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2.
Skin Res Technol ; 29(12): e13493, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38017667

RESUMO

BACKGROUND: Photodynamic therapy (PDT) is an effective treatment for actinic keratosis (AKs), but there is little information on how PDT affects skin barrier function. The objectives of this study are: To compare skin barrier function between skin with AKs and healthy skin and to evaluate the impact of PDT on skin homeostasis in patients with AKs. METHODS: A prospective observational study was conducted in patients with AKs to evaluate epidermal barrier function and skin homeostasis before and 1 ek after receiving PDT. RESULTS: A total of 21 subjects were included in the study, male/female ratio was 17:4, mean age was 75.86 years. The number of AKS observed before starting treatment was reduced with respect to those diagnosed 1 month after starting PDT (14.83 vs. 1.91, p < 0.0001). Application of PDT for treating AKs modifies epidermal barrier function. Immediately after the first session temperature, transepidermal water loss (TEWL), stratum corneum hydration (SCH) and total antioxidant capacity (TAC) increased while pH decreased on lesional skin. After 1-month follow-up, the only remained change was the increased in SCH. Higher increases in temperature were observed when using occlusive PDT compared to mixed modality. 5-ALA and M-ALA seem to have a similar impact on skin barrier. CONCLUSIONS: PDT can improve skin barrier function in patients with AKs. Skin homeostasis parameters can be used to assess efficacy and optimize dosing.


Assuntos
Ceratose Actínica , Fotoquimioterapia , Dermatoses do Couro Cabeludo , Idoso , Feminino , Humanos , Masculino , Ácido Aminolevulínico/uso terapêutico , Ácido Aminolevulínico/efeitos adversos , Ceratose Actínica/tratamento farmacológico , Fotoquimioterapia/efeitos adversos , Fármacos Fotossensibilizantes , Resultado do Tratamento , Estudos Prospectivos
3.
Res Sq ; 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37790523

RESUMO

We characterized virus-neutralization and spike-binding antibody profiles in myeloma patients following monovalent or bivalent-SARS-CoV-2 booster vaccination. Vaccination improves the breadth of binding antibodies but not neutralization activity against current variants. Hybrid immunity and immune imprinting impact vaccine-elicited immunity.

4.
bioRxiv ; 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37662390

RESUMO

We characterized virus-neutralization and spike-binding antibody profiles in myeloma patients following monovalent or bivalent-SARS-CoV-2 booster vaccination. Vaccination improves the breadth of binding antibodies but not neutralization activity against current variants. Hybrid immunity and immune imprinting impact vaccine-elicited immunity.

5.
J Thorac Oncol ; 18(11): 1504-1523, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37437883

RESUMO

INTRODUCTION: Lung cancer remains the deadliest cancer in the world, and lung cancer survival is heavily dependent on tumor stage at the time of detection. Low-dose computed tomography screening can reduce mortality; however, annual screening is limited by low adherence in the United States of America and still not broadly implemented in Europe. As a result, less than 10% of lung cancers are detected through existing programs. Thus, there is a great need for additional screening tests, such as a blood test, that could be deployed in the primary care setting. METHODS: We prospectively recruited 1384 individuals meeting the National Lung Screening Trial demographic eligibility criteria for lung cancer and collected stabilized whole blood to enable the pipetting-free collection of material, thus minimizing preanalytical noise. Ultra-deep small RNA sequencing (20 million reads per sample) was performed with the addition of a method to remove highly abundant erythroid RNAs, and thus open bandwidth for the detection of less abundant species originating from the plasma or the immune cellular compartment. We used 100 random data splits to train and evaluate an ensemble of logistic regression classifiers using small RNA expression of 943 individuals, discovered an 18-small RNA feature consensus signature (miLung), and validated this signature in an independent cohort (441 individuals). Blood cell sorting and tumor tissue sequencing were performed to deconvolve small RNAs into their source of origin. RESULTS: We generated diagnostic models and report a median receiver-operating characteristic area under the curve of 0.86 (95% confidence interval [CI]: 0.84-0.86) in the discovery cohort and generalized performance of 0.83 in the validation cohort. Diagnostic performance increased in a stage-dependent manner ranging from 0.73 (95% CI: 0.71-0.76) for stage I to 0.90 (95% CI: 0.89-0.90) for stage IV in the discovery cohort and from 0.76 to 0.86 in the validation cohort. We identified a tumor-shed, plasma-bound ribosomal RNA fragment of the L1 stalk as a dominant predictor of lung cancer. The fragment is decreased after surgery with curative intent. In additional experiments, results of dried blood spot collection and sequencing revealed that small RNA analysis could potentially be conducted through home sampling. CONCLUSIONS: These data suggest the potential of a small RNA-based blood test as a viable alternative to low-dose computed tomography screening for early detection of smoking-associated lung cancer.


