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1.
Int J Immunogenet ; 51(1): 39-46, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38087909

RESUMEN

Human leukocyte antigen-G (HLA-G) is classified as non-classical HLA, located in the short arm of chromosome 6 and composed of seven introns and eight exons. The HLA-G gene has a lower frequency polymorphism in the coding area and higher variability at the regulatory 5'- and 3'-untranslated regions linked to HLA-G microRNA regulation. HLA-G molecule is known to have an immunomodulatory and tolerogenic features role. In 199 Saudi individuals, we examined the association between plasma soluble HLA-G (sHLA-G) levels and eight polymorphic different sites, including 14 bp ins/del/+3003T-C/+3010C-G/+3027C-A/+3035C-T/+3142C-G/+3187A-G/+3196C-G single nucleotide polymorphisms (SNPs) in exon 8 in the HLA-G gene. Our results revealed higher frequency for rs17179101C (97%), rs1707T (92%) and rs9380142A (73%) alleles. Greater frequencies for the tested genotypes were observed in 3027C/C (rs17179101) (93%), 14 bp (rs1704) ins/del (92%), +3003T/T (rs1707) (85%) and +3035C/T (rs17179108) (79%) SNP genotypes. Moreover, we observed a significant association of sHLA-G with +3010G/C (rs1710) SNP. In conclusion, we showed a significant association between 3010G/C (rs1710) SNP and the sHLA-G level among our sample for Saudi populations. Our findings demonstrated that specific SNP within the HLA-G gene is linked to sHLA-G molecule secretion, suggesting sHLA-G levels may be regulated genetically.


Asunto(s)
Antígenos HLA-G , Polimorfismo de Nucleótido Simple , Humanos , Antígenos HLA-G/genética , Genotipo , Regiones no Traducidas 3'/genética , Antígenos de Histocompatibilidad Clase II/genética , Frecuencia de los Genes
2.
J Immunoassay Immunochem ; 45(3): 271-291, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38551181

RESUMEN

Rhinoviruses (RV) are the major cause of chronic obstructive pulmonary disease and are associated with exacerbation development as well as community-acquired pneumonia in children, leading to substantial morbidity, mortality, and hospital admission. Here we have examined how changes at the amino terminal of the conserved VP4 epitope of different RV serotypes may affect pulmonary cytokine and chemokine responses and disease severity. Samples positive for rhinovirus were used for genetic characterization, followed by profiling gene expression of pulmonary Th1 and Th2 cytokines/chemokines by RT-PCR arrays. Genetic sequencing and homology 3D modeling revealed changes at the amino terminal of the conserved viral protein 4 (VP4) epitope in the RV-A101 serotype, especially serine at several positions that are important for interactive binding with the host immune cells. We found dysregulation of pulmonary gene expression of Th1- and Th2-related cytokines and chemokines in RV-A 101 and RV-C 8 pneumonia patients. These findings might contribute to a better understanding of RV immunity and the potential mechanisms underlying the pathogenesis of severe RV infections, but further functional studies are needed to confirm the causal relationship.


Asunto(s)
Rhinovirus , Humanos , Rhinovirus/genética , Rhinovirus/inmunología , Proteínas de la Cápside/genética , Proteínas de la Cápside/inmunología , Proteínas de la Cápside/química , Citocinas/inmunología , Citocinas/genética , Femenino , Masculino , Infecciones por Picornaviridae/inmunología , Infecciones por Picornaviridae/genética , Infecciones por Picornaviridae/virología , Células Th2/inmunología
3.
J Immunoassay Immunochem ; 44(1): 13-30, 2023 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-35915975

