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1.
Zootaxa ; 5352(1): 73-108, 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-38221459

RESUMEN

Litoria rothii is a widespread pelodryadid frog with a charismatic laughing advertisement call, distributed across the Australian Monsoon Tropics and southern New Guinea. Given its large distribution spanning well-known biogeographic barriers, variation in male advertisement calls and the prevalence of unresolved species complexes in the Australian frog fauna, we examine the genetic, morphological and acoustic diversity in the species from across its range. Our analyses reveal the presence of a previously unrecognised species in western parts of the range of L. rothii sensu lato, which we describe herein as a new species. Litoria ridibunda sp. nov. is distinguished from L. rothii on the basis of paraphyly of nuclear gene trees with L. everetti from Indonesia, colour patterns on the posterior thigh and male advertisement calls. Compared to L. rothii, the new species has a less contrasting pattern on the posterior thigh and a male advertisement call with a greater number of notes per call and a greater call duration. In particular, the magnitude of call differences between the species is highest where the ranges of the two species are in proximity in north-western Queensland. Our study further emphasises the undiagnosed diversity that remains in Australian frogs, even in relatively large, charismatic, frequently encountered species that often share human dwellings.


Asunto(s)
Anuros , Humanos , Animales , Australia , Anuros/genética , Anuros/anatomía & histología , Filogenia
2.
Mater Today Bio ; 8: 100080, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33205040

RESUMEN

New strategies for immune modulation have shown real promise in regenerative medicine as well as the fight against autoimmune diseases, allergies, and cancer. Dendritic cells (DCs) are gatekeepers of the immune system and their ability in shaping the adaptive immune responses makes DCs ideal targets for immune modulation. Carbohydrates are abundant in different biological systems and are known to modulate DC phenotype and function. However, how simple monosaccharides instruct DC function is less well understood. In this study, we used a combinatorial array of immobilized monosaccharides to investigate how they modulate DC phenotype and function and crucially the impact of such changes on downstream adaptive immune responses. Our data show that a selection of monosaccharides significantly suppress lipopolysaccharide-induced DC activation as evidenced by a reduction in CD40 expression, IL-12 production, and indoleamine 2,3-dioxygenase activity, while inducing a significant increase in IL-10 production. These changes are indicative of the induction of an anti-inflammatory or regulatory phenotype in DCs, which was further confirmed in DC-T cell co-cultures where DCs cultured on the 'regulatory' monosaccharide-coated surfaces were shown to induce naïve T cell polarization toward regulatory phenotype. Our data also highlighted a selection of monosaccharides that are able to promote mixed Treg and Th17 cell differentiation, a T cell phenotype expected to be highly immune suppressive. These data show the potential immunomodulatory effects of immobilized monosaccharides in priming DCs and skewing T cell differentiation toward an immune-regulatory phenotype. The ability to fine-tune immune responses using these simple carbohydrate combinations (e.g. as coatings for existing materials) can be utilized as novel tools for immune modulation with potential applications in regenerative medicine, implantable medical devices, and wound healing where reduction of inflammatory responses and maintaining immune homeostasis are desirable.

3.
Biomater Sci ; 5(4): 707-717, 2017 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-28184390

RESUMEN

PEGylated gold nanoparticles (AuNPs) have an extended circulation time after intravenous injection in vivo and exhibit favorable properties for biosensing, diagnostic imaging, and cancer treatment. No impact of PEGylated AuNPs on the barrier forming properties of endothelial cells (ECs) has been reported, but recent studies demonstrated that unexpected effects on erythrocytes are observed. Almost all studies to date have been with static-cultured ECs. Herein, ECs maintained under physiological cyclic stretch and flow conditions and used to generate a blood-brain barrier model were exposed to 20 nm PEGylated AuNPs. An evaluation of toxic effects, cell stress, the release profile of pro-inflammatory cytokines, and blood-brain barrier properties showed that even under physiological conditions no obvious effects of PEGylated AuNPs on ECs were observed. These findings suggest that 20 nm-sized, PEGylated AuNPs may be a useful tool for biomedical applications, as they do not affect the normal function of healthy ECs after entering the blood stream.


