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1.
Cancers (Basel) ; 15(17)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37686579

RESUMO

BACKGROUND: Oncolytic viruses (OVs) have been utilized since 1990s for targeted cancer treatment. Our study examined the Measles-Mumps-Rubella (MMR) vaccine's cancer-killing potency against Glioblastoma (GBM), a therapy-resistant, aggressive cancer type. METHODOLOGY: We used GBM cell lines, primary GBM cells, and normal mice microglial cells, to assess the MMR vaccine's efficacy through cell viability, cell cycle analysis, intracellular viral load via RT-PCR, and Transmission Electron Microscopy (TEM). RESULTS: After 72 h of MMR treatment, GBM cell lines and primary GBM cells exhibited significant viability reduction compared to untreated cells. Conversely, normal microglial cells showed only minor changes in viability and morphology. Intracellular viral load tests indicated GBM cells' increased sensitivity to MMR viruses compared to normal cells. The cell cycle study also revealed measles and mumps viruses' crucial role in cytopathic effects, with the rubella virus causing cell cycle arrest. CONCLUSION: Herein the reported results demonstrate the anti-cancer activity of the MMR vaccine against GBM cells. Accordingly, the MMR vaccine warrants further study as a potential new tool for GBM therapy and relapse prevention. Therapeutic potential of the MMR vaccine has been found to be promising in earlier studies as well.

2.
EMBO J ; 41(3): e108518, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34957576

RESUMO

Antibodies of the immunoglobulin M (IgM) class represent the frontline of humoral immune responses. They are secreted as planar polymers in which flanking µ2 L2 "monomeric" subunits are linked by two disulfide bonds, one formed by the penultimate cysteine (C575) in the tailpiece of secretory µ chains (µs tp) and the second by C414 in the Cµ3. The latter bond is not present in membrane IgM. Here, we show that C575 forms a non-native, intra-subunit disulfide bond as a key step in the biogenesis of secretory IgM. The abundance of this unexpected intermediate correlates with the onset and extent of polymerization. The rearrangement of the C-terminal tails into a native quaternary structure is guaranteed by the engagement of protein disulfide isomerase ERp44, which attacks the non-native C575 bonds. The resulting conformational changes promote polymerization and formation of C414 disulfide linkages. This unusual assembly pathway allows secretory polymers to form without the risk of disturbing the role of membrane IgM as part of the B cell antigen receptor.


Assuntos
Dissulfetos/química , Imunoglobulina M/metabolismo , Proteínas de Membrana/metabolismo , Chaperonas Moleculares/metabolismo , Células HEK293 , Humanos , Imunoglobulina M/química
3.
Front Med (Lausanne) ; 9: 1062450, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36698815

RESUMO

COVID-19 in immunocompromised patients is difficult to treat. SARS-CoV-2 interaction with the host immune system and the role of therapy still remains only partly understood. There are no data regarding the use of monoclonal antibodies and the combination of two antivirals in fighting viral replication and disease progression. We report the cases of two patients, both treated with rituximab for non-Hodgkin lymphoma and granulomatosis with polyangiitis, respectively, and both hospitalized for COVID-19 with positive SARS-CoV-2 RNAemia, who were successfully treated with a salvage combination therapy with sotrovimab, remdesivir and nirmatrelvir/ritonavir.

4.
J Med Case Rep ; 15(1): 589, 2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34903275

RESUMO

BACKGROUND: Parsonage-Turner syndrome is an acute peripheral neuropathy that affects the upper brachial plexus region. Previously published reports demonstrate that the condition can be triggered by surgery, infection, autoimmune diseases, strenuous exercise, trauma, radiation, and vaccination. Parsonage-Turner syndrome has already been reported in three other patients who were vaccinated against coronavirus disease 2019. CASE PRESENTATION: We report the case of a 51-year-old Caucasian man without comorbidities who received the first dose of the ChAdOx1-S recombinant vaccine (Vaxzevria, AstraZeneca, Oxford, UK) against coronavirus disease 2019 and was diagnosed with Parsonage-Turner syndrome. A few days after getting vaccinated, the patient reported a progressive increase in pain in the region of vaccine administration. One month later, the shoulder pain was followed by symptoms of hypoesthesia and muscle weakness on abduction and elevation of the left upper limb. Neurological examination revealed an atrophy of the proximal muscles of the left upper limb, accompanied by paresis of the left deltoid, biceps brachii, triceps brachii, and infraspinatus muscles. Electroneuromyography carried out 3 months after the onset of symptoms showed signs consistent with brachial plexus neuritis. The adverse reaction has been properly reported to the Italian Pharmacovigilance System (Italian Medicines Agency-Agenzia Italiana del Farmaco. CONCLUSION: The increased awareness of such association is essential for early identification and diagnosis and, thus, better clinical outcomes.


