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1.
Clin Exp Immunol ; 217(1): 15-30, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38642912

RESUMO

B and T cells collaborate to drive autoimmune disease (AID). Historically, B- and T-cell (B-T cell) co-interaction was targeted through different pathways such as alemtuzumab, abatacept, and dapirolizumab with variable impact on B-cell depletion (BCD), whereas the majority of patients with AID including rheumatoid arthritis, systemic lupus erythematosus, multiple sclerosis, and organ transplantation benefit from targeted BCD with anti-CD20 monoclonal antibodies such as rituximab, ocrelizumab, or ofatumumab. Refractory AID is a significant problem for patients with incomplete BCD with a greater frequency of IgD-CD27+ switched memory B cells, CD19+CD20- B cells, and plasma cells that are not directly targeted by anti-CD20 antibodies, whereas most lymphoid tissue plasma cells express CD19. Furthermore, B-T-cell collaboration is predominant in lymphoid tissues and at sites of inflammation such as the joint and kidney, where BCD may be inefficient, due to limited access to key effector cells. In the treatment of cancer, chimeric antigen receptor (CAR) T-cell therapy and T-cell engagers (TCE) that recruit T cells to induce B-cell cytotoxicity have delivered promising results for anti-CD19 CAR T-cell therapies, the CD19 TCE blinatumomab and CD20 TCE such as mosunetuzumab, glofitamab, or epcoritamab. Limited evidence suggests that anti-CD19 CAR T-cell therapy may be effective in managing refractory AID whereas we await evaluation of TCE for use in non-oncological indications. Therefore, here, we discuss the potential mechanistic advantages of novel therapies that rely on T cells as effector cells to disrupt B-T-cell collaboration toward overcoming rituximab-resistant AID.


Assuntos
Doenças Autoimunes , Linfócitos B , Imunoterapia Adotiva , Linfócitos T , Humanos , Doenças Autoimunes/imunologia , Doenças Autoimunes/terapia , Linfócitos B/imunologia , Linfócitos T/imunologia , Imunoterapia Adotiva/métodos , Receptores de Antígenos Quiméricos/imunologia , Rituximab/uso terapêutico , Comunicação Celular/imunologia , Animais
2.
Eur Arch Otorhinolaryngol ; 281(6): 3017-3023, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38347197

RESUMO

PURPOSE: Nowadays, several efficacious biologic drugs are used for severe asthma with or without chronic rhinosinusitis with nasal polyps (CRSwNP). However, it has been observed that not all comorbid patients (asthma/CRSwNP) receiving biologic treatment for asthma experience satisfactory control of both conditions equally. METHODS: We selected 20 patients who had both severe asthma and comorbid CRSwNP under biological treatment with benralizumab, omalizumab or mepolizumab with adequate control of asthma but inadequate control of nasal symptoms. Patients were switched to dupilumab and outcomes were evaluated at baseline (T0), at 3 months (T1), at 6 months (T2), at 12 months (T3) and finally at 18 months (T4). Data were collected at each time point including blood tests measuring eosinophil levels and total IgE, SNOT22, ACT, NPS score, rhinomanometry, olfactory testing, and nasal cytology. RESULTS: The results showed an overall improvement in all the outcomes. Peripheral eosinophilia was observed consistently with existing literature. All patients registered an improvement in sinonasal outcomes, while only one patient had a worsening of asthma. Three patients interrupted the therapy due to various causes: poor asthma control, onset of psoriasis and thrombocytopenia. CONCLUSIONS: The response to a biologic treatment for CRSwNP control may be heterogenous and it seems that patients may benefit from switching improving control in equal measure in the upper and lower airway. Further studies to explore the endotype/phenotype which best fits with each biologic are mandatory to personalize the therapy.


Assuntos
Anticorpos Monoclonais Humanizados , Asma , Pólipos Nasais , Rinite , Sinusite , Humanos , Anticorpos Monoclonais Humanizados/uso terapêutico , Asma/tratamento farmacológico , Asma/complicações , Masculino , Feminino , Sinusite/tratamento farmacológico , Sinusite/complicações , Pólipos Nasais/tratamento farmacológico , Pólipos Nasais/complicações , Rinite/tratamento farmacológico , Rinite/complicações , Pessoa de Meia-Idade , Adulto , Doença Crônica , Antiasmáticos/uso terapêutico , Resultado do Tratamento , Substituição de Medicamentos , Índice de Gravidade de Doença
3.
Br J Clin Pharmacol ; 89(10): 2944-2949, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37480157

RESUMO

Health systems encourage switching from originators to biosimilars as biosimilars are more cost-effective. The speed and completeness of biosimilar adoption is a measure of efficiency. We describe the approach to biosimilar adoption at a single hospital Trust and compare its efficiency against the English average. We additionally follow up patients who reverted to a previously used biologic, having switched to a biosimilar, to establish whether they benefitted from re-establishing prior treatment. The approach we describe resulted in a faster and more complete switch to biosimilars, which saved an additional £380 000 on drug costs in 2021/2022. Of patients who reverted to their original biologic, 87% improved short-term, and a time on treatment analysis showed the benefit was retained long term. Our approach to biosimilar adoption outperformed the English average and permits patients to revert to their original biosimilar post-switch if appropriate.


