RESUMO
MicroRNAs (miRNAs) play important roles in the control of HIV-1 infection. Here, we performed RNA-seq profiling of miRNAs and mRNAs expressed in CD4+ T lymphocytes upon HIV-1 infection. Our results reveal significant alterations in miRNA and mRNA expression profiles in infected relative to uninfected cells. One of the miRNAs markedly downregulated in infected cells is miRNA-26a. Among the putative targets of miRNA-26a are CD59 receptor transcripts, which are significantly upregulated in infected CD4+ T cells. The addition of miRNA-26a mimics to CD4+ T cells reduces CD59 at both the mRNA and surface protein levels, validating CD59 as a miRNA-26a target. Consistent with the reported inhibitory role of CD59 in complement-mediated lysis (CML), knocking out CD59 in CD4+ T cells renders both HIV-1-infected cells and progeny virions more prone to antibody-dependent CML (ADCML). The addition of miRNA-26a mimics to infected cells leads to enhanced sensitivity of progeny virions to ADCML, a condition linked to a reduction in CD59 packaging into released virions. Lastly, HIV-1-mediated downregulation of miRNA-26a expression is shown to be dependent on integrated HIV-1 expression but does not involve viral accessory proteins. Overall, these results highlight a novel mechanism by which HIV-1 limits ADCML by upregulating CD59 expression via miRNA-26a downmodulation.
Assuntos
Linfócitos T CD4-Positivos , Antígenos CD59 , Regulação para Baixo , Infecções por HIV , HIV-1 , MicroRNAs , Antígenos CD59/genética , Antígenos CD59/metabolismo , Antígenos CD59/imunologia , MicroRNAs/genética , MicroRNAs/metabolismo , MicroRNAs/imunologia , HIV-1/imunologia , HIV-1/fisiologia , HIV-1/genética , Humanos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , Infecções por HIV/genética , Montagem de Vírus , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Proteínas do Sistema Complemento/imunologiaRESUMO
According to single-molecule localisation microscopy almost all plasma membrane proteins are clustered. We demonstrate that clusters can arise from variations in membrane topography where the local density of a randomly distributed membrane molecule to a degree matches the variations in the local amount of membrane. Further, we demonstrate that this false clustering can be differentiated from genuine clustering by using a membrane marker to report on local variations in the amount of membrane. In dual colour live cell single molecule localisation microscopy using the membrane probe DiI alongside either the transferrin receptor or the GPI-anchored protein CD59, we found that pair correlation analysis reported both proteins and DiI as being clustered, as did its derivative pair correlation-photoactivation localisation microscopy and nearest neighbour analyses. After converting the localisations into images and using the DiI image to factor out topography variations, no CD59 clusters were visible, suggesting that the clustering reported by the other methods is an artefact. However, the TfR clusters persisted after topography variations were factored out. We demonstrate that membrane topography variations can make membrane molecules appear clustered and present a straightforward remedy suitable as the first step in the cluster analysis pipeline.
Assuntos
Antígenos CD59 , Membrana Celular , Receptores da Transferrina , Imagem Individual de Molécula , Imagem Individual de Molécula/métodos , Membrana Celular/metabolismo , Antígenos CD59/metabolismo , Receptores da Transferrina/metabolismo , Humanos , Proteínas de Membrana/metabolismo , Análise por Conglomerados , Microscopia de Fluorescência/métodosRESUMO
BACKGROUND: Genome-wide association studies (GWAS) have revealed numerous loci associated with multiple sclerosis (MS). However, the challenge lies in deciphering the mechanisms by which these loci influence the target traits. Here, we employed an integrative analytical pipeline to efficiently transform genetic associations to identify novel proteins for MS. METHODS: We systematically integrated MS GWAS data (N = 115,803) with human plasma proteome data (N = 7213) and conducted proteome-wide association studies (PWAS) to identify MS-associated pathogenic proteins. Following this, we employed Mendelian randomization and Bayesian colocalization analyses to verify the causal relationship between these significant plasma proteins and MS. Lastly, we utilized the Drug-Gene Interaction Database (DGIdb) to identify potential drug targets for MS. RESULTS: The PWAS identified 25 statistically significant cis-regulated plasma proteins associated with MS at a false discovery rate of P < 0.05. Further analysis revealed that the abundance of 7 of these proteins (PLEK, TNXB, CASP3, CD59, CR1, TAPBPL, ATXN3) was causally related to the incidence of MS. Our findings indicated that genetically predicted higher levels of TNXB and CD59 were associated with a lower risk of MS, whereas higher levels of PLEK, CASP3, CR1, TAPBPL, and ATXN3 were associated with an increased risk of MS. Three plasma proteins (PLEK, CR1, CD59) were validated by colocalization analysis. Among these, CR1 was prioritized as a target for Eculizumab due to its significant association with MS risk. Additionally, PLEK, CR1, and CD59 were identified as druggable target genes. CONCLUSIONS: Our proteomic analysis has identified PLEK, CR1, and CD59 as potential drug targets for MS treatment. Developing pharmacological inducers or inhibitors for these proteins could pave the way for new therapeutic approaches, potentially improving outcomes for MS patients.
