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1.
Immunol Rev ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39285523

RESUMEN

The prevalence of asthma, rhinitis, and food allergies has increased dramatically over the last few decades. This increase originally started in western countries, but is now also evident in many other regions of the world. Given the fact that the increase is so quick, the noted increase cannot be linked to a genetic effect, and many environmental factors have been identified that are associated with increased or reduced prevalence of allergies, like changing dietary habits, increased urbanization, pollution, exposure to microorganisms and LPS, and the farming environment and raw milk consumption. Although the key role of allergen-specific IgE in allergies is well known, the role of allergen-specific IgG and IgA antibodies is less well defined. This review will provide an overview of the functions of allergen-specific IgE in allergy, the role of allergen-specific antibodies (IgG (4) and IgA) in allergen immunotherapy (AIT), the possibility to use allergen-specific antibodies for treatment of ongoing allergies, and the potential role of allergen-specific antibodies in tolerance induction to allergens in a preventive setting. In the last, more speculative, section we will present novel hypotheses on the potential role of allergen-specific non-IgE antibodies in allergies by directing antigen presentation, Th2 development, and innate immune training.

2.
Front Bioeng Biotechnol ; 12: 1440150, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39108599

RESUMEN

Interleukin-6 (IL-6) is a cytokine that can bind to IL-6 receptor and induce pleiotropic effects. It serves as a critical biomarker, involved in inflammation amplification, tumor progression, and many other disease developments. Nanobodies, featuring small structure and high affinity, are a powerful and versatile tool in medical diagnostics and therapeutics. Here, based on a scaffold optimized for humanization and stability, we developed a synthetic phage display library that rapidly generated high-affinity and humanized nanobodies, negating the need for animal immunization. Using enhanced green fluorescent protein (eGFP) as a benchmark, we demonstrated that the library produced humanized nanobodies with high function and great intracellular stability. The library was then subjected to screening against IL-6. We identified a standout nanobody, NbL3, which exhibited high affinity (22.16 nM) and stability and significantly inhibited IL-6-enhanced migration on the human breast cancer cell MCF-7 at a relatively low concentration. NbL3's strong blocking activity provides a promising therapeutic alternative for the IL-6-targeted intervention strategy, underscoring the broader potential of our synthetic library as a versatile platform for the development of humanized nanobodies against multiple antigens.

3.
Int J Cancer ; 154(7): 1285-1297, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38180065

RESUMEN

CD25, also known as the interleukin-2 receptor α chain (IL-2Rα), is highly expressed on regulatory T cells (Tregs), but relatively lower on effector T cells (Teffs). This makes it a potential target for Treg depletion, which can be used in tumor immunotherapy. However, marketed anti-CD25 antibodies (Basiliximab and Daclizumab) were originally developed as immunosuppressive drugs to prevent graft rejection, because these antibodies can block IL-2 binding to CD25 on Teffs, which in turn destroys the function of Teffs. Recent studies have shown that non-IL-2-blocking anti-CD25 antibodies have displayed exciting antitumor effects. Here, we screened out a non-IL-2-blocking anti-CD25 monoclonal antibody (mAb) 7B7 by hybridoma technology, and confirmed its antitumor activity via depleting Tregs in a CD25 humanized mouse model. Subsequently, we verified that the humanized 7B7, named as h7B7-15S, has comparable activities to 7B7, and that its Treg depletion is further increased when combined with anti-CTLA-4, leading to enhanced remodeling of the tumor immune microenvironment. Moreover, our findings reveal that the Fab form of h7B7-15S has the ability to deplete Tregs, independent of the Fc region. Taken together, our studies expand the application of anti-CD25 in tumor immunotherapy and provide insight into the underlying mechanism.


Asunto(s)
Anticuerpos Monoclonales , Neoplasias , Ratones , Animales , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Inmunosupresores , Linfocitos T Reguladores , Microambiente Tumoral
4.
J Control Release ; 366: 52-64, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38154541

RESUMEN

The poor penetration of monoclonal antibodies (mAb) across the blood-brain barrier (BBB) impedes the development of regenerative therapies for neurological diseases. For example, Nogo-A is a myelin-associated protein highly expressed in the central nervous system (CNS) whose inhibitory effects on neuronal plasticity can be neutralized with direct administration of 11C7 mAb in CNS tissues/fluids, but not with peripheral administrations such as intravenous injections. Therefore, in the present study, we engineered a CNS-penetrating antibody against Nogo-A by combining 11C7 mAb and the single-chain variable fragment (scFv) of 8D3, a rat antibody binding transferrin receptor 1 (TfR) and mediating BBB transcytosis (11C7-scFv8D3). The binding of 11C7-scFv8D3 to Nogo-A and to TfR/CD71 was validated by capture ELISA and Biolayer Interferometry. After intravenous injection in mice, capture ELISA measurements revealed fast plasma clearance of 11C7-scFv8D3 concomitantly with brain and spinal cord accumulation at levels up to 19 fold as high as those of original 11C7 mAb. 11C7-scFv8D3 detection in the parenchyma indicated effective blood-to-CNS transfer. A single dose of 11C7-scFv8D3 induced stronger activation of the growth-promoting AkT/mTOR/S6 signaling pathway than 11C7 mAb or control antibody. Taken together, our results show that BBB-crossing 11C7-scFv8D3 engages Nogo-A in the mouse CNS and stimulates neuronal growth mechanisms.


