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1.
Ann Rheum Dis ; 2022 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-35798534

RESUMEN

OBJECTIVE: Evaluate the efficacy and safety of ustekinumab, an anti-interleukin-12/23 p40 antibody, in a phase 3, randomised, placebo-controlled study of patients with active systemic lupus erythematosus (SLE) despite receiving standard-of-care. METHODS: Active SLE patients (SLE Disease Activity Index 2000 (SLEDAI-2K) ≥6 during screening and SLEDAI-2K ≥4 for clinical features at week 0) despite receiving oral glucocorticoids, antimalarials, or immunomodulatory drugs were randomised (3:2) to receive ustekinumab (intravenous infusion ~6 mg/kg at week 0, followed by subcutaneous injections of ustekinumab 90 mg at week 8 and every 8 weeks) or placebo through week 48. The primary endpoint was SLE Responder Index (SRI)-4 at week 52, and major secondary endpoints included time to flare through week 52 and SRI-4 at week 24. RESULTS: At baseline, 516 patients were randomised to placebo (n=208) or ustekinumab (n=308). Following the planned interim analysis, the sponsor discontinued the study due to lack of efficacy but no safety concerns. Efficacy analyses included 289 patients (placebo, n=116; ustekinumab, n=173) who completed or would have had a week 52 visit at study discontinuation. At week 52, 44% of ustekinumab patients and 56% of placebo patients had an SRI-4 response; there were no appreciable differences between the treatment groups in the major secondary endpoints. Through week 52, 28% of ustekinumab patients and 32% of placebo patients had a British Isles Lupus Assessment Group flare, with a mean time to first flare of 204.7 and 200.4 days, respectively. Through week 52, 70% of ustekinumab patients and 74% of placebo patients had ≥1 adverse event. CONCLUSIONS: Ustekinumab did not demonstrate superiority over placebo in this population of adults with active SLE; adverse events were consistent with the known safety profile of ustekinumab. TRIAL REGISTRATION NUMBER: NCT03517722.

2.
Ann Rheum Dis ; 76(12): 2001-2008, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28855173

RESUMEN

OBJECTIVES: Interleukin-6 (IL-6) is implicated in rheumatoid arthritis (RA) pathophysiology. Unlike IL-6 receptor inhibitors, sirukumab is a human monoclonal antibody that selectively binds to the IL-6 cytokine. The phase III, multicentre, randomised, double-blind, placebo-controlled, parallel-group SIRROUND-D study (ClinicalTrials.gov identifier NCT01604343) evaluated the efficacy and safety of sirukumab in patients with active RA refractory to disease-modifying antirheumatic drugs. METHODS: Patients were randomised 1:1:1 to treatment with sirukumab 100 mg every 2 weeks, 50 mg every 4 weeks or placebo every 2 weeks subcutaneously. Results through week 52 are reported. RESULTS: Of 1670 randomised patients, significantly more patients achieved American College of Rheumatology 20% (ACR20) response at week 16 (coprimary endpoint) with sirukumab 100 mg every 2 weeks (53.5%) or 50 mg every 4 weeks (54.8%) versus placebo (26.4%; both p<0.001). Mean (SD) change from baseline in modified Sharp/van der Heijde score at week 52 (coprimary endpoint) was significantly lower with sirukumab (100 mg every 2 weeks: 0.46 (3.26); 50 mg every 4 weeks: 0.50 (2.96)) versus placebo (3.69 (9.25); both p<0.001). All major secondary endpoints (week 24 Health Assessment Questionnaire-Disability Index change from baseline, ACR50 response, 28-joint Disease Activity Score based on C reactive protein and major clinical response (ACR70 for six continuous months by week 52)) were met. The most common adverse events with sirukumab were elevated liver enzymes, upper respiratory tract infection, injection site erythema and nasopharyngitis. CONCLUSIONS: Sirukumab 100 mg every 2 weeks and 50 mg every 4 weeks led to significant reductions in RA symptoms, inhibition of structural damage progression and physical function and quality of life improvements, with an expected safety profile. TRIAL REGISTRATION NUMBER: NCT01604343; Results.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Antirreumáticos/administración & dosificación , Artritis Reumatoide/tratamiento farmacológico , Adulto , Anciano , Anticuerpos Monoclonales Humanizados , Artritis Reumatoide/sangre , Proteína C-Reactiva/análisis , Método Doble Ciego , Femenino , Humanos , Interleucina-6/sangre , Masculino , Persona de Mediana Edad , Calidad de Vida , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
3.
Rheumatology (Oxford) ; 53(9): 1654-63, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24729398