Assuntos
Estudo de Associação Genômica Ampla , Esclerose Múltipla , Proteoma , Humanos , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/genética , Esclerose Múltipla/sangue , Teorema de Bayes , Proteínas Sanguíneas/metabolismo , Proteínas Sanguíneas/genética , Análise da Randomização Mendeliana , Antígenos CD59/genética , Predisposição Genética para Doença , Proteômica/métodosRESUMO
BACKGROUND: CD59 deficiency due to rare germline variants in the CD59 gene causes disabilities, ischemic strokes, neuropathy, and hemolysis. CD59 deficiency due to common somatic variants in the PIG-A gene in hematopoietic stem cells causes paroxysmal nocturnal hemoglobinuria. The ISBT database lists one nonsense and three missense germline variants that are associated with the CD59-null phenotype. To analyze the genetic diversity of the CD59 gene, we determined long-range CD59 haplotypes among individuals from different ethnicities. METHODS: We determined a 22.7 kb genomic fragment of the CD59 gene in 113 individuals using next-generation sequencing (NGS), which covered the whole NM_203330.2 mRNA transcript of 7796 base pairs. Samples came from an FDA reference repository and our Ethiopia study cohorts. The raw genotype data were computationally phased into individual haplotype sequences. RESULTS: Nucleotide sequencing of the CD59 gene of 226 chromosomes identified 216 positions with single nucleotide variants. Only three haplotypes were observed in homozygous form, which allowed us to assign them unambiguously as experimentally verified CD59 haplotypes. They were also the most frequent haplotypes among both cohorts. An additional 140 haplotypes were imputed computationally. DISCUSSION: We provided a large set of haplotypes and proposed three verified long-range CD59 reference sequences, based on a population approach, using a generalizable rationale for our choice. Correct long-range haplotypes are useful as template sequences for allele calling in high-throughput NGS and precision medicine approaches, thus enhancing the reliability of clinical diagnostics. Long-range haplotypes can also be used to evaluate the influence of genetic variation on the risk of transfusion reactions or diseases.
Assuntos
Antígenos CD59 , Haplótipos , Humanos , Antígenos CD59/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Etnicidade/genética , Masculino , Feminino , Polimorfismo de Nucleotídeo Único , Anemia Hemolítica , HemoglobinúriaRESUMO
BACKGROUND: N-(-9 acridinyl)-b-alanine hydrochloride (S-300) is the main byproduct of red blood cell (RBC) amustaline/glutathione(GSH) pathogen reduction, currently undergoing phase III US clinical trials following successful European studies(1-3). Phosphatidylinositol glycan, class A (Pig-a) X-linked gene mutagenesis is a validated mammalian in vivo mutation assay for genotoxicity, assessed as clonal loss of glycosylphosphatidylinositol-linked CD59 cell-surface molecules on reticulocytes (RETs) and RBCs. METHODS: Male Sprague-Dawley rats received continuous infusion of S-300 up to the maximum feasible dose (240 mg/kg/day-limited by solubility and volume) for 28 days. Positive controls received a known mutagen by oral gavage on Days 1-3. Plasma levels of S-300 were assessed by HPLC before, during and after infusion. CD59-negative RBCs and RETs were enumerated in pre-dose and Day 28 samples, using a flow cytometric method. Outcome was evaluated by predetermined criteria using concurrent and historical controls. Toxicity was assessed by laboratory measures and necropsy. RESULTS: S-300 reached maximum, dose-dependent levels (3-15 µmol/L) within 2-8 h that were sustained for 672 h and undetectable 2 h after infusion. Circulating RET levels indicated a lack of hematopoietic toxicity. Necropsy revealed minimal-mild observations related to poor S-300 solubility at high concentrations. Pig-a assessment met the preset acceptability criteria and revealed no increase in mutant RBCs or RETs. CONCLUSIONS: Maximum feasible S-300 exposure of rats by continuous infusion for 28 days was not genotoxic as assessed by an Organization for Economic Cooperation and Development-compliant, mammalian, in vivo Pig-a gene mutation assay that meets the requirements of International Conference on Harmonization (ICH) S2(R1) and FDA guidances on genotoxicity testing.