Asunto(s)
Células Endoteliales/efectos de los fármacos , Oro/metabolismo , Nanopartículas/metabolismo , Polietilenglicoles/metabolismo , Animales , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Células Cultivadas , Células Endoteliales/metabolismo , Células Endoteliales/patología , Oro/química , Oro/toxicidad , Células Endoteliales de la Vena Umbilical Humana , Humanos , Nanopartículas/química , Nanopartículas/toxicidad , Tamaño de la Partícula , Polietilenglicoles/química , Polietilenglicoles/toxicidad , Porcinos
4.
Zootaxa ; 4072(3): 319-32, 2016 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-27395927

RESUMEN

Three distinctive new species of Papuagrion Ris, 1913 are described from a high altitude area (1,770-1,820 m a.s.l.) at the base of the Hindenburg Wall, Western Province, Papua New Guinea. These are P. chrysosoma sp. nov., P marijanmatoki sp. nov. and P. tydecksjuerging sp. nov.; all type material is deposited in the South Australian Museum (SAMA). These were the only species of the genus collected at higher altitudes in the Ok Tedi headwaters, and none of them were encountered at lower altitudes (300-900 m) despite intensive searches there. The new species described here bring to 26 the number of Papuagrion species known from the New Guinea region.


Asunto(s)
Odonata/anatomía & histología , Odonata/clasificación , Altitud , Animales , Ecosistema , Femenino , Masculino , Nueva Guinea
5.
Zootaxa ; 3990(3): 429-36, 2015 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-26250243

RESUMEN

A new genus and species belonging to the damselfly subfamily Idiocnemidinae from Papua New Guinea, Macrocnemis gracilis gen. nov. sp. nov. is described and illustrated. It is the largest known member of the Papuan idiocnemidine radiation, and its affinities to existing genera remain unclear. The new taxon is currently known with certainty only from small streams flowing through mid-montane rainforest in the Hindenburg Range of Papua New Guinea's rugged central cordillera.


Asunto(s)
Odonata/clasificación , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Ecosistema , Femenino , Masculino , Odonata/anatomía & histología , Odonata/crecimiento & desarrollo , Tamaño de los Órganos , Papúa Nueva Guinea
6.
Zootaxa ; 3866(1): 145-50, 2014 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-25283653

RESUMEN

Drepanosticta machadoi sp. nov. (Holotype ♂: Dablin Creek, Hindenburg Range) from Papua New Guinea is described. The new species is a predominantly black damselfly, the male with four pale/bright pattern elements on each side of the synthorax, dorsum of segments 9 and 10 largely bright blue, and a uniquely shaped posterior lobe of the pronotum which is a wide-angled fork with rather straight, narrow finger-like prongs. It is referred to the Drepanosticta conica group of species and a key to the males of the D. conica group is provided.


Asunto(s)
Odonata/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Ecosistema , Masculino , Nueva Guinea , Odonata/anatomía & histología , Odonata/crecimiento & desarrollo , Tamaño de los Órganos , Papúa Nueva Guinea
7.
Leukemia ; 26(7): 1730-41, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22307178

RESUMEN

Flow cytometry (FC) is increasingly recognized as an important tool in the diagnosis and prognosis of myelodysplastic syndromes (MDS). However, validation of current assays and agreement upon the techniques are prerequisites for its widespread acceptance and application in clinical practice. Therefore, a working group was initiated (Amsterdam, 2008) to discuss and propose standards for FC in MDS. In 2009 and 2010, representatives from 23, mainly European, institutes participated in the second and third European LeukemiaNet (ELN) MDS workshops. In the present report, minimal requirements to analyze dysplasia are refined. The proposed core markers should enable a categorization of FC results in cytopenic patients as 'normal', 'suggestive of', or 'diagnostic of' MDS. An FC report should include a description of validated FC abnormalities such as aberrant marker expression on myeloid progenitors and, furthermore, dysgranulopoiesis and/or dysmonocytopoiesis, if at least two abnormalities are evidenced. The working group is dedicated to initiate further studies to establish robust diagnostic and prognostic FC panels in MDS. An ultimate goal is to refine and improve diagnosis and prognostic scoring systems. Finally, the working group stresses that FC should be part of an integrated diagnosis rather than a separate technique.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Citometría de Flujo/normas , Síndromes Mielodisplásicos/diagnóstico , Síndromes Mielodisplásicos/metabolismo , Guías de Práctica Clínica como Asunto/normas , Médula Ósea/metabolismo , Médula Ósea/patología , Citometría de Flujo/métodos , Humanos , Inmunofenotipificación , Agencias Internacionales , Síndromes Mielodisplásicos/inmunología , Pronóstico , Estándares de Referencia , Sociedades Científicas
8.
Oncogene ; 29(20): 2927-37, 2010 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-20208555

