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1.
Epilepsy Behav ; 103(Pt A): 106864, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31937513

RESUMO

OBJECTIVE: The objective of this analysis was to provide a comprehensive analysis of safety data for adjunctive brivaracetam (BRV), an antiepileptic drug (AED) of the racetam class, for treatment of focal seizures in patients with epilepsy. METHODS: Data were pooled from two phase II, placebo-controlled, double-blind, dose-ranging trials (N01114 [ClinicalTrials.gov: NCT00175929], N01193 [NCT00175825]) and three phase III, placebo-controlled, double-blind, 12-week trials (N01252 [NCT00490035], N01253 [NCT00464269], and N01358 [NCT01261325]) in patients aged ≥16 years with focal seizures, as well as a phase III, placebo-controlled, double-blind, 16-week trial in patients aged ≥16 years with focal or generalized epilepsy (N01254 [NCT00504881]). Data are presented for the approved therapeutic dose range of 50-200 mg/day. Data for BRV administered intravenously (25-150 mg doses) were pooled separately from one phase III trial (N01258 NCT01405508]) and two clinical pharmacology trials (N01256 [Part B] [UCB Pharma, data on file]; EP0007 [NCT01796899]). Adverse events (AEs) of interest were summarized in relevant categories. RESULTS: The safety pool comprised 1957 patients: 1271 receiving adjunctive BRV and 686 receiving placebo. Overall, the incidence of treatment-emergent adverse events (TEAEs) was 66.9% with BRV versus 62.8% with placebo. The most frequently reported TEAEs with BRV (≥5% of patients) versus placebo were somnolence (13.3% vs. 7.9%), headache (10.5% vs. 11.5%), dizziness (10.0% vs. 7.0%), and fatigue (8.2% vs. 4.2%). Incidence of psychiatric disorder-related TEAEs was 11.3% with BRV versus 8.2% with placebo. Behavioral disorder-related TEAE incidence was low (4.0% with BRV vs. 2.5% with placebo). Irritability was reported in 2.7% of BRV-treated patients vs. 1.5% of patients receiving placebo; anger, aggression, and agitation were each reported by ≤1% of patients receiving BRV. Treatment-emergent adverse events potentially associated with psychosis were psychotic disorder (three patients on BRV vs. two patients on placebo), auditory hallucination, illusion, visual hallucination (one patient each on BRV), epileptic psychosis, and hallucination (one patient each on placebo). No additional safety concerns were identified in patients with intravenous (IV) BRV administration (n = 104). CONCLUSIONS: These safety data for adjunctive BRV support its acceptable safety and tolerability profile.


Assuntos
Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/efeitos adversos , Epilepsia/tratamento farmacológico , Pirrolidinonas/administração & dosagem , Pirrolidinonas/efeitos adversos , Administração Intravenosa , Ensaios Clínicos Fase II como Assunto/métodos , Ensaios Clínicos Fase III como Assunto/métodos , Tontura/induzido quimicamente , Método Duplo-Cego , Quimioterapia Combinada , Epilepsia/diagnóstico , Fadiga/induzido quimicamente , Humanos , Resultado do Tratamento
2.
J Virol ; 91(21)2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28794027

RESUMO

Dominant antibody responses in vaccinees who received the HIV-1 multiclade (A, B, and C) envelope (Env) DNA/recombinant adenovirus virus type 5 (rAd5) vaccine studied in HIV-1 Vaccine Trials Network (HVTN) efficacy trial 505 (HVTN 505) targeted Env gp41 and cross-reacted with microbial antigens. In this study, we asked if the DNA/rAd5 vaccine induced a similar antibody response in rhesus macaques (RMs), which are commonly used as an animal model for human HIV-1 infections and for testing candidate HIV-1 vaccines. We also asked if gp41 immunodominance could be avoided by immunization of neonatal RMs during the early stages of microbial colonization. We found that the DNA/rAd5 vaccine elicited a higher frequency of gp41-reactive memory B cells than gp120-memory B cells in adult and neonatal RMs. Analysis of the vaccine-induced Env-reactive B cell repertoire revealed that the majority of HIV-1 Env-reactive antibodies in both adult and neonatal RMs were targeted to gp41. Interestingly, a subset of gp41-reactive antibodies isolated from RMs cross-reacted with host antigens, including autologous intestinal microbiota. Thus, gp41-containing DNA/rAd5 vaccine induced dominant gp41-microbiota cross-reactive antibodies derived from blood memory B cells in RMs as observed in the HVTN 505 vaccine efficacy trial. These data demonstrated that RMs can be used to investigate gp41 immunodominance in candidate HIV-1 vaccines. Moreover, colonization of neonatal RMs occurred within the first week of life, and immunization of neonatal RMs during this time also induced a dominant gp41-reactive antibody response.IMPORTANCE Our results are critical to current work in the HIV-1 vaccine field evaluating the phenomenon of gp41 immunodominance induced by HIV-1 Env gp140 in RMs and humans. Our data demonstrate that RMs are an appropriate animal model to study this phenomenon and to determine the immunogenicity in new HIV-1 Env trimer vaccine designs. The demonstration of gp41 immunodominance in memory B cells of both adult and neonatal RMs indicated that early vaccination could not overcome gp41 dominant responses.