RESUMEN

There are limited data on inflammatory cytokines and chemokines; the humoral immune response; and main clinical laboratory parameters as indicators for disease severity and mortality in patients with critical and mild COVID-19 without comorbidities or immune-mediated diseases in Saudi Arabia. We determined the expression levels of major proinflammatory cytokines and chemokines; C-reactive protein (CRP); procalcitonin; SARS-CoV-2 IgM antibody and twenty-two clinical laboratory parameters and assessed their usefulness as indicators of disease severity and in-hospital death. Our results showed a significant increase in the expression levels of SARS-CoV-2 IgM antibody; IL1-ß; IL-6; IL-8; TNF-α and CRP in critical COVID-19 patients; neutrophil count; urea; creatinine and troponin were also increased. The elevation of these biomarkers was significantly associated and positively correlated with in-hospital death in critical COVID-19 patients. Our results suggest that the levels of IL1-ß; IL-6; IL-8; TNF-α; and CRP; neutrophil count; urea; creatinine; and troponin could be used to predict disease severity in COVID-19 patients without comorbidities or immune-mediated diseases. These inflammatory mediators could be used as predictive early biomarkers of COVID-19 disease deterioration; shock and death among COVID-19 patients without comorbidities or immune-mediated diseases.


Asunto(s)
COVID-19 , Mortalidad Hospitalaria , Humanos , Biomarcadores , Proteína C-Reactiva , COVID-19/diagnóstico , COVID-19/mortalidad , Creatinina , Citocinas , Interleucina-6 , Interleucina-8 , Gravedad del Paciente , SARS-CoV-2 , Troponina , Factor de Necrosis Tumoral alfa , Quimiocinas
4.
Curr Issues Mol Biol ; 44(12): 6117-6131, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36547078

RESUMEN

The COVID-19 pandemic necessitated an extensive testing for active SARS-CoV-2 infection. However, securing affordable diagnostic tests is a struggle for low-resource settings. We report herein the development and validation of an in-house multiplex real-time RT-PCR diagnostic test for the detection of active COVID-19 infection (ScriptTaq COVID PCR). Furthermore, we describe two methods for RNA extraction using either an in-house silica column or silica-coated magnetic beads to replace commercial RNA extraction kits. Different buffer formulations for silica column and silica-coated magnetic beads were tested and used for RNA isolation. Taq polymerase enzyme and thermostable reverse transcriptase enzyme were purified from bacterial clones. Primers/probes sequences published by the WHO and CDC were used for the qualitative detection of the RNA-dependent RNA polymerase (RdRp) and nucleocapsid (N) genes, respectively. ScriptTaq COVID PCR assay was able to detect up to 100 copies per reaction of the viral RdRP and N genes. The test demonstrated an overall agreement of 95.4%, a positive percent agreement (PPA) of 90.2%, and a negative percent agreement (NPA) of 100.0% when compared with two commercially available kits. ScriptTaq COVID PCR diagnostic test is a specific, sensitive, and low-cost alternative for low-resource settings.

5.
J Clin Immunol ; 41(7): 1607-1620, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34232441

RESUMEN

The complement system, a network of highly-regulated proteins, represents a vital part of the innate immune response. Over-activation of the complement system plays an important role in inflammation, tissue damage, and infectious disease severity. The prevalence of MERS-CoV in Saudi Arabia remains significant and cases are still being reported. The role of complement in Middle East Respiratory Syndrome coronavirus (MERS-CoV) pathogenesis and complement-modulating treatment strategies has received limited attention, and studies involving MERS-CoV-infected patients have not been reported. This study offers the first insight into the pulmonary expression profile including seven complement proteins, complement regulatory factors, IL-8, and RANTES in MERS-CoV infected patients without underlying chronic medical conditions. Our results significantly indicate high expression levels of complement anaphylatoxins (C3a and C5a), IL-8, and RANTES in the lungs of MERS-CoV-infected patients. The upregulation of lung complement anaphylatoxins, C5a, and C3a was positively correlated with IL-8, RANTES, and the fatality rate. Our results also showed upregulation of the positive regulatory complement factor P, suggesting positive regulation of the complement during MERS-CoV infection. High levels of lung C5a, C3a, factor P, IL-8, and RANTES may contribute to the immunopathology, disease severity, ARDS development, and a higher fatality rate in MERS-CoV-infected patients. These findings highlight the potential prognostic utility of C5a, C3a, IL-8, and RANTES as biomarkers for MERS-CoV disease severity and mortality. To further explore the prediction of functional partners (proteins) of highly expressed proteins (C5a, C3a, factor P, IL-8, and RANTES), the computational protein-protein interaction (PPI) network was constructed, and six proteins (hub nodes) were identified.