Assuntos
Medicamentos Biossimilares , Humanos , Medicamentos Biossimilares/uso terapêutico , Seguimentos , Centros de Atenção Terciária , Reino Unido
4.
Rheumatology (Oxford) ; 61(2): 591-596, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33769451

RESUMO

OBJECTIVES: B cell depletion therapy based on rituximab in patients with RA was pioneered at University College London Hospitals/University College London in 1998. The objective of this study was to evaluate long-term persistence of rituximab and identify factors associated with discontinuation of treatment. METHODS: Retrospective review of medical records from all rituximab-treated RA patients followed up in a dedicated clinic (1998-2020). Data collected included gender, disease duration, previous DMARDs, autoantibody status, age and concomitant therapy at first cycle, length of follow-up, and number of cycles. Drug survival and factors associated with drug discontinuation were analysed using Kaplan-Meier survival curves, log-rank test and Cox regression analysis. RESULTS: A total of 404 patients were included. Median disease duration and age at time of first rituximab cycle were 10 and 57 years, respectively. Median total follow-up was 55 months and median number of cycles five. 93.1% of patients were seropositive. Overall, 31.2% of patients stopped rituximab, with the largest reason for discontinuing being primary inefficacy (42.1%). Comparison of Kaplan-Meier curves showed that rituximab drug survival was lower in seronegative patients and in patients who had previously failed at least one biologic DMARD (bDMARD). Cox regression analysis revealed that rituximab discontinuation was associated with a greater number of previous bDMARDs. CONCLUSION: Many patients with RA achieve good control of their disease with repeated cycles of rituximab treatment. The most common reasons for treatment discontinuation were either primary or secondary inefficacy. Patients who were seronegative and who had previously failed other bDMARDs were more at risk of drug discontinuation.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Rituximab/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antirreumáticos/uso terapêutico , Artrite Reumatoide/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
5.
Rheumatology (Oxford) ; 61(7): 2894-2904, 2022 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34788412

RESUMO

OBJECTIVES: To investigate key factors that may contribute to the variability of rituximab-mediated peripheral and renal B cell depletion (BCD) in SLE. METHODS: We analysed: (i) CD19+ B cell counts in patients with SLE before and 1, 2, 3 and 6 months after treatment with rituximab, comparing them with RA patients; (ii) the presence of B cells in renal biopsies after rituximab therapy; (iii) whether the duration of BCD correlated with patient demographics and B cell expression of CD20 and FcγRIIb; and (iv) the effect of B cell activation factor (BAFF) on the efficiency of rituximab and obinutuzumab at inducing BCD in whole blood assays, in vitro. RESULTS: In SLE (n = 71), the duration of BCD was shorter compared with RA (n = 27). B cells were detectable in renal biopsy samples (n = 6) after treatment with rituximab in all patients with poor response while peripheral blood B cells remained low or undetectable in the same patients. There were no significant relationships between peripheral BCD and patient age, disease duration, serum C3 levels or the level of expression of B cell surface proteins CD20 and FcγRIIb. Obinutuzumab was more efficient than rituximab at inducing BCD in whole blood assays, regardless of excess BAFF. CONCLUSIONS: BCD in SLE is less efficient than in RA. Renal B cell presence following rituximab treatment was associated with poor outcomes. No significant relationships between any measured B cell related, clinical or laboratory parameters and the efficiency of BCD by rituximab was found. Obinutuzumab was superior to rituximab at inducing BCD.