Assuntos
Testes de Mutagenicidade , Ratos Sprague-Dawley , Animais , Masculino , Ratos , Testes de Mutagenicidade/métodos , Antígenos CD59/genética , Reticulócitos/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Proteínas de Membrana/genética , Mutagênese/efeitos dos fármacos , Mutagênicos/toxicidadeRESUMO
BACKGROUND AND AIMS: To further substantiate the role of antibody-mediated complement activation in multifocal motor neuropathy (MMN) immunopathology, we investigated the distribution of promotor polymorphisms of genes encoding the membrane-bound complement regulators CD46, CD55, and CD59 in patients with MMN and controls, and evaluated their association with disease course. METHODS: We used Sanger sequencing to genotype five common polymorphisms in the promotor regions of CD46, CD55, and CD59 in 133 patients with MMN and 380 controls. We correlated each polymorphism to clinical parameters. RESULTS: The genotype frequencies of rs28371582, a 21-bp deletion in the CD55 promotor region, were altered in patients with MMN as compared to controls (p .009; Del/Del genotype 16.8% vs. 7.7%, p .005, odds ratio: 2.43 [1.27-4.58]), and patients carrying this deletion had a more favorable disease course (mean difference 0.26 Medical Research Council [MRC] points/year; 95% confidence interval [CI]: 0.040-0.490, p .019). The presence of CD59 rs141385724 was associated with less severe pre-diagnostic disease course (mean difference 0.940 MRC point/year; 95% CI: 0.083-1.80, p .032). INTERPRETATION: MMN susceptibility is associated with a 21-bp deletion in the CD55 promotor region (rs2871582), which is associated with lower CD55 expression. Patients carrying this deletion may have a more favorable long-term disease outcome. Taken together, these results point out the relevance of the pre-C5 level of the complement cascade in the inflammatory processes underlying MMN.
Assuntos
Antígenos CD55 , Regiões Promotoras Genéticas , Humanos , Antígenos CD55/genética , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Proteína Cofatora de Membrana/genética , Antígenos CD59/genética , Deleção de Sequência , Polineuropatias/genética , Polineuropatias/fisiopatologia , Polineuropatias/imunologia , Progressão da Doença , GenótipoRESUMO
In the aftermath of the COVID-19 pandemic, the evolution of the SARS-CoV-2 into a seasonal pathogen along with the emergence of new variants, underscores the need for dynamic and adaptable responses, emphasizing the importance of sustained vaccination strategies. This observer-blind, double-dummy, randomized immunobridging phase 2 study (NCT05175742) aimed to compare the immunogenicity induced by two doses of 40 µg PTX-COVID19-B vaccine candidate administered 28 days apart, with the response induced by two doses of 30 µg Pfizer-BioNTech COVID-19 vaccine (BNT162b2), administered 21 days apart, in Nucleocapsid-protein seronegative adults 18-64 years of age. Both vaccines were administrated via intramuscular injection in the deltoid muscle. Two weeks after the second dose, the neutralizing antibody (NAb) geometric mean titer ratio and seroconversion rate met the non-inferiority criteria, successfully achieving the primary immunogenicity endpoints of the study. PTX-COVID19-B demonstrated similar safety and tolerability profile to BNT162b2 vaccine. The lowest NAb response was observed in subjects with low-to-undetectable NAb at baseline or no reported breakthrough infection. Conversely, participants who experienced breakthrough infections during the study exhibited higher NAb titers. This study also shows induction of cell-mediated immune (CMI) responses by PTX-COVID19-B. In conclusion, the vaccine candidate PTX-COVID19-B demonstrated favourable safety profile along with immunogenicity similar to the active comparator BNT162b2 vaccine.