Assuntos
Vacinas contra a AIDS/administração & dosagem , Adenoviridae/genética , DNA Viral/genética , Anticorpos Anti-HIV/imunologia , Proteína gp41 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Adenoviridae/imunologia , Animais , Animais Recém-Nascidos , Formação de Anticorpos/imunologia , Sequência de Bases , Reações Cruzadas/imunologia , DNA Viral/imunologia , Feminino , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , Humanos , Macaca mulatta , Vacinação
3.
Epilepsy Behav ; 80: 129-134, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29414542

RESUMO

OBJECTIVE: The objective was to assess the efficacy and safety of adjunctive brivaracetam (BRV) with concomitant use of lamotrigine (LTG) or topiramate (TPM) in patients with uncontrolled focal seizures. METHODS: Data were pooled from three randomized, placebo-controlled Phase III studies (NCT00490035/N01252, NCT00464269/N01253, NCT01261325/N01358) of adults with focal (partial-onset) seizures. Patients taking concomitant levetiracetam were excluded from the efficacy populations, but included in the safety populations. This post-hoc analysis reports data from patients taking BRV in the approved therapeutic range (50-200mg/day) concomitantly with LTG or TPM. RESULTS: The number of patients in each of the three BRV dosage groups was small, particularly for the TPM subgroup. Mean percent reduction over placebo in baseline-adjusted focal seizure frequency/28days for BRV 50, 100, and 200mg/day was 8.7, 5.3, and 8.9 in the LTG subgroup (n=220), and 8.4, 21.3, and -4.2 in the TPM subgroup (n=122). The ≥50% responder rate with concomitant LTG or TPM with BRV 50, 100, and 200mg/day or placebo was LTG: 28.1%, 36.1%, 34.1%, and 29.1%; and TPM: 14.3%, 44.4%, 25.0%, and 17.5%. There were numerically ≥50%, ≥75%, ≥90%, and 100% responder rates for patients taking BRV ≥50mg/day compared with placebo in both subgroups. In the LTG and TPM safety populations (n=245 versus n=125), treatment-emergent adverse events (TEAEs) were reported with LTG 68.7% versus 68.4%, and TPM 65.6% versus 57.8% (BRV ≥50mg/day versus placebo). Discontinuations due to TEAEs versus placebo were LTG 7.3% versus 6.3% and TPM 8.2% versus 4.7%. The three most frequently reported TEAEs for both subgroups were somnolence, dizziness, and fatigue. Of these, the incidence of fatigue in the LTG population appeared to increase with dose. SIGNIFICANCE: In this post-hoc pooled analysis, BRV administered with concomitant LTG or TPM reduced seizure frequency and was generally well tolerated for BRV doses of 50-200mg/day.


Assuntos
Anticonvulsivantes/uso terapêutico , Lamotrigina/uso terapêutico , Pirrolidinonas/uso terapêutico , Convulsões/tratamento farmacológico , Topiramato/uso terapêutico , Adulto , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/efeitos adversos , Tontura/induzido quimicamente , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada , Fadiga/induzido quimicamente , Feminino , Humanos , Lamotrigina/administração & dosagem , Lamotrigina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Pirrolidinonas/administração & dosagem , Pirrolidinonas/efeitos adversos , Sonolência , Topiramato/administração & dosagem , Topiramato/efeitos adversos , Resultado do Tratamento , Adulto Jovem
4.
Epilepsia ; 58(2): e21-e25, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27988967

RESUMO

Time to onset of sustained ≥50% responder status (SRS) was assessed for the pooled patient population receiving brivaracetam (BRV) 50, 100, or 200 mg/day or placebo in three randomized phase III studies (NCT00464269, NCT00490035, and NCT01261325). Patients were aged ≥16 years with well-characterized focal (partial-onset) seizures (FS) uncontrolled by 1-2 concomitant antiepileptic drugs. After an 8-week baseline period, patients received study drug without up-titration for a 12-week (84-day) treatment period. A patient was a sustained ≥50% responder on a particular day if they completed the entire treatment period through day 84 and was a ≥50% responder (based on percent reduction in FS frequency from baseline) both on that day and every successive day until day 84 (end of treatment period). In the pooled efficacy population (N = 1,160), 15.5%, 18.1%, and 19.4% of patients taking BRV 50, 100, or 200 mg/day, respectively, achieved SRS on day 1 versus 6.7% for placebo (p < 0.001). Statistically significant SRS was also achieved for most of the BRV-treated groups in the three separate studies. This suggests that BRV has an early, sustained onset of action in a subset of responders. The incidence of adverse events during the first week was similar to that in the overall treatment period.


