute respiratory distress syndrome and treat hyperinflammatory responses. The patient had an immunologic phenotype of B-cell dysregulation with decreased switched memory B cells. Despite the underlying immune dysfunction, he recovered from the infection with intense management. CONCLUSIONS: This clinical case exemplifies some of the practical challenges in management of patients with SARS-CoV-2 infection, especially in the context of underlying immune dysregulation.


Assuntos
COVID-19/genética , Subunidade p52 de NF-kappa B/genética , SARS-CoV-2 , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/uso terapêutico , Adolescente , Alanina/análogos & derivados , Alanina/uso terapêutico , Anticorpos Antivirais/sangue , Antivirais/uso terapêutico , Linfócitos B/imunologia , COVID-19/diagnóstico , COVID-19/imunologia , COVID-19/terapia , Hospitalização , Humanos , Interleucina-6/sangue , Masculino , Respiração Artificial , SARS-CoV-2/imunologia , Índice de Gravidade de Doença
4.
J Pediatr ; 214: 34-40, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31493911

RESUMO

OBJECTIVE: To determine the frequency of detection of cytomegalovirus (CMV) in surgical or autopsy intestinal tissue from infants with necrotizing enterocolitis (NEC) or spontaneous intestinal perforation (SIP) of the small bowel. STUDY DESIGN: This was a retrospective cohort study of infants in the neonatal intensive care unit at Nationwide Children's Hospital, Columbus, Ohio, with NEC (Bell stage ≥2B) or SIP from 2000 to 2016. Paraffin-embedded surgical or autopsy intestinal tissues were examined for CMV by polymerase chain reaction (PCR) and immunohistochemistry (IHC), and clinical characteristics of CMV-positive vs CMV-negative cases were compared. RESULTS: CMV was detected by PCR or IHC in 7 (4%) of 178 infants with surgical or autopsy- confirmed NEC (n = 6) or SIP (n = 1). Among 143 NEC cases (123 surgical, 20 autopsy), CMV was detected in 6 (4%): 4 (2 surgical, 2 autopsy) by both PCR and IHC, and 2 (surgical) by PCR only. Among 35 SIP cases (32 surgical, 3 autopsy), 1 (3%) surgical case was positive, by PCR only. CMV-associated NEC cases had lower median gestational age (24 vs 28 weeks; P = .02), birth weight (649 vs 1121 g; P = .04), and platelet count (16 000/mm3 vs 50 000/mm3; P = .018) compared with CMV-negative cases, respectively. No association was found with receipt of maternal milk, age at NEC diagnosis, male sex, cholestasis, or mortality. CONCLUSIONS: CMV was detected in intestinal tissue from 4% of NEC or SIP cases (NEC, 4%; SIP, 3%). Lower gestational age, lower birth weight, and thrombocytopenia were significantly associated with detection of CMV in NEC or SIP cases.


Assuntos
Infecções por Citomegalovirus/complicações , Citomegalovirus/isolamento & purificação , Enterocolite Necrosante/virologia , Perfuração Intestinal/virologia , Intestino Delgado/virologia , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos
5.
Pediatr Transplant ; 23(3): e13382, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30786115