Assuntos
Vacinas contra COVID-19 , COVID-19 , Adulto , Humanos , Anticorpos Neutralizantes , Vacina BNT162 , Antígenos CD59 , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Vacinas de mRNA , Pandemias , SARS-CoV-2RESUMO
Multiple myeloma (MM) is an incurable malignancy of the B-cell lineage. Remarkable progress has been made in the treatment of MM with anti-CD38 monoclonal antibodies such as daratumumab and isatuximab, which can kill MM cells by inducing complement-dependent cytotoxicity (CDC). We showed that the CDC efficacy of daratumumab and isatuximab is limited by membrane complement inhibitors, including CD46 and CD59, which are upregulated in MM cells. We recently developed a small recombinant protein, Ad35K++, which is capable of transiently removing CD46 from the cell surface. We also produced a peptide inhibitor of CD59 (rILYd4). In this study, we tested Ad35K++ and rILYd4 in combination with daratumumab and isatuximab in MM cells as well as in cells from two other B-cell malignancies. We showed that Ad35K++ and rILYd4 increased CDC triggered by daratumumab and isatuximab. The combination of both inhibitors had an additive effect in vitro in primary MM cells as well as in vivo in a mouse xenograft model of MM. Daratumumab and isatuximab treatment of MM lines (without Ad35K++ or rILYd4) resulted in the upregulation of CD46/CD59 and/or survival of CD46high/CD59high MM cells that escaped the second round of daratumumab and isatuximab treatment. The escape in the second treatment cycle was prevented by the pretreatment of cells with Ad35K++. Overall, our data demonstrate that Ad35K++ and rILYd4 are efficient co-therapeutics of daratumumab and isatuximab, specifically in multi-cycle treatment regimens, and could be used to improve treatment of multiple myeloma.
Assuntos
Antineoplásicos , Mieloma Múltiplo , Humanos , Camundongos , Animais , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos/uso terapêutico , ADP-Ribosil Ciclase 1/metabolismo , Antígenos CD59/uso terapêutico , Proteína Cofatora de Membrana/metabolismoRESUMO
Evidence for the biosynthetic pathways of the specialized pro-resolving mediator (SPM) protectin D1 (PD1) and its biochemical further local metabolism were presented during the 8th European Workshop on Lipid Mediators, organized June 29th-July 1st, 2022, in Stockholm, Sweden. Herein, we provide an extended and detailed discussion of these topics. PD1, one of 43 SPMs reported so far, exhibits very potent pro-resolution and anti-inflammatory bioactions. Many research groups worldwide have confirmed these and other interesting bioactions. The protectins constitute, together with the lipoxins, resolvins, and maresins, the four individual SPM families, which have received a great interest in basic biomedical research and drug discovery efforts.
Assuntos
Antígenos CD59 , Lipoxinas , Humanos , Antígenos CD59/metabolismo , Vias Biossintéticas , Anti-Inflamatórios , Eicosanoides/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Inflamação/metabolismo , Mediadores da Inflamação/metabolismoRESUMO
BACKGROUND: Homozygous CD59-deficient patients manifest with recurrent peripheral neuropathy resembling Guillain-Barré syndrome (GBS), hemolytic anemia and recurrent strokes. Variable mutations in CD59 leading to loss of function have been described and, overall, 17/18 of patients with any mutation presented with recurrent GBS. Here we determine the localization and possible role of membrane-bound complement regulators, including CD59, in the peripheral nervous systems (PNS) of mice and humans. METHODS: We examined the localization of membrane-bound complement regulators in the peripheral nerves of healthy humans and a CD59-deficient patient, as well as in wild-type (WT) and CD59a-deficient mice. Cross sections of teased sciatic nerves and myelinating dorsal root ganglia (DRG) neuron/Schwann cell cultures were examined by confocal and electron microscopy. RESULTS: We demonstrate that CD59a-deficient mice display normal peripheral nerve morphology but develop myelin abnormalities in older age. They normally express myelin protein zero (P0), ankyrin G (AnkG), Caspr, dystroglycan, and neurofascin. Immunolabeling of WT nerves using antibodies to CD59 and myelin basic protein (MBP), P0, and AnkG revealed that CD59 was localized along the internode but was absent from the nodes of Ranvier. CD59 was also detected in blood vessels within the nerve. Finally, we show that the nodes of Ranvier lack other complement-membrane regulatory proteins, including CD46, CD55, CD35, and CR1-related gene-y (Crry), rendering this area highly exposed to complement attack. CONCLUSION: The Nodes of Ranvier lack CD59 and are hence not protected from complement terminal attack. The myelin unit in human PNS is protected by CD59 and CD55, but not by CD46 or CD35. This renders the nodes and myelin in the PNS vulnerable to complement attack and demyelination in autoinflammatory Guillain-Barré syndrome, as seen in CD59 deficiency.