Assuntos
Neurite do Plexo Braquial , COVID-19 , Vacinas , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Vacinação
5.
Vaccines (Basel) ; 9(12)2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34960174

RESUMO

Systemic sclerosis (SSc) is a rare autoimmune inflammatory rheumatic disease. The prevalence of SSc ranges from 7 to 700 cases per million worldwide. Due to multiple organ involvement and constant inflammatory state, this group of patients presents an increased risk of infectious diseases. This paper aimed to gather the up-to-date evidence on vaccination strategies for patients with SSc and to be a useful tool for the prevention and management of infectious diseases. The authors conducted a scoping review in which each paragraph presents data on a specific vaccine's safety, immunogenicity, and efficacy. The work deals with the following topics: SARS-CoV-2, seasonal influenza, S. pneumoniae, HAV, HBV, HZV, N. meningitidis, H. influenzae, HPV, and diphtheria-tetanus-pertussis.

6.
Open Forum Infect Dis ; 8(11): ofab217, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34796242

RESUMO

BACKGROUND: Immunocompromised patients show prolonged shedding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in nasopharyngeal swabs. We report a case of prolonged persistence of viable SARS-CoV-2 associated with clinical relapses of coronavirus disease 2019 (COVID-19) in a patient with mantle cell lymphoma who underwent treatment with rituximab, bendamustine, cytarabine with consequent lymphopenia and hypogammaglobulinemia. METHODS: Nasopharyngeal swabs and blood samples were tested for SARS-CoV-2 by real-time polymerase chain reaction (RT-PCR). On 5 positive nasopharyngeal swabs, we performed viral culture and next-generation sequencing. We analyzed the patient's adaptive and innate immunity to characterize T- and NK-cell subsets. RESULTS: SARS-CoV-2 RT-PCR on nasopharyngeal swabs samples remained positive for 268 days. All 5 performed viral cultures were positive, and genomic analysis confirmed a persistent infection with the same strain. Viremia resulted positive in 3 out of 4 COVID-19 clinical relapses and cleared each time after remdesivir treatment. The T- and NK-cell dynamic was different in aviremic and viremic samples, and no SARS-CoV-2-specific antibodies were detected throughout the disease course. CONCLUSIONS: In our patient, SARS-CoV-2 persisted with proven infectivity for >8 months. Viremia was associated with COVID-19 relapses, and remdesivir treatment was effective in viremia clearance and symptom remission, although it was unable to clear the virus from the upper respiratory airways. During the viremic phase, we observed a low frequency of terminal effector CD8+ T lymphocytes in peripheral blood; these are probably recruited in inflammatory tissue for viral eradication. In addition, we found a high level of NK-cell repertoire perturbation with relevant involvement during SARS-CoV-2 viremia.

7.
BMC Infect Dis ; 21(1): 353, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33858331

RESUMO

BACKGROUND: The primary objective of the study is to describe the cellular characteristics of bronchoalveolar lavage fluid (BALF) of COVID-19 patients requiring invasive mechanical ventilation; the secondary outcome is to describe BALF findings between survivors vs non-survivors. MATERIALS AND METHODS: Patients positive for SARS-CoV-2 RT PCR, admitted to ICU between March and April 2020 were enrolled. At ICU admission, BALF were analyzed by flow cytometry. Univariate, multivariate and Spearman correlation analyses were performed. RESULTS: Sixty-four patients were enrolled, median age of 64 years (IQR 58-69). The majority cells in the BALF were neutrophils (70%, IQR 37.5-90.5) and macrophages (27%, IQR 7-49) while a minority were lymphocytes, 1%, TCD3+ 92% (IQR 82-95). The ICU mortality was 32.8%. Non-survivors had a significantly older age (p = 0.033) and peripheral lymphocytes (p = 0.012) were lower compared to the survivors. At multivariate analysis the percentage of macrophages in the BALF correlated with poor outcome (OR 1.336, CI95% 1.014-1.759, p = 0.039). CONCLUSIONS: In critically ill patients, BALF cellularity is mainly composed of neutrophils and macrophages. The macrophages percentage in the BALF at ICU admittance correlated with higher ICU mortality. The lack of lymphocytes in BALF could partly explain a reduced anti-viral response.


