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1.
Commun Biol ; 4(1): 1186, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34650224

RESUMO

The adoptive transfer of regulatory T-cells (Tregs) is a promising therapeutic approach in transplantation and autoimmunity. However, because large cell numbers are needed to achieve a therapeutic effect, in vitro expansion is required. By comparing their function, phenotype and transcriptomic profile against ex vivo Tregs, we demonstrate that expanded human Tregs switch their metabolism to aerobic glycolysis and show enhanced suppressive function through hypoxia-inducible factor 1-alpha (HIF1A) driven acquisition of CD73 expression. In conjunction with CD39, CD73 expression enables expanded Tregs to convert ATP to immunosuppressive adenosine. We conclude that for maximum therapeutic benefit, Treg expansion protocols should be optimised for CD39/CD73 co-expression.


Assuntos
5'-Nucleotidase/genética , Regulação da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Linfócitos T Reguladores/metabolismo , 5'-Nucleotidase/metabolismo , Feminino , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino
2.
Commun Biol ; 4(1): 798, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-34172826

RESUMO

The central goal of regenerative medicine is to replace damaged or diseased tissue with cells that integrate and function optimally. The capacity of pluripotent stem cells to produce unlimited numbers of differentiated cells is of considerable therapeutic interest, with several clinical trials underway. However, the host immune response represents an important barrier to clinical translation. Here we describe the role of the host innate and adaptive immune responses as triggers of allogeneic graft rejection. We discuss how the immune response is determined by the cellular therapy. Additionally, we describe the range of available in vitro and in vivo experimental approaches to examine the immunogenicity of cellular therapies, and finally we review potential strategies to ameliorate immune rejection. In conclusion, we advocate establishment of platforms that bring together the multidisciplinary expertise and infrastructure necessary to comprehensively investigate the immunogenicity of cellular therapies to ensure their clinical safety and efficacy.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Medicina Regenerativa , Engenharia Genética , Rejeição de Enxerto/imunologia , Teste de Histocompatibilidade , Humanos , Tolerância Imunológica , Imunidade Inata , Ativação Linfocitária , Transplante de Células-Tronco , Linfócitos T/imunologia
3.
Oncol Rep ; 44(4): 1717-1726, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32945506

RESUMO

Human papillomavirus­positive (HPV+) oropharyngeal squamous cell carcinoma (OPSCC) has increased in incidence and has a much better prognosis than HPV­negative (HPV­) OPSCC with radiotherapy alone, but exactly why is unknown. The present study therefore aimed to further examine the sensitivity and possible changes in gene expression of several HPV+ and HPV­ OPSCC, including various novel cell lines, upon ionizing irradiation (IR). Previously established HPV+ UM­SCC­47, UPCI­SCC­90, CU­OP­2, CU­OP­3 and HPV­ UM­SCC­4, UM­SCC­6, UM­SCC­74a, UM­SCC­19 and newly established CU­OP­17 and CU­OP­20, characterised here, were subjected to 0­6 Gy. Surviving fractions of each cell line were tested by clonogenic assays, and irregularities in cell cycle responses were examined by flow cytometry, while changes in gene expression were followed by mRNA sequencing. HPV+ OPSCC cell lines showed greater variation in sensitivity to ionizing irradiation (IR) and tended to be more sensitive than HPV­ OPSCC cell lines. However, their IR sensitivity was not correlated to the proportion of cells in G2 arrest, and HPV­ cell lines generally showed lower increases in G2 after IR. Upon IR with 2 Gy, mRNA sequencing revealed an increase in minor HPV integration sites in HPV+ cell lines, and some changes in gene expression in OPSCC cell lines, but not primarily those associated with DNA repair. To conclude, HPV+ OPSCC cell lines showed greater variation in their sensitivity to IR, with some that were radioresistant, but overall the HPV+ OPSCC group still tended to be more sensitive to IR than the HPV­ OPSCC group. In addition, HPV+ OPSCC lines were more frequently in G2 as compared to HPV­ cell lines, but the increase in G2 arrest upon IR in HPV+ OPSCC was not correlated to sensitivity to IR. Increases in minor HPV integration sites and changes in gene expression were also demonstrated after irradiation with 2 Gy.