Assuntos
Lúpus Eritematoso Sistêmico , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Antígenos CD20 , Linfócitos B , Humanos , Rituximab/farmacologia , Rituximab/uso terapêutico
6.
Microb Pathog ; 173(Pt A): 105827, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36243385

RESUMO

Eugenol has already had its pharmacological properties elucidated in previous studies, including antibacterial and antifungal properties. Based on such information, this study aimed to evaluate the antibacterial and modulatory activity of coumarin compounds prepared from dihydroeugenol and to associate them with blue LED light for the same activity. For this study, five of the substances available: compound 1 (C1), 8-methoxy-2-oxo-6-propyl-2H-chromen-3-carboxylic acid, compound (C2), 3-(hydroxy(4-nitrophenyl)methyl)-8- methoxy-6-propyl-2H-chromen-2-one, compound 7 (C3), 8-hydroxy-3-(4-nitrobenzoyl)-6-propyl-2H-chromen-2-one, compound 8 (C4), 3-(4-aminobenzoyl)-8-methoxy-6-propyl-2H-chromen-2-one and Compound 9 (C5), 8-methoxy-3-(4-nitrobenzoyl)-6-propyl-2H-chromen-2-one 2-one. To determine the MIC, the broth microdilution technique was used. The products were evaluated for their potential to modulate the activity of antibiotics. Afterward, the plates were submitted to blue LED light for 20 min. When exposed to LED, C3 exhibited a decrease in MIC for SA ATCC and C5 for EC ATCC, with an average of 645.08 µg/mL for both cases. C2 and C4 exhibited synergism in a greater number of situations. However, C3 showed promising activity against S. aureus. C1 and C2 already acted better against E. coli, with the difference that C1 acted better against these bacteria when associated with LED. In general, the compounds studied here exhibited good antibacterial activity when associated with LED.


Assuntos
Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacologia , Bactérias , Luz , Testes de Sensibilidade Microbiana
7.
Lupus ; 30(3): 371-377, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33459161

RESUMO

It is now two decades since Rituximab was first used in the treatment of patients with systemic lupus erythematosus. There have been many challenges but in spite of failing to meet its primary endpoints in two clinical trials it is widely used for many aspects of lupus, its side-effects and the possibility that combining it with Benlysta may be of value. We also consider the proposal that it may provide a useful initial therapy. In this review, we consider the place of Rituximab in the treatment of lupus and anticipate how developments in fully-humanized anti-CD20 monoclonals may well extend the "therapeutic life" of B-cell depletion as a viable treatment option.


Assuntos
Fatores Imunológicos/administração & dosagem , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Rituximab/administração & dosagem , Anticorpos Monoclonais Humanizados/uso terapêutico , Linfócitos B/efeitos dos fármacos , Quimioterapia Combinada , Humanos , Fatores Imunológicos/efeitos adversos , Fatores Imunológicos/farmacologia , Imunossupressores/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Rituximab/efeitos adversos , Rituximab/farmacologia
8.
Biologicals ; 69: 1-14, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33288390

RESUMO

Systemic Lupus Erythematosus (SLE) is an autoimmune inflammatory condition with a wide spectrum of disease manifestations and severities, resulting in significant morbidity and mortality. The aetiopathogenesis of SLE is complex. Young women and certain ethnicities are commonly affected, suggesting a significant hormonal and genetic influence. Diverse immunological abnormalities have been described. A characteristic abnormality is the presence of autoantibodies, implicating a central role for B cells in disease pathogenesis and/or perpetuation. Whilst conventional therapies have improved outcomes, a great unmet need remains. Recently, biological therapies are being explored. B-cell depletion therapy with rituximab has been in use off-label for nearly two decades. Inconsistent results between uncontrolled and controlled studies have raised doubts about its efficacy. In this review, we will focus on B cell abnormalities and the rationale behind B-cell depletion therapy with anti-CD20 monoclonal antibody (mAb), rituximab, will be explored including an evaluation of clinical and trial experience. Finally, we will discuss the mechanistic basis for considering alternative anti-CD20 mAbs.


Assuntos
Anticorpos Monoclonais , Lúpus Eritematoso Sistêmico , Rituximab , Anticorpos Monoclonais/uso terapêutico , Antígenos CD20 , Linfócitos B , Humanos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Rituximab/uso terapêutico
9.
Int J Mol Sci ; 22(14)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34299237

RESUMO

Juvenile systemic lupus erythematosus (JSLE) is characterised by onset before 18 years of age and more severe disease phenotype, increased morbidity and mortality compared to adult-onset SLE. Management strategies in JSLE rely heavily on evidence derived from adult-onset SLE studies; therefore, identifying biomarkers associated with the disease pathogenesis and reflecting particularities of JSLE clinical phenotype holds promise for better patient management and improved outcomes. This narrative review summarises the evidence related to various traditional and novel biomarkers that have shown a promising role in identifying and predicting specific organ involvement in JSLE and appraises the evidence regarding their clinical utility, focusing in particular on renal biomarkers, while also emphasising the research into cardiovascular, haematological, neurological, skin and joint disease-related JSLE biomarkers, as well as genetic biomarkers with potential clinical applications.