RESUMO

BACKGROUND: CMV is associated with adverse effects in renal transplant recipients. The objective of this study was to characterize the incidence and timing of CMV and EBV infections in relation to valGCV prophylaxis in a pediatric renal transplant cohort. METHODS: Retrospective cohort of pediatric renal transplant patients given universal valGCV prophylaxis and universal viral surveillance was evaluated. Demographics, prophylaxis, acute rejection, and CMV and EBV infections were abstracted. RESULTS: A total of 92 pediatric renal allograft recipients, 2008-2013, were included. One or more viral infections developed in 77/92 (83.7%) of the patients. EBV was the most common in 62/92 (67%) patients, irrespective of valGCV (82% of episodes occurring on valGCV). CMV DNAemia occurred in 30/92 (33%) patients, 14 episodes (47%) occurring on valGCV. Incidence of breakthrough CMV on prophylaxis was 15% and was associated with persistent DNAemia (OR 7.8, CI:1.6-32.9, P < 0.02). CMV tissue-invasive disease was not seen. CMV syndrome occurred in 10% of the cohort, only in CMV D+ patients, and only one symptomatic breakthrough infection required treatment. Out of 92, 21 (23%) had simultaneous co-infections with 2-3 viruses. CONCLUSIONS: Viral infections in pediatric renal transplant recipients receiving universal valGCV prophylaxis were common. EBV infections were not reduced by valGCV prophylaxis, and nearly half of CMV infections occurred on valGCV. Symptomatic CMV infection while on prophylaxis was rare. valGCV prophylaxis may prevent symptomatic CMV infection but not EBV infection, and frequent CMV surveillance in pediatric renal transplant recipients on prophylaxis may not be necessary.


Assuntos
Infecções por Citomegalovirus/etiologia , Infecções por Vírus Epstein-Barr/etiologia , Transplante de Rim/métodos , Valganciclovir/uso terapêutico , Adolescente , Antivirais/uso terapêutico , Criança , Pré-Escolar , Citomegalovirus , Infecções por Citomegalovirus/complicações , Infecções por Vírus Epstein-Barr/complicações , Feminino , Ganciclovir/uso terapêutico , Rejeição de Enxerto , Herpesvirus Humano 4 , Humanos , Imunossupressores/uso terapêutico , Incidência , Masculino , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Transplantados
6.
Am J Transplant ; 18(11): 2647-2662, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29659179

RESUMO

Human cytomegalovirus (HCMV) donor positive (D+) serostatus with acute rejection is associated with renal allograft loss, but the impact of recipient positive (R+) serostatus is unclear. In an allogeneic renal transplant model, antiviral natural killer (NK) and CD8+ T cell memory responses in murine CMV (MCMV) D+/R+ transplants were compared to D-/R- and D+/R- transplants, with recipient infection varied by MCMV dose and strain. D+/R- transplants had high primary antiviral cytolytic (interferon-γ+) and cytotoxic (granzyme B+) NK responses, whereas NK memory responses were lower in D+/R+ recipients receiving a high primary MCMV dose. Despite MCMV immunity, D+/R+ recipients receiving a low MCMV dose showed primary-like high cytolytic and cytotoxic NK responses. D+/R+ transplants infected with different D/R strains had low cytolytic NK responses but high cytotoxic NK responses. NK memory also induced a novel TNF-α+ NK response among high-dose virus recipients. MCMV+ transplants had greater Th17 responses than MCMV-uninfected transplants and Th17 inhibition ameliorated graft injury. All MCMV+ recipients had similar CD8+ T cell responses. In sum, NK and Th17 responses, but not CD8+ T cells, varied according to conditions of primary recipient infection. This variability could contribute to variable graft outcomes in HCMV D+/R+ renal transplantation.


Assuntos
Infecções por Citomegalovirus/imunologia , Rejeição de Enxerto/etiologia , Transplante de Rim/efeitos adversos , Células Matadoras Naturais/imunologia , Muromegalovirus/classificação , Células Th17/imunologia , Carga Viral/imunologia , Aloenxertos , Animais , Infecções por Citomegalovirus/virologia , Rejeição de Enxerto/patologia , Células Matadoras Naturais/patologia , Células Matadoras Naturais/virologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Muromegalovirus/imunologia , Células Th17/patologia , Células Th17/virologia
7.
J Pediatr ; 200: 196-201.e1, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29784513