Assuntos
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Detecção Precoce de Câncer/métodos , Pulmão/patologia , Fumar , RNA
7.
CRISPR J ; 6(1): 5-16, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36662546

RESUMO

Cellular therapies hold enormous potential for the cure of severe hematological and oncological disorders. The forefront of innovative gene therapy approaches including therapeutic gene editing and hematopoietic stem cell transplantation needs to be processed by good manufacturing practice to ensure safe application in patients. In the present study, an effective transfection protocol for automated clinical-scale production of genetically modified hematopoietic stem and progenitor cells (HSPCs) using the CliniMACS Prodigy® system including the CliniMACS Electroporator (Miltenyi Biotec) was established. As a proof-of-concept, the enhancer of the BCL11A gene, clustered regularly interspaced short palindromic repeat (CRISPR) target in ongoing clinical trials for ß-thalassemia and sickle-cell disease treatment, was disrupted by the CRISPR-Cas9 system simulating a large-scale clinical scenario, yielding 100 million HSPCs with high editing efficiency. In vitro erythroid differentiation and high-performance liquid chromatography analyses corroborated fetal hemoglobin resurgence in edited samples, supporting the feasibility of running the complete process of HSPC gene editing in an automated closed system.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Hemoglobinopatias , Humanos , Edição de Genes/métodos , Sistemas CRISPR-Cas/genética , Hemoglobinopatias/genética , Hemoglobinopatias/terapia , Células-Tronco Hematopoéticas
8.
Blood Cancer Discov ; 4(2): 106-117, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36511813

RESUMO

Patients with multiple myeloma (MM) mount suboptimal neutralizing antibodies (nAb) following 2 doses of SARS-CoV-2 mRNA vaccines. Currently, circulating SARS-CoV-2 variants of concern (VOC) carry the risk of breakthrough infections. We evaluated immune recognition of current VOC including BA.1, BA.2, and BA.5 in 331 racially representative patients with MM following 2 or 3 doses of mRNA vaccines. The third dose increased nAbs against WA1 in 82%, but against BA variants in only 33% to 44% of patients. Vaccine-induced nAbs correlated with receptor-binding domain (RBD)-specific class-switched memory B cells. Vaccine-induced spike-specific T cells were detected in patients without seroconversion and cross-recognized variant-specific peptides but were predominantly CD4+ T cells. Detailed clinical/immunophenotypic analysis identified features correlating with nAb/B/T-cell responses. Patients who developed breakthrough infections following 3 vaccine doses had lower live-virus nAbs, including against VOC. Patients with MM remain susceptible to SARS-CoV-2 variants following 3 vaccine doses and should be prioritized for emerging approaches to elicit variant-nAb and CD8+ T cells. SIGNIFICANCE: Three doses of SARS-CoV-2 mRNA vaccines fail to yield detectable VOC nAbs in nearly 60% and spike-specific CD8+ T cells in >80% of myeloma patients. Patients who develop breakthrough infections following vaccination have low levels of live-virus nAb. This article is highlighted in the In This Issue feature, p. 101.