Assuntos
Infecções por Papillomavirus/radioterapia , Tolerância a Radiação/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Alphapapillomavirus/isolamento & purificação , Alphapapillomavirus/patogenicidade , Linhagem Celular Tumoral , Reparo do DNA/efeitos da radiação , Humanos , Infecções por Papillomavirus/virologia , RNA Mensageiro/genética , Radiação Ionizante , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia
4.
Eur Thyroid J ; 8(4): 173-185, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31602359

RESUMO

Thyroid dysfunction (TD) frequently occurs as an autoimmune complication of immune reconstitution therapy (IRT), especially in individuals with multiple sclerosis treated with alemtuzumab, a pan-lymphocyte depleting drug with subsequent recovery of immune cell numbers. Less frequently, TD is triggered by highly active antiretroviral therapy (HAART) in patients infected with human immunodeficiency virus (HIV), or patients undergoing bone-marrow/hematopoietic-stem-cell transplantation (BMT/HSCT). In both alemtuzumab-induced TD and HIV/HAART patients, the commonest disorder is Graves' disease (GD), followed by hypothyroidism and thyroiditis; Graves' orbitopathy is observed in some GD patients. On the contrary, GD is rare post-BMT/HSCT, where hypothyroidism predominates probably as a consequence of the associated radiation damage. In alemtuzumab-induced TD, the autoantibodies against the thyrotropin receptor (TRAb) play a major role, and 2 main aspects distinguish this condition from the spontaneous form: (1) up to 20% of GD cases exhibit a fluctuating course, with alternating phases of hyper- and hypothyroidism, due to the coexistence of TRAb with stimulating and blocking function; (2) TRAb are also positive in about 70% of hypothyroid patients, with blocking TRAb responsible for nearly half of the cases. The present guidelines will provide up-to-date recommendations and suggestions dedicated to all phases of IRT-induced TD: (1) screening before IRT (recommendations 1-3); (2) monitoring during/after IRT (recommendations 4-7); (3) management of TD post-IRT (recommendations 8-17). The clinical management of IRT-induced TD, and in particular GD, can be challenging. In these guidelines, we propose a summary algorithm which has particular utility for nonspecialist physicians and which is tailored toward management of alemtuzumab-induced TD. However, we recommend prompt referral to specialist endocrinology services following diagnosis of any IRT-induced TD diagnosis, and in particular for pregnant women and those considering pregnancy.

5.
JCI Insight ; 52019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-31063156

RESUMO

BACKGROUND: The lymphocyte-depleting antibody alemtuzumab is a highly effective treatment of relapsing-remitting multiple sclerosis (RRMS); however 50% of patients develop novel autoimmunity post-treatment. Most at risk are individuals who reconstitute their T-cell pool by proliferating residual cells, rather than producing new T-cells in the thymus; raising the possibility that autoimmunity might be prevented by increasing thymopoiesis. Keratinocyte growth factor (palifermin) promotes thymopoiesis in non-human primates. METHODS: Following a dose-tolerability sub-study, individuals with RRMS (duration ≤10 years; expanded disability status scale ≤5·0; with ≥2 relapses in the previous 2 years) were randomised to placebo or 180mcg/kg/day palifermin, given for 3 days immediately prior to and after each cycle of alemtuzumab, with repeat doses at M1 and M3. The interim primary endpoint was naïve CD4+ T-cell count at M6. Exploratory endpoints included: number of recent thymic-emigrants (RTEs) and signal-joint T-cell receptor excision circles (sjTRECs)/mL of blood. The trial primary endpoint was incidence of autoimmunity at M30. FINDINGS: At M6, individuals receiving palifermin had fewer naïve CD4+T-cells (2.229x107/L vs. 7.733x107/L; p=0.007), RTEs (16% vs. 34%) and sjTRECs/mL (1100 vs. 3396), leading to protocol-defined termination of recruitment. No difference was observed in the rate of autoimmunity between the two groupsConclusion: In contrast to animal studies, palifermin reduced thymopoiesis in our patients. These results offer a note of caution to those using palifermin to promote thymopoiesis in other settings, particularly in the oncology/haematology setting where alemtuzumab is often used as part of the conditioning regime. TRIAL REGISTRATION: ClinicalTrials.gov NCT01712945Funding: MRC and Moulton Charitable Foundation.


