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1.
J Infect Dis ; 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39250505

ABSTRACT

BACKGROUND: Chlamydia trachomatis (CT) is a globally prevalent sexually transmitted infection (STI) that can result in pelvic inflammatory disease, ectopic pregnancy and infertility in women. Currently, there is no prophylactic vaccine. METHODS: This study examined T cell immunity in a cohort of women recently infected with CT. Participants were screened against peptides spanning 33 of 894 possible CT proteins, either ex vivo or using short-term cell lines (STCL). CT-specific T cells were characterized by IFN-γ ELISpot and flow cytometry. RESULTS: Ex vivo CT-specific T cells were rarely detected; however, following in vitro expanded CT-specific T cells were detected by IFN-γ ELISpot in 90% (27/30) of participants. Notably, over 50% of participants had T cell responses targeting chlamydial protease-like activity factor (CPAF). T cell epitopes were dispersed across the CPAF protein. Flow cytometry analysis of STCL found CT-specific cells, were mainly CD4+, produced IFN-γ and TNF-α and were sustained over 12 months. Ex vivo analysis suggested CT-specific T cells mostly exhibited a central memory phenotype. CONCLUSION: Our results indicate that CT infection elicits low-frequency, persistent CD4 T cell responses in most women and that the secreted protein, CPAF, is an immunoprevalent CT antigen. Altogether, these data support development and testing of CT vaccines that enhance CD4 T cells against CPAF.

2.
Clin Exp Immunol ; 215(3): 279-290, 2024 02 19.
Article in English | MEDLINE | ID: mdl-37950348

ABSTRACT

CD8 T cells recognize infected and cancerous cells via their T-cell receptor (TCR), which binds peptide-MHC complexes on the target cell. The affinity of the interaction between the TCR and peptide-MHC contributes to the antigen sensitivity, or functional avidity, of the CD8 T cell. In response to peptide-MHC stimulation, the TCR-CD3 complex and CD8 co-receptor are downmodulated. We quantified CD3 and CD8 downmodulation following stimulation of human CD8 T cells with CMV, EBV, and HIV peptides spanning eight MHC restrictions, observing a strong correlation between the levels of CD3 and CD8 downmodulation and functional avidity, regardless of peptide viral origin. In TCR-transduced T cells targeting a tumor-associated antigen, changes in TCR-peptide affinity were sufficient to modify CD3 and CD8 downmodulation. Correlation analysis and generalized linear modeling indicated that CD3 downmodulation was the stronger correlate of avidity. CD3 downmodulation, simply measured using flow cytometry, can be used to identify high-avidity CD8 T cells in a clinical context.


Subject(s)
CD8-Positive T-Lymphocytes , Receptors, Antigen, T-Cell , Humans , Down-Regulation , Receptors, Antigen, T-Cell/genetics , CD8 Antigens/metabolism , Peptides/metabolism , CD3 Complex/metabolism
3.
Clin Sci (Lond) ; 136(11): 803-817, 2022 06 17.
Article in English | MEDLINE | ID: mdl-35543237

ABSTRACT

Calcium influx from depolarized CaV1.2 calcium channels triggers the contraction of vascular smooth muscle cells (VSMCs), which is important for maintaining vascular myogenic tone and blood pressure. The function of CaV1.2 channel can be subtly modulated by alternative splicing (AS), and its aberrant splicing involves in the pathogenesis of multiple cardiovascular diseases. The RNA-binding protein Rbfox1 is reported to regulate the AS events of CaV1.2 channel in the neuronal development, but its potential roles in vascular CaV1.2 channels and vasoconstriction remain undefined. Here, we detect Rbfox1 is expressed in rat vascular smooth muscles. Moreover, the protein level of Rbfox1 is dramatically decreased in the hypertensive small arteries from spontaneously hypertensive rats in comparison with normotensive ones from Wistar-Kyoto rats. In VSMCs, Rbfox1 could dynamically regulate the AS of CaV1.2 exons 9* and 33. By whole-cell patch clamp, we identify knockdown of Rbfox1 induces the hyperpolarization of CaV1.2 current-voltage relationship curve in VSMCs. Furthermore, siRNA-mediated knockdown of Rbfox1 increases the K+-induced constriction of rat mesenteric arteries. In summary, our results indicate Rbfox1 modulates vascular constriction by dynamically regulating CaV1.2 alternative exons 9* and 33. Therefore, our work elucidates the underlying mechanisms for CaV1.2 channels regulation and provides a potential therapeutic target for hypertension.