Assuntos
Anticonvulsivantes/uso terapêutico , Pirrolidinonas/uso terapêutico , Convulsões/tratamento farmacológico , Adulto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Fatores de Tempo , Resultado do Tratamento
5.
Epilepsia ; 57(7): 1139-51, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27265725

RESUMO

OBJECTIVES: To report pooled safety/tolerability and seizure outcome data from adults with uncontrolled partial-onset (focal) seizures (POS) receiving adjunctive brivaracetam (BRV) during phase IIb/III and long-term follow-up (LTFU) studies. METHODS: Seizure outcome data were pooled from phase IIb (NCT00175929 and NCT00175825), III/IIIb (NCT00490035, NCT00464269, NCT00504881, and NCT01261325) and associated LTFU studies (NCT00175916, NCT00150800, and NCT01339559). Safety/tolerability data were pooled from these studies plus NCT01405508, NCT01653262, and NCT01728077 (LTFU). Patients received placebo (during core studies) or BRV 5-200 mg/day. Safety/tolerability and seizure outcomes (BRV modal doses 50-200 mg/day) were assessed until January 17, 2014. RESULTS: Of 2,186 patients (97.3% with POS and 2.7% with other seizure types) who received BRV 50-200 mg/day, 2,051 (93.8%) completed core studies and continued in LTFU studies. Total BRV exposure: 5,339.4 patient-years (≥8.0 years in 41 patients); 6-, 12-, 24-, and 60-month retention: 91.0%, 79.8%, 68.1%, and 54.4%, respectively. Safety/tolerability data pooled from 2,186 patients: ≥1 treatment-emergent adverse event (TEAE) reported by 1,848 (84.5%) patients; 1,184 (54.2%) reported ≥1 TEAE considered treatment-related. Most frequent TEAEs (≥10%): headache (20.9%), dizziness (17.5%), somnolence (15.2%), nasopharyngitis (13.2%), fatigue (11.3%), and convulsion (10.6%). Serious TEAEs (SAEs) and treatment-related SAEs: 401 (18.3%) and 95 (4.3%) patients, respectively. Of 28 (1.3%) deaths, four (14.3%) were considered possibly treatment related by the investigator. Pooled seizure outcome data (1,836 patients): median POS frequency/28 days at baseline was 8.9; on treatment, median percentage reduction from baseline in POS/28 days was 48.8%, and ≥50% responder rate was 48.7%. Complete seizure freedom: 4.9%, 4.2%, 3.0%, and 3.3% for ≥6, 12, 24, and 60 months, respectively. Improvements were seen in health-related quality of life (HRQoL) from baseline, assessed by Quality of Life in Epilepsy Inventory-31. SIGNIFICANCE: Adjunctive BRV treatment in adults with POS was effective and generally well tolerated when administered long-term (≥8.0 years). Retention was high and HRQoL improvements were observed.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsias Parciais/tratamento farmacológico , Pirrolidinonas/uso terapêutico , Resultado do Tratamento , Adulto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
J Virol ; 88(14): 7715-26, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24807721

RESUMO

The RV144 ALVAC/AIDSVax HIV-1 vaccine clinical trial showed an estimated vaccine efficacy of 31.2%. Viral genetic analysis identified a vaccine-induced site of immune pressure in the HIV-1 envelope (Env) variable region 2 (V2) focused on residue 169, which is included in the epitope recognized by vaccinee-derived V2 monoclonal antibodies. The ALVAC/AIDSVax vaccine induced antibody-dependent cellular cytotoxicity (ADCC) against the Env V2 and constant 1 (C1) regions. In the presence of low IgA Env antibody levels, plasma levels of ADCC activity correlated with lower risk of infection. In this study, we demonstrate that C1 and V2 monoclonal antibodies isolated from RV144 vaccinees synergized for neutralization, infectious virus capture, and ADCC. Importantly, synergy increased the HIV-1 ADCC activity of V2 monoclonal antibody CH58 at concentrations similar to that observed in plasma of RV144 vaccinees. These findings raise the hypothesis that synergy among vaccine-induced antibodies with different epitope specificities contributes to HIV-1 antiviral antibody responses and is important to induce for reduction in the risk of HIV-1 transmission. Importance: The Thai RV144 ALVAC/AIDSVax prime-boost vaccine efficacy trial represents the only example of HIV-1 vaccine efficacy in humans to date. Studies aimed at identifying immune correlates involved in the modest vaccine-mediated protection identified HIV-1 envelope (Env) variable region 2-binding antibodies as inversely correlated with infection risk, and genetic analysis identified a site of immune pressure within the region recognized by these antibodies. Despite this evidence, the antiviral mechanisms by which variable region 2-specific antibodies may have contributed to lower rates of infection remain unclear. In this study, we demonstrate that vaccine-induced HIV-1 envelope variable region 2 and constant region 1 antibodies synergize for recognition of virus-infected cells, infectious virion capture, virus neutralization, and antibody-dependent cellular cytotoxicity. This is a major step in understanding how these types of antibodies may have cooperatively contributed to reducing infection risk and should be considered in the context of prospective vaccine design.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Anti-HIV/imunologia , Anticorpos Anti-HIV/isolamento & purificação , HIV-1/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Vacinas contra a AIDS/administração & dosagem , Humanos
7.
Epilepsia ; 56(12): 1890-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26471380