Asunto(s)
Quimiocina CCL5/genética , Quimiocina CCL5/metabolismo , Complemento C3a/metabolismo , Complemento C5a/metabolismo , Infecciones por Coronavirus/diagnóstico , Interleucina-8/metabolismo , Pulmón/metabolismo , Coronavirus del Síndrome Respiratorio de Oriente Medio/fisiología , Anciano , Biomarcadores/metabolismo , Complemento C3a/genética , Complemento C5a/genética , Infecciones por Coronavirus/metabolismo , Infecciones por Coronavirus/mortalidad , Femenino , Humanos , Interleucina-8/genética , Masculino , Persona de Mediana Edad , Pronóstico , Índice de Severidad de la Enfermedad , Análisis de Supervivencia , Regulación hacia Arriba
6.
Virol J ; 18(1): 127, 2021 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-34127006

RESUMEN

BACKGROUND: In COVID-19 patients, undetected co-infections may have severe clinical implications associated with increased hospitalization, varied treatment approaches and mortality. Therefore, we investigated the implications of viral and bacterial co-infection in COVID-19 clinical outcomes. METHODS: Nasopharyngeal samples were obtained from 48 COVID-19 patients (29% ICU and 71% non-ICU) and screened for the presence of 24 respiratory pathogens using six multiplex PCR panels. RESULTS: We found evidence of co-infection in 34 COVID-19 patients (71%). Influenza A H1N1 (n = 17), Chlamydia pneumoniae (n = 13) and human adenovirus (n = 10) were the most commonly detected pathogens. Viral co-infection was associated with increased ICU admission (r = 0.1) and higher mortality (OR 1.78, CI = 0.38-8.28) compared to bacterial co-infections (OR 0.44, CI = 0.08-2.45). Two thirds of COVID-19 critically ill patients who died, had a co-infection; and Influenza A H1N1 was the only pathogen for which a direct relationship with mortality was seen (r = 0.2). CONCLUSIONS: Our study highlights the importance of screening for co-infecting viruses in COVID-19 patients, that could be the leading cause of disease severity and death. Given the high prevalence of Influenza co-infection in our study, increased coverage of flu vaccination is encouraged to mitigate the transmission of influenza virus during the on-going COVID-19 pandemic and reduce the risk of severe outcome and mortality.


Asunto(s)
COVID-19/mortalidad , Coinfección/mortalidad , Gripe Humana/mortalidad , Adulto , Anciano , Infecciones Bacterianas/epidemiología , Infecciones Bacterianas/mortalidad , Infecciones Bacterianas/patología , COVID-19/epidemiología , COVID-19/patología , Coinfección/epidemiología , Coinfección/patología , Femenino , Hospitalización , Humanos , Subtipo H1N1 del Virus de la Influenza A/aislamiento & purificación , Gripe Humana/epidemiología , Gripe Humana/patología , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Nasofaringe/microbiología , Nasofaringe/virología , Prevalencia , SARS-CoV-2/aislamiento & purificación , Arabia Saudita/epidemiología
7.
J Med Virol ; 92(12): 3016-3027, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32159230

