RESUMO
COVID-19, caused by the SARS-COV-2 virus, induces numerous immunological reactions linked to the severity of the clinical condition of those infected. The surface Spike protein (S protein) present in Sars-CoV-2 is responsible for the infection of host cells. This protein presents a high rate of mutations, which can increase virus transmissibility, infectivity, and immune evasion. Therefore, we propose to evaluate, using immunoinformatic techniques, the predicted epitopes for the S protein of seven variants of Sars-CoV-2. MHC class I and II epitopes were predicted and further assessed for their immunogenicity, interferon-gamma (IFN-γ) inducing capacity, and antigenicity. For B cells, linear and structural epitopes were predicted. For class I MHC epitopes, 40 epitopes were found for the clades of Wuhan, Clade 2, Clade 3, and 20AEU.1, Gamma, and Delta, in addition to 38 epitopes for Alpha and 44 for Omicron. For MHC II, there were differentially predicted epitopes for all variants and eight equally predicted epitopes. These were evaluated for differences in the MHC II alleles to which they would bind. Regarding B cell epitopes, 16 were found in the Wuhan variant, 14 in 22AEU.1 and in Clade 3, 15 in Clade 2, 11 in Alpha and Delta, 13 in Gamma, and 9 in Omicron. When compared, there was a reduction in the number of predicted epitopes concerning the Spike protein, mainly in the Delta and Omicron variants. These findings corroborate the need for updates seen today in bivalent mRNA vaccines against COVID-19 to promote a targeted immune response to the main circulating variant, Omicron, leading to more robust protection against this virus and avoiding cases of reinfection. When analyzing the specific epitopes for the RBD region of the spike protein, the Omicron variant did not present a B lymphocyte epitope from position 390, whereas the epitope at position 493 for MHC was predicted only for the Alpha, Gamma, and Omicron variants.
Assuntos
COVID-19 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Humanos , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/química , COVID-19/imunologia , COVID-19/virologia , COVID-19/prevenção & controle , Brasil , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito B/química , Epitopos/imunologia , Epitopos/química , Interferon gama/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/genéticaRESUMO
Major constituents of the plant cell walls are structural proteins that belong to the hydroxyproline-rich glycoprotein (HRGP) family. Leucine-rich repeat extensin (LRX) proteins contain a leucine-rich domain and a C-terminal domain with repetitive Ser-Pro3-5 motifs that are potentially to be O-glycosylated. It has been demonstrated that pollen-specific LRX8-LRX11 from Arabidopsis thaliana are necessary to maintain the integrity of the pollen tube cell wall during polarized growth. In HRGPs, including classical extensins (EXTs), and probably in LRXs, proline residues are converted to hydroxyproline by prolyl-4-hydroxylases (P4Hs), thus defining novel O-glycosylation sites. In this context, we aimed to determine whether hydroxylation and subsequent O-glycosylation of Arabidopsis pollen LRXs are necessary for their proper function and cell wall localization in pollen tubes. We hypothesized that pollen-expressed P4H4 and P4H6 catalyze the hydroxylation of the proline units present in Ser-Pro3-5 motifs of LRX8-LRX11. Here, we show that the p4h4-1 p4h6-1 double mutant exhibits a reduction in pollen germination rates and a slight reduction in pollen tube length. Pollen germination is also inhibited by P4H inhibitors, suggesting that prolyl hydroxylation is required for pollen tube development. Plants expressing pLRX11::LRX11-GFP in the p4h4-1 p4h6-1 background show partial re-localization of LRX11-green fluorescent protein (GFP) from the pollen tube tip apoplast to the cytoplasm. Finally, immunoprecipitation-tandem mass spectrometry analysis revealed a decrease in oxidized prolines (hydroxyprolines) in LRX11-GFP in the p4h4-1 p4h6-1 background compared with lrx11 plants expressing pLRX11::LRX11-GFP. Taken together, these results suggest that P4H4 and P4H6 are required for pollen germination and for proper hydroxylation of LRX11 necessary for its localization in the cell wall of pollen tubes.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Tubo Polínico , Prolil Hidroxilases , Arabidopsis/metabolismo , Arabidopsis/genética , Hidroxilação , Tubo Polínico/crescimento & desenvolvimento , Tubo Polínico/metabolismo , Tubo Polínico/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Prolil Hidroxilases/metabolismo , Prolil Hidroxilases/genética , Parede Celular/metabolismoRESUMO
