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1.
World J Clin Cases ; 11(20): 4944-4955, 2023 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-37583995

RESUMO

BACKGROUND: Eosinophilic granuloma (EG) is a proliferative condition that affects the cells of bone tissue. There are no specific clinical signs or imaging manifestations in the early stages of the disease, making it simple to overlook and misdiagnose. Because of the disease's rarity, there is presently no standardized treatment principle. There are few accounts of such occurrences affecting the axis among children. We discovered a case of a child whose EG resulted in atlantoaxial joint dislocation and destruction of the axial bone. CASE SUMMARY: After having pharyngeal discomfort for more than six months without a clear explanation, a 6-year-old boy was brought to our hospital. Following a careful evaluation, the pathology indicated a strong likelihood of an axial EG. Ultimately, we decided to treat the boy with posterior pedicle screw fixation and local steroid injections. CONCLUSION: EGs of the upper cervical spine are quite uncommon in children, and they are exceedingly easy to overlook or misdiagnose. Posterior pedicle screw fixation and local steroid injections are effective treatments for patients with axial EGs affecting the atlantoaxial junction.

2.
Cytotherapy ; 24(7): 720-732, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35570170

RESUMO

BACKGROUND: Chimeric antigen receptor (CAR) T cell therapy has yielded impressive clinical results in hematological malignancies and is a promising approach for solid tumor treatment. However, toxicity, including cytokine-release syndrome (CRS) and neurotoxicity, is a concern hampering its broader use. METHODS: In selecting a lead CAR-T candidate against the oncofetal antigen glypican 3 (GPC3), we compared CARs bearing a low- and high-affinity single-chain variable fragment (scFv) binding to a similar epitope and cross-reactive with murine GPC3. RESULTS: Where the high-affinity CAR-T cells were toxic in vivo, the low-affinity CAR maintained cytotoxic function against antigen-positive tumor cells but did not show toxicity against normal tissues. High-affinity CAR-induced toxicity was caused by on-target, off-tumor binding, based on the observation that higher doses of the high-affinity CAR-T caused toxicity in non-tumor-bearing mice and accumulated in organs with low expression of GPC3. To explore another layer of controlling CAR-T toxicity, we developed a means to target and eliminate CAR-T cells using anti-TNF-α antibody therapy after CAR-T infusion. The antibody was shown to function by eliminating early antigen-activated, but not all, CAR-T cells, allowing a margin where the toxic response could be effectively decoupled from antitumor efficacy with only a minor loss in tumor control. By exploring additional traits of the CAR-T cells after activation, we identified a mechanism whereby we could use approved therapeutics and apply them as an exogenous kill switch that eliminated early activated CAR-T following antigen engagement in vivo. CONCLUSIONS: By combining the reduced-affinity CAR with this exogenous control mechanism, we provide evidence that we can modulate and control CAR-mediated toxicity.


Assuntos
Glipicanas , Receptores de Antígenos Quiméricos , Animais , Linhagem Celular Tumoral , Glipicanas/metabolismo , Imunoterapia Adotiva/métodos , Camundongos , Receptores de Antígenos de Linfócitos T , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T , Inibidores do Fator de Necrose Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
3.
J Orthop Surg Res ; 13(1): 43, 2018 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-29499742