RESUMO

OBJECTIVE: To evaluate the impact of race and ethnicity upon the prevalence and clinical spectrum of congenital cytomegalovirus infection (cCMV). STUDY DESIGN: From 2007 to 2012, 100 332 infants from 7 medical centers were screened for cCMV while in the hospital. Ethnicity and race were collected and cCMV prevalence rates were calculated. RESULTS: The overall prevalence of cCMV in the cohort was 4.5 per 1000 live births (95% CI, 4.1-4.9). Black infants had the highest cCMV prevalence (9.5 per 1000 live births; 95% CI, 8.3-11.0), followed by multiracial infants (7.8 per 1000 live births; 95% CI, 4.7-12.0). Significantly lower prevalence rates were observed in non-Hispanic white infants (2.7 per 1000 live births; 95% CI, 2.2-3.3), Hispanic white infants (3.0 per 1000 live births; 95% CI, 2.4-3.6), and Asian infants (1.0 per 1000 live births; 95% CI, 0.3-2.5). After adjusting for socioeconomic status and maternal age, black infants were significantly more likely to have cCMV compared with non-Hispanic white infants (adjusted prevalence OR, 1.9; 95% CI, 1.4-2.5). Hispanic white infants had a slightly lower risk of having cCMV compared with non-Hispanic white infants (adjusted prevalence OR, 0.7; 95% CI, 0.5-1.0). However, no significant differences in symptomatic cCMV (9.6%) and sensorineural hearing loss (7.8%) were observed between the race/ethnic groups. CONCLUSIONS: Significant racial and ethnic differences exist in the prevalence of cCMV, even after adjusting for socioeconomic status and maternal age. Although once infected, the newborn disease and rates of hearing loss in infants are similar with respect to race and ethnicity.


Assuntos
Infecções por Citomegalovirus/etnologia , Etnicidade , Programas de Rastreamento/métodos , Grupos Raciais , Adulto , Infecções por Citomegalovirus/congênito , Feminino , Seguimentos , Humanos , Recém-Nascido , Masculino , Prevalência , Estudos Retrospectivos , Estados Unidos/epidemiologia
8.
Antimicrob Agents Chemother ; 60(9): 5130-4, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27551008

RESUMO

Stenotrophomonas maltophilia is an emerging multidrug-resistant (MDR) opportunistic pathogen for which new antibiotic options are urgently needed. We report our clinical experience treating a 19-year-old renal transplant recipient who developed prolonged bacteremia due to metallo-ß-lactamase-producing S. maltophilia refractory to conventional treatment. The infection recurred despite a prolonged course of colistimethate sodium (colistin) but resolved with the use of a novel drug combination with clinical efficacy against the patient's S. maltophilia isolate.


Assuntos
Compostos Azabicíclicos/uso terapêutico , Aztreonam/uso terapêutico , Bacteriemia/tratamento farmacológico , Ceftazidima/uso terapêutico , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Transplante de Rim , Stenotrophomonas maltophilia/efeitos dos fármacos , Antibacterianos/uso terapêutico , Bacteriemia/microbiologia , Bacteriemia/patologia , Colistina/uso terapêutico , Combinação de Medicamentos , Farmacorresistência Bacteriana Múltipla , Substituição de Medicamentos , Expressão Gênica , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/patologia , Humanos , Masculino , Doenças Renais Policísticas/patologia , Doenças Renais Policísticas/cirurgia , Stenotrophomonas maltophilia/genética , Stenotrophomonas maltophilia/crescimento & desenvolvimento , Stenotrophomonas maltophilia/patogenicidade , Adulto Jovem , beta-Lactamases/genética , beta-Lactamases/metabolismo
9.
J Immunol ; 193(11): 5604-12, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25355920