Assuntos
Fator 7 de Crescimento de Fibroblastos/farmacologia , Linfopenia/tratamento farmacológico , Adolescente , Adulto , Animais , Linfócitos T CD4-Positivos/imunologia , Antígeno CD52/metabolismo , Modelos Animais de Doenças , Feminino , Fator 7 de Crescimento de Fibroblastos/uso terapêutico , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/imunologia , Adulto Jovem
7.
Eye (Lond) ; 33(2): 223-229, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30498266

RESUMO

Alemtuzumab-a monoclonal antibody targeting the CD52 glycoprotein expressed by most mature leucocytes-effectively decreases relapse rate and disability progression in early, relapsing-remitting multiple sclerosis (MS). However, secondary autoimmune disorders complicate therapy in nearly 50% of treated patients, with Graves' disease being the most common. Rarely, thyroid eye disease (TED) ensues; only seven such cases have been reported. Our aim was to analyse the largest series of MS patients developing thyroid eye disease after alemtuzumab treatment. We performed a retrospective chart review of MS patients treated with alemtuzumab (1995-2018) and subsequently identified by their treating physicians as having developed TED and referred to our ophthalmology service. As an original trial centre for alemtuzumab, our hospital has treated approximately 162 MS patients with this novel therapy. In total, 71 (44%) developed thyroid dysfunction, most of whom (87%) developed Graves' disease, with ten (16%) referred for ophthalmological evaluation. Two developed active orbitopathy following radioiodine treatment; one occurred after cessation of anti-thyroid drug treatment. Three developed sight-threatening disease requiring systemic immunosuppression, with one refractory to multiple immunosuppressants. The remaining patients were treated conservatively. TSH-receptor antibody (TRAb) levels were significantly raised in all cases, when ascertained. We report sight-threatening as well as mild TED in MS patients after treatment with alemtuzumab. Endocrine instability, radioiodine treatment and positive TRAb are all likely risk factors. The data support at least 6-monthly biochemical and clinical assessment with a low threshold for referral to an ophthalmologist, particularly for those with higher TRAb levels who may be at greater risk of orbitopathy.


Assuntos
Alemtuzumab/efeitos adversos , Antineoplásicos Imunológicos/efeitos adversos , Oftalmopatia de Graves/induzido quimicamente , Reconstituição Imune , Esclerose Múltipla/tratamento farmacológico , Adolescente , Adulto , Autoanticorpos/sangue , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Oftalmopatia de Graves/diagnóstico por imagem , Oftalmopatia de Graves/imunologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/imunologia , Receptores da Tireotropina/imunologia , Recidiva , Estudos Retrospectivos , Fatores de Risco
9.
Brain ; 141(3): 786-796, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29361022

RESUMO

The increasing evidence supporting a role for B cells in the pathogenesis of multiple sclerosis prompted us to investigate the influence of known susceptibility variants on the surface expression of co-stimulatory molecules in these cells. Using flow cytometry we measured surface expression of CD40 and CD86 in B cells from 68 patients and 162 healthy controls that were genotyped for the multiple sclerosis associated single nucleotide polymorphisms (SNPs) rs4810485, which maps within the CD40 gene, and rs9282641, which maps within the CD86 gene. We found that carrying the risk allele rs4810485*T lowered the cell-surface expression of CD40 in all tested B cell subtypes (in total B cells P ≤ 5.10 × 10-5 in patients and ≤4.09 × 10-6 in controls), while carrying the risk allele rs9282641*G increased the expression of CD86, with this effect primarily seen in the naïve B cell subset (P = 0.048 in patients and 5.38 × 10-5 in controls). In concordance with these results, analysis of RNA expression demonstrated that the risk allele rs4810485*T resulted in lower total CD40 expression (P = 0.057) but with an increased proportion of alternative splice-forms leading to decoy receptors (P = 4.00 × 10-7). Finally, we also observed that the risk allele rs4810485*T was associated with decreased levels of interleukin-10 (P = 0.020), which is considered to have an immunoregulatory function downstream of CD40. Given the importance of these co-stimulatory molecules in determining the immune reaction that appears in response to antigen our data suggest that B cells might have an important antigen presentation and immunoregulatory role in the pathogenesis of multiple sclerosis.