The variability in the expression of different P-glycoprotein (P-gp) genes in parasitic nematodes of ruminants such as Haemonchus contortus (Hco-pgp) may be caused by different factors including nematode biology, geographical region and anthelmintic pressure. This study analysed the relative expression level of 10 P-gp genes in two H. contortus (Hco-pgp) field isolates from Yucatan, Mexico: 1) PARAISO (IVM-resistant) and 2) FMVZ-UADY (IVM-susceptible). These isolates were compared with a susceptible reference isolate from Puebla, Mexico, namely "CENID-SAI". In all cases H. contortus adult males were used. The Hco-pgp genes (1, 2, 3, 4, 9, 10, 11, 12, 14 and 16) were analysed for each isolate using the RT-qPCR technique. The Hco-pgp expressions were pairwise compared using the 2-ΔΔCt method and a t-test. The PARAISO isolate showed upregulation compared to the CENID-SAI isolate for Hco-pgp 1, 3, 9, 10 and 16 (P < 0.05), and the PARAISO isolate showed upregulation vs. FMVZ-UADY isolate for Hco-pgp 2 and 9 (P < 0.05), displaying 6.58- and 5.93-fold differences (P < 0.05), respectively. In contrast, similar Hco-pgp gene expression levels were recorded for FMVZ-UADY and CENID-SAI isolates except for Hco-pgp1 (P <0.1), which presented a significant upregulation (6.08-fold). The relative expression of Hco-pgp allowed confirming the IVM-resistant status of the PARAISO isolate and the IVM-susceptible status of the FMVZ-UADY isolate when compared to the CENID-SAI reference isolate. Therefore, understanding the association between the Hco-pgp genes expression of H. contortus and its IVM resistance status could help identifying the genes that could be used as molecular markers in the diagnosis of IVM resistance. However, it is important to consider the geographic origin of the nematode isolate and the deworming history at the farm of origin.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Resistência a Medicamentos , Hemoncose , Haemonchus , Ivermectina , Animais , Haemonchus/efeitos dos fármacos , Haemonchus/genética , Ivermectina/farmacologia , México , Masculino , Resistência a Medicamentos/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Hemoncose/veterinária , Hemoncose/parasitologia , Fenótipo , Anti-Helmínticos/farmacologia , Expressão Gênica , Doenças dos Ovinos/parasitologia , OvinosRESUMO
Follicle-stimulating hormone (FSH) is an important protein used for bovine ovarian hyperstimulation in multiple ovulation and embryo transfer technology (MOET). Several attempts to produce bovine FSH (bFSH) in recombinant systems have been reported, nonetheless, up to date, the most commonly used products are partially purified preparations derived from porcine or ovine (pFSH or oFSH) pituitaries. Here we describe the development of a biotechnology process to produce a novel, hyperglycosylated, long-acting recombinant bFSH (LA-rbFSH) by fusing copies of a highly O-glycosylated peptide. LA-rbFSH and a nonmodified version (rbFSH) were produced in suspension CHO cell cultures and purified by IMAC with high purity levels (>99%). LA-rbFSH presented a higher glycosylation degree and sialic acid content than rbFSH. It also demonstrated a notable improvement in pharmacokinetic properties after administration to rats, including a higher concentration in plasma and a significant (seven-fold) reduction in apparent clearance (CLapp). In addition, the in vivo specific bioactivity of LA-rbFSH in rats was 2.4-fold higher compared to rbFSH. These results postulate this new molecule as an attractive substitute for commercially available porcine pituitary-derived products.