RESUMO

OBJECTIVE: Brivaracetam (BRV), a selective and high-affinity synaptic vesicle protein 2A ligand, is in development as adjunctive treatment for partial-onset (focal) seizures (POS). This phase 3 study (N01358; NCT01261325) aimed to confirm the efficacy and safety/tolerability of BRV in adults (≥ 16-80 years) with POS. METHODS: This randomized, double-blind, placebo-controlled, multicenter study enrolled patients with uncontrolled POS despite ongoing treatment with 1-2 antiepileptic drugs. Patients exposed to levetiracetam ≤ 90 days before visit 1 were excluded. Patients entered an 8-week prospective baseline period, followed by a 12-week treatment period when they were randomized 1:1:1 to placebo (PBO), BRV 100 mg/day, or BRV 200 mg/day, started without up-titration. The co-primary efficacy outcomes were percent reduction over placebo in 28-day adjusted POS frequency, and ≥ 50% responder rate based on percent reduction in POS frequency from baseline to the treatment period. RESULTS: Seven hundred sixty-eight patients were randomized; 760 were included in the efficacy analysis: 259, 252, and 249 in PBO, BRV 100 mg/day, and BRV 200 mg/day groups, respectively. Percent reduction over PBO in 28-day adjusted seizure frequency (95% confidence interval [CI]) was 22.8% for BRV 100 mg/day (13.3-31.2%; p < 0.001) and 23.2% for BRV 200 mg/day (13.8-31.6%; p < 0.001). The ≥ 50% responder rate (odds ratio vs. PBO; 95% CI) was 21.6% for PBO, 38.9% for BRV 100 mg/day (2.39; 1.6-3.6; p < 0.001), and 37.8% for BRV 200 mg/day (2.19; 1.5-3.3; p < 0.001). Treatment-emergent adverse events (TEAEs) occurred in 155 (59.4%) of 261 PBO patients versus 340 (67.6%) of 503 BRV-treated patients (safety population). Discontinuation rates due to TEAEs were 3.8%, 8.3%, and 6.8% for PBO, BRV 100 mg/day, and BRV 200 mg/day, respectively. Most frequent TEAEs (PBO versus BRV) were somnolence (7.7% vs. 18.1%), dizziness (5.0% vs. 12.3%), and fatigue (3.8% vs. 9.5%). SIGNIFICANCE: Adjunctive BRV 100 and 200 mg/day was efficacious in reducing POS in adults without concomitant levetiracetam use and was well tolerated.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsias Parciais/tratamento farmacológico , Pirrolidinonas/uso terapêutico , Adulto , Anticonvulsivantes/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Masculino , Pirrolidinonas/efeitos adversos , Resultado do Tratamento
8.
Blood ; 119(7): e35-44, 2012 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-22160618

RESUMO

B-cell chronic lymphocytic leukemia (B-CLL) is characterized by the clonal expansion of CD5-expressing B lymphocytes that produce mAbs often reactive with microbial or autoantigens. Long-term culture of B-CLL clones would permit the collection and characterization of B-CLL mAbs to study antigen specificity and of B-CLL DNA to investigate molecular mechanisms promoting the disease. However, the derivation of long-term cell lines (eg, by EBV), has not been efficient. We have improved the efficiency of EBV B-CLL transformation of CpG oligonucleotide-stimulated cells by incubating patient peripheral blood mononuclear cells in the presence of an irradiated mouse macrophage cell line, J774A.1. Using this approach, peripheral blood mononuclear cells isolated from 13 of 21 B-CLL patients were transformed as documented by IGHV-D-J sequencing. Four clones grew and retained CD5 expression in culture for 2 to 4 months. However, despite documentation of EBV infection by expression of EBNA2 and LMP1, B-CLL cells died after removal of macrophage feeder cells. Nevertheless, using electrofusion technology, we generated 6 stable hetero-hybridoma cell lines from EBV-transformed B-CLL cells, and these hetero-hybridomas produced immunoglobulin. Thus, we have established enhanced methods of B-CLL culture that will enable broader interrogation of B-CLL cells at the genetic and protein levels.


Assuntos
Processos de Crescimento Celular/fisiologia , Transformação Celular Viral , Células Alimentadoras/citologia , Herpesvirus Humano 4/fisiologia , Leucemia Linfocítica Crônica de Células B/patologia , Macrófagos/citologia , Animais , Linhagem Celular Transformada , Transformação Celular Viral/genética , Transformação Celular Viral/fisiologia , Células Cultivadas , Técnicas de Cocultura , Antígenos Nucleares do Vírus Epstein-Barr/genética , Células Alimentadoras/fisiologia , Herpesvirus Humano 4/genética , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Macrófagos/fisiologia , Camundongos , Regulação para Cima , Proteínas Virais/genética
9.
Blood Adv ; 8(10): 2552-2564, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38537079

RESUMO

ABSTRACT: Malaria is a highly oxidative parasitic disease in which anemia is the most common clinical symptom. A major contributor to the malarial anemia pathogenesis is the destruction of bystander, uninfected red blood cells (RBCs). Metabolic fluctuations are known to occur in the plasma of individuals with acute malaria, emphasizing the role of metabolic changes in disease progression and severity. Here, we report conditioned medium from Plasmodium falciparum culture induces oxidative stress in uninfected, catalase-depleted RBCs. As cell-permeable precursors to glutathione, we demonstrate the benefit of pre-exposure to exogenous glutamine, cysteine, and glycine amino acids for RBCs. Importantly, this pretreatment intrinsically prepares RBCs to mitigate oxidative stress.