Assuntos
COVID-19 , Mieloma Múltiplo , Humanos , SARS-CoV-2 , Infecções Irruptivas , COVID-19/prevenção & controle , Linfócitos T CD8-Positivos , Vacinas de mRNA , Anticorpos Neutralizantes
9.
Drug Alcohol Depend ; 242: 109714, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36463764

RESUMO

BACKGROUND: This systematic review summarized published literature on county-level predictors of drug overdose mortality in the United States (US). METHODS: Peer-reviewed studies and doctoral dissertations published in English between 1990 and July 19, 2022 were identified from PubMed, Web of Science, ProQuest Dissertations & Theses, PsycINFO, CINAHL, and EconLit. Eligible studies examined at least one county-level predictor of drug overdose mortality in US counties. Two reviewers independently completed screening, quality assessment (with an adapted National Institutes of Health Quality Assessment Tool), and data extraction. Results were qualitatively summarized and grouped by predictor categories. RESULTS: Of 56 studies included, 42.9% were subnational, and 53.6% were limited to opioid overdose. In multiple studies, measures related to opioid prescribing, illness/disability, economic distress, mining employment, incarceration, family distress, and single-parent families were positively associated with drug overdose mortality outcomes, while measures related to cannabis dispensaries, substance use treatment, social capital, and family households were negatively associated with drug overdose mortality outcomes. Both positive and negative associations were documented for smoking, uninsurance, healthcare professional shortage status, physicians per capita, unemployment, income, poverty, educational attainment, racial composition, and rurality. Findings within studies also differed by subpopulation (by race/ethnicity, gender, age, or rurality) and the type of drugs involved in overdose. CONCLUSIONS: The findings of this review provide relatively mixed evidence regarding many county-level predictors of overdose mortality, several of which also vary between subpopulations, supporting the importance of additional research to elucidate pathways through which the county context may shape risk of fatal overdose.


Assuntos
Overdose de Drogas , Transtornos Relacionados ao Uso de Substâncias , Humanos , Estados Unidos , Analgésicos Opioides , Padrões de Prática Médica , Etnicidade
10.
NPJ Precis Oncol ; 6(1): 19, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35361874

RESUMO

Immunotherapies have recently gained traction as highly effective therapies in a subset of late-stage cancers. Unfortunately, only a minority of patients experience the remarkable benefits of immunotherapies, whilst others fail to respond or even come to harm through immune-related adverse events. For immunotherapies within the PD-1/PD-L1 inhibitor class, patient stratification is currently performed using tumor (tissue-based) PD-L1 expression. However, PD-L1 is an accurate predictor of response in only ~30% of cases. There is pressing need for more accurate biomarkers for immunotherapy response prediction. We sought to identify peripheral blood biomarkers, predictive of response to immunotherapies against lung cancer, based on whole blood microRNA profiling. Using three well-characterized cohorts consisting of a total of 334 stage IV NSCLC patients, we have defined a 5 microRNA risk score (miRisk) that is predictive of overall survival following immunotherapy in training and independent validation (HR 2.40, 95% CI 1.37-4.19; P < 0.01) cohorts. We have traced the signature to a myeloid origin and performed miRNA target prediction to make a direct mechanistic link to the PD-L1 signaling pathway and PD-L1 itself. The miRisk score offers a potential blood-based companion diagnostic for immunotherapy that outperforms tissue-based PD-L1 staining.

11.
CRISPR J ; 5(1): 66-79, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34882002

RESUMO

Metachromatic leukodystrophy (MLD) is a rare genetic disorder caused by mutations in the Arylsulfatase-A (ARSA) gene. The enzyme plays a key role in sulfatide metabolism in brain cells, and its deficiency leads to neurodegeneration. The clinical manifestations of MLD include stagnation and decline of motor and cognitive function, leading to premature death with limited standard treatment options. Here, we describe a mutation-agnostic hematopoietic stem and progenitor cell (HSPC) gene therapy using CRISPR-Cas9 and AAV6 repair template as a prospective treatment option for MLD. Our strategy achieved efficient insertions and deletions (>87%) and a high level of gene integration (>47%) at the ARSA locus in human bone marrow-derived HSPCs, with no detectable off-target editing. As a proof of concept, we tested our mutation-agnostic therapy in HSPCs derived from two MLD patients with distinct mutations and demonstrated restoration of ARSA enzyme activity (>30-fold improvement) equivalent to healthy adults. In summary, our investigation enabled a mutation-agnostic therapy for MLD patients with proven efficacy and strong potential for clinical translation.