Subject(s)
Hypertension , Vasoconstriction , Alternative Splicing , Animals , Calcium/metabolism , Calcium Channels, L-Type/genetics , Calcium Channels, L-Type/metabolism , Constriction , Mesenteric Arteries/metabolism , Myocytes, Smooth Muscle/metabolism , Rats , Rats, Inbred WKY
4.
Blood ; 131(14): 1576-1586, 2018 04 05.
Article in English | MEDLINE | ID: mdl-29437595

ABSTRACT

Juvenile myelomonocytic leukemia (JMML), a rare and aggressive myelodysplastic/myeloproliferative neoplasm that occurs in infants and during early childhood, is characterized by excessive myelomonocytic cell proliferation. More than 80% of patients harbor germ line and somatic mutations in RAS pathway genes (eg, PTPN11, NF1, NRAS, KRAS, and CBL), and previous studies have identified several biomarkers associated with poor prognosis. However, the molecular pathogenesis of 10% to 20% of patients and the relationships among these biomarkers have not been well defined. To address these issues, we performed an integrated molecular analysis of samples from 150 JMML patients. RNA-sequencing identified ALK/ROS1 tyrosine kinase fusions (DCTN1-ALK, RANBP2-ALK, and TBL1XR1-ROS1) in 3 of 16 patients (18%) who lacked canonical RAS pathway mutations. Crizotinib, an ALK/ROS1 inhibitor, markedly suppressed ALK/ROS1 fusion-positive JMML cell proliferation in vitro. Therefore, we administered crizotinib to a chemotherapy-resistant patient with the RANBP2-ALK fusion who subsequently achieved complete molecular remission. In addition, crizotinib also suppressed proliferation of JMML cells with canonical RAS pathway mutations. Genome-wide methylation analysis identified a hypermethylation profile resembling that of acute myeloid leukemia (AML), which correlated significantly with genetic markers with poor outcomes such as PTPN11/NF1 gene mutations, 2 or more genetic mutations, an AML-type expression profile, and LIN28B expression. In summary, we identified recurrent activated ALK/ROS1 fusions in JMML patients without canonical RAS pathway gene mutations and revealed the relationships among biomarkers for JMML. Crizotinib is a promising candidate drug for the treatment of JMML, particularly in patients with ALK/ROS1 fusions.


Subject(s)
Cell Proliferation , Crizotinib/pharmacology , Gene Expression Profiling , Leukemia, Myelomonocytic, Juvenile/genetics , Leukemia, Myelomonocytic, Juvenile/metabolism , Mutation , Oncogene Proteins, Fusion , Protein Kinase Inhibitors/pharmacology , Adolescent , Cell Proliferation/drug effects , Cell Proliferation/genetics , Child , Child, Preschool , DNA Methylation/drug effects , DNA Methylation/genetics , DNA, Neoplasm/genetics , DNA, Neoplasm/metabolism , Female , Genome-Wide Association Study , Humans , Infant , Leukemia, Myelomonocytic, Juvenile/drug therapy , Male , Oncogene Proteins, Fusion/biosynthesis , Oncogene Proteins, Fusion/genetics
5.
Alzheimer Dis Assoc Disord ; 34(2): 188-190, 2020.
Article in English | MEDLINE | ID: mdl-31651418

ABSTRACT

The clinical presentation in Chinese patients with sporadic Creutzfeldt-Jakob disease (sCJD) may be unique due to the big difference in the codon 129 polymorphism of the prion protein gene (PRNP). This study retrospectively reviewed 26 cases of sCJD diagnosed in a single center in recent years. All 26 sCJD patients received brain magnetic resonance imaging scan, cerebrospinal fluid 14-3-3 protein detection, electroencephalogram, and PRNP gene screening. The codon 129 polymorphism were all homozygous MM in 26 sCJD patients. The main onset symptoms of sCJD patients were rapidly progressive dementia, visual impairment, and cerebellar ataxia. At the time of diagnosis, the incidence of myoclonus and akinetic mutism were relatively low (<50%). For auxiliary examinations, the positive rate of the typical magnetic resonance imaging (MRI) abnormalities, cerebrospinal fluid 14-3-3 protein, and electroencephalogram-periodic sharp wave complex was 96%, 64%, and 50%, respectively. As MM genotype is dominant and brain MRI is sensitive, brain MRI seems to play a major role in diagnosis of sCJD in Chinese.