Assuntos
Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , COVID-19/epidemiologia , COVID-19/imunologia , Contagem de Leucócitos , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Respiração Artificial , Adulto , Idoso , Líquido da Lavagem Broncoalveolar/virologia , COVID-19/mortalidade , COVID-19/virologia , Estado Terminal/epidemiologia , Feminino , Humanos , Unidades de Terapia Intensiva , Itália/epidemiologia , Linfócitos/citologia , Macrófagos/citologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/citologia , Pneumonia Viral/mortalidade , Pneumonia Viral/virologia , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Sobreviventes/estatística & dados numéricos , Resultado do Tratamento
8.
J Prev Med Hyg ; 62(4): E864-E870, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35603234

RESUMO

Background: We conducted a population-based cohort study to estimate mortality before, during and after the COVID-19 peak and to compare mortality in 2020 with rates reported in previous years, with a view to helping decision makers to apply containment measures for high-risk groups. Methods: All deaths were collected between 2015 and 2020 from municipal registry database. In 2020, weeks 1-26 were stratified in three periods: before, during and after the COVID mortality peak. The Poisson Generalized Linear regression Model showed the "harvesting effect". Three logistic regressions for 8 dependent variables (age and comorbidities) and a t-test of differences described all-cause mortality risk factors in 2019 and 2020 and differences between COVID and non-COVID patients. Results: A total of 47,876 deaths were collected. All-cause deaths increased by 38.5% during the COVID peak and decreased by 18% during the post-peak period in comparison with the average registered during the control period (2015-19), with significant mortality displacement in 2020. Except for chronic renal injuries in subjects aged 45-64 years, diabetes and chronic cardiovascular diseases in those aged 65-84 years, and neuropathies in those aged > 84 years, the weight of comorbidities in deaths was similar or lower in COVID subjects than in non-COVID subjects. Discussions: Surprisingly, the weight of comorbidities in death, compared to weight in non-COVID subjects allows you to highlight some surprising results such as COPD, IBD and Cancer. The excess mortality that we observed in the entire period were modest in comparison with initial estimates during the peak, owing to the mild influenza season and the harvesting effect starting from the second half of May.


Assuntos
COVID-19 , Estudos de Coortes , Humanos , Pandemias , Fatores de Risco , SARS-CoV-2
9.
J Obstet Gynaecol Res ; 46(7): 989-1006, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32390320

RESUMO

AIM: Human papillomavirus (HPV) is the etiologic agent of the majority of cervical intraepithelial lesions (CIN) and cervical cancers. While prophylactic HPV vaccines prevent infections from the main high-risk HPV types associated with cervical cancer, alternative nonsurgical and nonablative therapeutics to treat HPV infection and preinvasive HPV diseases have been experimentally investigated. Therapeutic vaccines are an emerging investigational strategy. This review aims to introduce the results of the main clinical trials on the use of therapeutic vaccines for treating HPV infection and -related CIN, reporting the ongoing studies on this field. METHODS: Data research was conducted using MEDLINE, EMBASE, Web of Sciences, Scopus, ClinicalTrial.gov, OVID and Cochrane Library querying for all articles related to therapeutic vaccines for the treatment of HPV-related CIN. Selection criteria included randomized clinical trials, nonrandomized controlled studies and review articles. RESULTS: Preliminary data are available on the evaluation of therapeutic vaccines for treating cervical HPV infections and CIN. Despite having in vitro demonstrated to obtain humoral and cytotoxic responses, therapeutic vaccines have not yet clinically demonstrated consistent success; moreover, each class of therapeutic vaccines has advantages and limitations. Early clinical data are available in the literature for these compounds, except for MVA E2, which reached the phase III clinical trial status, obtaining positive clinical outcomes. CONCLUSION: Despite promising results, to date many obstacles are still present before hypothesize an introduction in the clinical practice within the next years. Further studies will draw a definitive conclusion on the role of therapeutic vaccines in this setting.