Assuntos
Biomarcadores , Lúpus Eritematoso Sistêmico/patologia , Adolescente , Idade de Início , Autoanticorpos/imunologia , Biomarcadores/sangue , Biomarcadores/urina , Ceruloplasmina , Quimiocina CCL2 , Criança , Pré-Escolar , Feminino , Humanos , Oxirredutases Intramoleculares , Rim/patologia , Lipocalina-2 , Lipocalinas , Lúpus Eritematoso Sistêmico/metabolismo , Masculino , Orosomucoide , Fenótipo , Índice de Gravidade de Doença , Transferrina
10.
Br J Clin Pharmacol ; 86(1): 23-28, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31663154

RESUMO

Aims To assess the transfer of patients treated with originator biological therapies to biosimilar products in a large UK tertiary referral hospital reflecting practice within the National Health Service (NHS) using prospectively collected data by a hospital-based registry administered by the Biologics Steering Group (BSG). METHODS: We analysed data collected prospectively in a hospital-based registry in a large NHS tertiary referral hospital in the UK. The registry was administered by the hospital's BSG, which considered requests for patients to remain on or revert to originator products. The registry contained prospectively collected data on patients switching therapy from an originator to a biosimilar. The data included clinical circumstances or rationale for each request, whether it was granted, and the results of clinical reviews at 3-6 months. RESULTS: In a 12-month period, we identified 1299 patients who could switch to the respective biosimilar and, of these, 1196 (92%) did so. Of the 260 patients taking infliximab, 250 (96%) switched to infliximab biosimilar; of the 390 patients taking etanercept 50 mg, 298 (76%) switched to etanercept 50 mg biosimilar; and of the 649 patients taking rituximab, 648 (99%) switched to rituximab biosimilar. The BSG received 39 applications: 12 (out of 39) applications were to remain on the originator and 27 (out of 39) were to switch back to the originator. Of the applications to remain on the originator 10 (out of 12) were approved. At 3-6 month review, 2 of these approvals reported continued efficacy, 3 switched to the biosimilar, 3 switched to an alternative therapy and 2 stopped treatment. Two (out of 10) applications were not approved, both applicants reported efficacy with the biosimilar at follow up. Of the 27 applications to switch back to the originator, 16 (out of 27) applications were approved. At 3-6 months, 9 (out of 16) applicants reported regain of efficacy, 6 (out of 16) reported cessation of reported adverse effects and 1 (out of 16) switched to alternative therapy. Eight (out of 27) applications were not approved, and, at point of follow up, 50% reported efficacy with the biosimilar and 50% had switched to an alternative therapy. Three (out of 27) applications were withdrawn by the clinical team as efficacy was achieved with the biosimilar. CONCLUSION: We have set up a system within a busy NHS clinical practice to successfully switch patients to biosimilars, and established a mechanism to guide decisions on continuing with or reverting back to the originator. Such a system could be of use more broadly within the NHS and other health care systems.


Assuntos
Medicamentos Biossimilares , Humanos , Infliximab/uso terapêutico , Medicina Estatal , Centros de Atenção Terciária , Reino Unido
11.
J Immunol ; 200(5): 1937-1950, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29351998

RESUMO

Fc γ receptors (FcγR) are involved in multiple aspects of immune cell regulation, are central to the success of mAb therapeutics, and underpin the pathology of several autoimmune diseases. However, reliable assays capable of accurately measuring FcγR interactions with their physiological ligands, IgG immune complexes (IC), are limited. A method to study and detect IC interactions with FcγRs was therefore developed. This method, designed to model the signaling pathway of the inhibitory FcγRIIB (CD32B), used NanoLuc Binary Interaction Technology to measure recruitment of the Src homology 2 domain-containing inositol phosphatase 1 to the ITIM of this receptor. Such recruitment required prior cross-linking of an ITAM-containing activatory receptor, and evoked luciferase activity in discrete clusters at the cell surface, recapitulating the known biology of CD32B signaling. The assay detected varying forms of experimental IC, including heat-aggregated IgG, rituximab-anti-idiotype complexes, and anti-trinitrophenol-trinitrophenol complexes in a sensitive manner (≤1 µg/ml), and discriminated between complexes of varying size and isotype. Proof-of-concept for the detection of circulating ICs in autoimmune disease was provided, as responses to sera from patients with systemic lupus erythematosus and rheumatoid arthritis were detected in small pilot studies. Finally, the method was translated to a stable cell line system. In conclusion, a rapid and robust method for the detection of IC was developed, which has numerous potential applications including the monitoring of IC in autoimmune diseases and the study of underlying FcγR biology.