Subject(s)
Brain/physiopathology , Creutzfeldt-Jakob Syndrome/cerebrospinal fluid , Creutzfeldt-Jakob Syndrome/diagnosis , Magnetic Resonance Imaging , Prion Proteins/genetics , 14-3-3 Proteins/cerebrospinal fluid , 14-3-3 Proteins/metabolism , Aged , Ataxia/etiology , China/ethnology , Creutzfeldt-Jakob Syndrome/genetics , Electroencephalography , Female , Humans , Male , Middle Aged , Myoclonus/etiology , Polymorphism, Single Nucleotide , Retrospective Studies
7.
J Cell Physiol ; 232(9): 2581-2589, 2017 Sep.
Article in English | MEDLINE | ID: mdl-27770612

ABSTRACT

Autophagy, identified as type II programmed cell death, has already been known to be involved in the pathophysiology of preeclampsia (PE), which is a gestational disease with high morbidity. The present study aims to investigate the functional role of let-7i, a miRNA, in trophoblastic autophagy. Placental tissue used in this study was collected from patients with severe preeclampsia (SPE) or normal pregnant women. A decreased level of let-7i was found in placenta of SPE. In addition, autophagic vacuoles were observed in SPE and the expression of microtubule associated protein 1 light chain 3 (LC3) II/I was elevated. In vitro, let-7i mimics suppressed the autophagic activities in human HTR-8/SVneo trophoblast cell line (HTR-8) and human placental choriocarcinoma cell line JEG-3, whereas let-7i inhibitor enhanced the activities. As a potential target of let-7i, autophagy-related 4B cysteine peptidase (Atg4B) had an increased expression level in SPE. As expected, the increased expression of Atg4B was negatively regulated by let-7i using dual luciferase reporter assay. Furthermore, these trophoblast-like cells transfected with the let-7i mimic or inhibitors resulted in a significant change of Atg4B in both mRNA and protein level. More importantly, Atg4B overexpression could partly reverse let-7i mimic-reduced LC3II/I levels; whereas Atg4B silencing partly attenuated let-7i inhibitor-induced the level of LC3II/I expression. Taken together, these findings suggest that let-7i is able to regulate autophagic activity via regulating Atg4B expression, which might contribute to the pathogenesis of PE. J. Cell. Physiol. 232: 2581-2589, 2017. © 2016 Wiley Periodicals, Inc.


Subject(s)
Autophagy-Related Proteins/metabolism , Autophagy , Cysteine Endopeptidases/metabolism , MicroRNAs/metabolism , Pre-Eclampsia/metabolism , Trophoblasts/metabolism , Adult , Autophagy-Related Proteins/genetics , Case-Control Studies , Cell Line, Tumor , Cysteine Endopeptidases/genetics , Down-Regulation , Female , Gene Expression Regulation, Developmental , Humans , MicroRNAs/genetics , Microtubule-Associated Proteins/metabolism , Pre-Eclampsia/genetics , Pre-Eclampsia/pathology , Pregnancy , RNA Interference , Signal Transduction , Transfection , Trophoblasts/pathology
8.
Br J Haematol ; 176(2): 248-257, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27861730

ABSTRACT

We assessed the clinical utility of next-generation sequencing (NGS)-based monitoring of minimal residual disease (MRD) in a uniformly treated cohort of 79 patients with paediatric B-cell acute lymphoblastic leukaemia. Bone marrow samples were collected at the time of diagnosis, days 33 and 80, pre- (4-5 months) and post- (24 months) maintenance therapy time points, and at relapse. We identified leukaemia-specific CDR3 sequences in 72 of 79 patients (91%) and detected MRD in 59 of 232 samples. Although MRD was detected in 28 of 55 samples (51%) on day 33, the frequencies of MRD detection decreased to 25% (16/65) at day 80, 19% (11/58) at 4-5 months and 7·4% (4/54) at 24 months. In a univariate analysis, positive MRD results on day 80 [relative risk (RR) 95% confidence interval (CI) = 7·438 (2·561-21·6), P < 0·001], at 4-5 months [RR (95% CI) = 10·24 (3·374-31·06), P < 0·001], and at 24 months [RR (95% CI) = 19·26 (4·974-74·59), P < 0·001] exhibited statistically significant associations with inferior leukaemia-free survival; this was confirmed using a Cox proportional hazard model. Our study suggests the promising potential of NGS-MRD for patients with B-cell ALL.