Assuntos
Aminoácidos , Eritrócitos , Estresse Oxidativo , Plasmodium falciparum , Plasmodium falciparum/efeitos dos fármacos , Eritrócitos/parasitologia , Eritrócitos/metabolismo , Eritrócitos/efeitos dos fármacos , Humanos , Estresse Oxidativo/efeitos dos fármacos , Aminoácidos/metabolismo , Malária Falciparum/prevenção & controle , Malária Falciparum/parasitologia
10.
J Virol ; 86(14): 7496-507, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22553329

RESUMO

Most antibodies that broadly neutralize HIV-1 are highly somatically mutated in antibody clonal lineages that persist over time. Here, we describe the analysis of human antibodies induced during an HIV-1 vaccine trial (GSK PRO HIV-002) that used the clade B envelope (Env) gp120 of clone W6.1D (gp120(W6.1D)). Using dual-color antigen-specific sorting, we isolated Env-specific human monoclonal antibodies (MAbs) and studied the clonal persistence of antibodies in the setting of HIV-1 Env vaccination. We found evidence of V(H) somatic mutation induced by the vaccine but only to a modest level (3.8% ± 0.5%; range 0 to 8.2%). Analysis of 34 HIV-1-reactive MAbs recovered over four immunizations revealed evidence of both sequential recruitment of naïve B cells and restimulation of previously recruited memory B cells. These recombinant antibodies recapitulated the anti-HIV-1 activity of participant serum including pseudovirus neutralization and antibody-dependent cell-mediated cytotoxicity (ADCC). One antibody (3491) demonstrated a change in specificity following somatic mutation with binding of the inferred unmutated ancestor to a linear C2 peptide while the mutated antibody reacted only with a conformational epitope in gp120 Env. Thus, gp120(W6.1D) was strongly immunogenic but over four immunizations induced levels of affinity maturation below that of broadly neutralizing MAbs. Improved vaccination strategies will be needed to drive persistent stimulation of antibody clonal lineages to induce affinity maturation that results in highly mutated HIV-1 Env-reactive antibodies.


Assuntos
Vacinas contra a AIDS/imunologia , Afinidade de Anticorpos , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/imunologia , HIV-1/imunologia , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/genética , Anticorpos Neutralizantes/imunologia , Especificidade de Anticorpos , Citotoxicidade Celular Dependente de Anticorpos , Linfócitos B/imunologia , Anticorpos Anti-HIV/sangue , Anticorpos Anti-HIV/genética , Humanos , Esquemas de Imunização , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Memória Imunológica , Vacinas de Subunidades Antigênicas/imunologia
11.
J Virol ; 86(21): 11521-32, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22896626

RESUMO

The ALVAC-HIV/AIDSVAX-B/E RV144 vaccine trial showed an estimated efficacy of 31%. RV144 secondary immune correlate analysis demonstrated that the combination of low plasma anti-HIV-1 Env IgA antibodies and high levels of antibody-dependent cellular cytotoxicity (ADCC) inversely correlate with infection risk. One hypothesis is that the observed protection in RV144 is partially due to ADCC-mediating antibodies. We found that the majority (73 to 90%) of a representative group of vaccinees displayed plasma ADCC activity, usually (96.2%) blocked by competition with the C1 region-specific A32 Fab fragment. Using memory B-cell cultures and antigen-specific B-cell sorting, we isolated 23 ADCC-mediating nonclonally related antibodies from 6 vaccine recipients. These antibodies targeted A32-blockable conformational epitopes (n = 19), a non-A32-blockable conformational epitope (n = 1), and the gp120 Env variable loops (n = 3). Fourteen antibodies mediated cross-clade target cell killing. ADCC-mediating antibodies displayed modest levels of V-heavy (VH) chain somatic mutation (0.5 to 1.5%) and also displayed a disproportionate usage of VH1 family genes (74%), a phenomenon recently described for CD4-binding site broadly neutralizing antibodies (bNAbs). Maximal ADCC activity of VH1 antibodies correlated with mutation frequency. The polyclonality and low mutation frequency of these VH1 antibodies reveal fundamental differences in the regulation and maturation of these ADCC-mediating responses compared to VH1 bNAbs.


Assuntos
Vacinas contra a AIDS/imunologia , Citotoxicidade Celular Dependente de Anticorpos , Genes de Cadeia Pesada de Imunoglobulina , Anticorpos Anti-HIV/imunologia , HIV-1/imunologia , Vacinas contra a AIDS/administração & dosagem , Feminino , Experimentação Humana , Humanos , Masculino
12.
bioRxiv ; 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37292635

RESUMO

Malaria is a highly oxidative parasitic disease in which anemia is the most common clinical symptom. A major contributor to malarial anemia pathogenesis is the destruction of bystander, uninfected red blood cells. Metabolic fluctuations are known to occur in the plasma of individuals with acute malaria, emphasizing the role of metabolic changes in disease progression and severity. Here, we report that conditioned media from Plasmodium falciparum culture induces oxidative stress in healthy uninfected RBCs. Additionally, we show the benefit of amino acid pre-exposure for RBCs and how this pre-treatment intrinsically prepares RBCs to mitigate oxidative stress. Key points: Intracellular ROS is acquired in red blood cells incubated with Plasmodium falciparum conditioned media Glutamine, cysteine, and glycine amino acid supplementation increased glutathione biosynthesis and reduced ROS levels in stressed RBCs.