RESUMO

Circulating monocytes carrying human CMV (HCMV) migrate into tissues, where they differentiate into HCMV-infected resident macrophages that upon interaction with bacterial products may potentiate tissue inflammation. In this study, we investigated the mechanism by which HCMV promotes macrophage-orchestrated inflammation using a clinical isolate of HCMV (TR) and macrophages derived from primary human monocytes. HCMV infection of the macrophages, which was associated with viral DNA replication, significantly enhanced TNF-α, IL-6, and IL-8 gene expression and protein production in response to TLR4 ligand (LPS) stimulation compared with mock-infected LPS-stimulated macrophages during a 6-d in vitro infection. HCMV infection also potentiated TLR5 ligand-stimulated cytokine production. To elucidate the mechanism by which HCMV infection potentiated inducible macrophage responses, we show that infection by HCMV promoted the maintenance of surface CD14 and TLR4 and TLR5, which declined over time in mock-infected macrophages, and enhanced both the intracellular expression of adaptor protein MyD88 and the inducible phosphorylation of IκBα and NF-κB. These findings provide additional information toward elucidating the mechanism by which HCMV potentiates bacteria-induced NF-κB-mediated macrophage inflammatory responses, thereby enhancing organ inflammation in HCMV-infected tissues.


Assuntos
Infecções por Citomegalovirus/imunologia , Citomegalovirus/fisiologia , Macrófagos/imunologia , Células Cultivadas , Citocinas/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/imunologia , Macrófagos/virologia , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/imunologia , Receptor 5 Toll-Like/imunologia , Replicação Viral
10.
N Engl J Med ; 364(22): 2111-8, 2011 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-21631323

RESUMO

BACKGROUND: Congenital cytomegalovirus (CMV) infection is an important cause of hearing loss, and most infants at risk for CMV-associated hearing loss are not identified early in life because of failure to test for the infection. The standard assay for newborn CMV screening is rapid culture performed on saliva specimens obtained at birth, but this assay cannot be automated. Two alternatives--real-time polymerase-chain-reaction (PCR)-based testing of a liquid-saliva or dried-saliva specimen obtained at birth--have been developed. METHODS: In our prospective, multicenter screening study of newborns, we compared real-time PCR assays of liquid-saliva and dried-saliva specimens with rapid culture of saliva specimens obtained at birth. RESULTS: A total of 177 of 34,989 infants (0.5%; 95% confidence interval [CI], 0.4 to 0.6) were positive for CMV, according to at least one of the three methods. Of 17,662 newborns screened with the use of the liquid-saliva PCR assay, 17,569 were negative for CMV, and the remaining 85 infants (0.5%; 95% CI, 0.4 to 0.6) had positive results on both culture and PCR assay. The sensitivity and specificity of the liquid-saliva PCR assay were 100% (95% CI, 95.8 to 100) and 99.9% (95% CI, 99.9 to 100), respectively, and the positive and negative predictive values were 91.4% (95% CI, 83.8 to 96.2) and 100% (95% CI, 99.9 to 100), respectively. Of 17,327 newborns screened by means of the dried-saliva PCR assay, 74 were positive for CMV, whereas 76 (0.4%; 95% CI, 0.3 to 0.5) were found to be CMV-positive on rapid culture. Sensitivity and specificity of the dried-saliva PCR assay were 97.4% (95% CI, 90.8 to 99.7) and 99.9% (95% CI, 99.9 to 100), respectively. The positive and negative predictive values were 90.2% (95% CI, 81.7 to 95.7) and 99.9% (95% CI, 99.9 to 100), respectively. CONCLUSIONS: Real-time PCR assays of both liquid- and dried-saliva specimens showed high sensitivity and specificity for detecting CMV infection and should be considered potential screening tools for CMV in newborns. (Funded by the National Institute on Deafness and Other Communication Disorders.).