RESUMEN

Correct hematopoietic differentiation requires the tightly regulated execution of lineage-specific and stage-restricted gene expression programs. This process is disturbed in hematological malignancies that typically show incomplete differentiation but often also display a mixed lineage phenotype. Co-expression of lymphoid and myeloid molecules is a well-known feature of acute myeloblastic leukemia (AML) with t(8;21). These cells consistently express the B-cell-specific transcription factor PAX5, and the B-cell-specific cell surface protein CD19. However, the functional consequences of PAX5 expression are unknown. To address this question, we studied the chromatin features of CD19, which is a direct target of PAX5 in cells with and without the t(8;21) chromosomal translocation. We show that CD19 chromatin exists in a poised configuration in myeloid progenitors and that this poised chromatin structure facilitates PAX5-dependent CD19 activation. Our results also show a positive correlation between PAX5 and CD19 expression in t(8;21)-positive AML cells and demonstrate that PAX5 binds to the promoter and enhancer of CD19 gene and remodels chromatin structure at the promoter. This study shows that expression of PAX5 in leukemic cells has functional consequences and points to an important role of a progenitor-specific chromatin configuration in myeloid leukemia.


Asunto(s)
Antígenos CD19/genética , Cromatina/química , Cromosomas Humanos Par 21/genética , Cromosomas Humanos Par 8/genética , Leucemia Mieloide Aguda/genética , Factor de Transcripción PAX5/genética , Translocación Genética/genética , Antígenos CD19/metabolismo , Linfocitos B/metabolismo , Linfocitos B/patología , Cromatina/fisiología , Inmunoprecipitación de Cromatina , Huella de ADN , Elementos de Facilitación Genéticos , Citometría de Flujo , Regulación Leucémica de la Expresión Génica , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Regiones Promotoras Genéticas , Células Tumorales Cultivadas
9.
J Med Microbiol ; 58(Pt 8): 977-987, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19528155

RESUMEN

As antibiotic resistance increases worldwide, there is an increasing pressure to develop novel classes of antimicrobial compounds to fight infectious disease. Peptide therapeutics represent a novel class of therapeutic agents. Some, such as cationic antimicrobial peptides and peptidoglycan recognition proteins, have been identified from studies of innate immune effector mechanisms, while others are completely novel compounds generated in biological systems. Currently, only selected cationic antimicrobial peptides have been licensed, and only for topical applications. However, research using new approaches to identify novel antimicrobial peptide therapeutics, and new approaches to delivery and improving stability, will result in an increased range of peptide therapeutics available in the clinic for broader applications.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Proteínas Portadoras/uso terapéutico , Humanos , Conformación Proteica
10.
QJM ; 101(4): 299-306, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18287112

RESUMEN

BACKGROUND: Immunological tolerance in humans using anti-T-cell monoclonal antibodies (mAbs) may be hampered by a pro-inflammatory microenvironment. All clinical trials of such therapies in rheumatoid arthritis (RA), however, have selected patients with active disease at baseline. Concurrent neutralization of inflammation with a TNFalpha antagonist should maximize the potential of anti-T-cell mAbs to induce tolerance in RA. AIM: To evaluate the safety of combining a TNFalpha antagonist and CD4 mAb in RA. DESIGN: An iterative pilot study focused on the safety of such combination therapy. METHODS: Eight poor prognosis, seropositive RA patients were treated with combined CD4 and TNFalpha blockade. Prolonged CD4 blockade was achieved with a humanized mAb, and TNFalpha blockade with a p55 TNF receptor fusion protein. RESULTS: There was a low incidence of classical first-dose reactions to the CD4 mAb, possibly reflecting concomitant TNFalpha blockade. An unusual anaphylactoid reaction was seen, however, and one patient developed a probable allergic reaction after several infusions. Skin rashes were common, as previously reported with CD4 mAb monotherapy. No serious infections were documented during follow-up, despite CD4+ lymphopenia in some patients. Most patients appeared to demonstrate improved RA disease control after the study. After 17-49 months after therapy, one patient was in remission, one remained off disease modifying anti-rheumatic drugs and five had stable disease, three on previously ineffective doses of methotrexate. CONCLUSION: We report, for the first time in man, immunotherapy with a combination of an anti-cytokine and an anti-T-cell reagent. We witnessed an unusual first-dose reaction but there were no significant infectious complications.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Antígenos CD4/uso terapéutico , Linfocitos/inmunología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Adulto , Relación Dosis-Respuesta a Droga , Quimioterapia Combinada , Femenino , Humanos , Factores Inmunológicos/uso terapéutico , Masculino , Persona de Mediana Edad , Proyectos Piloto , Resultado del Tratamiento
11.
Haematologica ; 92(3): e31-3, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17405753