Assuntos
Linfócitos B/metabolismo , Antígeno B7-2/genética , Antígenos CD40/genética , Predisposição Genética para Doença/genética , Esclerose Múltipla/genética , Polimorfismo de Nucleotídeo Único/genética , Linfócitos B/patologia , Correlação de Dados , Citocinas/sangue , Feminino , Regulação da Expressão Gênica/genética , Genótipo , Humanos , Interleucina-10/metabolismo , Masculino , Esclerose Múltipla/sangue , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia
10.
JCI Insight ; 2(16)2017 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28814669

RESUMO

The maintenance of peripheral naive T lymphocytes in humans is dependent on their homeostatic division, not continuing emigration from the thymus, which undergoes involution with age. However, postthymic maintenance of naive T cells is still poorly understood. Previously we reported that recent thymic emigrants (RTEs) are contained in CD31+CD25- naive T cells as defined by their levels of signal joint T cell receptor rearrangement excision circles (sjTRECs). Here, by differential gene expression analysis followed by protein expression and functional studies, we define that the naive T cells having divided the least since thymic emigration express complement receptors (CR1 and CR2) known to bind complement C3b- and C3d-decorated microbial products and, following activation, produce IL-8 (CXCL8), a major chemoattractant for neutrophils in bacterial defense. We also observed an IL-8-producing memory T cell subpopulation coexpressing CR1 and CR2 and with a gene expression signature resembling that of RTEs. The functions of CR1 and CR2 on T cells remain to be determined, but we note that CR2 is the receptor for Epstein-Barr virus, which is a cause of T cell lymphomas and a candidate environmental factor in autoimmune disease.

12.
Int J Radiat Oncol Biol Phys ; 95(5): 1513-1519, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27262359

RESUMO

PURPOSE: To prospectively evaluate a protocol for transit dosimetry on a patient population undergoing intensity modulated radiation therapy (IMRT) and to assess the issues in clinical implementation of electronic portal imaging devices (EPIDs) for treatment verification. METHODS AND MATERIALS: Fifty-eight patients were enrolled in the study. Amorphous silicon EPIDs were calibrated for dose and used to acquire images of delivered fields. Measured EPID dose maps were back-projected using the planning computed tomographic (CT) images to calculate dose at prespecified points within the patient and compared with treatment planning system dose offline using point dose difference and point γ analysis. The deviation of the results was used to inform future action levels. RESULTS: Two hundred twenty-five transit images were analyzed, composed of breast, prostate, and head and neck IMRT fields. Patient measurements demonstrated the potential of the dose verification protocol to model dose well under complex conditions: 83.8% of all delivered beams achieved the initial set tolerance level of ΔD of 0 ± 5 cGy or %ΔD of 0% ± 5%. Importantly, the protocol was also sensitive to anatomic changes and spotted that 3 patients from 20 measured prostate patients had undergone anatomic change in comparison with the planning CT. Patient data suggested an EPID-reconstructed versus treatment planning system dose difference action level of 0% ± 7% for breast fields. Asymmetric action levels were more appropriate for inversed IMRT fields, using absolute dose difference (-2 ± 5 cGy) or summed field percentage dose difference (-6% ± 7%). CONCLUSIONS: The in vivo dose verification method was easy to use and simple to implement, and it could detect patient anatomic changes that impacted dose delivery. The system required no extra dose to the patient or treatment time delay and so could be used throughout the course of treatment to identify and limit systematic and random errors in dose delivery for patient groups.