Assuntos
Infecções por Citomegalovirus/diagnóstico , Citomegalovirus/isolamento & purificação , Triagem Neonatal/métodos , Reação em Cadeia da Polimerase/métodos , Saliva/virologia , Técnicas Bacteriológicas , Citomegalovirus/genética , Infecções por Citomegalovirus/virologia , DNA Viral/análise , Feminino , Humanos , Recém-Nascido , Masculino , Estudos Prospectivos
11.
J Perinatol ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849546

RESUMO

OBJECTIVE: The objective of this study was to determine the frequency of common gastrointestinal bacterial, parasitic, and viral pathogen detection in necrotizing enterocolitis (NEC) or spontaneous intestinal perforation (SIP) -associated intestinal tissue. STUDY DESIGN: Retrospective cohort study examined formalin fixed, paraffin embedded (FFPE) surgical or autopsy intestinal tissue from NEC or SIP specimens. DNA and RNA were extracted and analyzed by multiplex PCR panel (GIFA Biofire). DNA or RNA from stool samples containing each pathogen were extracted for positive controls. RESULTS: The total number of intestinal tissue samples were 193 from 310 infants (156 NEC, 37 SIP). Six (3%) infants with stage III NEC tested positive for a target pathogen; 2, C. difficile; 3, Enteroaggregtive E. coli; and 1, Giardia. No gastrointestinal viral pathogens were detected. CONCLUSION: Molecular testing yielded few GI pathogens suggesting that these organisms are likely not major causes or facilitators of NEC or SIP.

12.
J Virol ; 86(1): 610-4, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22072777

RESUMO

The chimeric herpes simplex viruses (HSV) are Δγ134.5 vectors encoding the human cytomegalovirus (HCMV) IRS1 or TRS1 genes. They are capable of late viral protein synthesis and are superior to Δγ134.5 HSVs in oncolytic activity. The interferon (IFN) response limits efficient HSV gene expression and replication. HCMV TRS1 and IRS1 restore one γ134.5 gene function: evasion of IFN-inducible protein kinase R, allowing late viral protein synthesis. Here we show that, unlike wild-type HSV, the chimeric HSV do not restore another γ134.5 function, the suppression of early IFN signaling mediated by IFN regulatory factor 3 (IRF3).


Assuntos
Citomegalovirus/genética , Herpes Simples/genética , Fator Regulador 3 de Interferon/imunologia , Terapia Viral Oncolítica/instrumentação , Simplexvirus/fisiologia , Proteínas Virais/genética , Linhagem Celular , Expressão Gênica , Vetores Genéticos/genética , Vetores Genéticos/imunologia , Vetores Genéticos/fisiologia , Herpes Simples/imunologia , Herpes Simples/metabolismo , Herpes Simples/virologia , Humanos , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/metabolismo , Interferon beta/genética , Interferon beta/imunologia , Fosforilação , Simplexvirus/genética , Simplexvirus/imunologia , Proteínas Virais/imunologia , Proteínas Virais/metabolismo , Replicação Viral
13.
Gastroenterology ; 140(1): 242-53, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20875417

RESUMO

BACKGROUND & AIMS: Premature neonates are predisposed to necrotizing enterocolitis (NEC), an idiopathic, inflammatory bowel necrosis. We investigated whether NEC occurs in the preterm intestine due to incomplete noninflammatory differentiation of intestinal macrophages, which increases the risk of a severe mucosal inflammatory response to bacterial products. METHODS: We compared inflammatory properties of human/murine fetal, neonatal, and adult intestinal macrophages. To investigate gut-specific macrophage differentiation, we next treated monocyte-derived macrophages with conditioned media from explanted human fetal and adult intestinal tissues. Transforming growth factor-ß (TGF-ß) expression and bioactivity were measured in fetal/adult intestine and in NEC. Finally, we used wild-type and transgenic mice to investigate the effects of deficient TGF-ß signaling on NEC-like inflammatory mucosal injury. RESULTS: Intestinal macrophages in the human preterm intestine (fetus/premature neonate), but not in full-term neonates and adults, expressed inflammatory cytokines. Macrophage cytokine production was suppressed in the developing intestine by TGF-ß, particularly the TGF-ß(2) isoform. NEC was associated with decreased tissue expression of TGF-ß(2) and decreased TGF-ß bioactivity. In mice, disruption of TGF-ß signaling worsened NEC-like inflammatory mucosal injury, whereas enteral supplementation with recombinant TGF-ß(2) was protective. CONCLUSIONS: Intestinal macrophages progressively acquire a noninflammatory profile during gestational development. TGF-ß, particularly the TGF-ß(2) isoform, suppresses macrophage inflammatory responses in the developing intestine and protects against inflammatory mucosal injury. Enterally administered TGF-ß(2) protected mice from experimental NEC-like injury.