RESUMEN

Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by intravascular hemolysis leading to anemia and other clinical manifestations. Transfusions are often required to support hemoglobin at tolerable levels. A PNH patient with aplastic anemia was treated with the complement inhibitor eculizumab, followed by concurrent treatment with recombinant human erythropoietin (rHuEpo). Eculizumab alone reduced hemolysis, increased PNH red blood cell (RBC) mass, and decreased transfusions. Addition of rHuEpo during eculizumab therapy, enhanced erythropoiesis, further increased PNH RBC mass and hemoglobin levels, and rendered the patient transfusion independent for more than two years. These data show that driving erythropoiesis during eculizumab treatment provided further benefit to a patient with PNH and underlying bone marrow failure.


Asunto(s)
Anemia Aplásica/tratamiento farmacológico , Anticuerpos Monoclonales/uso terapéutico , Complemento C5/antagonistas & inhibidores , Eritropoyesis/efectos de los fármacos , Eritropoyetina/farmacología , Hemoglobinuria Paroxística/tratamiento farmacológico , Hemólisis/efectos de los fármacos , Anemia Aplásica/sangre , Anemia Aplásica/etiología , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales Humanizados , Transfusión Sanguínea , Complemento C5/inmunología , Sinergismo Farmacológico , Índices de Eritrocitos/efectos de los fármacos , Eritropoyetina/uso terapéutico , Hemoglobinas/análisis , Hemoglobinuria Paroxística/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes , Resultado del Tratamiento
13.
Bioorg Med Chem Lett ; 14(21): 5395-9, 2004 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-15454233
14.
Clin Lab Haematol ; 26(1): 37-42, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14738436

RESUMEN

The diagnosis of plasma cell leukaemia, a rare disorder with an aggressive clinical course and poor prognosis, is not always straightforward and may be dependent on the results of immunophenotyping. Samples from two cases of plasma cell leukaemia have been issued by the UK NEQAS for Leucocyte Immunophenotyping Scheme during the last 5 years and on each occasion a significant number of laboratories failed to make the correct diagnosis. The details of the two samples issued and the results of both surveys are presented. The data highlights the need to adhere to guidelines for immunophenotyping, with respect to using the correct antibody panels, the importance of data interpretation in conjunction with morphological appearance as well as the need to participate in external quality assurance schemes.


Asunto(s)
Técnicas de Laboratorio Clínico/normas , Adhesión a Directriz/normas , Inmunofenotipificación/métodos , Leucemia de Células Plasmáticas/diagnóstico , Leucocitos/inmunología , Antígenos de Superficie/inmunología , Femenino , Humanos , Leucemia de Células Plasmáticas/inmunología , Recuento de Leucocitos , Subgrupos Linfocitarios/inmunología , Masculino , Guías de Práctica Clínica como Asunto/normas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
15.
Clin Lab Haematol ; 25(6): 337-42, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14641135

RESUMEN

The diagnosis and monitoring of leukaemia and lymphoma requires the effective integration of a wide range of diagnostic techniques and expertise. The need to develop this type of service that crosses traditional boundaries of laboratory specialities is being recommended in national guidance. The Haematological Malignancy Diagnostic Service based within the Leeds Teaching Hospitals NHS Trust was established in 1993 to provide specialist laboratory services for the diagnosis of haematological malignancy for Yorkshire and Humberside in the UK. The department uses a wide range of methodologies including morphology, immunocytochemistry, flow cytometry and molecular genetics [fluorescent in situ hybridization (FISH) and polymerase chain reaction (PCR)] in a systematic and co-ordinated way. We describe how the department was established, its current working practices and highlight the advantages of an integrated laboratory for diagnosis of tumours of the haematopoietic system.