Assuntos
Complexo Antígeno-Anticorpo/imunologia , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/imunologia , Receptores de IgG/imunologia , Artrite Reumatoide/imunologia , Doenças Autoimunes/imunologia , Linhagem Celular , Células HEK293 , Humanos , Imunoglobulina G/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Fosfoproteínas/imunologia , Rituximab/imunologia , Transdução de Sinais/imunologia , Domínios de Homologia de src/imunologia
12.
Rheumatology (Oxford) ; 58(11): 2031-2038, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31089697

RESUMO

OBJECTIVES: Lung involvement in RA has several manifestations and is a major cause of morbidity and mortality. The aim of this study was to characterize the different types of lung disease and response to treatment in a UK cohort of RA patients. METHODS: RA patients who had undergone high resolution CT scans of the lung were identified and scans reviewed. Demographic data, RA features, complementary exams and treatments were recorded for those with radiological evidence of lung involvement. Descriptive analysis was performed, and Mann-Whitney U and χ2 tests were used for comparison between different radiological subtypes. RESULTS: Lung disease was reported in 87 (7.7%) of 1129 RA patients, usually (97.7%) post-dating articular symptoms. Most patients had positive RF (74/84; 88.1%) and ACPA (72/82; 87.7%). Interstitial lung disease (ILD) was the most common pattern, reported in 45 (51.7%) patients. Drug-induced lung disease was reported in 2 of 64 (3.1%) patients treated with MTX. Rituximab was used in 26 (57.8%) patients with ILD, with evidence of disease improvement or stabilization in patients with non-specific interstitial pneumonia and organizing pneumonia. During lung disease follow-up (6.7 ± 4.1 years), 22 (25.3%) patients were admitted to hospital with respiratory infections, with 14 (63.6%) of them having underlying bronchiectasis. Lung disease-related mortality was estimated at 8%. CONCLUSION: ILD was the most prevalent manifestation of lung involvement in RA and was associated with higher mortality. Immunosuppressive drugs used in RA were rarely associated with lung toxicity, and rituximab demonstrated promising results for the treatment of RA-ILD.


Assuntos
Artrite Reumatoide/complicações , Doenças Pulmonares Intersticiais/etiologia , Pneumopatias/etiologia , Tomografia Computadorizada por Raios X , Idoso , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/mortalidade , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pneumopatias/diagnóstico por imagem , Pneumopatias/mortalidade , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Rituximab/uso terapêutico , Reino Unido
13.
Rheumatology (Oxford) ; 58(10): 1831-1838, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31046100

RESUMO

OBJECTIVES: To develop evidence-based recommendations on the use of MRI in the diagnosis of axial SpA (axSpA). METHODS: A working group comprising nine rheumatologists and nine musculoskeletal radiologists with an interest in axSpA was established, with support from the British Society of Spondyloarthritis (BRITSpA). Two meetings were held. In the first meeting, research questions were formulated. In the second meeting, the results of a systematic literature review designed to inform the recommendations were reviewed. An anonymized Delphi process was used to formulate the final set of recommendations. For each recommendation, the level of evidence and strength of recommendation was determined. The level of agreement was assessed using a 0-10 numerical rating scale. RESULTS: Two overarching principles were formulated, as follows: The diagnosis of axSpA is based on clinical, laboratory and imaging features (overarching principle 1), and patients with axSpA can have isolated inflammation of either the sacroiliac joints or the spine (overarching principle 2). Seven recommendations addressing the use of MRI in the assessment of patients with suspected axSpA were formulated, covering topics including recommended sequences, anatomical coverage, acquisition parameters and interpretation of active and structural MRI lesions. The level of agreement for each recommendation was very high (range 8.8-9.8). CONCLUSION: A joint rheumatology and radiology consensus on the acquisition and interpretation of MRI in axSpA diagnosis was achieved, and a research agenda formulated. This consensus should help standardize practice around MRI and ensure a more informed, consistent approach to the diagnosis of axSpA.