13.
J Virol ; 85(15): 7719-29, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21613396

RESUMO

The C3-V4 region is a major target of autologous neutralizing antibodies in HIV-1 subtype C infection. We previously identified a Center for AIDS Program of Research in South Africa (CAPRISA) participant, CAP88, who developed a potent neutralizing-antibody response within 3 months of infection that targeted an epitope in the C3 region of the HIV-1 envelope (P. L. Moore et al., PLoS Pathog. 5:e1000598, 2009). Here we showed that these type-specific antibodies could be adsorbed using recombinant gp120 from the transmitted/founder virus from CAP88 but not by gp120 made from other isolates. Furthermore, this activity could be depleted using a chimeric gp120 protein that contained only the C3 region from the CAP88 viral envelope engrafted onto the unrelated CAP63 viral envelope (called 63-88C3). On the basis of this, a differential sorting of memory B cells was performed using gp120s made from 63-88C3 and CAP63 labeled with different fluorochromes as positive and negative probes, respectively. This strategy resulted in the isolation of a highly specific monoclonal antibody (MAb), called CAP88-CH06, that neutralized the CAP88 transmitted/founder virus and viruses from acute infection but was unable to neutralize CAP88 viruses isolated at 6 and 12 months postinfection. The latter viruses contained 2 amino acid changes in the alpha-2 helix of C3 that mediated escape from this MAb. One of these changes involved the introduction of an N-linked glycan at position 339 that occluded the epitope, while the other mutation (either E343K or E350K) was a charge change. Our data validate the use of differential sorting to isolate a MAb targeting a specific epitope in the envelope glycoprotein and provided insights into the mechanisms of autologous neutralization escape.


Assuntos
Anticorpos Monoclonais/isolamento & purificação , Anticorpos Neutralizantes/imunologia , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/química , Linfócitos B/imunologia , Linhagem Celular , Ensaio de Imunoadsorção Enzimática , Epitopos/imunologia , HIV-1/imunologia , Humanos , Memória Imunológica , Modelos Moleculares
14.
J Virol ; 85(19): 9998-10009, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21795340

RESUMO

V2/V3 conformational epitope antibodies that broadly neutralize HIV-1 (PG9 and PG16) have been recently described. Since an elicitation of previously known broadly neutralizing antibodies has proven elusive, the induction of antibodies with such specificity is an important goal for HIV-1 vaccine development. A critical question is which immunogens and vaccine formulations might be used to trigger and drive the development of memory B cell precursors with V2/V3 conformational epitope specificity. In this paper we identified a clonal lineage of four V2/V3 conformational epitope broadly neutralizing antibodies (CH01 to CH04) from an African HIV-1-infected broad neutralizer and inferred their common reverted unmutated ancestor (RUA) antibodies. While conformational epitope antibodies rarely bind recombinant Env monomers, a screen of 32 recombinant envelopes for binding to the CH01 to CH04 antibodies showed monoclonal antibody (MAb) binding to the E.A244 gp120 Env and to chronic Env AE.CM243; MAbs CH01 and CH02 also bound to transmitted/founder Env B.9021. CH01 to CH04 neutralized 38% to 49% of a panel of 91 HIV-1 tier 2 pseudoviruses, while the RUAs neutralized only 16% of HIV-1 isolates. Although the reverted unmutated ancestors showed restricted neutralizing activity, they retained the ability to bind to the E.A244 gp120 HIV-1 envelope with an affinity predicted to trigger B cell development. Thus, E.A244, B.9021, and AE.CM243 Envs are three potential immunogen candidates for studies aimed at defining strategies to induce V2/V3 conformational epitope-specific antibodies.


Assuntos
Anticorpos Neutralizantes/imunologia , Epitopos/imunologia , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/imunologia , HIV-1/imunologia , Epitopos/genética , Feminino , Proteína gp120 do Envelope de HIV/genética , HIV-1/genética , Humanos , Testes de Neutralização , Ligação Proteica , Ressonância de Plasmônio de Superfície
15.
Curr Protoc ; 2(3): e400, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35349226