Assuntos
Alphapapillomavirus , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Feminino , Humanos , Papillomaviridae , Infecções por Papillomavirus/prevenção & controle , Neoplasias do Colo do Útero/prevenção & controle , Displasia do Colo do Útero/prevenção & controle
10.
BMC Health Serv Res ; 19(1): 585, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31426795

RESUMO

BACKGROUND: Influenza-like illnesses (ILIs) and lower respiratory tract infections (LRTIs) cause substantial morbidity and mortality worldwide. The study assessed the health and economic burden of ILI and LRTI according to age and comorbidities, since available evidence is limited and heterogeneous. METHOD: The prevalence of comorbidities, the seasonal incidence rates and the mean and per capita direct costs of ED accesses for ILI/LRTI, whether followed by hospitalization or not, recorded in adults aged ≥50 years over the last 6 years, in the referral hospitals located in the Genoese metropolitan area (Liguria, Italy) where the syndromic surveillance system is active, were evaluated through a retrospective observational study. Comorbidities were estimated through the Chronic Condition Data Warehouse that integrates multiple Medicare data sources. A comparison with the administrative healthcare International Classification of Diseases-9th revision-Clinical Modification (ICD-9-CM)-based data was also conducted. RESULTS: The prevalence of subjects with ≥1 comorbidity ranged from 23.49 to 59.92%. The most prevalent all-age comorbidities were cardiovascular diseases and cancer. The overall ILI/LRTI incidence rate was 6.73/1000 person-years, almost double the value derived from routine data, and increased with age. The highest rates were observed in patients with renal failure and bronchopneumopathies. The mean cost of ED accesses/hospitalization for ILI/LRTI was €3353 and was almost twice as high in the ≥85 years as in the youngest age-group. The highest mean costs were observed in patients with renal failure and cancer. The per capita costs increased from €4 to €71 with age, and were highest in patients with renal failure and bronchopneumopathy. CONCLUSION: The burden of ILIs/LRTIs in terms of ED accesses and hospitalizations in adults aged ≥50 years is heavy, and is related to increasing age and, especially, to specific comorbidities. These results could contribute to revising age- and risk-based anti-influenza and -pneumococcus immunization strategies.


Assuntos
Efeitos Psicossociais da Doença , Influenza Humana/economia , Infecções Respiratórias/economia , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Feminino , Hospitalização/economia , Hospitalização/estatística & dados numéricos , Humanos , Imunização , Vacinas contra Influenza , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Morbidade , Prevalência , Encaminhamento e Consulta/estatística & dados numéricos , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/prevenção & controle , Estudos Retrospectivos , Vigilância de Evento Sentinela , Vacinação/economia , Vacinação/estatística & dados numéricos
11.
Expert Opin Biol Ther ; 19(7): 671-683, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30957589

RESUMO

INTRODUCTION: Influenza occurs worldwide and causes significant disease burden in terms of morbidity, associated complications, hospitalizations, and deaths. Vaccination constitutes the primary approach for controlling influenza. Current influenza vaccines elicit a strain-specific response yet occasionally exhibit suboptimal effectiveness. This review describes the limits of available immunization tools and the future prospects and potentiality of universal influenza vaccines. AREAS COVERED: New 'universal' vaccines, which are presently under development, are expected to overcome the problems related to the high variability of influenza viruses, such as the need for seasonal vaccine updates and re-vaccination. Here, we explore vaccines based on the highly conserved epitopes of the HA, NA, or extracellular domain of the influenza M2 protein, along with those based on the internal proteins such as NP and M1. EXPERT OPINION: The development of a universal influenza vaccine that confers protection against homologous, drifted, and shifted influenza virus strains could obviate the need for annual reformulation and mitigate disease burden. The scientific community has long been awaiting the advent of universal influenza vaccines; these are currently under development in laboratories worldwide. If such vaccines are immunogenic, efficacious, and able to confer long-lasting immunity, they might be integrated with or supplant traditional influenza vaccines.