RESUMEN

OBJECTIVE: The aim of this study was to assess the efficacy and safety of golimumab in Chinese patients with active AS. METHODS: Two hundred and thirteen patients were randomized in a 1:1 ratio to receive either s.c. injections of placebo from weeks 0 to 20 followed by golimumab 50 mg from weeks 24 to 48 (group 1, n = 105) or golimumab 50 mg from weeks 0 to 48 (group 2, n = 108), both every 4 weeks. Placebo crossover occurred at week 24, while early escape was at week 16. The primary endpoint was an improvement of at least 20% in the Assessment of SpondyloArthritis international Society (ASAS20) criteria at week 14. Major secondary endpoints included week 24 ASAS20 response and week 14 change scores for BASFI and BASMI. RESULTS: Golimumab treatment elicited significantly better responses than placebo in week 14 ASAS20 response [49.1% (53/108) vs 24.8% (26/105), respectively, P < 0.001], week 24 ASAS20 response (50.0% vs 22.9%, P < 0.001) and mean improvements in BASFI (-1.26 vs 0.11, P < 0.001) and BASMI (-0.42 vs -0.19, P = 0.021) scores at week 14. Additionally, golimumab treatment led to significant improvements in the mental and physical components of health-related quality of life (HRQoL) and sleep problems at week 24, all of which were further improved through week 52. During the 16-week placebo-controlled study period, 31.4% and 30.6% of patients had adverse events (AEs) in groups 1 and 2, respectively; similar AE reporting rates were observed through week 24 (34.3% and 32.0%) and among the golimumab-treated patients through week 56 (41.2%). CONCLUSION: Golimumab significantly reduced clinical symptoms/signs and improved physical function, range of motion and HRQoL in Chinese patients with active AS without unexpected safety concerns. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01248793.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antirreumáticos/uso terapéutico , Espondilitis Anquilosante/tratamiento farmacológico , Adulto , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/sangre , Antirreumáticos/efectos adversos , Antirreumáticos/sangre , Método Doble Ciego , Femenino , Humanos , Inyecciones Subcutáneas , Masculino , Calidad de Vida , Índice de Severidad de la Enfermedad , Espondilitis Anquilosante/sangre , Espondilitis Anquilosante/rehabilitación , Resultado del Tratamiento , Adulto Joven
4.
RMD Open ; 10(2)2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38942592