Asunto(s)
Prestación Integrada de Atención de Salud/organización & administración , Pruebas Hematológicas , Laboratorios/organización & administración , Leucemia/diagnóstico , Linfoma/diagnóstico , Algoritmos , Pruebas Diagnósticas de Rutina , Inglaterra , Predicción , Humanos , Laboratorios/normas , Personal de Laboratorio Clínico/educación , Sistemas de Registros Médicos Computarizados/organización & administración , Investigación
16.
Curr Med Chem ; 10(2): 99-121, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12570713

RESUMEN

Type 2 diabetes is a widespread disease where effective pharmacologic therapies can have a profound beneficial public health impact. Increased hepatic glucose production (HGP) is observed in diabetics and its moderation by currently available agents provides therapeutic benefits. This review describes the challenges associated with the discovery of small molecules that inhibit HGP. Gluconeogenesis, glycogenolysis, liver architecture, and hepatocyte composition are described to provide background information on hepatic function. Current methods of target validation for drug discovery, HGP measurement, diabetes animal models, as well as current drug therapies are covered. In the accompanying review article the new drug targets being probed to produce the next generation of therapies are described. Significant pharmaceutical and academic efforts to pharmacologically inhibit HGP has the opportunity to provide new therapeutics for type 2 diabetics.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Glucosa/biosíntesis , Hipoglucemiantes/farmacología , Hígado/efectos de los fármacos , Hígado/metabolismo , Animales , Proteínas Portadoras/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Circulación Enterohepática/efectos de los fármacos , Humanos , Receptores Citoplasmáticos y Nucleares/agonistas , Receptores Citoplasmáticos y Nucleares/antagonistas & inhibidores , Factores de Transcripción/agonistas , Factores de Transcripción/antagonistas & inhibidores
17.
Curr Med Chem ; 10(2): 123-53, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12570714

RESUMEN

A number of therapeutic targets are currently under investigation for inhibition of hepatic glucose production with small molecules. Antagonists of the glucagon receptor, glycogen phosphorylase, 11-beta-hydroxysteroid dehydrogenase-1 and fructose 1,6-bisphosphatase are, or have been, under evaluation in human clinical trials. Other strategies, including glucocorticoid receptor antagonists and carnitine palmitoyltransferase inhibitors, are supported by proof of principle studies in man as well as rodents. Several potential targets including glucose-6-phosphatase, glucose-6-phosphatase translocase, glycogen synthase kinase-3, adenosine receptor 2B antagonists, phosphoenolpyruvate carboxykinase and pyruvate dehydrogenase kinase, have been validated by compounds that are effective in animal models. Other targets like PGC-1a and CREB have initial validation support but no medicinal chemistry has been reported.


Asunto(s)
Glucosa/biosíntesis , Hígado/efectos de los fármacos , Hígado/metabolismo , Animales , Depresión Química , Humanos
18.
Am J Clin Pathol ; 116(3): 420-8, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11554171

RESUMEN

To establish whether a combination of morphologic and immunophenotypic criteria could be developed to more precisely define Waldenström macroglobulinemia (WM) and prognostic factors, we retrospectively assessed the clinical and laboratory features of 111 cases of WM. Bone marrow infiltration by small lymphocytes was documented in each case; and diffuse, interstitial, nodular, and paratrabecular patterns of infiltration were documented in 58%, 32%, 6%, and 4% of cases, respectively. Ninety percent were characterized by a surface immunoglobulin-positive, CD19+CD20+CD5-CD10-CD23- immunophenotype. The median overall survival from diagnosis was 60 months; univariate analysis revealed the following adverse prognostic factors: older than 60 years, performance status more than 1, platelet count less than 100 x 10(3)/microL (< 100 x 10(9)/L), pancytopenia, and diffuse bone marrow infiltration. Associated median survival was 40, 38, 46, 28, and 59 months, respectively. Multivariate analysis revealed age, performance status, and platelet count as prognostically significant, but stratification of patients according to the International Prognostic Index had limited value. We suggest defining WM by the following criteria: IgM monoclonal gammopathy; bone marrow infiltration by small lymphocytes, plasmacytoid cells, and plasma cells in a diffuse, interstitial, or nodular pattern; and a surface immunoglobulin-positive, CD19+CD20+CD5-CD10-CD23- immunophenotype.