Assuntos
Citocinas/metabolismo , Enterocolite Necrosante/imunologia , Intestinos/crescimento & desenvolvimento , Macrófagos/metabolismo , Fator de Crescimento Transformador beta2/metabolismo , Adulto , Animais , Células Cultivadas , Quimiotaxia de Leucócito , Humanos , Recém-Nascido , Intestinos/imunologia , Lipopolissacarídeos/metabolismo , Ativação de Macrófagos , Camundongos , Camundongos Transgênicos , NF-kappa B/metabolismo , Neutrófilos/metabolismo , Fator de Crescimento Transformador beta2/farmacologia
14.
PLoS Pathog ; 6(11): e1001170, 2010 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-21079788

RESUMO

Human cytomegalovirus (HCMV) infection is associated epidemiologically with poor outcome of renal allografts due to mechanisms which remain largely undefined. Transforming growth factor-ß1 (TGF-ß1), a potent fibrogenic cytokine, is more abundant in rejecting renal allografts that are infected with either HCMV or rat CMV as compared to uninfected, rejecting grafts. TGF-ß1 induces renal fibrosis via epithelial-to-mesenchymal transition (EMT) of renal epithelial cells, a process by which epithelial cells acquire mesenchymal characteristics and a migratory phenotype, and secrete molecules associated with extracellular matrix deposition and remodeling. We report that human renal tubular epithelial cells infected in vitro with HCMV and exposed to TGF-ß1 underwent morphologic and transcriptional changes of EMT, similar to uninfected cells. HCMV infected cells after EMT also activated extracellular latent TGF-ß1 via induction of MMP-2. Renal epithelial cells transiently transfected with only the HCMV IE1 or IE2 open reading frames and stimulated to undergo EMT also induced TGF-ß1 activation associated with MMP-2 production, suggesting a role for these viral gene products in MMP-2 production. Consistent with the function of these immediate early gene products, the antiviral agents ganciclovir and foscarnet did not inhibit TGF-ß1 production after EMT by HCMV infected cells. These results indicate that HCMV infected renal tubular epithelial cells can undergo EMT after exposure to TGF-ß1, similar to uninfected renal epithelial cells, but that HCMV infection by inducing active TGF-ß1 may potentiate renal fibrosis. Our findings provide in vitro evidence for a pathogenic mechanism that could explain the clinical association between HCMV infection, TGF-ß1, and adverse renal allograft outcome.


Assuntos
Infecções por Citomegalovirus/metabolismo , Citomegalovirus/patogenicidade , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/virologia , Fator de Crescimento Transformador beta1/metabolismo , Animais , Western Blotting , Diferenciação Celular , Células Cultivadas , Infecções por Citomegalovirus/patologia , Infecções por Citomegalovirus/virologia , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Transição Epitelial-Mesenquimal , Imunofluorescência , Humanos , Imunoprecipitação , Túbulos Renais Proximais/citologia , RNA Mensageiro/genética , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais
15.
Pediatr Transplant ; 16(6): 627-37, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22694244