RESUMEN

OBJECTIVES: To investigate the efficacy, safety, pharmacokinetics and pharmacodynamics of nipocalimab in participants with moderate to severe active rheumatoid arthritis (RA) and inadequate response or intolerance to ≥1 antitumour necrosis factor agent. METHODS: In this phase 2a study, participants with RA seropositive for anticitrullinated protein antibodies (ACPA) or rheumatoid factors were randomised 3:2 to nipocalimab (15 mg/kg intravenously every 2 weeks) or placebo from Weeks 0 to 10. Efficacy endpoints (primary endpoint: change from baseline in Disease Activity Score 28 using C reactive protein (DAS28-CRP) at Week 12) and patient-reported outcomes (PROs) were assessed through Week 12. Safety, pharmacokinetics and pharmacodynamics were assessed through Week 18. RESULTS: 53 participants were enrolled (nipocalimab/placebo, n=33/20). Although the primary endpoint did not reach statistical significance for nipocalimab versus placebo, a numerically higher change from baseline in DAS28-CRP at Week 12 was observed (least squares mean (95% CI): -1.03 (-1.66 to -0.40) vs -0.58 (-1.24 to 0.07)), with numerically higher improvements in all secondary efficacy outcomes and PROs. Serious adverse events were reported in three participants (burn infection, infusion-related reaction and deep vein thrombosis). Nipocalimab significantly and reversibly reduced serum immunoglobulin G, ACPA and circulating immune complex levels but not serum inflammatory markers, including CRP. ACPA reduction was associated with DAS28-CRP remission and 50% response rate in American College of Rheumatology (ACR) criteria; participants with a higher baseline ACPA had greater clinical improvement. CONCLUSIONS: Despite not achieving statistical significance in the primary endpoint, nipocalimab showed consistent, numerical efficacy benefits in participants with moderate to severe active RA, with greater benefit observed for participants with a higher baseline ACPA. TRIAL REGISTRATION NUMBER: NCT04991753.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Antirreumáticos , Artritis Reumatoide , Índice de Severidad de la Enfermedad , Humanos , Artritis Reumatoide/tratamiento farmacológico , Masculino , Femenino , Persona de Mediana Edad , Resultado del Tratamiento , Antirreumáticos/uso terapéutico , Antirreumáticos/administración & dosificación , Antirreumáticos/efectos adversos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anciano , Adulto , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Método Doble Ciego , Medición de Resultados Informados por el Paciente , Anticuerpos Antiproteína Citrulinada/sangre
5.
Headache ; 52(2): 224-35, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22221076

RESUMEN

OBJECTIVE: To evaluate the efficacy of telcagepant in patients with migraine and coronary artery disease. BACKGROUND: Calcitonin gene-related peptide receptor antagonists, such as telcagepant, may be useful for acute migraine treatment in patients with cardiovascular disease, a population for whom triptans are contraindicated. METHODS: Randomized, double-blind, two-period (6 weeks per period) crossover study in patients with stable coronary artery disease and migraine. Patients were randomized 1:1 to either: (1) Period 1: telcagepant (280-mg tablet/300-mg capsule), Period 2: acetaminophen (1000-mg); or (2) Period 1: placebo for attack 1 then acetaminophen for subsequent attacks, Period 2: telcagepant. Patients could treat up to 12 migraine attacks per period to assess the tolerability of telcagepant. The primary efficacy analysis evaluated telcagepant vs placebo on 2-hour pain freedom during the first attack of Period 1. RESULTS: One hundred and sixty-five of the planned 400 patients were enrolled, and 114 took at least one dose of treatment. Telcagepant was not statistically different from placebo for 2-hour pain freedom (25.0% vs 18.9%, odds ratio = 1.62 [95% confidence interval: 0.62, 4.25]). The median number of attacks treated per period was 3. No cardiovascular thrombotic adverse events occurred within 14 days of dosing. CONCLUSION: The study was underpowered due to enrollment difficulties and did not demonstrate a significant efficacy difference between telcagepant and placebo for the treatment of a migraine attack in patients with stable coronary artery disease. Telcagepant was generally well tolerated for acute intermittent migraine treatment in these patients.


Asunto(s)
Azepinas/uso terapéutico , Antagonistas del Receptor Peptídico Relacionado con el Gen de la Calcitonina , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Imidazoles/uso terapéutico , Trastornos Migrañosos/tratamiento farmacológico , Adulto , Anciano , Enfermedad de la Arteria Coronaria/complicaciones , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Femenino , Estudios de Seguimiento , Humanos , Cooperación Internacional , Masculino , Persona de Mediana Edad , Trastornos Migrañosos/complicaciones , Modelos Estadísticos , Índice de Severidad de la Enfermedad , Adulto Joven
6.
J Rheumatol ; 49(4): 380-387, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34853089