Asunto(s)
Macroglobulinemia de Waldenström/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Antígenos CD/análisis , Médula Ósea/inmunología , Médula Ósea/patología , Femenino , Citometría de Flujo , Humanos , Inmunofenotipificación , Masculino , Persona de Mediana Edad , Pronóstico , Tasa de Supervivencia , Macroglobulinemia de Waldenström/inmunología , Macroglobulinemia de Waldenström/mortalidad
19.
Blood ; 98(1): 29-35, 2001 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-11418459

RESUMEN

Previous studies have suggested that the level of residual disease at the end of therapy predicts outcome in chronic lymphocytic leukemia (CLL). However, available methods for detecting CLL cells are either insensitive or not routinely applicable. A flow cytometric assay was developed that can differentiate CLL cells from normal B cells on the basis of their CD19/CD5/CD20/CD79b expression. The assay is rapid and can detect one CLL cell in 10(4) to 10(5) leukocytes in all patients. We have compared this assay to conventional assessment in 104 patients treated with CAMPATH-1H and/or autologous transplant. During CAMPATH-1H therapy, circulating CLL cells were rapidly depleted in responding patients, but remained detectable in nonresponders. Patients with more than 0.01 x 10(9)/L circulating CLL cells always had significant (> 5%) marrow disease, and blood monitoring could be used to time marrow assessments. In 25 out of 104 patients achieving complete remission by National Cancer Institute (NCI) criteria, the detection of residual bone marrow disease at more than 0.05% of leukocytes in 6 out of 25 patients predicted significantly poorer event-free (P =.0001) and overall survival (P =.007). CLL cells are detectable at a median of 15.8 months (range, 5.5-41.8) posttreatment in 9 out of 18 evaluable patients with less than 0.05% CLL cells at end of treatment. All patients with detectable disease have progressively increasing disease levels on follow-up. The use of sensitive techniques, such as the flow assay described here, allow accurate quantitation of disease levels and provide an accurate method for guiding therapy and predicting outcome. These results suggest that the eradication of detectable disease may lead to improved survival and should be tested in future studies.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/diagnóstico , Neoplasia Residual/diagnóstico , Adulto , Anciano , Alemtuzumab , Anticuerpos , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Anticuerpos Antineoplásicos/farmacología , Anticuerpos Antineoplásicos/uso terapéutico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Linfocitos B/inmunología , Células Sanguíneas/patología , Médula Ósea/patología , Femenino , Citometría de Flujo , Trasplante de Células Madre Hematopoyéticas , Humanos , Inmunofenotipificación , Leucemia Linfocítica Crónica de Células B/terapia , Masculino , Persona de Mediana Edad , Pronóstico , Sensibilidad y Especificidad , Resultado del Tratamiento
20.
Br J Haematol ; 113(3): 794-802, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11380472

RESUMEN

The nature of the proliferating fraction in myeloma is still not known and understanding the characteristics of this fraction is central to the development of effective novel therapies. However, myeloma plasma cells typically show a very low rate of proliferation and this complicates accurate analysis. Although the level of CD45 and/or VLA-5 has been reported to identify proliferating 'precursor' plasma cells, there are discrepancies between these studies. We have therefore used a rigorous sequential gating strategy to simultaneously analyse cycle status and immunophenotype with respect to CD45, VLA-5 and a range of other integrin molecules. In 11 presentation myeloma patients, the proliferative fraction was distributed evenly between CD45+ and CD45- cells, however, cycling plasma cells were consistently VLA-5-. There was close correlation between the expression of VLA-5 and a range of other integrin molecules (CD11a, CD11c, CD103), as well as the immunoglobulin-associated molecules CD79a/b (Spearman, n = 10, P < 0.0001). In short-term culture, cells that were initially VLA-5-showed increasing VLA-5 expression with time. However, simultaneous analysis of the DNA-binding dye 7-amino-actinomycin D demonstrated that this was not as a result of differentiation, as VLA-5+ plasma cells were all non-viable. This was confirmed in freshly explanted plasma cells from nine patients. Discrete stages of plasma cell differentiation could not be distinguished by the level of CD45 or VLA-5 expression. The results indicate that there is a single stage of plasma cell differentiation, with the phenotype CD38+CD138+VLA-5-. These findings support the hypothesis that neoplastic bone marrow plasma cells represent an independent, self-replenishing population.


Asunto(s)
Cadenas alfa de Integrinas , Antígenos Comunes de Leucocito/análisis , Mieloma Múltiple/patología , Células Plasmáticas/patología , Receptores de Fibronectina/análisis , Antígenos CD/análisis , Biomarcadores de Tumor/análisis , Antígenos CD79 , Diferenciación Celular , División Celular , Citometría de Flujo , Humanos , Inmunofenotipificación , Antígeno-1 Asociado a Función de Linfocito/análisis , Mieloma Múltiple/inmunología , Mieloma Múltiple/metabolismo , Células Plasmáticas/química , Células Plasmáticas/inmunología , Células Tumorales Cultivadas
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