RESUMEN

Antigenic drift of the hemagglutinin (HA) and neuraminidase (NA) proteins of the influenza virus cause a decrease in vaccine efficacy. Since the information about the evolution of these viruses in Saudi is deficient so we investigated the genetic diversity of circulating H1N1 viruses. Nasopharyngeal aspirates/swabs collected from 149 patients hospitalized with flu-like symptoms during 2014 and 2015 were analyzed. Viral RNA extraction was followed by a reverse transcription-polymerase chain reaction and genetic sequencing. We analyzed complete gene sequences of HA and NA from 80 positive isolates. Phylogenetic analysis of HA and NA genes of 80 isolates showed similar topologies and co-circulation of clades 6b. Genetic diversity was observed among circulating viruses belonging to clade 6B.1A. The amino acid residues in the HA epitope domain were under purifying selection. Amino acid changes at key antigenic sites, such as position S101N, S179N (antigenic site-Sa), I233T (antigenic site-Sb) in the head domain might have resulted in antigenic drift and emergence of variant viruses. For NA protein, 36% isolates showed the presence of amino acid changes such as V13I (n = 29), I314M (n = 29) and 12% had I34V (n = 10). However, H257Y mutation responsible for resistance to neuraminidase inhibitors was missing. The presence of amino acid changes at key antigenic sites and their topologies with structural mapping of residues under purifying selection highlights the importance of antigenic drift and warrants further characterization of recently circulating viruses in view of vaccine effectiveness. The co-circulation of several clades and the predominance of clade 6B.1 suggest multiple introductions in Saudi.

8.
Cytokine ; 126: 154895, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31706200

RESUMEN

MERS-CoV, a highly pathogenic virus in humans, is associated with high morbidity and case fatality. Inflammatory responses have a significant impact on MERS-CoV pathogenesis and disease outcome. However, CD4+ T-cell induced immune responses during acute MERS-CoV infection are barely detectable, with potent inhibition of effector T cells and downregulation of antigen presentation. The local pulmonary immune response, particularly the Th1 and Th2-related immune response during acute severe MERS-CoV infection is not fully understood. In this study, we offer the first insights into the pulmonary gene expression profile of Th1 and Th2-related cytokines/chemokines (Th1 & Th2 responses) during acute MERS-CoV infection using RT2 Profiler PCR Arrays. We also quantified the expression level of primary inflammatory cytokines/chemokines. Our results showed a downregulation of Th2, inadequate (partial) Th1 immune response and high expression levels of inflammatory cytokines IL-1α and IL-1ß and the neutrophil chemoattractant chemokine IL-8 (CXCL8) in the lower respiratory tract of MERS-CoV infected patients. Moreover, we identified a high viral load in all included patients. We also observed a correlation between inflammatory cytokines, Th1, and Th2 downregulation and the case fatality rate. Th1 and Th2 response downregulation, high expression of inflammatory cytokines, and high viral load may contribute to lung inflammation, severe infection, the evolution of pneumonia and ARDS, and a higher case fatality rate. Further study of the molecular mechanisms underlying the Th1 and Th2 regulatory pathways will be vital for active vaccine development and the identification of novel therapeutic strategies.


Asunto(s)
Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/patología , Citocinas/sangre , Coronavirus del Síndrome Respiratorio de Oriente Medio/inmunología , Células TH1/inmunología , Células Th2/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Bronquios/inmunología , Bronquios/patología , Bronquios/virología , Infecciones por Coronavirus/mortalidad , Citocinas/genética , Citocinas/inmunología , Regulación hacia Abajo/genética , Regulación hacia Abajo/inmunología , Femenino , Humanos , Inmunidad Innata/genética , Inmunidad Innata/inmunología , Inflamación/genética , Inflamación/inmunología , Masculino , Persona de Mediana Edad , Carga Viral , Replicación Viral/inmunología
9.
J Med Virol ; 86(4): 672-7, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24374981