RESUMEN

OBJECTIVE: To evaluate the long-term efficacy and safety of ustekinumab through 2 years in patients with active systemic lupus erythematosus (SLE). METHODS: This was a placebo-controlled (week 24), phase II study in 102 patients with seropositive active SLE. Patients were randomized to ustekinumab (approximately 6 mg/kg single intravenous infusion, then subcutaneous [SC] injections of 90 mg every 8 weeks) or placebo, added to background therapy. Placebo patients initiated ustekinumab (90 mg SC every 8 weeks) at week 24. Patients could enter an optional open-label study extension after week 40 (final ustekinumab administration at week 104). Efficacy assessments included Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K), SLEDAI-2K Responder Index-4 (SRI-4), physician global assessment (PGA), and Cutaneous Lupus Erythematosus Disease Area and Severity Index (CLASI). Observed data are reported for the extension period. The final efficacy assessment was at week 112; safety was monitored through week 120. RESULTS: In this subset of patients who entered the study extension, 24 in the ustekinumab group and 14 in the placebo crossover group completed study treatment. At week 112, 79% and 92%, respectively, had an SRI-4 response; 92% in both groups had ≥ 4-point improvement from baseline in SLEDAI-2K score; 79% and 93%, respectively, had ≥ 30% improvement from baseline in PGA; 86% and 91%, respectively, had ≥ 50% improvement in active joint (pain and inflammation) count; and 79% and 100%, respectively, had ≥ 50% improvement in CLASI Activity Score. No deaths, malignancies, opportunistic infections, or tuberculosis cases occurred. Safety events were consistent with the known ustekinumab safety profile. CONCLUSION: Of the 46 patients who entered the voluntary extension of this phase II study, clinical benefit in global and organ-specific SLE activity measures was observed with ustekinumab through 2 years with no new or unexpected safety findings. [ClinicalTrials.gov: NCT02349061].


Asunto(s)
Lupus Eritematoso Sistémico , Ustekinumab , Método Doble Ciego , Humanos , Inyecciones Subcutáneas , Lupus Eritematoso Sistémico/tratamiento farmacológico , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Ustekinumab/efectos adversos
7.
Arthritis Rheumatol ; 72(5): 761-768, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31769212

RESUMEN

OBJECTIVE: To evaluate the efficacy and safety of ustekinumab through 1 year in a phase II trial in patients with systemic lupus erythematosus (SLE). METHODS: Eligible patients were diagnosed as having clinically active SLE (based on Systemic Lupus International Collaborating Clinics criteria), despite standard background therapy. Active disease was defined by an SLE Disease Activity Index 2000 (SLEDAI-2K) score of ≥6 as well as having ≥1 British Isles Lupus Assessment Group (BILAG) A organ domain score and/or ≥2 BILAG B organ domain scores present at screening. Patients (n = 102) were randomized (3:2) to receive either ustekinumab (~6 mg/kg of single intravenous infusion at week 0, then 90-mg subcutaneous injections every 8 weeks beginning at week 8) or a matching placebo added to standard therapy. At week 24, the placebo group crossed over to receive a subcutaneous 90-mg dose of ustekinumab every 8 weeks, and the original ustekinumab group continued to receive therapy through week 40. Maintenance of efficacy was assessed using the SLEDAI-2K, the SLE Responder Index 4 (SRI-4), physician global assessment, and mucocutaneous and joint disease measures in a modified intent-to-treat population. RESULTS: SRI-4 response rates were significantly greater in the ustekinumab group (62%) versus the placebo group (33%) in the week 24 primary end point analysis (P = 0.006) and were maintained at week 48 (63.3%) in the ustekinumab group. In the ustekinumab group, response rates across other disease measures were also maintained through week 48. Among patients in the placebo group who crossed over to ustekinumab treatment (n = 33), increased response rates across efficacy measures were noted. Among all ustekinumab-treated patients, 81.7% had ≥1 adverse event (AE), and 15.1% had ≥1 serious AE through week 56. No deaths, malignancies, opportunistic infections, or tuberculosis cases were observed. CONCLUSION: Ustekinumab provided sustained clinical benefit in patients with SLE through 1 year, with a safety profile consistent with other indications.