Assuntos
Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Animais , Hemaglutininas/imunologia , Humanos , Influenza Humana/imunologia , Neuraminidase/imunologia , Peptídeos/imunologia , RNA Mensageiro/imunologia , RNA Mensageiro/metabolismo , Linfócitos T/imunologia , Proteínas da Matriz Viral/imunologia
12.
Elife ; 82019 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-30869076

RESUMO

How endoplasmic reticulum (ER) stress leads to cytotoxicity is ill-defined. Previously we showed that HeLa cells readjust homeostasis upon proteostatically driven ER stress, triggered by inducible bulk expression of secretory immunoglobulin M heavy chain (µs) thanks to the unfolded protein response (UPR; Bakunts et al., 2017). Here we show that conditions that prevent that an excess of the ER resident chaperone (and UPR target gene) BiP over µs is restored lead to µs-driven proteotoxicity, i.e. abrogation of HRD1-mediated ER-associated degradation (ERAD), or of the UPR, in particular the ATF6α branch. Such conditions are tolerated instead upon removal of the BiP-sequestering first constant domain (CH1) from µs. Thus, our data define proteostatic ER stress to be a specific consequence of inadequate BiP availability, which both the UPR and ERAD redeem.


Assuntos
Estresse do Retículo Endoplasmático , Células Epiteliais/fisiologia , Proteínas de Choque Térmico/metabolismo , Chaperona BiP do Retículo Endoplasmático , Degradação Associada com o Retículo Endoplasmático , Células HeLa , Humanos , Proteostase , Resposta a Proteínas não Dobradas
13.
Sci Adv ; 4(5): eaar5770, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29732408

RESUMO

Upon engagement of tyrosine kinase receptors, nicotinamide adenine dinucleotide phosphate (NADPH)-oxidases release H2O2 in the extracellular space. We reported previously that aquaporin-8 (AQP8) transports H2O2 across the plasma membrane and is reversibly gated during cell stress, modulating signal strength and duration. We show that AQP8 gating is mediated by persulfidation of cysteine 53 (C53). Treatment with H2S is sufficient to block H2O2 entry in unstressed cells. Silencing cystathionine ß-synthase (CBS) prevents closure, suggesting that this enzyme is the main source of H2S. Molecular modeling indicates that C53 persulfidation displaces a nearby histidine located in the narrowest part of the channel. We propose that H2O2 molecules transported through AQP8 sulfenylate C53, making it susceptible to H2S produced by CBS. This mechanism tunes H2O2 transport and may control signaling and limit oxidative stress.


Assuntos
Aquaporinas/metabolismo , Sulfetos/metabolismo , Sequência de Aminoácidos , Aquaporinas/química , Transporte Biológico , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular , Peróxido de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/metabolismo , Modelos Biológicos , Conformação Molecular , Oxirredução , Estresse Fisiológico , Sulfetos/química
14.
Elife ; 62017 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-29251598

RESUMO

Insufficient folding capacity of the endoplasmic reticulum (ER) activates the unfolded protein response (UPR) to restore homeostasis. Yet, how the UPR achieves ER homeostatic readjustment is poorly investigated, as in most studies the ER stress that is elicited cannot be overcome. Here we show that a proteostatic insult, provoked by persistent expression of the secretory heavy chain of immunoglobulin M (µs), is well-tolerated in HeLa cells. Upon µs expression, its levels temporarily eclipse those of the ER chaperone BiP, leading to acute, full-geared UPR activation. Once BiP is in excess again, the UPR transitions to chronic, submaximal activation, indicating that the UPR senses ER stress in a ratiometric fashion. In this process, the ER expands about three-fold and becomes dominated by BiP. As the UPR is essential for successful ER homeostatic readjustment in the HeLa-µs model, it provides an ideal system for dissecting the intricacies of how the UPR evaluates and alleviates ER stress.