Assuntos
Cricetulus , Hormônio Foliculoestimulante , Proteínas Recombinantes , Animais , Hormônio Foliculoestimulante/metabolismo , Células CHO , Glicosilação , Bovinos , Ratos , Feminino , Biotecnologia/métodosRESUMO
Objective: To identify the incidence of in-hospital major adverse cardiac events (MACE) with the use of mechanic thromboaspiration plus IIb/IIIa glycoprotein inhibitors versus only use of IIb/IIIa glycoprotein inhibitors on patients with acute ST elevation myocardial infarction. Method: Retrospective, observational, cohort analytic study, on patients with acute ST elevation myocardial infarction that had angiography thrombus TIMI 5 grade, treated between October 2021 and December 2022. Results: A total of 237 patients were included. In 113 patients thromboaspiration were used, 124 patients didn't used. 81.6% were men. In-hospital MACE occurred on 31.9% of patients with thromboaspiration use vs. 30.6% on patients with no use (RR: 1.05; IC95%: 0.61-1.93; p = 0.840). Incidence of malignant arrhythmias were of 8% with thromboaspiration use vs. 1.6% on patients with no use (RR: 5.27; IC95%: 1.11-24.97; p = 0.020). Conclusions: The use of thromboaspiration on concomitant treatment with IIb/IIIa glycoprotein inhibitors was similar with only IIb/IIIa glycoprotein inhibitors in reducing incidence of in-hospital MACE on patients with ST elevation acute myocardial infarction and high thrombus burden. The study has several limitations, so results should be taken with caution.
Objetivo: Identificar la incidencia de eventos cardiovasculares adversos mayores (ECAM) intrahospitalarios con el uso de tromboaspiración mecánica más inhibidores de la glucoproteína IIb/IIIa contra solo inhibidores de la glucoproteína IIb/IIIa en pacientes con infarto agudo al miocardio con elevación del segmento ST (IAMCEST). Método: Estudio retrospectivo, observacional, analítico, de cohorte, en pacientes con IAMCEST con trombo angiográfico de grado TIMI 5, tratados entre octubre de 2021 y diciembre de 2022. Resultados: Cumplieron los criterios de inclusión 237 pacientes. En 113 se usó tromboaspirador más inhibidores IIb/IIIa y en 124 solo inhibidores IIb/IIIa. El 81.6% fueron hombres. La incidencia de ECAM intrahospitalarios fue del 31.9% en los pacientes con tromboaspiración y del 30.6% en los pacientes con solo inhibidores IIb/IIIa (RR: 1.05; IC95%: 0.61-1.93; p = 0.840). La incidencia de arritmias graves fue del 8% en los pacientes con tromboaspiración y del 1.6% en los pacientes con solo inhibidores IIb/IIIa (RR: 5.27; IC95%: 1.11-24.97; p = 0.020). Conclusiones: La frecuencia de ECAM asociados al uso de tromboaspiración mecánica como coadyuvante a los inhibidores de la glucoproteína IIb/IIIa en pacientes con IAMCEST y trombo angiográfico de grado TIMI 5 no es diferente de la de aquellos pacientes en las que solo se utilizan inhibidores de la glucoproteína IIb/IIa. El estudio tiene varias limitaciones, por lo que los resultados deben tomarse con cautela.