Subject(s)
DNA, Neoplasm , Neoplasm, Residual/diagnosis , Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Adolescent , B-Lymphocytes/pathology , Bone Marrow Examination , Child , Child, Preschool , DNA, Neoplasm/analysis , Disease-Free Survival , Female , Humans , Infant , Male , Retrospective Studies , Sequence Analysis, DNA , Time Factors
9.
Genet Med ; 19(7): 796-802, 2017 07.
Article in English | MEDLINE | ID: mdl-28102861

ABSTRACT

PURPOSE: Precise genetic diagnosis of inherited bone marrow failure syndromes (IBMFS), a heterogeneous group of genetic disorders, is challenging but essential for precise clinical decision making. METHODS: We analyzed 121 IBMFS patients using a targeted sequencing covering 184 associated genes and 250 IBMFS patients using whole-exome sequencing (WES). RESULTS: We achieved successful genetic diagnoses for 53 of 121 patients (44%) using targeted sequencing and for 68 of 250 patients (27%) using WES. In the majority of cases (targeted sequencing: 45/53, 85%; WES: 63/68, 93%), the detected variants were concordant with, and therefore supported, the clinical diagnoses. However, in the remaining 13 cases (8 patients by target sequencing and 5 patients by WES), the clinical diagnoses were incompatible with the detected variants. CONCLUSION: Our approach utilizing targeted sequencing and WES achieved satisfactory diagnostic rates and supported the efficacy of massive parallel sequencing as a diagnostic tool for IBMFS.Genet Med advance online publication 19 January 2017.


Subject(s)
Anemia, Aplastic/diagnosis , Anemia, Aplastic/genetics , Bone Marrow Diseases/diagnosis , Bone Marrow Diseases/genetics , Hemoglobinuria, Paroxysmal/diagnosis , Hemoglobinuria, Paroxysmal/genetics , High-Throughput Nucleotide Sequencing/statistics & numerical data , Bone Marrow Failure Disorders , Exome/genetics , Female , Genetic Testing , High-Throughput Nucleotide Sequencing/methods , Humans , Male , Mutation/genetics , Sequence Analysis, DNA/methods , Exome Sequencing/methods
10.
Pediatr Blood Cancer ; 63(4): 659-64, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26575027

ABSTRACT

BACKGROUND: Immunosuppressive therapy (IST) is commonly used for patients with acquired severe aplastic anemia (SAA). Because the clinical response rate and therapeutic outcome for individual patients to IST varies, an in vitro test that identifies potential responders would be desirable. METHODS: We evaluated the relationship between thrombopoietin (TPO) levels at the time of diagnosis and the response to IST at 6 months in 85 children (median age, 9.0 years; range, 1.0-15.5 years) with acquired SAA using enzyme-linked immunosorbent assay. Thirty-one age-matched healthy individuals were used as controls. All patients received antithymocyte globulin and cyclosporine. RESULTS: Overall, 39 patients (45.9%) responded to IST at 6 months. TPO plasma levels were significantly higher in nonresponders than in responders (1,555.8 vs. 1,284.7 pg/ml, respectively; P = 0.031). Multivariate analysis identified the TPO levels of >1,796.7 pg/ml (TPO-high group, 20 patients; odds ratio (OR), 8.285; 95% confidence interval (CI), 2.114-32.904; P = 0.002) as independent poor predictors of IST response at 6 months. Moreover, the TPO-high group was associated with lower 5-year failure-free survival rates (30% vs. 68%, P = 0.012) compared with the TPO-low group. CONCLUSION: The measurement of TPO levels at diagnosis is useful for predicting the response to IST in children with SAA and may help in decision making.


Subject(s)
Anemia, Aplastic/blood , Anemia, Aplastic/drug therapy , Biomarkers/blood , Immunosuppressive Agents/therapeutic use , Thrombopoietin/blood , Adolescent , Antilymphocyte Serum/therapeutic use , Child , Child, Preschool , Cyclosporine/therapeutic use , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Proportional Hazards Models , Treatment Outcome
11.
Pediatr Blood Cancer ; 63(4): 652-8, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26485171

ABSTRACT

BACKGROUND: Distinguishing hypocellular refractory cytopenia of childhood (RCC) from aplastic anemia (AA) is challenging. Thus far, no studies have compared the cytokine profiles in patients with AA to those with hypocellular RCC. In the present study, we addressed whether thrombopoietin (TPO) and interleukin 17 (IL-17) plasma levels are useful for differentiating between the two diseases. METHODS: We measured the endogenous plasma concentrations of TPO and IL-17 in 29 patients with AA, 34 patients with hypocellular RCC, and 31 healthy controls using sensitive enzyme-linked immunosorbent assays. RESULTS: The TPO and IL-17 plasma levels were significantly lower in patients with hypocellular RCC than in patients with AA (P < 0.001 and P = 0.007, respectively). The multivariate logistic regression analysis identified moderate disease severity, TPO levels of <1,369.8 pg/ml (TPO-low group, n = 32; odds ratio (OR), 13.40; 95% confidence intervals (CI), 3.001-51.254; P < 0.001), and IL-17 levels of <22.2 pg/ml (IL-17-low group, n = 33; OR, 4.11; 95% CI, 1.033-19.404; P = 0.031) as independent factors discriminating hypocellular RCC from AA. Importantly, 25 (78.1%) of 32 patients in the TPO-low group and 25 (75.8%) of 33 patients in the IL-17-low group were diagnosed as having hypocellular RCC. Moreover, 22 (71%) of 31 patients in the TPO-high group and 21 (70%) of 30 patients in the IL-17-high group were diagnosed as having AA. CONCLUSIONS: TPO and IL-17 levels are useful for differentiating hypocellular RCC from AA. Prospective studies are required to confirm our findings.