Assuntos
Leucodistrofia Metacromática , Sistemas CRISPR-Cas/genética , Edição de Genes , Terapia Genética , Células-Tronco Hematopoéticas/metabolismo , Humanos , Leucodistrofia Metacromática/genética , Leucodistrofia Metacromática/terapia , Mutação , Estudos Prospectivos
12.
CRISPR J ; 4(2): 207-222, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33876951

RESUMO

Mutations in the human ß-globin gene are the cause of ß-hemoglobinopathies, one of the most common inherited single-gene blood disorders in the world. Novel therapeutic approaches are based on lentiviral vectors (LVs) or CRISPR-Cas9-mediated gene disruption to express adult hemoglobin (HbA), or to reactivate the completely functional fetal hemoglobin, respectively. Nonetheless, LVs present a risk of insertional mutagenesis, while gene-disrupting transcription factors (BCL11A, KLF1) involved in the fetal-to-adult hemoglobin switch might generate dysregulation of other cellular processes. Therefore, universal gene addition/correction approaches combining CRISPR-Cas9 and homology directed repair (HDR) by delivering a DNA repair template through adeno-associated virus could mitigate the limitations of both lentiviral gene transfer and gene disruption strategies, ensuring targeted integration and controlled transgene expression. In this study, we attained high rates of gene addition (up to 12%) and gene correction (up to 38%) in hematopoietic stem and progenitor cells from healthy donors without any cell sorting/enrichment or the application of HDR enhancers. Furthermore, these approaches were tested in heterozygous (ß0/ß+) and homozygous (ß0/ß0, ß+/ß+) ß-thalassemia patients, achieving a significant increase in HbA and demonstrating the universal therapeutic potential of this study for the treatment of ß-hemoglobinopathies.


Assuntos
Sistemas CRISPR-Cas , Dependovirus/genética , Terapia Genética , Hemoglobinopatias/genética , Hemoglobinopatias/terapia , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Dependovirus/metabolismo , Hemoglobina Fetal/genética , Hemoglobina Fetal/metabolismo , Edição de Genes , Células-Tronco Hematopoéticas , Humanos , Globinas beta/genética , Globinas beta/metabolismo , Talassemia beta/genética , Talassemia beta/metabolismo , Talassemia beta/terapia
13.
Rep Pract Oncol Radiother ; 26(6): 839-848, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34992855

RESUMO

BACKGROUND: A clinical decision support system (CDSS ) has been designed to predict the outcome (overall survival) by extracting and analyzing information from routine clinical activity as a complement to clinical guidelines in lung cancer patients. MATERIALS AND METHODS: Prospective multicenter data from 543 consecutive (2013-2017) lung cancer patients with 1167 variables were used for development of the CDSS. Data Mining analyses were based on the XGBoost and Generalized Linear Models algorithms. The predictions from guidelines and the CDSS proposed were compared. RESULTS: Overall, the highest (> 0.90) areas under the receiver-operating characteristics curve AUCs for predicting survival were obtained for small cell lung cancer patients. The AUCs for predicting survival using basic items included in the guidelines were mostly below 0.70 while those obtained using the CDSS were mostly above 0.70. The vast majority of comparisons between the guideline and CDSS AUCs were statistically significant (p < 0.05). For instance, using the guidelines, the AUC for predicting survival was 0.60 while the predictive power of the CDSS enhanced the AUC up to 0.84 (p = 0.0009). In terms of histology, there was only a statistically significant difference when comparing the AUCs of small cell lung cancer patients (0.96) and all lung cancer patients with longer (≥ 18 months) follow up (0.80; p < 0.001). CONCLUSIONS: The CDSS successfully showed potential for enhancing prediction of survival. The CDSS could assist physicians in formulating evidence-based management advice in patients with lung cancer, guiding an individualized discussion according to prognosis.