Assuntos
Síndrome de Guillain-Barré , Proteínas de Membrana , Camundongos , Humanos , Animais , Nós Neurofibrosos , Proteínas do Sistema Complemento , Antígenos CD59/genética , Antígenos CD55/genéticaRESUMO
Rheumatoid arthritis (RA) is typified by persistent joint inflammation, which leads to the deterioration of bone and cartilage and a reduction in overall quality of life. The global prevalence of pain as a primary symptom in RA is influenced by the interplay between inflammation and its resolution. The identification of a family of lipid mediators known as specialized pro-resolving mediators (SPM)s has contributed to the progress of our comprehension of inflammatory conditions. SPMs have been observed to trigger the process of inflammation resolution, thereby reinstating the homeostasis of the inflammatory response. Autacoids are synthesized through the stereo-selective transformation of essential fatty acids, resulting in molecules dynamically modulated during inflammation and possessing strong immunoregulatory properties. This review delves into the available evidence that supports the involvement of certain SPM as protective lipids, biomarkers with potential, and therapeutic targets in the context of RA.
Assuntos
Artrite Reumatoide , Ácidos Docosa-Hexaenoicos , Humanos , Antígenos CD59/uso terapêutico , Qualidade de Vida , Mediadores da Inflamação , Inflamação/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêuticoRESUMO
BACKGROUND: Pregnancy is a physiological state during which inflammation occurs. This complex biological response is necessary for the implantation process as well as delivery. In turn, its suppression during gestation favors the normal course of the pregnancy. Therefore, the presence of pro-resolving mediators, EPA and DHA derivatives, The aim of this study was to investigate the changes in the levels of anti-inflammatory resolvins and their precursors in different trimesters of pregnancy with consideration of the women's weight, including overweight and obese women before pregnancy. METHODS: A total of 78 women participated in this study; the mean age and BMI before pregnancy were 32.3 ± 5.52 and 27.73 ± 6.13, respectively. The patients were divided into two groups, considering their BMI before pregnancy. The extraction of eicosanoids was performed by high-performance liquid chromatography. The results obtained were subjected to statistical analysis. The levels of all studied parameters showed statistically significant differences between the study group (SG) and the control group (CG) in the different trimesters of pregnancy. Over the course of pregnancy, the levels of protection (PDX), maresin, resolvins (RvD1, RvE1), and their precursors differed in relation to the trimester of pregnancy and the division into groups considering the correct body weight before pregnancy. RESULTS: Overweight or obese women had significantly lower levels of RvE1 in the third trimester and their precursors compared to normal-weight women. While the levels of PDX and RvD1 were significantly higher, this may be due to both a lower intake of products rich in omega-3 fatty acids by obese women and an increased need of obese women's bodies to quench chronic inflammatory processes associated with obesity. CONCLUSIONS: Both EPA and DHA derivatives are involved in calming down inflammation during pregnancy, which was observed.
Assuntos
Ácidos Graxos Ômega-3 , Gravidez , Humanos , Feminino , Terceiro Trimestre da Gravidez , Antígenos CD59 , Sobrepeso , Ácidos Docosa-Hexaenoicos , Ácido Eicosapentaenoico , Inflamação/prevenção & controle , ObesidadeRESUMO
Cholesterol-dependent cytolysins (CDCs) are a large family of pore-forming toxins, produced by numerous Gram-positive pathogens. CDCs depend on host membrane cholesterol for pore formation; some CDCs also require surface-associated human CD59 (hCD59) for binding, conferring specificity for human cells. We purified a recombinant version of a putative CDC encoded in the genome of Streptococcus oralis subsp. tigurinus, tigurilysin (TGY), and used CRISPR/Cas9 to construct hCD59 knockout (KO) HeLa and JEG-3 cell lines. Cell viability assays with TGY on wild-type and hCD59 KO cells showed that TGY is a hCD59-dependent CDC. Two variants of TGY exist among S. oralis subsp. tigurinus genomes, only one of which is functional. We discovered that a single amino acid change between these two TGY variants determines its activity. Flow cytometry and oligomerization Western blots revealed that the single amino acid difference between the two TGY isoforms disrupts host cell binding and oligomerization. Furthermore, experiments with hCD59 KO cells and cholesterol-depleted cells demonstrated that TGY is fully dependent on both hCD59 and cholesterol for activity, unlike other known hCD59-dependent CDCs. Using full-length CDCs and toxin constructs differing only in the binding domain, we determined that having hCD59 dependence leads to increased lysis efficiency, conferring a potential advantage to organisms producing hCD59-dependent CDCs.