Assuntos
Proteínas de Choque Térmico/metabolismo , Imunoglobulina M/metabolismo , Transdução de Sinais , Resposta a Proteínas não Dobradas , Chaperona BiP do Retículo Endoplasmático , Células Epiteliais/metabolismo , Células HeLa , Humanos
15.
J Cell Sci ; 130(19): 3222-3233, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28794014

RESUMO

The unfolded protein response (UPR) allows cells to adjust secretory pathway capacity according to need. Ire1, the endoplasmic reticulum (ER) stress sensor and central activator of the UPR is conserved from the budding yeast Saccharomyces cerevisiae to humans. Under ER stress conditions, Ire1 clusters into foci that enable optimal UPR activation. To discover factors that affect Ire1 clustering, we performed a high-content screen using a whole-genome yeast mutant library expressing Ire1-mCherry. We imaged the strains following UPR induction and found 154 strains that displayed alterations in Ire1 clustering. The hits were enriched for iron and heme effectors and binding proteins. By performing pharmacological depletion and repletion, we confirmed that iron (Fe3+) affects UPR activation in both yeast and human cells. We suggest that Ire1 clustering propensity depends on membrane composition, which is governed by heme-dependent biosynthesis of sterols. Our findings highlight the diverse cellular functions that feed into the UPR and emphasize the cross-talk between organelles required to concertedly maintain homeostasis.


Assuntos
Estresse do Retículo Endoplasmático/fisiologia , Ferro/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Transdução de Sinais/fisiologia , Resposta a Proteínas não Dobradas/fisiologia , Glicoproteínas de Membrana/genética , Proteínas Serina-Treonina Quinases/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
16.
Blood ; 129(15): 2132-2142, 2017 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-28130214

RESUMO

Systemic light chain (AL) amyloidosis is caused by the clonal production of an unstable immunoglobulin light chain (LC), which affects organ function systemically. Although pathogenic LCs have been characterized biochemically, little is known about the biology of amyloidogenic plasma cells (PCs). Intrigued by the unique response rates of AL amyloidosis patients to the first-in-class proteasome inhibitor (PI) bortezomib, we purified and investigated patient-derived AL PCs, in comparison with primary multiple myeloma (MM) PCs, the prototypical PI-responsive cells. Functional, biochemical, and morphological characterization revealed an unprecedented intrinsic sensitivity of AL PCs to PIs, even higher than that of MM PCs, associated with distinctive organellar features and expression patterns indicative of cellular stress. These consisted of expanded endoplasmic reticulum (ER), perinuclear mitochondria, and a higher abundance of stress-related transcripts, and were consistent with reduced autophagic control of organelle homeostasis. To test whether PI sensitivity stems from AL LC production, we engineered PC lines that can be induced to express amyloidogenic and nonamyloidogenic LCs, and found that AL LC expression alters cell growth and proteostasis and confers PI sensitivity. Our study discloses amyloidogenic LC production as an intrinsic PC stressor, and identifies stress-responsive pathways as novel potential therapeutic targets. Moreover, we contribute a cellular disease model to dissect the biology of AL PCs.


Assuntos
Amiloidose/tratamento farmacológico , Amiloidose/metabolismo , Bortezomib/farmacocinética , Cadeias Leves de Imunoglobulina/biossíntese , Plasmócitos/metabolismo , Inibidores de Proteassoma/farmacocinética , Amiloidose/patologia , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/patologia , Feminino , Humanos , Masculino , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Plasmócitos/patologia
17.
Ann Hematol ; 93(4): 669-76, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24097084

RESUMO

Viral respiratory tract infections (VRTI) are an important cause of morbidity and mortality in haematology patients, particularly after haematopoietic stem cell transplantation (HSCT). The incidence, clinical presentation and outcome of symptomatic and asymptomatic VRTI in HSCT outpatient unit were prospectively evaluated during a single influenza season (January-March 2011). Pharyngeal swabs were performed at the first visit and if new symptoms were present. Molecular multiplex assay for 12 respiratory viruses was performed by the regional reference laboratory. Among 264 swabs from 193 outpatients, 58 (22 %) resulted positive for 61 viruses (influenza, n = 20; respiratory syncytial virus [RSV], n = 21; rhinovirus, n = 12; coronavirus, n = 4; adenovirus, n = 3; parainfluenza, n = 1). VRTI were detected more frequently in the presence of symptoms than in asymptomatic patients: 49 out of 162 (30 %) vs. 9 out of 102 (9 %), p < 0.001. Influenza-like illness syndrome (ILI) was significantly associated with a VRTI if compared to other presentations (42 %), while the European Centre for Disease Prevention and Control definition was not (30 %). Positive predictive value (PPV) of ILI for influenza was 17 %. Influenza and RSV peak periods were contemporary. Influenza prophylaxis was given to 25 patients following exposure. Low rate of progression from upper to lower respiratory tract infection (approximately 5 % for influenza and RSV), no nosocomial epidemics and no VRTI-related deaths were observed. VRTI are very frequent in high-risk haematology outpatients, but symptoms are aspecific and PPV of ILI is low. Symptoms of influenza and RSV overlap. Thus, microbiological diagnosis and contact preventive measures are crucial. Rather than universal influenza prophylaxis, prompt diagnosis and treatment of only documented infections could be pursued.