Assuntos
Imageamento por Ressonância Magnética/normas , Radiologia/normas , Reumatologia/normas , Articulação Sacroilíaca/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Espondilartrite/diagnóstico , Técnica Delphi , Humanos , Guias de Prática Clínica como Assunto , Reino Unido
14.
Rheumatology (Oxford) ; 56(7): 1227-1237, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28407142

RESUMO

Objective: A proportion of RA and SLE patients treated with standard doses of rituximab (RTX) display inefficient B cell deletion and poor clinical responses that can be augmented by delivering higher doses, indicating that standard-dose RTX is a sub-optimal therapy in these patients. This study aimed to investigate whether better responses could be achieved with mechanistically different anti-CD20 mAbs. Methods: We compared RTX with obinutuzumab (OBZ), a new-generation, glycoengineered type II anti-CD20 mAb, in a series of in vitro assays measuring B cell cytotoxicity in RA and SLE patient samples. Results: We found that OBZ was at least 2-fold more efficient than RTX at inducing B-cell cytotoxicity in in vitro whole blood assays. Dissecting this difference, we found that RTX elicited more potent complement-dependent cellular cytotoxicity than OBZ. In contrast, OBZ was more effective at evoking Fc gamma receptor-mediated effector mechanisms, including activation of NK cells and neutrophils, probably due to stronger interaction with Fc gamma receptors and the ability of OBZ to remain at the cell surface following CD20 engagement, whereas RTX became internalized. OBZ was also more efficient at inducing direct cell death. This was true for all CD19 + B cells as a whole and in naïve (IgD + CD27 - ) and switched (IgD - CD27 + ) memory B cells specifically, a higher frequency of which is associated with poor clinical response after RTX. Conclusion: Taken together, these data provide a mechanistic basis for resistance to rituximab-induced B-cell depletion, and for considering obinutuzumab as an alternative B-cell depleting agent in RA and SLE.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Apoptose/efeitos dos fármacos , Artrite Reumatoide/tratamento farmacológico , Linfócitos B/efeitos dos fármacos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Rituximab/farmacologia , Adulto , Antirreumáticos/farmacologia , Artrite Reumatoide/sangue , Células Cultivadas , Feminino , Humanos , Técnicas In Vitro , Lúpus Eritematoso Sistêmico/sangue , Masculino , Pessoa de Meia-Idade , Receptores de IgG/efeitos dos fármacos , Receptores de IgG/metabolismo , Estudos de Amostragem , Estatísticas não Paramétricas , Adulto Jovem
15.
J Autoimmun ; 70: 22-30, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27055777

RESUMO

The serology of patients with Rheumatoid arthritis (RA) is characterized by persistently raised levels of autoantibodies: Rheumatoid Factors (RhF) against Fc of IgG, and to citrullinated (Cit) protein/peptide sequences: ACPA, recognizing multiple Cit-sequences. B cell depletion therapy based on rituximab delivers good clinical responses in RA patients, particularly in the seropositive group, with responses sometimes lasting beyond the phase of B cell reconstitution. In general, ACPA levels fall following rituximab, but fluctuations with respect to predicting relapse have proved disappointing. In order to identify possible immunodominant specificities within either IgG- or IgA-ACPA we used a Multiplex bead-based array consisting of 30 Cit-peptides/proteins and 22 corresponding native sequences. The kinetics of the serum ACPA response to individual specificities was measured at key points (Baseline, B cell depletion phase, Relapse) within an initial cycle of rituximab therapy in 16 consecutive patients with severe, active RA. All had achieved significant decreases in Disease Activity Scores-28 and maintained B cell depletion in the peripheral blood (<5 CD19+cells/µl) for at least 3 months. At Baseline, mean fluorescence intensity shown by individual IgG- and IgA-ACPA were strongly correlated (R(2) = 0.75; p < 0.0001) but IgA-ACPA were approximately 10-fold lower. Data were Z-normalised in order to compare serial results and antibody classes. At Baseline, a total of 68 IgG- and 51 IgA-ACPA had Z-scores ≥ 1 (above population mean) were identified, with at least one Cit-antigen identified in each serum. ACPA to individual specificities subsequently fluctuated with 3 different patterns. Most 51/68 (75%) IgG- and 48/51 IgA-ACPA (94%) fell between Baseline and Depletion, of which 57% IgG- and 65% IgA-ACPA rebounded pre-Relapse. Interestingly, 17/68 IgG-ACPA (25%) and some IgA-ACPA (3/51; 6%) transiently increased from Baseline, subsequently falling pre-Relapse. Individual responses to particular Cit-epitopes were not linked to particular patterns of fluctuation, but IgG- and IgA-ACPA to individual Cit-antigens often followed similar courses. Some new IgG- and IgA-ACPA, generally to different Cit-antigens however, arose at Relapse in 4 patients. The complexities of the ACPA response after rituximab may therefore reflect its ability to deplete or modify the function of parent B cell clones, which varies between patients. Although relapse following rituximab invariably follows naïve B cell exit from the bone marrow, these studies show that interactions between both 'new' and residual autoreactive memory B cells may be key to resumption of symptoms. The lack of identification of any immunodominant specificity suggests that the process of citrullination, rather than any particular Cit-antigen drives the autoimmune response in RA patients.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/imunologia , Linfócitos B/imunologia , Depleção Linfocítica , Rituximab/uso terapêutico , Adulto , Idoso , Antirreumáticos/farmacologia , Autoanticorpos/sangue , Autoanticorpos/imunologia , Autoantígenos/imunologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Análise por Conglomerados , Quimioterapia Combinada , Mapeamento de Epitopos , Epitopos/imunologia , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Depleção Linfocítica/métodos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/imunologia , Fator Reumatoide , Rituximab/farmacologia , Resultado do Tratamento
16.
BMC Pregnancy Childbirth ; 16(1): 139, 2016 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-27267973