14.
Blood Cells Mol Dis ; 84: 102456, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32498026

RESUMO

ß-Hemoglobinopathies are among the most common single-gene disorders and are caused by different mutations in the ß-globin gene. Recent curative therapeutic approaches for these disorders utilize lentiviral vectors (LVs) to introduce a functional copy of the ß-globin gene into the patient's hematopoietic stem cells. Alternatively, fetal hemoglobin (HbF) can reduce or even prevent the symptoms of disease when expressed in adults. Thus, induction of HbF by means of LVs and other molecular approaches has become an alternative treatment of ß-hemoglobinopathies. Here, we performed a head-to-head comparative analysis of HbF-inducing LVs encoding for: 1) IGF2BP1, 2) miRNA-embedded shRNA (shmiR) sequences specific for the γ-globin repressor protein BCL11A, and 3) γ-globin gene. Furthermore, two novel baboon envelope proteins (BaEV)-LVs were compared to the commonly used vesicular-stomatitis-virus glycoprotein (VSV-G)-LVs. Therapeutic levels of HbF were achieved for all VSV-G-LV approaches, from a therapeutic level of 20% using γ-globin LVs to 50% for both IGF2BP1 and BCL11A-shmiR LVs. Contrarily, BaEV-LVs conferred lower HbF expression with a peak level of 13%, however, this could still ameliorate symptoms of disease. From this thorough comparative analysis of independent HbF-inducing LV strategies, we conclude that HbF-inducing VSV-G-LVs represent a promising alternative to ß-globin gene addition for patients with ß-hemoglobinopathies.


Assuntos
Hemoglobina Fetal/genética , Vetores Genéticos/genética , Hemoglobinopatias/terapia , Lentivirus/genética , Linhagem Celular , Células Cultivadas , Expressão Gênica , Técnicas de Transferência de Genes , Terapia Genética , Vetores Genéticos/administração & dosagem , Vetores Genéticos/uso terapêutico , Hemoglobinopatias/genética , Humanos , Transdução Genética , Regulação para Cima , gama-Globinas/genética
15.
Brief Funct Genomics ; 19(3): 191-200, 2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-31844895

RESUMO

Chimeric antigen receptor (CAR)-modified T cells have raised among other immunotherapies for cancer treatment, being implemented against B-cell malignancies. Despite the promising outcomes of this innovative technology, CAR-T cells are not exempt from limitations that must yet to be overcome in order to provide reliable and more efficient treatments against other types of cancer. The purpose of this review is to shed light on the field of CAR-T cell gene editing for therapy universalization and further enhancement of antitumor function. Several studies have proven that the disruption of certain key genes is essential to boost immunosuppressive resistance, prevention of fratricide, and clinical safety. Due to its unparalleled simplicity, feasibility to edit multiple gene targets simultaneously, and affordability, CRISPR/CRISPR-associated protein 9 system has been proposed in different clinical trials for such CAR-T cell improvement. The combination of such powerful technologies is expected to provide a new generation of CAR-T cell-based immunotherapies for clinical application.


Assuntos
Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Imunoterapia/métodos , Humanos
16.
Blood Rev ; 40: 100641, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31761379

RESUMO

Due to pioneering in vitro investigations on gene modification, gene engineering platforms have incredibly improved to a safer and more powerful tool for the treatment of multiple blood and immune disorders. Likewise, several clinical trials have been initiated combining autologous hematopoietic stem cell transplantation (auto-HSCT) with gene therapy (GT) tools. As several GT modalities such as lentivirus and gene editing tools have a long developmental path ahead to diminish its negative side effects, it is hard to decide which modality is optimal for treating a specific disease. Gene transfer by lentiviruses is the platform of choice for loss-of-mutation diseases, whereas gene correction/addition or gene disruption by gene editing tools, mainly CRISPR/Cas9, is likely to be more efficient in diseases where tight regulation is needed. Therefore, in this review, we compiled pertinent information about lentiviral gene transfer and CRISPR/Cas9 gene editing, their evolution to a safer platform for HSCT, and their applications on other types of gene disorders based on the etiology of the disease and cell fitness.