Assuntos
Citotoxinas , Especificidade de Hospedeiro , Humanos , Linhagem Celular Tumoral , Citotoxinas/genética , Colesterol , Aminoácidos , Antígenos CD59/genéticaRESUMO
BACKGROUND: Cell surface molecules play important roles in cell signal transduction pathways during microbial infection. OBJECTIVE: In this study, the expression and the functions of CD59 was investigated in H. pylori infected gastric cancer (GC). METHODS AND RESULTS: The differential expression of CD59 and the influence of H. pylori on the expression of CD59 were analyzed via bioinformatics through Gene Set Enrichment in GC. In addition, the expression of CD59 in GES-1, AGS cells and GC tissues infected with H. pylori was confirmed by Western blot. Bioinformatics results and H. pylori infection experiments showed CD59 decreased obviously in H. pylori infected GC cells and tissues. The expression of CD59 was linked to the survival rate of GC patients, and influenced various immune cells in the immune microenvironment of GC. CD59 interacts with other genes to form a network in H. pylori infected GC. Certainly, CD59 decreased significantly in H. pylori infected GC tissues, GES-1 and AGS cells in vitro. CONCLUSION: H. pylori infection could influence the expression of CD59 in GC indicating that CD59 may be a promising treatment target.
Assuntos
Helicobacter pylori , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Helicobacter pylori/genética , Biologia Computacional , Transdução de Sinais , Microambiente Tumoral , Antígenos CD59/genéticaRESUMO
CD59 is a GPI-anchored cell surface receptor that serves as a gatekeeper to controlling pore formation. It is the only membrane-bound inhibitor of the complement membrane attack complex (MAC), an immune pore that can damage human cells. While CD59 blocks MAC pores, the receptor is co-opted by bacterial pore-forming proteins to target human cells. Recent structures of CD59 in complexes with binding partners showed dramatic differences in the orientation of its ectodomain relative to the membrane. Here, we show how GPI-anchored CD59 can satisfy this diversity in binding modes. We present a PyLipID analysis of coarse-grain molecular dynamics simulations of a CD59-inhibited MAC to reveal residues of complement proteins (C6:Y285, C6:R407 C6:K412, C7:F224, C8ß:F202, C8ß:K326) that likely interact with lipids. Using modules of the MDAnalysis package to investigate atomistic simulations of GPI-anchored CD59, we discover properties of CD59 that encode the flexibility necessary to bind both complement proteins and bacterial virulence factors.
Assuntos
Complexo de Ataque à Membrana do Sistema Complemento , Proteínas do Sistema Complemento , Humanos , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Antígenos CD59/química , Antígenos CD59/metabolismo , Bactérias/metabolismoRESUMO
CD59 is an abundant immuno-regulatory human protein that protects cells from damage by inhibiting the complement system. CD59 inhibits the assembly of the Membrane Attack Complex (MAC), the bactericidal pore-forming toxin of the innate immune system. In addition, several pathogenic viruses, including HIV-1, escape complement-mediated virolysis by incorporating this complement inhibitor in their own viral envelope. This makes human pathogenic viruses, such as HIV-1, not neutralised by the complement in human fluids. CD59 is also overexpressed in several cancer cells to resist the complement attack. Consistent with its importance as a therapeutical target, CD59-targeting antibodies have been proven to be successful in hindering HIV-1 growth and counteracting the effect of complement inhibition by specific cancer cells. In this work, we make use of bioinformatics and computational tools to identify CD59 interactions with blocking antibodies and to describe molecular details of the paratope-epitope interface. Based on this information, we design and produce paratope-mimicking bicyclic peptides able to target CD59. Our results set the basis for the development of antibody-mimicking small molecules targeting CD59 with potential therapeutic interest as complement activators.