RESUMO

The bone microenvironment cellular composition plays an essential role in bone health and is disrupted in bone pathologies, such as osteoporosis, osteoarthritis, and cancer. Flow cytometry protocols for hematopoietic stem cell lineages are well defined and well established. Additionally, a consensus for mesenchymal stem cell flow markers has been developed. However, flow cytometry markers for bone-residing cells-osteoblasts, osteoclasts, and osteocytes-have not been proposed. Here, we describe a novel partial digestion method to separate these cells from the bone matrix and present new markers for enumerating these cells by flow cytometry. We optimized bone digestion and analyzed markers across murine, nonhuman primate, and human bone. The isolation and staining protocols can be used with either cell sorting or flow cytometry. Our method allows for the enumeration and collection of hematopoietic and mesenchymal lineage cells in the bone microenvironment combined with bone-residing stromal cells. Thus, we have established a multi-fluorochrome bone marrow cell-typing methodology. © 2022 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Partial digestion for murine long bone stromal cell isolation Alternate Protocol 1: Partial digestion for primate vertebrae stromal cell isolation Alternate Protocol 2: Murine vertebrae crushing for bone stromal cell isolation Basic Protocol 2: Staining of bone stromal cells Support Protocol 1: Fluorescence minus one control, isotype control, and antibody titration Basic Protocol 3: Cell sorting of bone stromal cells Alternate Protocol 3: Flow cytometry analysis of bone stromal cells Support Protocol 2: Preparing compensation beads.


Assuntos
Células da Medula Óssea , Células Estromais , Animais , Medula Óssea , Separação Celular/métodos , Citometria de Fluxo/métodos , Camundongos
16.
Mov Disord ; 26(1): 90-9, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21322021

RESUMO

In a multinational, double-blind, placebo-controlled trial (NCT00474058), 287 subjects with Parkinson's disease (PD) and unsatisfactory early-morning motor symptom control were randomized 2:1 to receive rotigotine (2-16 mg/24 hr [n = 190]) or placebo (n = 97). Treatment was titrated to optimal dose over 1-8 weeks with subsequent dose maintenance for 4 weeks. Early-morning motor function and nocturnal sleep disturbance were assessed as coprimary efficacy endpoints using the Unified Parkinson's Disease Rating Scale (UPDRS) Part III (Motor Examination) measured in the early morning prior to any medication intake and the modified Parkinson's Disease Sleep Scale (PDSS-2) (mean change from baseline to end of maintenance [EOM], last observation carried forward). At EOM, mean UPDRS Part III score had decreased by -7.0 points with rotigotine (from a baseline of 29.6 [standard deviation (SD) 12.3] and by -3.9 points with placebo (baseline 32.0 [13.3]). Mean PDSS-2 total score had decreased by -5.9 points with rotigotine (from a baseline of 19.3 [SD 9.3]) and by -1.9 points with placebo (baseline 20.5 [10.4]). This represented a significantly greater improvement with rotigotine compared with placebo on both the UPDRS Part III (treatment difference: -3.55 [95% confidence interval (CI) -5.37, -1.73]; P = 0.0002) and PDSS-2 (treatment difference: -4.26 [95% CI -6.08, -2.45]; P < 0.0001). The most frequently reported adverse events were nausea (placebo, 9%; rotigotine, 21%), application site reactions (placebo, 4%; rotigotine, 15%), and dizziness (placebo, 6%; rotigotine 10%). Twenty-four-hour transdermal delivery of rotigotine to PD patients with early-morning motor dysfunction resulted in significant benefits in control of both motor function and nocturnal sleep disturbances.


Assuntos
Agonistas de Dopamina/uso terapêutico , Atividade Motora/efeitos dos fármacos , Doença de Parkinson/complicações , Transtornos do Sono-Vigília/tratamento farmacológico , Tetra-Hidronaftalenos/uso terapêutico , Tiofenos/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Transtornos do Sono-Vigília/etiologia , Resultado do Tratamento
17.
BMC Neurol ; 11: 100, 2011 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-21831297

RESUMO

BACKGROUND: A recent trial involving predominantly Caucasian subjects with Parkinson Disease (PD) showed switching overnight from an oral dopaminergic agonist to the rotigotine patch was well tolerated without loss of efficacy. However, no such data have been generated for Korean patients. METHODS: This open-label multicenter trial investigated PD patients whose symptoms were not satisfactorily controlled by ropinirole, at a total daily dose of 3 mg to 12 mg, taken as monotherapy or as an adjunct to levodopa. Switching treatment from oral ropinirole to transdermal rotigotine was carried out overnight, with a dosage ratio of 1.5:1. After a 28-day treatment period, the safety and tolerability of switching was evaluated. Due to the exploratory nature of this trial, the effects of rotigotine on motor and nonmotor symptoms of PD were analyzed in a descriptive manner. RESULTS: Of the 116 subjects who received at least one treatment, 99 (85%) completed the 28-day trial period. Dose adjustments were required for 11 subjects who completed the treatment period. A total of 76 treatment-emergent adverse events (AEs) occurred in 45 subjects. No subject experienced a serious AE. Thirteen subjects discontinued rotigotine prematurely due to AEs. Efficacy results suggested improvements in both motor and nonmotor symptoms and quality of life after switching. Fifty-two subjects (46%) agreed that they preferred using the patch over oral medications, while 31 (28%) disagreed. CONCLUSIONS: Switching treatment overnight from oral ropinirole to transdermal rotigotine patch, using a dosage ratio of 1.5:1, was well tolerated in Korean patients with no loss of efficacy. TRIAL REGISTRATION: This trial is registered with the ClincalTrails.gov Registry (NCT00593606).