Assuntos
Neoplasias/diagnóstico , Neoplasias/radioterapia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/instrumentação , Ecrans Intensificadores para Raios X , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
13.
Surgery ; 157(3): 432-43, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25633735

RESUMO

BACKGROUND: The transition from student to intern can be challenging. The "August" or "July effect" describes increased errors and reduced patient safety during this transition. The study objectives were to develop, pilot, and evaluate clinical performance after an immersive simulation course for incoming interns. METHODS: Graduating students were recruited for a 1-week immersive simulation course. Controls received no simulation training. Primary outcome (at baseline, and 1 and 6 months) was clinical performance on Objective Structured Clinical Examinations (OSCE) of clinical procedures and surgical technical skills. Secondary outcomes were self-reported confidence and clinical procedure logbook data. RESULTS: Nineteen students were recruited. Sixteen completed the 6-month follow-up, 10 in the intervention group and 6 in the control group. No differences were demonstrated between interventions and controls at baseline (OSCE [median, 66 vs. 78; P = .181], technical skills [48 vs. 52.5; P = .381], and confidence [101 vs 96; P = .368]). Interventions outperformed controls at 1 month (OSCE [111 vs 82; P = .001], technical skills [78.5 vs 63; P = .030], and confidence [142 vs. 119; P < .001]), and 6 months (OSCE [107 vs. 93; P = .007], technical skills [92.5 vs. 69; P = .044], and confidence [148 vs. 129; P = .022]). No differences were observed in numbers of clinical procedures performed at 1 (P = .958), 4 (P = .093), or 6 months (P = .713). CONCLUSION: The immersive simulation course objectively improved subjects' clinical skills, technical skills, and confidence. Despite similar clinical experience as controls, the intervention group's improved performance persisted at 6 months follow-up. This feasible and effective intervention to ease transition from student to intern could reduce errors and enhance patient safety.


Assuntos
Competência Clínica , Cirurgia Geral/educação , Internato e Residência , Simulação de Paciente , Seguimentos , Humanos , Segurança do Paciente
14.
J Neurol Neurosurg Psychiatry ; 86(2): 208-15, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24849515

RESUMO

OBJECTIVES: Alemtuzumab is a newly licensed treatment of active relapsing-remitting multiple sclerosis (RRMS) in Europe, which in phase II and III studies demonstrated superior efficacy over ß-interferon in reducing disability progression over 2-3 years. In this observational cohort study, we sought to describe our longer-term experience of the efficacy and safety of alemtuzumab in active RRMS. METHODS: Clinical and laboratory data including serial Expanded Disability Status Scale (EDSS) assessments, from all 87 patients treated with alemtuzumab on investigator-led studies in Cambridge, UK, from 1999 to 2012, were collected. The occurrence of adverse events including secondary autoimmunity, malignancy and death, and pregnancy outcomes was recorded. Baseline variables including age, disease duration and relapse rate were compared in univariate and logistic regression analyses between groups with different disability outcomes. RESULTS: Over a median 7-year follow-up (range 33-144 months), most patients (52%) required just two cycles of alemtuzumab. In the remaining patients, relapses triggered re-treatment to a total of three cycles (36%), four cycles (8%) or five cycles (1%). Using a 6-month sustained accumulation of disability definition, 59/87 (67.8%) of patients had an improved or unchanged disability compared with baseline. By an area under the curve analysis, 52/87 (59.8%) patients had an overall improvement or stabilisation of disability. Higher baseline relapse rate was associated with worse long-term disability outcomes, with trends for longer disease duration and older age at first treatment. Secondary autoimmunity was the most frequent adverse event occurring in 41/86 (47.7%) patients, most commonly involving the thyroid gland. CONCLUSIONS: Alemtuzumab is associated with disease stabilisation in the majority of patients with highly active RRMS over an average seven-year follow-up. No new safety concerns arose over this extended follow-up.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Adolescente , Adulto , Alemtuzumab , Autoimunidade/efeitos dos fármacos , Estudos de Coortes , Avaliação da Deficiência , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento , Adulto Jovem
15.
J Neurol Neurosurg Psychiatry ; 86(7): 708-13, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25246644