Assuntos
Proteínas do Sistema Complemento , HIV-1 , Humanos , Sítios de Ligação de Anticorpos , Proteínas do Sistema Complemento/metabolismo , Antígenos CD59/metabolismo , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Inativadores do Complemento , HIV-1/fisiologiaRESUMO
AIMS: Gestational diabetes (GDM) is associated with the development of postpartum (PP) glucose intolerance. Plasma glycated CD59 (pGCD59) is an emerging biomarker for the detection of hyperglycaemia. The aim of this study was to assess the ability of PP pGCD59 to predict the development of PP GI as defined by the 2 h 75 g OGTT using the ADA criteria, in a cohort of women diagnosed with prior GDM in the index pregnancy using the 2 h 75 g OGTT at 24-28 weeks of gestation according to the World Health Organization (WHO) 2013 criteria. METHODS: Of the 2017 pregnant women recruited prospectively 140 women with gestational diabetes had samples for pGCD59 taken PP at the time of the OGTT. The ability of pGCD59 to predict the results of the PP OGTT was assessed using nonparametric receiver operating characteristic (ROC) curves. RESULTS: Women with PP glucose intolerance had significantly higher PP pGCD59 levels compared to women with normal glucose tolerance PP (3.8 vs. 2.7 SPU). PP pGCD59 identified women who developed glucose intolerance PP with an AUC of 0.80 (95% CI: 0.70-0.91). A PP pGCD59 cut-off value of 1.9 SPU generated a sensitivity of 100% (95% CI: 83.9-100), specificity of 16.9% (95% CI: 9.8-26.3), positive predictive value of 22.1% (95% CI: 21.0-22.6), and negative predictive value of 100% (95% CI: 87.4-100). PP fasting plasma glucose generated an AUC of 0.96 (95% CI: 0.89-0.99) for the identification of PP glucose intolerance. CONCLUSION: Our study found that PP pGCD9 may be a promising biomarker to identify women not requiring PP glucose intolerance screening using the traditional OGTT. While the diagnostic accuracy of pGCD59 is good, fasting plasma glucose remains a better test for the identification of PP glucose intolerance.
Assuntos
Diabetes Gestacional , Intolerância à Glucose , Feminino , Gravidez , Humanos , Diabetes Gestacional/diagnóstico , Intolerância à Glucose/diagnóstico , Intolerância à Glucose/epidemiologia , Estudos Prospectivos , Glicemia , Teste de Tolerância a Glucose , Estudos Retrospectivos , Período Pós-Parto , Biomarcadores , Antígenos CD59RESUMO
BACKGROUND: Acute lung injury (ALI) is a common and serious complication of sepsis with high mortality. Ferroptosis, categorized as programmed cell death, contributes to the development of lung injury. Protectin conjugates in tissue regeneration 1 (PCTR1) is an endogenous lipid mediator that exerts protective effects against multiorgan injury. However, the role of PCTR1 in the ferroptosis of sepsis-related ALI remains unknown. METHODS: A pulmonary epithelial cell line and a mouse model of ALI stimulated with lipopolysaccharide (LPS) were established in vitro and in vivo. Ferroptosis biomarkers, including ferrous (Fe2+), glutathione (GSH), malondialdehyde (MDA) and 4-Hydroxynonenal (4-HNE), were assessed by relevant assay kits. Glutathione peroxidase 4 (GPX4) and prostaglandin-endoperoxide synthase 2 (PTGS2) protein levels were determined by western blotting. Lipid peroxides were examined by fluorescence microscopy and flow cytometry. Cell viability was determined by a CCK-8 assay kit. The ultrastructure of mitochondria was observed with transmission electron microscopy. Morphology and inflammatory cytokine levels predicted the severity of lung injury. Afterward, related inhibitors were used to explore the potential mechanism by which PCTR1 regulates ferroptosis. RESULTS: PCTR1 treatment protected mice from LPS-induced lung injury, which was consistent with the effect of the ferroptosis inhibitor ferrostatin-1. PCTR1 treatment decreased Fe2+, PTGS2 and lipid reactive oxygen species (ROS) contents, increased GSH and GPX4 levels and ameliorated mitochondrial ultrastructural injury. Administration of LPS or the ferroptosis agonist RSL3 resulted in reduced cell viability, which was rescued by PCTR1. Mechanistically, inhibition of the PCTR1 receptor lipoxin A4 (ALX), protein kinase A (PKA) and transcription factor cAMP-response element binding protein (CREB) partly decreased PCTR1 upregulated GPX4 expression and a CREB inhibitor blocked the effects ofPCTR1 on ferroptosis inhibition and lung protection. CONCLUSION: This study suggests that PCTR1 suppresses LPS-induced ferroptosis via the ALX/PKA/CREB signaling pathway, which may offer promising therapeutic prospects in sepsis-related ALI.