RESUMO

BACKGROUND: Posterior short-segment pedicle screw fixation is used to treat thoracolumbar burst fractures. However, no randomized controlled studies have compared the efficacy of the two approaches--the Wiltse's paraspinal approach and open book laminectomy in the treatment of thoracolumbar burst fractures with greenstick lamina fractures. MATERIALS AND METHODS: Patients with burst fractures of the thoracolumbar spine without neurological deficit were randomized to receive either the Wiltse's paraspinal approach (group A, 24 patients) or open book laminectomy (group B, 23 patients). Patients were followed postoperatively for average of 27.4 months. Clinical and radiographic data of the two approaches were collected and compared. RESULTS: Our results showed the anterior segmental height, kyphotic angle, visual analog scale (VAS) score, and Smiley-Webster Scale (SWS) score significantly improved postoperatively in both groups, indicating that both the Wiltse's paraspinal approach and open book laminectomy can effectively treat thoracolumbar burst fractures with greenstick lamina fractures. The Wiltse's paraspinal approach was found to have significantly shorter operating time, less blood loss, and shorter length of hospital stay compared to open book laminectomy. However, there were two (2/24) patients in group A that had neurological deficits postoperatively and required a second exploratory operation. Dural tears and/or cauda equina entrapment were subsequently found in four patients in group B and all two patients of neurological deficits in group A during operation. No screw loosening, plate breakage, or other internal fixation failures were found at final follow-up. CONCLUSIONS: The results demonstrated that either of the two surgical approaches can achieve satisfactory results in treating thoracolumbar burst fractures in patients with greenstick lamina fractures. However, if there is any clinical or radiographic suspicion of a dural tear and/or cauda equina entrapment pre-operation, patients should receive an open book laminectomy to avoid a second exploratory operation. More research is still needed to optimize clinical decision-making regarding surgical approach.


Assuntos
Fixação Interna de Fraturas/métodos , Vértebras Lombares/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Vértebras Torácicas/cirurgia , Adolescente , Adulto , Perda Sanguínea Cirúrgica , Feminino , Seguimentos , Fixação Interna de Fraturas/efeitos adversos , Humanos , Laminectomia/efeitos adversos , Laminectomia/métodos , Tempo de Internação/estatística & dados numéricos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/lesões , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Parafusos Pediculares , Estudos Prospectivos , Radiografia , Fraturas da Coluna Vertebral/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/lesões , Tomografia Computadorizada por Raios X , Adulto Jovem
4.
MAbs ; 5(2): 208-18, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23575268

RESUMO

The recognition that few human diseases are thoroughly addressed by mono-specific, monoclonal antibodies (mAbs) continues to drive the development of antibody therapeutics with additional specificities and enhanced activity. Historically, efforts to engineer additional antigen recognition into molecules have relied predominantly on the reformatting of immunoglobulin domains. In this report we describe a series of fully functional mAbs to which additional specificities have been imparted through the recombinant fusion of relatively short polypeptides sequences. The sequences are selected for binding to a particular target from combinatorial libraries that express linear, disulfide-constrained, or domain-based structures. The potential for fusion of peptides to the N- and C- termini of both the heavy and light chains affords the bivalent expression of up to four different peptides. The resulting molecules, called zybodies, can gain up to four additional specificities, while retaining the original functionality and specificity of the scaffold antibody. We explore the use of two clinically significant oncology antibodies, trastuzumab and cetuximab, as zybody scaffolds and demonstrate functional enhancements in each case. The affect of fusion position on both peptide and scaffold function is explored, and penta-specific zybodies are demonstrated to simultaneously engage five targets (ErbB2, EGFR, IGF-1R, Ang2 and integrin αvß3). Bispecific, trastuzumab-based zybodies targeting ErbB2 and Ang2 are shown to exhibit superior efficacy to trastuzumab in an angiogenesis-dependent xenograft tumor model. A cetuximab-based bispecific zybody that targeting EGFR and ErbB3 simultaneously disrupted multiple intracellular signaling pathways; inhibited tumor cell proliferation; and showed efficacy superior to that of cetuximab in a xenograft tumor model.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Especificidade de Anticorpos , Neoplasias/terapia , Peptídeos/uso terapêutico , Proteínas Recombinantes de Fusão/uso terapêutico , Sequência de Aminoácidos , Angiopoietina-2/química , Angiopoietina-2/genética , Angiopoietina-2/imunologia , Animais , Anticorpos Biespecíficos/genética , Anticorpos Biespecíficos/imunologia , Anticorpos Biespecíficos/metabolismo , Anticorpos Biespecíficos/uso terapêutico , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Cetuximab , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Dados de Sequência Molecular , Neovascularização Patológica , Peptídeos/genética , Peptídeos/imunologia , Peptídeos/metabolismo , Engenharia de Proteínas/métodos , Receptor ErbB-2/química , Receptor ErbB-2/genética , Receptor ErbB-2/imunologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Transdução de Sinais , Trastuzumab , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
5.
MAbs ; 4(5): 600-13, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22864384