RESUMO

BACKGROUND: B cells play a role in pregnancy due to their humoral and regulatory activities. To our knowledge, different maturational stages (from transitional to memory) of circulating B cell subsets have not yet been characterized (cell quantification and phenotype identification) in healthy pregnant women. Thus, the objective of our study was to characterize these subsets (as well as regulatory B cells) from late pregnancy to post-partum and to compare them with the circulating B cells of non-pregnant women. METHODS: In all of the enrolled women, flow cytometry was used to characterize the circulating B cell subsets according to the expression of IgD and CD38 (Bm1-Bm5 classification system). Regulatory B cells were characterized based on the expression of surface antigens (CD24, CD27, and CD38) and the production of IL-10 after lipopolysaccharide stimulation. RESULTS: Compared to the absolute counts of B cells in the non-pregnant women (n = 35), those in the pregnant women (n = 43) were significantly lower (p < 0.05) during the 3rd trimester of pregnancy and on delivery day (immediately after delivery). The percentages of these cells on delivery day and at post-partum were significantly lower than those in the non-pregnant women. In general, the absolute counts and percentages of the majority of the B cell subsets were significantly lower in the 3rd trimester of pregnancy and on delivery day than in the non-pregnant women. However, these counts and percentages did not differ significantly between the post-partum and the non-pregnant women. The most notable exceptions to the above were the percentages of naïve B cells (which were significantly higher in the 3rd trimester and on delivery day than in the non-pregnant women) and of CD24(hi)CD38(hi) regulatory B cells (which were significantly higher in the post-partum than in the non-pregnant women). CONCLUSION: According to our study, the peripheral B cell compartment undergoes quantitative changes during normal late pregnancy and post-partum. Such findings may allow us to better understand immunomodulation during human pregnancy and provide evidence that could aid in the development of new strategies to diagnose and treat pregnancy-associated disturbances. Our findings could also be useful for studies of the mechanisms of maternal responses to vaccination and infection.


Assuntos
Linfócitos B Reguladores/metabolismo , Parto/sangue , Período Pós-Parto/sangue , Terceiro Trimestre da Gravidez/sangue , ADP-Ribosil Ciclase 1/sangue , Adulto , Antígeno CD24/sangue , Feminino , Citometria de Fluxo , Voluntários Saudáveis , Humanos , Interleucina-10/sangue , Glicoproteínas de Membrana/sangue , Gravidez , Estudos Prospectivos , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/sangue
17.
Microbiology (Reading) ; 161(10): 2008-2018, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26253443

RESUMO

Fructophily has been described in yeasts as the ability to utilize fructose preferentially when fructose and glucose are available in the environment. In Zygosaccharomyces bailii and Zygosaccharomyces rouxii, fructophilic behaviour has been associated with the presence of a particular type of high-capacity and low-affinity fructose transporters designated Ffz. In this study, a PCR screening was performed in several yeasts using degenerate primers suitable to detect FFZ-like genes. In parallel, fructophilic character was evaluated in the same strains by comparing the relative consumption rate of fructose and glucose. For all the strains in which FFZ-like genes were detected, fructophilic behaviour was observed (25 strains). Results show that FFZ genes are ubiquitous in the Zygosaccharomyces and Starmerella clades. Strains of Lachancea fermentati, Torulaspora microellipsoides and Zygotorulaspora florentina were not fructophilic and did not harbour FFZ genes. It is of note that these new species were recently removed by taxonomists from the Zygosaccharomyces clade, supporting the view that the presence of FFZ-like genes is a main characteristic of Zygosaccharomyces. Among the strains tested, only Hanseniaspora guilliermondii NCYC2380 was an exception, having a preference for fructose in medium with high sugar concentrations, despite no FFZ-like genes being detected in the screening. Furthermore, this study supports the previous idea of the emergence of a new family of hexose transporters (Ffz facilitators) distinct from the Sugar Porter family.