Assuntos
Assistência Ambulatorial/métodos , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/epidemiologia , Transplante de Células-Tronco Hematopoéticas , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Estudos de Coortes , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/terapia , Feminino , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Influenza Humana/terapia , Masculino , Estudos Prospectivos , Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/terapia , Rhinovirus/isolamento & purificação
19.
IUBMB Life ; 62(7): 503-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20552641

RESUMO

Macroautophagy, here called autophagy, is literally a "self-eating" catabolic process, which is evolutionarily conserved. Autophagy is initiated by cellular stress pathways, resulting in the sequestration or engulfment of cytosolic proteins, membranes, and organelles in a double membrane structure that fuses with endosomes and lysosomes, thus delivering the sequestered material for degradation. Autophagy is implicated in a number of human diseases, many of which can either be characterized by an imbalance in protein, organelle, or cellular homeostasis, ultimately resulting in an alteration of the autophagic response. Here, we will review the recent progress made in understanding the induction of autophagy, with emphasis on the contributions from our laboratory.


Assuntos
Autofagia/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Proteína Homóloga à Proteína-1 Relacionada à Autofagia , Proteínas Relacionadas à Autofagia , Proteínas de Transporte/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Alvo Mecanístico do Complexo 1 de Rapamicina , Proteínas de Membrana/fisiologia , Modelos Biológicos , Complexos Multiproteicos , Fagossomos/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Fosfatos de Fosfatidilinositol/metabolismo , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/fisiologia , Serina-Treonina Quinases TOR , Fatores de Transcrição/fisiologia
20.
Blood ; 113(13): 3040-9, 2009 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-19164601

RESUMO

Proteasome inhibitors (PIs) are effective against multiple myeloma (MM), but the mechanisms of action and bases of individual susceptibility remain unclear. Recent work linked PI sensitivity to protein synthesis and proteasome activity, raising the question whether different levels of proteasome expression and workload underlie PI sensitivity in MM cells (MMCs). Exploiting human MM lines characterized by differential PI sensitivity, we report that highly sensitive MMCs express lower proteasome levels and higher proteasomal workload than relatively PI-resistant MMCs, resulting in the accumulation of polyubiquitinated proteins at the expense of free ubiquitin (proteasome stress). Manipulating proteasome expression or workload alters apoptotic sensitivity to PI, demonstrating a cause-effect relationship between proteasome stress and apoptotic responses in MMCs. Intracellular immunostaining in primary, patient-derived MMCs reveals that polyubiquitinated proteins hallmark neoplastic plasma cells, in positive correlation with immunoglobulin (Ig) content, both intra- and interpatient. Moreover, overall proteasome activity of primary MMCs inversely correlates with apoptotic sensitivity to PI. Altogether, our data indicate that the balance between proteasome workload and degradative capacity represents a critical determinant of apoptotic sensitivity of MMCs to PI, potentially providing a framework for identifying indicators of responsiveness and designing novel combination therapies.


Assuntos
Apoptose/efeitos dos fármacos , Inibidores de Cisteína Proteinase/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/fisiologia , Mieloma Múltiplo/tratamento farmacológico , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Linfócitos B/patologia , Diferenciação Celular/efeitos dos fármacos , Inibidores de Cisteína Proteinase/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Células HeLa , Humanos , Leupeptinas/farmacologia , Camundongos , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Complexo de Endopeptidases do Proteassoma/fisiologia , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/fisiologia , Células Tumorais Cultivadas
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