Subject(s)
Anemia, Aplastic/blood , Anemia, Aplastic/diagnosis , Interleukin-17/blood , Myelodysplastic Syndromes/diagnosis , Thrombopoietin/blood , Biomarkers/blood , Child , Child, Preschool , Diagnosis, Differential , Enzyme-Linked Immunosorbent Assay , Female , Humans , Infant , Male , Myelodysplastic Syndromes/blood
12.
Pediatr Transplant ; 20(1): 105-13, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26518333

ABSTRACT

We analyzed the correlation between rabbit ATG (rATG) serum levels and clinical outcomes in 37 children who received rATG at a total dose of 10 or 15 mg/kg during HSCT conditioning from an alternative donor. Fourteen patients had advanced malignant diseases, 13 had severe AA, and 10 had inherited disorders. Complete engraftment was achieved in all patients, and no rejection occurred. The cumulative incidence of grades II-IV acute GVHD and extensive chronic GVHD was 27% (95% CI, 12.5-39.6%) and 8.1% (95% CI, 0-23.1%), respectively. Multivariate analysis identified lower rATG levels at week 4 as an independent risk factor in the development of grades II-IV acute GVHD (p = 0.037). Serious infections were not observed in any patient following HSCT. No correlation was found between EBV reactivation and rATG levels at week 2 and week 4 after HSCT. Furthermore, no correlation was found between relapse and rATG levels two and four wk post-transplantation. The probability of five-yr OS among patients was 70.3% (95% CI, 59.8-79.2%). Our results suggest that targeted rATG administration may protect patients from severe acute GVHD without increasing the risk of EBV reactivation or relapse.


Subject(s)
Antilymphocyte Serum/blood , Hematopoietic Stem Cell Transplantation/methods , Neoplasms/therapy , Adolescent , Animals , Antilymphocyte Serum/therapeutic use , Child , Child, Preschool , Female , Graft vs Host Disease , Hematologic Neoplasms/complications , Hematologic Neoplasms/therapy , Humans , Infant , Male , Multivariate Analysis , Neoplasm Recurrence, Local , Rabbits , Recurrence , Retrospective Studies , Risk Factors , Tissue Donors , Transplantation Conditioning , Transplantation, Homologous , Treatment Outcome , Young Adult
13.
Adv Exp Med Biol ; 904: 1-22, 2016.
Article in English | MEDLINE | ID: mdl-26900059

ABSTRACT

For the past century, scientists have developed a variety of methods to evaluate itch and pain in both animal models and human subjects to throw light on some of the most important pathways mediating these unpleasant sensations. Discoveries in the mechanisms underlying itch and pain in both physiological and pathological conditions relied greatly upon these studies and may eventually lead to the discovery of new therapeutics. However, it was a much more complicated job to access itch and pain in animal models than in human subjects due to the subjective nature of these sensations. The results could be contradictory or even misleading when applying different methodologies in animal models, especially under pathological conditions with a mixed sensation of itch and pain. This chapter introduces and evaluates some of the classical and newly designed methodologies to access the sensation of itch and pain in animal models as well as human subjects.


Subject(s)
Mice/physiology , Models, Animal , Nociception/physiology , Pain/physiopathology , Pruritus/physiopathology , Rats/physiology , Analgesics/pharmacology , Analgesics/therapeutic use , Animals , Antipruritics/pharmacology , Antipruritics/therapeutic use , Avoidance Learning , Capsaicin/toxicity , Conditioning, Classical , Emotions , Histamine/toxicity , Histamine Antagonists/pharmacology , Histamine Antagonists/therapeutic use , Humans , Mice/psychology , Nontherapeutic Human Experimentation , Organ Specificity , Pain/drug therapy , Pain/etiology , Pain/psychology , Pain Measurement/methods , Physical Stimulation/adverse effects , Pruritus/drug therapy , Pruritus/etiology , Pruritus/psychology , Rats/psychology , Species Specificity
14.
Tumour Biol ; 36(2): 1279-88, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25352028