RESUMO

Despite the clinical success of anti-tumor necrosis factor (TNF) therapies in the treatment of inflammatory conditions such as rheumatoid arthritis, Crohn disease and psoriasis, full control of the diseases only occurs in a subset of patients and there is a need for new therapeutics with improved efficacy against broader patient populations. One possible approach is to combine biological therapeutics, but both the cost of the therapeutics and the potential for additional toxicities needs to be considered. In addition to the various mediators of immune and inflammatory pathways, angiogenesis is reported to contribute substantially to the overall pathogenesis of inflammatory diseases. The combination of an anti-angiogenic agent with anti-TNF into one molecule could be more efficacious without the risk of severe immunosuppression. To evaluate this approach with our Zybody technology, we generated bispecific antibodies that contain an Ang2 targeting peptide genetically fused to the anti-TNF antibody adalimumab (Humira®). The bispecific molecules retain the binding and functional characteristics of the anti-TNF antibody, but with additional activity that neutralizes Ang2. In a TNF transgenic mouse model of arthritis, the bispecific anti-TNF-Ang2 molecules showed a dose-dependent reduction in both clinical symptoms and histological scores that were significantly better than that achieved by adalimumab alone.


Assuntos
Angiopoietina-2/imunologia , Anticorpos Biespecíficos/uso terapêutico , Anticorpos Monoclonais Humanizados/imunologia , Proteínas Recombinantes de Fusão/uso terapêutico , Fator de Necrose Tumoral alfa/imunologia , Adalimumab , Angiopoietina-2/genética , Animais , Anticorpos Biespecíficos/imunologia , Anticorpos Monoclonais Humanizados/genética , Artrite Reumatoide/imunologia , Artrite Reumatoide/terapia , Linhagem Celular , Modelos Animais de Doenças , Humanos , Inflamação/terapia , Camundongos , Camundongos Transgênicos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Resultado do Tratamento
6.
Mol Cancer Ther ; 5(12): 3122-9, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17172415

RESUMO

The humanized monoclonal antibody Abegrin, currently in phase II trials for treatment of solid tumors, specifically recognizes the integrin alphavbeta3. Due to its high expression on mature osteoclasts, angiogenic endothelial cells, and tumor cells, integrin alphavbeta3 functions in several pathologic processes important to tumor growth and metastasis. Targeting of this integrin with Abegrin results in antitumor, antiangiogenic, and antiosteolytic activities. Here, we exploit the species specificity of Abegrin to evaluate the effects of direct targeting of tumor cells (independent of targeting of endothelia or osteoclasts). Flow cytometry analysis of human tumor cell lines shows high levels of alphavbeta3 on many solid tumors, including cancers of the prostate, skin, ovary, kidney, lung, and breast. We also show that tumor growth of alphavbeta3-expressing tumor cells is inhibited by Abegrin in a dose-dependent manner. We present a novel finding that high-dose administration can actively impair the antitumor activity of Abegrin. We also provide evidence that antibody-dependent cellular cytotoxicity contributes to in vitro and in vivo antitumor activity. Finally, it was observed that peak biological activity of Abegrin arises at serum levels that are consistent with those achieved in clinical trials. These results support a concept that Abegrin can be used to achieve selective targeting of the many tumor cells that express alphavbeta3 integrin. In combination with the well-established concept that alphavbeta3 plays a key role in cancer-associated angiogenesis and osteolytic activities, this triad of activity could provide new opportunities for therapeutic targeting of cancer.


Assuntos
Anticorpos Monoclonais/farmacologia , Integrina alfaVbeta3/imunologia , Neoplasias/terapia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais Humanizados , Citotoxicidade Celular Dependente de Anticorpos , Linhagem Celular Tumoral , Relação Dose-Resposta Imunológica , Feminino , Humanos , Integrina alfaVbeta3/biossíntese , Camundongos , Camundongos Nus , Camundongos SCID , Neoplasias/imunologia , Especificidade da Espécie , Ensaios Antitumorais Modelo de Xenoenxerto
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