Assuntos
Lesão Pulmonar Aguda , Ferroptose , Sepse , Animais , Camundongos , Antígenos CD59 , Ciclo-Oxigenase 2 , Lipopolissacarídeos/farmacologia , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/etiologia , Sepse/complicações , Fator 2 Ativador da TranscriçãoRESUMO
Methods: A case-control study was conducted to investigate the SNPs at CD59 rs1047581, rs7046, rs2231460, rs184251026, rs41275164, rs831633, rs704700, rs41275166, and rs10768024 by sequence-specific primer-polymerase chain reaction (SSP-PCR) in 900 tuberculosis patients and 1,534 controls. Results: The minor allele frequencies at rs2231460, rs184251026, rs41275164, and rs41275166 were extremely low both in the Cases (0.00%-0.61%) and in the Controls (0.07%-0.43%), comparatively at rs1047581, rs7046, rs831633, rs704700, and rs10768024 were notably higher both in the Cases (8.23%-48.39%) and in the Controls (8.57%-47.16%). Among the nine SNPs, only homozygous CC genotype at rs10768024 showed a significant protective effect against TB than homozygous TT genotype (OR(95% CI) = 0.59(0.38, 0.91), χ 2 = 5.779, P = 0.016), and homozygous TT and heterozygous CT genotypes showed a significant risk of TB infection in the recessive model (OR(95% CI) = 1.68(1.10, 2.56), χ 2 = 5.769, P = 0.016). Further analysis verified that rs10768024 CC genotype independently related to TB susceptibility (OR(95% CI) = 0.60(0.39, 0.91), Wald χ 2 = 5.664, P = 0.017) in multivariate logistic regression analysis, and its genetic mutation was independent of the other SNPs (r 2 = 0.00-0.20) in haplotype analysis. Conclusions: The first investigation of the CD59 gene and susceptibility to TB suggests a significant risk with homozygous TT and heterozygous CT genotypes at rs10768024 loci. The homozygous CC mutation at rs10768024 loci showed a significant protection against TB susceptibility.
Assuntos
Antígenos CD59 , População do Leste Asiático , Predisposição Genética para Doença , Mycobacterium tuberculosis , Tuberculose , Humanos , Estudos de Casos e Controles , Antígenos CD59/genética , China/epidemiologia , População do Leste Asiático/genética , População do Leste Asiático/estatística & dados numéricos , Frequência do Gene , Predisposição Genética para Doença/genética , Genótipo , Mutação , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Tuberculose/epidemiologia , Tuberculose/genéticaRESUMO
OBJECTIVES: To describe the clinical phenotype of eight children diagnosed with CD59 deficiency and their ultimate neurological outcome. METHODS: The data of our cases were extensively reviewed both clinical and ancillary tests; investigations included: neuroimaging, neurophysiological studies, and laboratory tests. RESULTS: All patients presented during early infancy with Guillain-Barre syndrome later they suffered repeated relapses leading to the diagnosis of chronic axonal neuropathy. Recurrent stroke and acute necrotizing encephalopathy were described, 2 patients in each group. One girl developed acute disseminated encephalomyelitis while one boy developed acute transverse myelitis. Overt hemolytic anemia requiring blood transfusion reported in six patients. CONCLUSION: Inherited CD59 deficiency is an autosomal recessive disorder which can have devastating neurological consequences. First line immunotherapy including intravenous immunoglobin, corticosteroids, and plasma exchange may have transient beneficial effect. Reports of targeted therapy with eculizumab might be lifesaving. Genetic counseling is crucial.