ABSTRACT

Berberine has drawn extensive attention toward their wide range of biochemical and pharmacological effects, including antineoplastic effect in recent years, but the precise mechanisms remain unclear. Treatment of human breast cancer cells (MCF-7 and MDA-MB-231 cells) with berberine induced inhibition of cell viability in concentration- and time-dependent manner irrespective of their estrogen receptor (ER) expression. Hoechst33342 staining confirmed berberine induced breast cancer cell apoptosis in time-dependent manner. Because apoptosis induction is considered to be a crucial strategy for cancer prevention and therapy, berberine may be an effective chemotherapeutic agent against breast cancer. To explore the precise mechanism, berberine-induced oxidative stress and mitochondrial-related apoptotic pathway in human breast cancer cells were investigated in this study. In both MCF-7 and MDA-MB-231 cells, berberine increased the production of reactive oxygen species (ROS), which activated the pro-apoptotic JNK signaling. Phosphorylated JNK triggered mitochondria membrane potential (ΔΨm) depolarization and downregulation expression of anti-apoptotic protein Bcl-2 concomitant with the upregulation expression of pro-apoptotic protein Bax. Downregulation of anti-apoptotic Bcl-2 family protein in parallel with loss of ΔΨm, leading to increased the release of cytochrome c and apoptosis-inducing factor (AIF) from mitochondria, and eventually triggered the caspase-dependent and caspase-independent apoptosis. Taken together, our study reveled that berberine exerted an antitumor activity in breast cancer cells by reactive oxygen species generation and mitochondrial-related apoptotic pathway. These finding provide an insight into the potential of berberine for breast cancer therapy.


Subject(s)
Apoptosis/drug effects , Berberine/administration & dosage , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Caspase 3/biosynthesis , Cell Survival/drug effects , Female , Humans , MCF-7 Cells , Membrane Potential, Mitochondrial/drug effects , Proto-Oncogene Proteins c-bcl-2/biosynthesis , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects
15.
Haematologica ; 100(12): 1546-52, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26315930

ABSTRACT

Acquired aplastic anemia is an immune-mediated disease characterized by severe defects in stem cell number resulting in hypocellular marrow and peripheral blood cytopenias. Minor paroxysmal nocturnal hemoglobinuria populations and a short telomere length were identified as predictive biomarkers of immunosuppressive therapy responsiveness in aplastic anemia. We enrolled 113 aplastic anemia patients (63 boys and 50 girls) in this study to evaluate their response to immunosuppressive therapy. The paroxysmal nocturnal hemoglobinuria populations and telomere length were detected by flow cytometry. Forty-seven patients (42%) carried a minor paroxysmal nocturnal hemoglobinuria population. The median telomere length of aplastic anemia patients was -0.99 standard deviation (SD) (range -4.01-+3.01 SD). Overall, 60 patients (53%) responded to immunosuppressive therapy after six months. Multivariate logistic regression analysis identified the absence of a paroxysmal nocturnal hemoglobinuria population and a shorter telomere length as independent unfavorable predictors of immunosuppressive therapy response at six months. The cohort was stratified into a group of poor prognosis (paroxysmal nocturnal hemoglobinuria negative and shorter telomere length; 37 patients) and good prognosis (paroxysmal nocturnal hemoglobinuria positive and/or longer telomere length; 76 patients), respectively. The response rates of the poor prognosis and good prognosis groups at six months were 19% and 70%, respectively (P<0.001). The combined absence of a minor paroxysmal nocturnal hemoglobinuria population and a short telomere length is an efficient predictor of poor immunosuppressive therapy response, which should be considered while deciding treatment options: immunosuppressive therapy or first-line hematopoietic stem cell transplantation. The trial was registered in www.umin.ac.jp with number UMIN000017972.