RESUMO
The worldwide spread of SARS-CoV-2 has led to a significant economic and social burden on a global scale. Even though the pandemic has concluded, apprehension remains regarding the emergence of highly transmissible variants capable of evading immunity induced by either vaccination or prior infection. The success of viral penetration is due to the specific amino acid residues of the receptor-binding motif (RBM) involved in viral attachment. This region interacts with the cellular receptor ACE2, triggering a neutralizing antibody (nAb) response. In this study, we evaluated serum immunogenicity from individuals who received either a single dose or a combination of different vaccines against the original SARS-CoV-2 strain and a mutated linear RBM. Despite a modest antibody response to wild-type SARS-CoV-2 RBM, the Omicron variants exhibit four mutations in the RBM (S477N, T478K, E484A, and F486V) that result in even lower antibody titers. The primary immune responses observed were directed toward IgA and IgG. While nAbs typically target the RBD, our investigation has unveiled reduced seroreactivity within the RBD's crucial subregion, the RBM. This deficiency may have implications for the generation of protective nAbs. An evaluation of S1WT and S2WT RBM peptides binding to nAbs using microscale thermophoresis revealed a higher affinity (35 nM) for the S2WT sequence (GSTPCNGVEGFNCYF), which includes the FNCY patch. Our findings suggest that the linear RBM of SARS-CoV-2 is not an immunodominant region in vaccinated individuals. Comprehending the intricate dynamics of the humoral response, its interplay with viral evolution, and host genetics is crucial for formulating effective vaccination strategies, targeting not only SARS-CoV-2 but also anticipating potential future coronaviruses.
RESUMO
To date, limited information is available on cytomegalovirus (CMV) and lymphocryptovirus (LCV) from Chlorocebus monkeys. We report here high detection rates of herpesviruses in free-roaming African green monkeys (AGMs, Chlorocebus sabaeus) (26.4%, 23/87) and in captive AGMs (75%, 3/4) with respiratory disease on the Caribbean Island of St. Kitts. LCV (81.25%) was more prevalent than CMV (18.75%) in the AGMs. Applying a bigenic PCR approach (targeting DNA polymerase (DPOL) and glycoprotein B (gB) genes), long sequences were obtained from representative AGM CMV (KNA-SD6) and LCV (KNA-E4, -N6 and -R15) samples, and mixed LCV infections were identified in KNA-N6 and -R15. The nucleotide (nt) sequence (partial DPOL-intergenic region-partial gB) and partial DPOL- and gB-amino acid (aa) sequences of AGM CMV KNA-SD6 were closely related to Cytomegalovirus cercopithecinebeta5 isolates from grivet monkeys, whilst those of AGM LCV KNA-E4 and -N6 (and E4-like gB of KNA-R15) were more closely related to cognate sequences of erythrocebus patas LCV1 from patas monkey than other LCVs, corroborating the concept of cospeciation in the evolution of CMV/LCV. On the other hand, the partial DPOL aa sequence of KNA-R15, and additional gB sequences (N6-gB-2 and R15-gB-2) from samples KNA-N6 and -R15 (respectively) appeared to be distinct from those of Old World monkey LCVs, indicating LCV evolutionary patterns that were not synchronous with those of host species. The present study is the first to report the molecular prevalence and genetic diversity of CMV/LCV from free-roaming/wild and captive AGMs, and is the first report on analysis of CMV nt/deduced aa sequences from AGMs and LCV gB sequences from Chlorocebus monkeys.