Assuntos
Edição de Genes , Terapia Genética , Doenças Hematológicas , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas , Doenças do Sistema Imunitário , Lentivirus , Autoenxertos , Doenças Hematológicas/genética , Doenças Hematológicas/terapia , Humanos , Doenças do Sistema Imunitário/genética , Doenças do Sistema Imunitário/terapia
17.
Bone Marrow Transplant ; 54(12): 1940-1950, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30903024

RESUMO

Allogeneic hematopoietic stem cell transplantation (HSCT) is a standard therapeutic intervention for hematological malignancies and several monogenic diseases. However, this approach has limitations related to lack of a suitable donor, graft-versus-host disease and infectious complications due to immune suppression. On the contrary, autologous HSCT diminishes the negative effects of allogeneic HSCT. Despite the good efficacy, earlier gene therapy trials with autologous HSCs and viral vectors have raised serious safety concerns. However, the CRISPR/Cas9-edited autologous HSCs have been proposed to be an alternative option with a high safety profile. In this review, we summarized the possibility of CRISPR/Cas9-mediated autologous HSCT as a potential treatment option for various diseases supported by preclinical gene-editing studies. Furthermore, we discussed future clinical perspectives and possible clinical grade improvements of CRISPR/cas9-mediated autologous HSCT.


Assuntos
Sistemas CRISPR-Cas/genética , Transplante de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco/métodos , Condicionamento Pré-Transplante/métodos , Transplante Homólogo/métodos , Humanos
18.
Trauma Surg Acute Care Open ; 4(1): e000227, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30729174

RESUMO

BACKGROUND: The American College of Surgeons Bleeding Control Basic (BCon) course aimed at teaching hemorrhage control techniques in the USA had not yet been taught in Spain. The purpose of this study is to assess its implementation among students and healthcare employees in the Lozano Blesa University Hospital of Zaragoza, a middle-sized Spanish city. METHODS: The study was conducted in a University Hospital and at the University of Zaragoza, scheduling four free B-Con sessions from 2017 to 2018. Two groups were identified as forming the population: healthcare employees and medical students. An anonymous questionnaire was completed at the end of the course regarding content, applicability, usefulness, relevance, and satisfaction. Study variables were ranked from 0 to 10: poor (when graded from 0 to 3), fair (4 to 6) and good (7 to 10). Results were compared between the groups, expressed in percentages and χ2 tested to analyze significant differences if any. RESULTS: Among the 83 individuals who completed the course, 46 were medical students and 37 healthcare employees; 61% women and 39% men; aged 21 years to 52 years. Attendees evaluated satisfaction with the highest grade (84%), followed by usefulness (73%), applicability (70%), and relevance (66%). There was no variable graded as poor. The comparison of perceptions between groups did not reveal statistical differences based on a 0.05 significance level. CONCLUSION: We concluded that the B-Con course was valued as good for relevance, usefulness, applicability, and satisfaction by the majority of the studied population. LEVEL OF EVIDENCE: Level III.