Subject(s)
Anemia, Aplastic , Hemoglobinuria, Paroxysmal , Immunosuppression Therapy , Telomere Homeostasis , Telomere/metabolism , Adolescent , Anemia, Aplastic/diagnosis , Anemia, Aplastic/metabolism , Anemia, Aplastic/therapy , Child , Child, Preschool , Female , Hemoglobinuria, Paroxysmal/diagnosis , Hemoglobinuria, Paroxysmal/metabolism , Hemoglobinuria, Paroxysmal/therapy , Humans , Infant , Male , Prognosis
16.
Blood ; 120(7): 1485-8, 2012 Aug 16.
Article in English | MEDLINE | ID: mdl-22753870

ABSTRACT

Juvenile myelomonocytic leukemia (JMML) is a rare pediatric myeloid neoplasm characterized by excessive proliferation of myelomonocytic cells. Somatic mutations in genes involved in GM-CSF signal transduction, such as NRAS, KRAS, PTPN11, NF1, and CBL, have been identified in more than 70% of children with JMML. In the present study, we report 2 patients with somatic mosaicism for oncogenic NRAS mutations (G12D and G12S) associated with the development of JMML. The mutated allele frequencies quantified by pyrosequencing were various and ranged from 3%-50% in BM and other somatic cells (ie, buccal smear cells, hair bulbs, or nails). Both patients experienced spontaneous improvement of clinical symptoms and leukocytosis due to JMML without hematopoietic stem cell transplantation. These patients are the first reported to have somatic mosaicism for oncogenic NRAS mutations. The clinical course of these patients suggests that NRAS mosaicism may be associated with a mild disease phenotype in JMML.


Subject(s)
Leukemia, Myelomonocytic, Juvenile/genetics , Mosaicism , Mutation/genetics , Oncogenes/genetics , ras Proteins/genetics , Base Sequence , Child , DNA Mutational Analysis , Humans , Infant , Male , Molecular Sequence Data
17.
Haematologica ; 99(8): 1312-6, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24816243

ABSTRACT

Predicting the response to immunosuppressive therapy could provide useful information to help the clinician define treatment strategies for patients with aplastic anemia. In our current study, we evaluated the relationship between telomere length of lymphocytes at diagnosis and the response to immunosuppressive therapy in 64 children with aplastic anemia, using flow fluorescence in situ hybridization. Median age of patients was ten years (range 1.5-16.2 years). Severity of the disease was classified as very severe in 23, severe in 21, and moderate in 20 patients. All patients were enrolled in multicenter studies using antithymocyte globulin and cyclosporine. The response rate to immunosuppressive therapy at six months was 52% (33 of 64). The probability of 5-year failure-free survival and overall survival were 56% (95% confidence interval (CI): 41-69%) and 97% (95%CI: 87-99%), respectively. Median telomere length in responders was -0.4 standard deviation (SD) (-2.7 to +3.0 SD) and -1.5 SD (-4.0 to +1.6 (SD)) in non-responders (P<0.001). Multivariate analysis showed that telomere length shorter than -1.0 SD (hazard ratio (HR): 22.0; 95%CI: 4.19-115; P<0.001), platelet count at diagnosis less than 25×10(9)/L (HR: 13.9; 95%CI: 2.00-96.1; P=0.008), and interval from diagnosis to immunosuppressive therapy longer than 25 days (HR: 4.81; 95%CI: 1.15-20.1; P=0.031) were the significant variables for poor response to immunosuppressive therapy. Conversely to what has been found in adult patients, measurement of the telomere length of lymphocytes at diagnosis is a promising assay in predicting the response to immunosuppressive therapy in children with aplastic anemia.


Subject(s)
Anemia, Aplastic/diagnosis , Anemia, Aplastic/drug therapy , Immunosuppressive Agents/therapeutic use , Lymphocytes/drug effects , Telomere Homeostasis/drug effects , Telomere/drug effects , Adolescent , Anemia, Aplastic/immunology , Child , Child, Preschool , Female , Humans , Immunosuppressive Agents/pharmacology , Infant , Lymphocytes/immunology , Lymphocytes/pathology , Male , Predictive Value of Tests , Telomere/immunology , Telomere/pathology , Telomere Homeostasis/physiology , Treatment Outcome
18.
Proc Natl Acad Sci U S A ; 108(40): 16723-8, 2011 Oct 04.
Article in English | MEDLINE | ID: mdl-21933959