RESUMO

qPCR and pp65 antigenemia assays are used to monitor CMV infection in renal transplant recipients, but correlation of assays in a pediatric population has not been evaluated. Paired CMV real-time qPCR and pp65 antigenemia tests from 882 blood samples collected from 115 pediatric renal transplant recipients were analyzed in this retrospective cohort study for the strength of association and clinical correlates. The assays correlated well in detecting infection (κ = 0.61). Higher qPCR values were demonstrated with increasing levels of antigenemia (p < 0.01). Discordant test results were associated with antiviral treatment (OR 4.33, p < 0.01) and low-level viremia, with odds of concordance increasing at higher qPCR values (OR 3.67, p < 0.01), and no discordance occurring above 8500 genomic equivalents/mL. Among discordant samples, neither test preceded the other in detecting initial infection or in returning to negative while on treatment. Only two cases of disease occurred during the two-yr study period. With strong agreement in the detection of CMV infection, either qPCR or pp65 antigenemia assays can be used effectively for monitoring pediatric renal transplant patients for both detection and resolution of infection.


Assuntos
Infecções por Citomegalovirus/diagnóstico , Citomegalovirus/genética , Transplante de Rim/métodos , Fosfoproteínas/imunologia , Reação em Cadeia da Polimerase/métodos , Insuficiência Renal/terapia , Proteínas da Matriz Viral/imunologia , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/virologia , Feminino , Seguimentos , Humanos , Lactente , Transplante de Rim/efeitos adversos , Masculino , Pediatria/métodos , Insuficiência Renal/complicações , Estudos Retrospectivos
16.
Front Pediatr ; 10: 846254, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35813379

RESUMO

Congenital CMV (cCMV) infection can affect infants born to mothers with preconceptional seroimmunity. To prevent cCMV due to nonprimary maternal infection, vaccines eliciting responses exceeding natural immunity may be required. Anti-gM/gN antibodies have neutralizing capacity in-vitro and in animal models, but anti-gM/gN antibodies have not been characterized among seroimmune pregnant women. Paired maternal and infant cord sera from 92 CMV seropositive mothers and their full-term or preterm infants were tested for anti-gM/gN antibody titers in comparison with anti-gB titers and neutralizing activity. Anti-gM/gN titers were significantly lower than anti-gB titers for all groups and did not correlate with serum neutralizing capacity. Further study is needed to determine if higher anti-gM/gN antibody titers might enhance serum neutralizing capacity among seropositive adults.

18.
J Child Neurol ; 36(5): 350-356, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33206020

RESUMO

BACKGROUND: Metagenomic next-generation sequencing offers an unbiased approach to identifying viral pathogens in cerebrospinal fluid of patients with meningoencephalitis of unknown etiology. METHODS: In an 11-month case series, we investigated the use of cerebrospinal fluid metagenomic next-generation sequencing to diagnose viral infections among pediatric hospitalized patients presenting with encephalitis or meningoencephalitis of unknown etiology. Cerebrospinal fluid from patients with known enterovirus meningitis were included as positive controls. Cerebrospinal fluid from patients with primary intracranial hypertension were included to serve as controls without known infections. RESULTS: Cerebrospinal fluid metagenomic next-generation sequencing was performed for 37 patients. Among 27 patients with encephalitis or meningoencephalitis, 4 were later diagnosed with viral encephalitis, 6 had non-central nervous system infections with central nervous system manifestations, 6 had no positive diagnostic tests, and 11 were found to have a noninfectious diagnosis. Metagenomic next-generation sequencing identified West Nile virus (WNV) in the cerebrospinal fluid of 1 immunocompromised patient. Among the 4 patients with known enterovirus meningitis, metagenomic next-generation sequencing correctly identified enteroviruses and characterized the viral genotype. No viral sequences were detected in the cerebrospinal fluid of patients with primary intracranial hypertension. Metagenomic next-generation sequencing also identified sequences of nonpathogenic torque Teno virus in cerebrospinal fluid specimens from 13 patients. CONCLUSIONS: Our results showed viral detection by cerebrospinal fluid metagenomic next-generation sequencing only in 1 immunocompromised patient and did not offer a diagnostic advantage over conventional testing. Viral phylogenetic characterization by metagenomic next-generation sequencing could be used in epidemiologic investigations of some viral pathogens, such as enteroviruses. The finding of torque Teno viruses in cerebrospinal fluid by metagenomic next-generation sequencing is of unknown significance but may merit further exploration for a possible association with noninfectious central nervous system disorders.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Meningoencefalite/líquido cefalorraquidiano , Meningoencefalite/virologia , Metagenômica/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Meningoencefalite/genética
19.
J Perinatol ; 41(2): 310-314, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32893264