Asunto(s)
Lupus Eritematoso Sistémico/tratamiento farmacológico , Ustekinumab/uso terapéutico , Adulto , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Masculino , Estudios Prospectivos , Factores de Tiempo , Resultado del Tratamiento , Ustekinumab/efectos adversos
8.
RMD Open ; 4(2): e000731, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30564449

RESUMEN

OBJECTIVES: The phase III, multicentre, randomised, double-blind, placebo-controlled, parallel-group SIRROUND-D study evaluated long-term efficacy and safety of the interleukin (IL)-6 inhibitor, sirukumab, in patients with active rheumatoid arthritis (RA) refractory to disease-modifying antirheumatic drugs (DMARDs). METHODS: Patients were randomised 1:1:1 to sirukumab 100 mg every 2 weeks (q2w), 50 mg every 4 weeks or placebo q2w subcutaneously. Patients initially randomised to placebo were rerandomised at Weeks 18, 40 or 52 to one of the sirukumab groups until Week 104. RESULTS: Of 1670 randomised patients, 1402 were included in the full analysis set and 1269 in the radiographic analysis set at Week 104. American College of Rheumatology scores, Disease Activity Score based on C-reactive protein, Clinical Disease Activity Index and clinically meaningful improvements in patient-reported outcomes were sustained at Week 104 among patients initially randomised to sirukumab. Placebo patients subsequently rerandomised to sirukumab showed clinical improvements at Week 104 that were comparable to results among patients initially randomised to sirukumab. Radiographic progression from Week 52 to Week 104 was comparable between all groups whether initially randomised to sirukumab or subsequently rerandomised to sirukumab from placebo. No new safety signals were identified in the extended exposure period compared with the initial 52 weeks of treatment. CONCLUSIONS: Sirukumab treatment resulted in sustained reductions in clinical signs and symptoms and minimal progression in radiographic damage over 2 years among patients with RA refractory to DMARDs. The safety profile of sirukumab was as expected for an anti-IL-6 agent, with no new signals reported.

9.
Int J Rheum Dis ; 19(11): 1143-1156, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26259617

RESUMEN

AIM: The efficacy and safety of golimumab + methotrexate (MTX) were evaluated in Chinese patients with active rheumatoid arthritis (RA) despite MTX therapy. METHODS: Chinese patients (n = 264) were randomly assigned (1 : 1) to receive subcutaneous injections of placebo + MTX with crossover to golimumab 50 mg + MTX at week 24 (Group 1) or to golimumab 50 mg + MTX (Group 2) every 4 weeks. Group 1 patients with inadequate response entered blinded early escape to golimumab 50 mg + MTX at week 16. At least a 20% improvement in the American College of Rheumatology (ACR20) criteria at week 14 was the primary endpoint. Other assessments included the 28-joint count Disease Activity Score using C-reactive protein (DAS28-CRP) and Health Assessment Questionnaire-Disability Index (HAQ-DI) through week 52. Adverse events (AEs) were monitored through week 56. RESULTS: ACR20 response at week 14 was significantly higher in Group 2 (40.9% [54/132]) compared with Group 1 (15.9% [21/132]; P < 0.001). Greater proportions of patients in Group 2 compared with Group 1 had a DAS28-CRP response at week 14 (65.2% vs. 30.3%, P < 0.001) or ACR20 response at week 24 (42.4% vs. 15.9%, P < 0.001), and Group 2 had a significantly greater change in HAQ-DI at week 24 (-0.26 vs. 0.15, P < 0.001). After week 24, the proportion of patients achieving ACR20 in Group 1 approached that in Group 2. Through week 16, 23.5% of Group 1 and 26.7% of Group 2 patients reported AEs. Among golimumab + MTX-treated patients, 50.2% and 4.2% had ≥ 1 AE or serious AE, respectively, through week 56. No unexpected safety signals were observed. CONCLUSION: Among MTX-experienced Chinese patients with active RA, a significantly greater proportion of patients receiving golimumab + MTX had improvements in the signs and symptoms of RA compared with MTX monotherapy. Safety findings were consistent with previous studies of golimumab in patients with RA.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Metotrexato/uso terapéutico , Adulto , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/efectos adversos , Antirreumáticos/administración & dosificación , Antirreumáticos/efectos adversos , Artritis Reumatoide/diagnóstico , Artritis Reumatoide/inmunología , China , Método Doble Ciego , Quimioterapia Combinada , Femenino , Humanos , Inyecciones Subcutáneas , Masculino , Metotrexato/efectos adversos , Persona de Mediana Edad , Calidad de Vida , Inducción de Remisión , Factores de Tiempo , Insuficiencia del Tratamiento , Resultado del Tratamiento
10.
Int J Rheum Dis ; 19(11): 1083-1092, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27457311