Assuntos
Frutose/metabolismo , Proteínas de Transporte de Monossacarídeos/genética , Proteínas de Transporte de Monossacarídeos/metabolismo , Saccharomycetales/genética , Saccharomycetales/metabolismo , DNA Fúngico/química , DNA Fúngico/genética , Testes Genéticos , Glucose/metabolismo , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
18.
Eukaryot Cell ; 13(11): 1371-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25172765

RESUMO

Zygosaccharomyces rouxii is a fructophilic yeast that consumes fructose preferably to glucose. This behavior seems to be related to sugar uptake. In this study, we constructed Z. rouxii single-, double-, and triple-deletion mutants in the UL4 strain background (a ura3 strain derived from CBS 732(T)) by deleting the genes encoding the specific fructose facilitator Z. rouxii Ffz1 (ZrFfz1), the fructose/glucose facilitator ZrFfz2, and/or the fructose symporter ZrFsy1. We analyzed the effects on the growth phenotype, on kinetic parameters of fructose and glucose uptake, and on sugar consumption profiles. No growth phenotype was observed on fructose or glucose upon deletion of FFZ genes. Deletion of ZrFFZ1 drastically reduced fructose transport capacity, increased glucose transport capacity, and eliminated the fructophilic character, while deletion of ZrFFZ2 had almost no effect. The strain in which both FFZ genes were deleted presented even higher consumption of glucose than strain Zrffz1Δ, probably due to a reduced repressing effect of fructose. This study confirms the molecular basis of the Z. rouxii fructophilic character, demonstrating that ZrFfz1 is essential for Z. rouxii fructophilic behavior. The gene is a good candidate to improve the fructose fermentation performance of industrial Saccharomyces cerevisiae strains.


Assuntos
Transporte Biológico/genética , Frutose/metabolismo , Zygosaccharomyces/genética , Zygosaccharomyces/metabolismo , Proliferação de Células/genética , Fermentação/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Técnicas de Silenciamento de Genes , Glucose/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
19.
Artigo em Inglês | MEDLINE | ID: mdl-38266634

RESUMO

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) may have a heterogeneous response to medical/surgical treatments based on endotypes. Data correlating biomarkers and severity of the disease are lacking. We aimed to determine if IL-5 and calprotectin may be useful in defining severity of disease and identifying uncontrolled patients. METHODS: This was a case-control study including 81 patients with diffuse CRSwNP who underwent at least one previous surgery and treated with intranasal steroids. We enrolled 39 uncontrolled patients (SNOT-22 ≥ 40 and two or more cycles of systemic corticosteroids in last year) (Group A) and 42 controlled one (SNOT-22 < 40 and less than two cycles of systemic corticosteroids in last year) (Group B). We analyzed IL-5 and calprotectin in both nasal secretions and nasal polyp tissue. RESULTS: Calprotectin and IL-5 were significantly higher in Group A in both secretions and tissue, and the higher the number of previous surgeries, the higher the levels detected in nasal secretions. At univariate analyses, smoking, asthma, non-steroidal anti-inflammatory drugs-exacerbated respiratory disease (NSAID-ERD), blood eosinophilia, neutrophils, and eosinophils at nasal cytology were significantly associated with uncontrolled disease. Multivariate analyses showed that asthma, NSAID-ERD, and IL-5 in nasal secretion/polyp tissue were significantly related to the risk of uncontrolled disease. CONCLUSIONS: Our data suggest that asthma, NSAID-ERD, and IL-5 in nasal secretions/tissue may be helpful to identify more severe patients, as they are related to the risk of uncontrolled disease. Nonetheless, high levels of calprotectin and neutrophilia were also observed in uncontrolled patients, especially after multiple surgeries.

20.
Dermatol Ther ; 26(4): 370-2, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23914896

RESUMO

Two patients with a long-standing history of recalcitrant ankylosing spondylitis were commenced on adalimumab as monotherapy. Case 1 developed marked rapid deterioration in his previously stable vitiligo within 3 months of commencing treatment. This was attributed to anti-tumor necrosis factor (TNF) therapy, and a marked improvement was noted following withdrawal of adalimumab. Case 2 developed multiple new halo naevi over the trunk and limbs. They did not show dysplastic features and have remained unchanged despite continuation of treatment. Possible mechanisms and implications of the paradoxical occurrence of immune-mediated skin lesions seen in patients receiving anti-TNF therapies are discussed.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Nevo com Halo/induzido quimicamente , Fator de Necrose Tumoral alfa/imunologia , Vitiligo/induzido quimicamente , Adalimumab , Adulto , Humanos , Masculino , Pessoa de Meia-Idade
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