ABSTRACT

Ipilimumab, a monoclonal antibody against cytotoxic T lymphocyte antigen 4 (CTLA-4), has been shown to improve survival in patients with advanced metastatic melanoma. It also enhances immunity to NY-ESO-1, a cancer/testis antigen expressed in a subset of patients with melanoma. To characterize the association between immune response and clinical outcome, we first analyzed NY-ESO-1 serum antibody by ELISA in 144 ipilimumab-treated patients with melanoma and found 22 of 140 (16%) seropositive at baseline and 31 of 144 (22%) seropositive following treatment. These NY-ESO-1-seropositive patients had a greater likelihood of experiencing clinical benefit 24 wk after ipilimumab treatment than NY-ESO-1-seronegative patients (P = 0.02, relative risk = 1.8, two-tailed Fisher test). To understand why some patients with NY-ESO-1 antibody failed to experience clinical benefit, we analyzed NY-ESO-1-specific CD4(+) and CD8(+) T-cell responses by intracellular multicytokine staining in 20 NY-ESO-1-seropositive patients and found a surprising dissociation between NY-ESO-1 antibody and CD8 responses in some patients. NY-ESO-1-seropositive patients with associated CD8(+) T cells experienced more frequent clinical benefit (10 of 13; 77%) than those with undetectable CD8(+) T-cell response (one of seven; 14%; P = 0.02; relative risk = 5.4, two-tailed Fisher test), as well as a significant survival advantage (P = 0.01; hazard ratio = 0.2, time-dependent Cox model). Together, our data suggest that integrated NY-ESO-1 immune responses may have predictive value for ipilimumab treatment and argue for prospective studies in patients with established NY-ESO-1 immunity. The current findings provide a strong rationale for the clinical use of modulators of immunosuppression with concurrent approaches to favor tumor antigen-specific immune responses, such as vaccines or adoptive transfer, in patients with cancer.


Subject(s)
Antibodies, Monoclonal/pharmacology , Antigens, Neoplasm/immunology , CD8-Positive T-Lymphocytes/immunology , CTLA-4 Antigen/immunology , Melanoma/immunology , Membrane Proteins/immunology , Adult , Aged , Aged, 80 and over , Antibodies, Monoclonal/immunology , Enzyme-Linked Immunosorbent Assay , Humans , Immunohistochemistry , Ipilimumab , Middle Aged , Proportional Hazards Models , Survival Analysis
19.
Open Forum Infect Dis ; 11(5): ofae212, 2024 May.
Article in English | MEDLINE | ID: mdl-38756763

ABSTRACT

Background: Persistence of HIV-1 in reservoirs necessitates life-long antiretroviral therapy (ART). There are conflicting data using genetic analysis on whether persistence includes an actively replicating reservoir with strong evidence arguing against replication. Methods: We investigated the possibility of ongoing viral evolution during suppressive therapy by comparing near full-length viral genomic sequences using phylogenetic analysis of viral RNA in plasma before therapy initiation early after infection and from virus induced to grow from the latent reservoir after a period of suppressive ART. We also focused our analysis on evidence of selective pressure by drugs in the treatment regimen and at sites of selective pressure by the adaptive immune response. Results: Viral genomes induced to grow from the latent reservoir from 10 participants with up to 9 years on suppressive ART were highly similar to the nearly homogeneous sequences in plasma taken early after infection at ART initiation. This finding was consistent across the entire genome and when the analysis focused on sites targeted by the drug regimen and by host selective pressure of antibody and cytotoxic T cells. The lack of viral evolution away from pretherapy sequences in spite of demonstrated selective pressure is most consistent with a lack of viral replication during reservoir persistence. Conclusions: These results do not support ongoing viral replication as a mechanism of HIV-1 persistence during suppressive ART.

20.
Stem Cell Reports ; 19(7): 957-972, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38876108

ABSTRACT

Induced pluripotent stem cell (iPSC)-derived motor neurons (MNs) from patients with amyotrophic lateral sclerosis (ALS) and the C9ORF72 hexanucleotide repeat expansion (HRE) have multiple cellular phenotypes, but which of these accurately reflect the biology underlying the cell-specific vulnerability of ALS is uncertain. We therefore compared phenotypes due to the C9ORF72 HRE in MNs with sensory neurons (SNs), which are relatively spared in ALS. The iPSC models were able to partially reproduce the differential gene expression seen between adult SNs and MNs. We demonstrated that the typical hallmarks of C9ORF72-ALS, including RNA foci and dipeptide formation, as well as specific axonal transport defects, occurred equally in MNs and SNs, suggesting that these in vitro phenotypes are not sufficient to explain the cell-type selectivity of ALS in isolation.


Subject(s)
Amyotrophic Lateral Sclerosis , Axonal Transport , C9orf72 Protein , DNA Repeat Expansion , Induced Pluripotent Stem Cells , Motor Neurons , Phenotype , Sensory Receptor Cells , Induced Pluripotent Stem Cells/metabolism , Induced Pluripotent Stem Cells/cytology , C9orf72 Protein/genetics , C9orf72 Protein/metabolism , Humans , Motor Neurons/metabolism , Sensory Receptor Cells/metabolism , Amyotrophic Lateral Sclerosis/genetics , Amyotrophic Lateral Sclerosis/metabolism , DNA Repeat Expansion/genetics
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