RESUMO

OBJECTIVE: To determine when infants in the neonatal intensive care unit (NICU) have the first hearing screen performed, and thus inform targeted testing for cytomegalovirus (CMV)-related hearing loss. STUDY DESIGN: Retrospective review of electronic health records of infants admitted to a Level 4 outborn NICU and had a first hearing screen performed from 8/2016-8/2018. RESULT: Among 1498 infants, 546 (36%) had a first hearing screen performed at age >21 days when a positive CMV PCR test cannot distinguish congenital from postnatal CMV acquisition. While most infants tested at >21 days of age were <34 weeks' gestational age (71%), 18% (n = 100) and 11% (n = 59) were ≥34 and ≥37 weeks' gestation, respectively. CONCLUSION: Targeted CMV testing for failed hearing screen in the NICU is problematic as 36% of infants did not have a hearing screen performed before 21 days of age, supporting the need for CMV screening at NICU admission.


Assuntos
Infecções por Citomegalovirus , Unidades de Terapia Intensiva Neonatal , Infecções por Citomegalovirus/diagnóstico , Audição , Humanos , Lactente , Recém-Nascido , Triagem Neonatal , Estudos Retrospectivos
20.
Transplantation ; 105(8): 1718-1729, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33214535

RESUMO

BACKGROUND: Human cytomegalovirus (CMV) infection is associated with renal allograft dysfunction and loss, particularly in combination with acute rejection. Emerging literature suggests that non-HLA antibodies may contribute to antibody-mediated rejection, but pathogen-induced antibodies have not been investigated in this context. This study examines the presence of CMV-induced antibodies in murine CMV (MCMV)-infected renal allografts during acute rejection. METHODS: Intragraft immunoglobulin G (IgG) and complement C3 immunostaining were compared among allogeneic MCMV D-/R-, D+/R-, and D+/R+ renal transplants. Intragraft antibody deposition was examined in B cell-deficient recipients treated with MCMV immune sera. Antibody binding and complement-dependent cytotoxicity (CDC) of D-/R- and D+/R+ sera against infected renal tubular epithelial cells (TECs) were measured in vitro. IgG immunostaining was performed in D+/R+ allografts and native kidneys and in D+/R- allografts treated with ganciclovir to inhibit viral replication. RESULTS: D+/R- and D+/R+ transplants had more abundant IgG and C3 deposition compared with D-/R- recipients. Greater IgG deposition was associated with more severe allograft injury in B cell-deficient recipients treated with MCMV immune sera compared with nonimmune sera. D+/R+ sera induced greater CDC of infected TECs compared with D-/R- sera. Native kidneys had lower IgG deposition compared with allografts, despite similar organ viral loads. Ganciclovir-treated allografts had reduced IgG deposition compared with untreated allografts. CONCLUSIONS: In this murine model, complement-fixing antibodies can deposit into MCMV-infected renal allografts, are associated with allograft damage, and can induce CDC of MCMV-infected renal TECs. The allogeneic response and viral replication may also contribute to intragraft antibody deposition.


Assuntos
Anticorpos Antivirais/análise , Proteínas do Sistema Complemento/imunologia , Infecções por Citomegalovirus/imunologia , Rejeição de Enxerto/imunologia , Transplante de Rim/efeitos adversos , Doença Aguda , Animais , Citotoxicidade Imunológica , Ganciclovir/farmacologia , Imunoglobulina G/análise , Túbulos Renais/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Transplante Homólogo
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