RESUMO

OBJECTIVE: There are now a large number of requests for N-methyl-D-aspartate receptor autoantibody (NMDAR-Ab) tests, and it is important to assess the clinical relevance of all results, particularly when they are reported as 'Low Positive'. METHODS: The clinical data of 56 patients found Positive or Low Positive by the Oxford live cell-based assay were reviewed. An autoimmune basis for the condition was assigned as 'Definite', 'Possible' or 'Unlikely'. The number of core features (encephalopathy, psychiatric, cognitive, epileptic, extrapyramidal and inflammatory cerebrospinal fluid (CSF)) was tabulated. RESULTS: Twenty-five (44.6%) patients had a Definite NMDAR-Ab encephalitis (eight ovarian teratomas, one Hodgkin's lymphoma), 18 (32.1%) a Possible NMDAR-Ab encephalitis and 13 (23.2%) an Unlikely autoimmune syndrome. Serum NMDAR-Ab levels were higher in patients with tumours. Positive NMDAR-Abs were found not only in patients with three or more core features and a Definite syndrome, but also in five patients classified as Possible. Conversely, Low Positive NMDAR-Abs were present in 7 Definite cases as well as in 13 Possible cases. Unlikely patients had mainly Low Positive antibodies and fewer core features. CSF NMDAR-Abs, only available in 11 pairs and at varying time points, broadly related to serum levels and were Positive in 3/3 patients with tumours but in only 2/5 Definite patients, and none of the Possible or Unlikely cases. INTERPRETATION: Using live cell-based assays, Positive and Low Positive antibodies can be of clinical significance. The number of core clinical features should help to select those patients in whom an immunotherapy intervention might be considered, irrespective of the antibody level.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico , Autoanticorpos/imunologia , Epitopos/imunologia , Receptores de N-Metil-D-Aspartato/imunologia , Adolescente , Adulto , Encefalite Antirreceptor de N-Metil-D-Aspartato/sangue , Encefalite Antirreceptor de N-Metil-D-Aspartato/imunologia , Autoanticorpos/sangue , Epitopos/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Endócrinas Paraneoplásicas/sangue , Síndromes Endócrinas Paraneoplásicas/diagnóstico , Síndromes Endócrinas Paraneoplásicas/imunologia , Adulto Jovem
17.
Exp Neurol ; 262 Pt A: 37-43, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24792641

RESUMO

The lymphocyte depleting anti-CD52 monoclonal antibody alemtuzumab has been used in Cambridge, UK, as an experimental treatment of multiple sclerosis since 1991. One phase-2 trial (CAMMS-223) and two phase-3 studies (CARE-MS1 and CARE-MS2) have confirmed its efficacy in treatment-naive patients, and have established superiority over interferon beta-1a in patients who continue to relapse in spite of first-line therapy (Cohen et al., 2012; Coles et al., 2008; Coles et al., 2012a; Coles et al., 2012b). Despite causing a prolonged T cell lymphopenia, significant infections have not been an issue following treatment; rather alemtuzumab's primary safety concern is secondary autoimmunity, occurring up to five years after treatment and maximally at two years: 30% of patients develops thyroid autoimmunity, and 1% develops idiopathic thrombocytopenic purpura (ITP). In addition, 4 out of 1486 patients (<0.3%) treated on the commercially sponsored studies developed glomerulonephritis. Two of these patients developed anti-glomerular basement membrane disease, a condition which may result in renal failure unless treated aggressively. In September 2013, the European Medicine Agency (EMA) ruled that the benefit-to-risk balance for alemtuzumab was favourable, approving it as a first-line therapy for adults with active relapsing remitting multiple sclerosis (under the trade name Lemtrada). Lemtrada is now also approved as a treatment of multiple sclerosis in Canada, Australia, Switzerland, Israel, Mexico and Brazil. However, in December 2013, Lemtrada failed to gain approval from the U.S. Food and Drug Administration (FDA), with concerns over trial design and safety stated as the main reasons. In this review we describe our local experience and explain the rationale behind its initial use as a treatment of multiple sclerosis and behind the design of the commercially sponsored trials, summarising their key findings. We also sum up our understanding of its mechanism of action.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antígenos CD/imunologia , Antígenos de Neoplasias/imunologia , Ensaios Clínicos como Assunto , Glicoproteínas/imunologia , Esclerose Múltipla/imunologia , Esclerose Múltipla/terapia , Alemtuzumab , Animais , Antígeno CD52 , Humanos
18.
Brain ; 136(Pt 9): 2888-903, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23864273