RESUMEN

AIM: To conduct a subgroup analysis of GO-MORE trial Part 1, comparing efficacy and safety of add-on subcutaneous golimumab therapy in rheumatoid arthritis (RA) patients enrolled from and outside India. METHODS: GO-MORE was an open-label, multicenter, prospective trial of add-on golimumab in biologic-naïve RA patients, having active disease despite being on conventional DMARD regimen(s). Part 1 of the study was chosen as the focus of this subgroup analysis because a substantial number of Indian patients (106) were enrolled compared to no Indian patients in Part 2. The primary efficacy outcome was proportion of patients achieving good to moderate DAS28-ESR (Disease Activity Score of 28 joints calculated using erythrocyte sedimentation rate) European League Against Rheumatism (EULAR) response at month 6. RESULTS: Efficacy evaluable population comprised of 105 and 3175 patients from India and outside India, respectively. Safety analysis included 106 patients enrolled from India and 3251 from outside India. A higher proportion of Indian patients had a high disease activity as measured by DAS28 ESR than outside India patients. At month 6, the proportion of Indian and non-Indian patients achieving DAS28-ESR, DAS28 - C-reactive protein, simplified disease activity index (SDAI) remission, and EuroQoL Quality-of-Life Questionnaire (EQ-5D) scores were comparable. Incidence of all adverse events was lower in Indian patients. There were no deaths, cases of tuberculosis or malignancy reported in the patients from India at month 6. CONCLUSIONS: The efficacy and safety results with add-on golimumab were consistent between RA patients from India and outside India, despite high baseline disease activity in the Indian patients.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Adulto , Anciano , Anticuerpos Monoclonales/efectos adversos , Antirreumáticos/efectos adversos , Artritis Reumatoide/sangre , Artritis Reumatoide/diagnóstico , Biomarcadores/sangre , Sedimentación Sanguínea , Proteína C-Reactiva/metabolismo , Quimioterapia Combinada , Femenino , Humanos , India , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Calidad de Vida , Inducción de Remisión , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios , Factores de Tiempo , Resultado del Tratamiento
11.
Development ; 129(6): 1521-32, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11880360