Assuntos
Infecções por Citomegalovirus , Lymphocryptovirus , Animais , Chlorocebus aethiops , Lymphocryptovirus/genética , Citomegalovirus/genética , Filogenia , Herpesvirus Humano 4 , Glicoproteínas/genética , Variação GenéticaRESUMO
BACKGROUND: The current challenge in clinical cancer treatment is chemoresistance. Colon cells have inherently higher xenobiotic transporters expression and hence can attain resistance rapidly. Increased levels of TGF-ß2 expression in patients have been attributed to cancer progression, aggressiveness, and resistance. To investigate resistance progression, we treated doxorubicin (dox) to HT-29 colon adenocarcinoma cells in the presence or absence of TGF-ß2 ligand. METHODS: After 1, 3-, and 7-day treatment, we investigated cell proliferation, viability, and cytotoxicity by MTT, trypan blue staining, and lactate dehydrogenase enzyme release. The mechanism of cell death was elucidated by hoechst33342 and propidium iodide dual staining and apoptosis assay. The development of resistance was detected by rhodamine123 efflux and P-glycoprotein (P-gp)/MDR1 antibody staining through fluorimetry and flow cytometry. The colony formation ability of the cells was also elucidated. RESULTS: Inhibition of cell proliferation was noted after day 1, while a significant reduction in viability and a significant increase in lactate dehydrogenase release was detected after day 3. Reduction of intracellular rhodamine123 levels was detected after day 3 and was significantly lower in dox with TGF-ß2 treatment compared to dox alone. Increased surface P-gp levels after days 3 and 7 were observed in the treated groups. Hoechst33342/propidium iodide staining and apoptosis assay indicated non-apoptotic cell death. The cells treated with TGF-ß2 had higher colony formation ability. CONCLUSIONS: TGF-ß2 expression might play a significant role in the development of chemoresistance to doxorubicin in Duke's type B colon adenocarcinoma cell line, HT-29.
Assuntos
Adenocarcinoma , Antibióticos Antineoplásicos , Apoptose , Proliferação de Células , Neoplasias do Colo , Doxorrubicina , Resistencia a Medicamentos Antineoplásicos , Fator de Crescimento Transformador beta2 , Humanos , Doxorrubicina/farmacologia , Adenocarcinoma/patologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Neoplasias do Colo/patologia , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Fator de Crescimento Transformador beta2/metabolismo , Antibióticos Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Células HT29 , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacosRESUMO
Orosomucoid, or alpha-1 acid glycoprotein (AGP), is a major acute-phase protein expressed in response to systemic injury and inflammation. AGP has been described as an inhibitor of neutrophil migration on sepsis, particularly its immunomodulation effects. AGP's biological functions in coronavirus disease 2019 (COVID-19) are not understood. We sought to investigate the role of AGP in severe COVID-19 infection patients and neutrophils infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Epidemiological data, AGP levels, and other laboratory parameters were measured in blood samples from 56 subjects hospitalized in the ICU with SARS-CoV-2 infection. To evaluate the role of AGP in NETosis in neutrophils, blood samples from health patients were collected, and neutrophils were separated and infected with SARS-CoV-2. Those neutrophils were treated with AGP or vehicle, and NETosis was analyzed by flow cytometry. AGP was upregulated in severe COVID-19 patients (p<0.05). AGP level was positively correlated with IL-6 and C-reactive protein (respectively, p=0.005, p=0.002) and negatively correlated with lactate (p=0.004). AGP treatment downregulated early and late NETosis (respectively, 35.7% and 43.5%) in neutrophils infected with SARS-CoV-2 and up-regulated IL-6 supernatant culture expression (p<0.0001). Our data showed increased AGP in COVID-19 infection and contributed to NETosis regulation and increased IL-6 production, possibly related to the Cytokine storm in COVID-19.
Assuntos
COVID-19 , Humanos , COVID-19/metabolismo , Neutrófilos/metabolismo , Orosomucoide/metabolismo , Orosomucoide/farmacologia , SARS-CoV-2 , Interleucina-6/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Imunoproteínas/metabolismoRESUMO
Saint Louis encephalitis virus (SLEV) infection is an arbovirosis associated with a broad spectrum of neurological complications. We present a case of a 55-year-old man hailing from Manaus, a city situated in the heart of the Amazon Rainforest, who exhibited symptoms of vertigo, tremors, urinary and fecal retention, compromised gait, and encephalopathy 3 weeks following SLEV infection. Neuroaxis MRI revealed diffuse, asymmetric, and poorly defined margins hyperintense lesions with peripheral and ring enhancement in subcortical white matter, as well as severe spinal cord involvement. Serology for SLEV was positive both on serum and cerebrospinal fluid. To the best of our knowledge, the present report is the first to show brain lesions along with myelitis as a post-infectious complication of SLEV infection.