RESUMEN

Although subclinical persistent infections with the human polyomaviruses BKV and JCV are ubiquitous worldwide, these are known to vary in relation to diseases present and geographical location. DNAs from 220 cervical smears and 109 invasive cervical carcinomas obtained from HIV positive and HIV negative Kenyan women of known HPV status were analyzed by nested endpoint PCR for BKV and JCV. BKV-JCV DNA was detected in 5/105 (4.7%) of cervical smears and in 6/37 (16%) of cervical carcinomas from women infected with HIV whereas 9/115 (7.8%) of the cervical smears and 4/72 (5.5%) of the carcinomas were positive in HIV negative women. Nested PCR showed that all 24 samples were positive for JCV and not BKV. JCV was not more prevalent in either HPV positive (P = 0.438) or HPV negative women (P = 0.392). However, 37% of carcinomas and smears which were positive for JCV were also positive for a "high-risk" oncogenic HPV. Comparison of the incidence of JCV in cervical smears and cervical carcinomas showed a ∼3-fold increase in samples from HIV positive women with cervical carcinoma (P = 0.025) whereas no significant difference was found between cervical smears and cervical carcinomas from HIV negative women (P = 0.553). These results suggest that JCV may combine with high-risk HPV infection in women infected with HIV to influence the rate of progression to invasive cervical carcinoma.


Asunto(s)
Infecciones por VIH/epidemiología , Virus JC/genética , Infecciones por Polyomavirus/epidemiología , Infecciones Tumorales por Virus/epidemiología , Neoplasias del Cuello Uterino/virología , Adulto , Alphapapillomavirus/genética , Alphapapillomavirus/patogenicidad , Virus BK/genética , Virus BK/patogenicidad , ADN Viral/análisis , Femenino , Infecciones por VIH/virología , Humanos , Virus JC/patogenicidad , Persona de Mediana Edad , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/virología , Neoplasias del Cuello Uterino/epidemiología , Frotis Vaginal , Adulto Joven
10.
Infect Genet Evol ; 120: 105586, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38508363

RESUMEN

EBV latent membrane protein 1 (LMP-1) is an important oncogene involved in the induction and maintenance of EBV infection and the activation of several cell survival and proliferative pathways. The genetic diversity of LMP-1 has an important role in immunogenicity and tumorigenicity allowing escape from host cell immunity and more metastatic potential of LMP-1 variants. This study explored the evolutionary of LMP-1 in EBV-infected patients at an advanced stage of nasopharyngeal carcinoma (NPC). Detection of genetic variability in LMP-1 genes was carried out using Sanger sequencing. Bioinformatic analysis was conducted for translation and nucleotide alignment. Phylogenetic analysis was used to construct a Bayesian tree for a deeper understanding of the genetic relationships, evolutionary connections, and variations between sequences. Genetic characterization of LMP-1 in NPC patients revealed the detection of polymorphism in LMP-1 Sequences. Motifs were identified within three critical LMP-1 domains, such as PQQAT within CTAR1 and YYD within CTAR2. The presence of the JACK3 region at specific sites within CTAR3, as well as repeat regions at positions (122-132) and (133-143) within CTAR3, was also annotated. Additionally, several mutations were detected including 30 and 69 bp deletions, 33 bp repeats, and 15 bp insertion. Although LMP-1 strains appear to be genetically diverse, they are closely related to 3 reference strains: prototype B95.8, Med- 30 bp deletion, and Med + 30 bp deletion. In our study, one of the strains harboring the 30 bp deletion had both bone and bone marrow metastasis which could be attributed to the fact that LMP-1 is involved in tumor metastasis, evasion and migration of NPC cells. This study provided valuable insights into genetic variability in LMP-1 sequences of EBV in NPC patients. Further functional studies would provide a more comprehensive understanding of the molecular characteristics, epidemiology, and clinical implications of LMP-1 polymorphisms in EBV-related malignancies.


Asunto(s)
Biología Computacional , Infecciones por Virus de Epstein-Barr , Variación Genética , Herpesvirus Humano 4 , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Filogenia , Proteínas de la Matriz Viral , Proteínas de la Matriz Viral/genética , Humanos , Carcinoma Nasofaríngeo/virología , Carcinoma Nasofaríngeo/genética , Infecciones por Virus de Epstein-Barr/virología , Herpesvirus Humano 4/genética , Neoplasias Nasofaríngeas/virología , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patología , Biología Computacional/métodos , Evolución Molecular , Teorema de Bayes , Masculino
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