RESUMEN

As a member of the phylum Cnidaria, the body wall of hydra is organized as an epithelium bilayer (ectoderm and endoderm) with an intervening extracellular matrix (ECM). Previous studies have established the general molecular structure of hydra ECM and indicate that it is organized as two subepithelial zones that contain basement membrane components such as laminin and a central fibrous zone that contains interstitial matrix components such as a unique type I fibrillar collagen. Because of its simple structure and high regenerative capacity, hydra has been used as a developmental model to study cell-ECM interaction during epithelial morphogenesis. The current study extends previous studies by focusing on the relationship of ECM biogenesis to epithelial morphogenesis in hydra, as monitored during head regeneration or after simple incision of the epithelium. Histological studies indicated that decapitation or incision of the body column resulted in an immediate retraction of the ECM at the wound site followed by a re-fusion of the bilayer within 1 hour. After changes in the morphology of epithelial cells at the regenerating pole, initiation of de novo biogenesis of an ECM began within hours while full reformation of the mature matrix required approximately 2 days. These processes were monitored using probes to three matrix or matrix-associated components: basement membrane-associated hydra laminin beta1 chain (HLM-beta1), interstitial matrix-associated hydra fibrillar collagen (Hcol-I) and hydra matrix metalloproteinase (HMMP). While upregulation of mRNA for both HLM-beta1 and Hcol-I occurred by 3 hours, expression of the former was restricted to the endoderm and expression of the latter was restricted to the ectoderm. Upregulation of HMMP mRNA was also associated with the endoderm and its expression paralleled that for HLM-beta1. As monitored by immunofluorescence, HLM-beta1 protein first appeared in each of the two subepithelial zones (basal lamina) at about 7 hours, while Hcol-I protein was first observed in the central fibrous zone (interstitial matrix) between 15 and 24 hours. The same temporal and spatial expression pattern for these matrix and matrix-associated components was observed during incision of the body column, thus indicating that these processes are a common feature of the epithelium in hydra. The correlation of loss of the ECM, cell shape changes and subsequent de novo biogenesis of matrix and matrix-associated components were all functionally coupled by antisense experiments in which translation of HLM-beta1 and HMMP was blocked and head regeneration was reversibly inhibited. In addition, inhibition of translation of HLM-beta1 caused an inhibition in the appearance of Hcol-I into the ECM, thus suggesting that binding of HLM-beta1 to the basal plasma membrane of ectodermal cells signaled the subsequent discharge of Hcol-I from this cell layer into the newly forming matrix. Given the early divergence of hydra, these studies point to the fundamental importance of cell-ECM interactions during epithelial morphogenesis.


Asunto(s)
Tipificación del Cuerpo/genética , Cnidarios/embriología , Colágeno/genética , Epitelio/embriología , Laminina/genética , Metaloproteinasas de la Matriz/genética , Animales , Cnidarios/genética , Colágeno/biosíntesis , Epitelio/fisiología , Regulación del Desarrollo de la Expresión Génica , Laminina/biosíntesis , Metaloproteinasas de la Matriz/biosíntesis
12.
Dev Genes Evol ; 212(4): 159-72, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12012231

RESUMEN

As a major component of the extracellular matrix (ECM), laminin has been found in many vertebrate and invertebrate organisms. Its molecular structure is very similar across species lines and its biological function in the ECM has been extensively studied. In an effort to study ECM structure and function in hydra, we have cloned a partial hydra laminin alpha chain and the full-length hydra laminin beta chain using ECM-enriched cDNA libraries. Analysis of deduced amino acid sequences indicated that both polypeptides have high sequence similarity to a number of invertebrate and vertebrate laminin alpha and beta subunits. Rotary shadow analysis of isolated hydra laminin indicates it has a heterotrimeric organization that is characteristic of vertebrate laminins. A putative integrin-class protein was also identified using a cell-binding peptide sequence from the laminin beta chain as an affinity probe, indicating that integrins are possible cell surface receptors in hydra. In agreement with previous results for the hydra laminin beta chain, in situ hybridization experiments revealed that hydra laminin alpha chain mRNA is restricted to endodermal cells. As with a number of other hydra ECM components, higher levels of laminin alpha chain mRNA are localized to regions where cell migration and differentiation are actively undertaken such as the base of tentacles, the peduncle region, buds, regenerating tentacles, and at the head end during regeneration. The role of laminin in morphogenesis was studied using an antisense approach and the results indicated that translation of the laminin alpha chain is required for head regeneration.


Asunto(s)
Laminina/fisiología , Secuencia de Aminoácidos , Animales , Cromatografía de Afinidad , Secuencia Conservada , Electroporación , Epitelio/embriología , Hydra , Laminina/química , Laminina/genética , Datos de Secuencia Molecular , Morfogénesis , Oligonucleótidos Antisentido , Especificidad de Órganos , Filogenia , Estructura Terciaria de Proteína , Relación Estructura-Actividad
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