RESUMO

Autologous haematopoietic stem cell transplantation has been tried as one experimental strategy for the treatment of patients with aggressive multiple sclerosis refractory to other immunotherapies. The procedure is aimed at ablating and repopulating the immune repertoire by sequentially mobilizing and harvesting haematopoietic stem cells, administering an immunosuppressive conditioning regimen, and re-infusing the autologous haematopoietic cell product. 'Non-myeloablative' conditioning regimens to achieve lymphocytic ablation without marrow suppression have been proposed to improve safety and tolerability. One trial with non-myeloablative autologous haematopoietic stem cell transplantation reported clinical improvement and inflammatory stabilization in treated patients with highly active multiple sclerosis. The aim of the present study was to understand the changes in the reconstituted immune repertoire bearing potential relevance to its mode of action. Peripheral blood was obtained from 12 patients with multiple sclerosis participating in the aforementioned trial and longitudinally followed for 2 years. We examined the phenotype and function of peripheral blood lymphocytes by cell surface or intracellular staining and multi-colour fluorescence activated cell sorting alone or in combination with proliferation assays. During immune reconstitution post-transplantation we observed significant though transient increases in the proportion of CD4+ FoxP3+ T cells and CD56(high) natural killer cell subsets, which are cell subsets associated with immunoregulatory function. CD8+ CD57+ cytotoxic T cells were persistently increased after therapy and were able to suppress CD4+ T cell proliferation with variable potency. In contrast, a CD161(high) proinflammatory CD8+ T cell subset was depleted at all time-points post-transplantation. Phenotypic characterization revealed that the CD161(high)CD8+ T cells were mucosal-associated invariant T cells, a novel cell population originating in the gut mucosa but expressing the central nervous system-homing receptor CCR6. Detection of mucosal-associated invariant T cells in post-mortem multiple sclerosis brain white matter active lesions confirmed their involvement in the disease pathology. Intracellular cytokine staining demonstrated interferon γ and interleukin 17 production and lack of interleukin 10 production, a pro-inflammatory profile. Mucosal-associated invariant T cell frequency did not change in patients treated with interferon ß; and was more depleted after autologous haematopoietic stem cell transplantation than in patients who had received high-dose cyclophosphamide (n = 7) or alemtuzumab (n = 21) treatment alone, suggesting an additive or synergistic effect of the conditioning regime components. We propose that a favourably modified balance of regulatory and pro-inflammatory lymphocytes underlies the suppression of central nervous system inflammation in patients with multiple sclerosis following non-myeloablative autologous haematopoietic stem cell transplantation with a conditioning regimen consisting of cyclophosphamide and alemtuzumab.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Interleucina-17/metabolismo , Esclerose Múltipla/patologia , Esclerose Múltipla/cirurgia , Linfócitos T Reguladores/imunologia , Adulto , Análise de Variância , Encéfalo/metabolismo , Encéfalo/patologia , Ciclofosfamida/uso terapêutico , Citocinas/metabolismo , Feminino , Citometria de Fluxo , Granzimas/metabolismo , Humanos , Imunossupressores/uso terapêutico , Antígeno Ki-67/metabolismo , Estudos Longitudinais , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Mucosa/metabolismo , Mucosa/patologia , Esclerose Múltipla/tratamento farmacológico , Perforina/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T Reguladores/classificação , Adulto Jovem
19.
Br J Community Nurs ; 18(4 Suppl): S6-S11, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23752217

RESUMO

Due to developments in diagnosis and treatment of breast cancer, survival rates are rising. This leads to a population of mainly women, who also experience breast cancer-related lymphoedema (BCRL). Long after the cancer has been treated, lymphoedema persists at a time when individuals have returned to work. Large limb volumes can present a problem to these individuals and innovative treatments are needed, in order to retain as much normality as possible and reduce excessive limb volumes that patients can experience with lymphoedema long after treatment. It is also important that these treatments do not disrupt daily living and, for some, work-life balance. With the introduction of wrap around compression systems and collaborative working with the patient, it is possible to achieve an acceptable outcome to those patients with these issues. This approach leads to patient satisfaction and stabilisation of limb volume to within acceptable limits for these patients, in conjunction with the therapist.


Assuntos
Neoplasias da Mama , Linfedema , Bandagens Compressivas , Humanos , Linfedema/terapia
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