19.
Vaccine ; 37(2): 306-313, 2019 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-30509693

RESUMO

Plasmodium vivax Merozoite Surface Protein-9 (PvMSP-9) is a malaria vaccine candidate naturally immunogenic in humans and able to induce high antibody titers in animals when delivered as a recombinant protein. Recently, we identified the sequence EAAPENAEPVHENA (PvMSP9E795-A808) as the main linear B-cell epitope in naturally exposed individuals. However, the potential of PvMSP9E795-A808 as an immunogen in experimental animal models remained unexplored. Here we assess the immunogenicity of PvMSP9E795-A808 using synthetic peptides. The peptides tested in BALB/c mice include two repeats of the sequence EAAPENAEPVHENA tested alone (peptide RII), or linked to an autologous (PvMSP9 peptide pL; pLRII) or heterologous (p2 tetanus toxin universal T cell epitope; TTRII) T cell epitope. Immune responses were evaluated by ELISA, FLUOROSPOT, and indirect immunofluorescence. We show that all of the peptide constructs tested were immunogenic eliciting specific IgG antibodies at different levels, with a prevalence of IgG1 and IgG2. Animals immunized with synthetic peptides containing T cell epitopes (pLRII or TTRII) had more efficient antibody responses that resulted in higher antibody titers able to recognize the native protein by immunofluorescence. Relevantly, the frequency of IFN-γ secreting SFC elicited by immunization with TTRII synthetic peptide was comparable to that reported to the PvMSP9-Nt recombinant protein. Taken together, our study indicates that PvMSP9E795-A808 is highly immunogenic in mice and further studies to evaluate its value as promising vaccine target are warranted. Moreover, our study supports the critical role of CD4 T cell epitopes to enhance humoral responses induced by subunit based vaccines.


Assuntos
Epitopos de Linfócito B/imunologia , Imunogenicidade da Vacina , Vacinas Antimaláricas/imunologia , Proteínas de Membrana/imunologia , Peptídeos/síntese química , Proteínas de Protozoários/imunologia , Animais , Anticorpos Antiprotozoários/imunologia , Formação de Anticorpos , Ensaio de Imunoadsorção Enzimática , Feminino , Imunoglobulina G/imunologia , Vacinas Antimaláricas/genética , Malária Vivax/prevenção & controle , Proteínas de Membrana/genética , Camundongos Endogâmicos BALB C , Peptídeos/imunologia , Plasmodium vivax , Proteínas de Protozoários/genética , Proteínas Recombinantes/síntese química , Proteínas Recombinantes/imunologia , Vacinas de Subunidades Antigênicas/genética , Vacinas de Subunidades Antigênicas/imunologia
20.
Front Immunol ; 9: 2612, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30473702

RESUMO

The delay in parasite-specific B cell development leaves people in malaria endemic areas vulnerable to repeated Plasmodium infections. Here, we investigated the role of transmembrane activator and calcium-modulator and cyclophilin ligand interactor (TACI), a molecule involved in the generation of antigen-specific antibody secreting cells, in host response to non-lethal Plasmodium yoelii infection. We found that TACI deficiency not only resulted in higher peak parasitemia levels in P. yoelii challenged mice, but also led to a delay in parasite clearance and anti-P. yoelii Merozoite Surface Protein 1(C-terminal 19-kDa fragment [rMSP-119]) protein and anti-rMSP-119 and anti-P. yoelii IgG antibody development. There was also a delay in the generation of splenic high affinity antibody secreting cells that recognize rMSP-119 protein as compared to wild-type mice. Interestingly, coinciding with the delay in parasite clearance there was a delay in the resolution of T follicular helper (TFH) cell and germinal center (GC) B cell responses in TACI -/- mice. The persistence of TFH and GC B cells is likely a result of enhanced interaction between TFH and GC B cells because inducible costimulator ligand (ICOSL) expression was significantly higher on TACI -/- GC B cells than wild-type cells. The difference in the kinetics of GC reaction appeared to also impact the emergence of plasma cells (PC) because there was a delay in the generation of TACI -/- mice PC. Nevertheless, following the recovery from P. yoelii infection, TACI -/- and wild-type mice were both protected from a rechallenge infection. Establishment of protective B cell response was responsible for the resolution of parasitemia because B cells purified from recovered TACI -/- or wild-type mice were equally protective when introduced to naïve wild-type mice prior to P. yoelii challenge. Thus, despite the increased susceptibility of TACI -/- mice to P. yoelii infection and a delay in the development of protective antibody levels, TACI -/- mice are able to clear the infection and resist rechallenge infection.


Assuntos
Centro Germinativo/imunologia , Plasmodium yoelii/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Proteína Transmembrana Ativadora e Interagente do CAML/imunologia , Animais , Linfócitos B/imunologia , Ligante Coestimulador de Linfócitos T Induzíveis/imunologia , Malária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Plasmócitos/imunologia
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