Assuntos
Antiparkinsonianos/administração & dosagem , Indóis/administração & dosagem , Doença de Parkinson/tratamento farmacológico , Administração Cutânea , Administração Oral , Antiparkinsonianos/efeitos adversos , Antiparkinsonianos/farmacocinética , Esquema de Medicação , Feminino , Humanos , Indóis/efeitos adversos , Indóis/farmacocinética , Masculino , Pessoa de Meia-Idade
18.
Appl Microbiol Biotechnol ; 90(5): 1773-83, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21538116

RESUMO

A wide range of techniques, including high-throughput DNA sequencing methods, have been applied to the evaluation of the normal intestinal flora. However, the inability to grow many of those species in culture imposes substantial constraints on the techniques used to evaluate this important community. The presence of biofilms in the normal gut adds further complexity to the issue. In this study, a flow cytometric analysis was used to separate intact bacterial cells, cell debris, and other particulate matter based on bacteria-specific staining and particle size. In addition, an analysis of biofilm formation using fluorescent light microscopy was conducted. Using these approaches, the ratio of bacterial cell debris to intact bacterial cells as a measure of spontaneous lysis of bacterial cells in the gut of the Cape dune mole-rat (Bathyergus suillus) and the laboratory rabbit (Oryctolagus cuniculus) was examined, and the degree of biofilm formation was semi-quantitatively assessed. The results suggest that the degree of spontaneous cell lysis was greater in the appendix than in the cecum in both the mole-rat and the rabbit. Further, the results point toward extensive epithelial-associated biofilm formation in the proximal mole-rat and rabbit large bowel, although the biofilms may be less structured than those found in laboratory rodents and in humans.


Assuntos
Bacteriólise , Biofilmes , Colo/microbiologia , Animais , Bactérias/citologia , Ratos-Toupeira , Coelhos , Ratos
19.
Appl Environ Microbiol ; 76(14): 4655-63, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20472724

RESUMO

Although mice associated with a single bacterial species have been used to provide a simple model for analysis of host-bacteria relationships, bacteria have been shown to display adaptability when grown in a variety of novel environments. In this study, changes associated with the host-bacterium relationship in mice monoassociated with Escherichia coli K-12 over a period of 1,031 days were evaluated. After 80 days, phenotypic diversification of E. coli was observed, with the colonizing bacteria having a broader distribution of growth rates in the laboratory than the parent E. coli. After 1,031 days, which included three generations of mice and an estimated 20,000 generations of E. coli, the initially homogeneous bacteria colonizing the mice had evolved to have widely different growth rates on agar, a potential decrease in tendency for spontaneous lysis in vivo, and an increased tendency for spontaneous lysis in vitro. Importantly, mice at the end of the experiment were colonized at an average density of bacteria that was more than 3-fold greater than mice colonized on day 80. Evaluation of selected isolates on day 1,031 revealed unique restriction endonuclease patterns and differences between isolates in expression of more than 10% of the proteins identified by two-dimensional electrophoresis, suggesting complex changes underlying the evolution of diversity during the experiment. These results suggest that monoassociated mice might be used as a tool for characterizing niches occupied by the intestinal flora and potentially as a method of targeting the evolution of bacteria for applications in biotechnology.


Assuntos
Escherichia coli K12/crescimento & desenvolvimento , Trato Gastrointestinal/microbiologia , Animais , Escherichia coli K12/genética , Estudos Longitudinais , Camundongos , Mapeamento por Restrição
20.
Stem Cells ; 27(3): 612-22, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19056905

RESUMO

Bronchiolar stem cells have been functionally defined in vivo on the basis of their resistance to chemical (naphthalene) injury, their infrequent proliferation relative to other progenitor cell types, and their coexpression of the airway and alveolar secretory cell markers Clara cell secretory protein and pro-surfactant protein C, respectively. Cell surface markers that have previously been used for their prospective isolation included Sca-1 and CD34. Using transgenic animal models associated with stem cell expansion, ablation, and lineage tracing, we demonstrate that CD34(pos) cells do not belong to the airway epithelial lineage and that cell surface Sca-1 immunoreactivity does not distinguish between bronchiolar stem and facultative transit-amplifying (Clara) cell populations. Furthermore, we show that high autofluorescence (AF(high)) is a distinguishing characteristic of Clara cells allowing for the fractionation of AF(low) bronchiolar stem cells. On the basis of these data we show that the defining phenotype of the bronchiolar stem cell is CD45(neg) CD31(neg) CD34(neg) Sca-l(low) AF(low). This refinement in the definition of bronchiolar stem cells provides a critical tool by which to assess functional and molecular distinctions between bronchiolar stem cells and the more abundant pool of facultative transit-amplifying (Clara) cells.


Assuntos
Bronquíolos/citologia , Fluorescência , Imunofenotipagem/métodos , Células-Tronco/citologia , Células-Tronco/metabolismo , Animais , Antígenos CD34/metabolismo , Antígenos Ly/metabolismo , Células Cultivadas , Citometria de Fluxo , Imunofluorescência , Antígenos Comuns de Leucócito/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Reação em Cadeia da Polimerase
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