Asunto(s)
Anticuerpos Monoclonales , Barrera Hematoencefálica , Ratas , Ratones , Animales , Barrera Hematoencefálica/metabolismo , Proteínas Nogo , Anticuerpos Monoclonales/metabolismo , Encéfalo/metabolismo , Proteínas de la Mielina/metabolismo
5.
J Infect Dis ; 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37781879

RESUMEN

A GII.2 outbreak in an efficacy study of a bivalent virus-like particle (VLP) norovirus vaccine, TAK-214, in healthy US adults provided an opportunity to examine GII.4 homotypic vs. GII.2 heterotypic responses to vaccination and infection. Three serological assays (VLP-binding, histoblood group antigen-blocking, and neutralizing) were performed for each genotype. Results were highly correlated within a genotype but not between genotypes. Although the vaccine provided protection from GII.2-associated disease, little GII.2-specific neutralization occurred after vaccination. Choice of antibody assay can affect assessments of human norovirus vaccine immunogenicity.

6.
Cancer Cell Int ; 23(1): 204, 2023 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-37716943

RESUMEN

BACKGROUND: Triple negative breast cancer (TNBC) represents a significant clinical challenge. Chemotherapy remains the mainstay for a large part of TNBC patients, whereas drug resistance and tumor recurrence frequently occur. It is in urgent need to identify novel molecular targets for TNBC and develop effective therapy against the aggressive disease. METHODS: Immunohistochemistry was performed to examine the expression of HER3 in TNBC samples. Western blots were used to assess protein expression and activation. Cell proliferation and viability were determined by cell growth (MTS) assays. TCGA databases were analyzed to correlate HER3 mRNA expression with the clinical outcomes of TNBC patients. Specific shRNA was used to knockdown HER3 expression. IncuCyte system was utilized to monitor cell growth and migration. LIVE/DEAD Cell Imaging was to detect live and dead cells. HER3 recognition by our anti-HER3 monoclonal antibody (mAb) 4A7 was verified by ELISA, flow cytometry, and co-immunoprecipitation assays. Orthotopic tumor models were established in nude mice to determine the capability of TNBC cells forming tumors and to test if our mAb 4A7 could potentiate the antitumor activity of paclitaxel in vivo. RESULTS: Elevated expression of HER3 was observed in approximately half of the TNBC specimens and cell lines tested. Analyses of TCGA databases found that the TNBC patients with high HER3 mRNA expression in the tumors showed significantly worse overall survival (OS) and relapse-free survival (RFS) than those with low HER3 expression. Specific knockdown of HER3 markedly inhibited TNBC cell proliferation and mammosphere formation in vitro and tumor growth in vivo. Our mAb 4A7 abrogated heregulin (a ligand for HER3), but not SDF-1 (a ligand for CXCR4)-induced enhancement of TNBC cell migration. Combinations of 4A7 and the EGFR-tyrosine kinase inhibitor (TKI) gefitinib dramatically decreased the levels of phosphorylated HER3, EGFR, Akt, and ERK1/2 in TNBC cells and potently induced growth inhibition and cell death. Moreover, 4A7 in combination with paclitaxel exerted significant antitumor activity against TNBC in vitro and in vivo. CONCLUSIONS: Our data demonstrate that increased HER3 is an effective therapeutic target for TNBC and our anti-HER3 mAb (4A7) may enhance the efficacy of gefitinib or paclitaxel in TNBC.

7.
Cureus ; 15(8): e43823, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37736453

RESUMEN

Primary hypothyroidism is a known risk factor for pituitary hyperplasia, which develops symptoms due to compression of the optic chiasma and increased intracranial pressure. As pituitary hyperplasia is known to improve after levothyroxine replacement therapy, there are no reports of a long clinical course of pituitary hyperplasia due to primary hypothyroidism. We describe a case of follow-up over 16 years for pathologically diagnosed pituitary hyperplasia due to primary hypothyroidism with positive thyroid stimulation blocking antibody. Repeated enlargement and shrinkage were confirmed, but observations also suggested that the pituitary gland did not always return to normal size.

8.
bioRxiv ; 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37461695

RESUMEN

Most cases of gastric cancer are caused by chronic Helicobacter pylori infection, but the lack of early onco-diagnostics and a high risk for antibiotic resistance hampers early intervention through eradication of H. pylori infection by antibiotics. We reported on a protective mechanism where H. pylori gastric mucosal attachment can be reduced by natural antibodies that block the binding of its attachment protein BabA. Here we show that challenge infection with H. pylori induced response of such blocking antibodies in both human volunteers and in rhesus macaques, that mucosal vaccination with BabA protein antigen induced blocking antibodies in rhesus macaques, and that vaccination in a mouse model induced blocking antibodies that reduced gastric mucosal inflammation, preserved the gastric juice acidity, and fully protected the mice from gastric cancer caused by H. pylori.

9.
bioRxiv ; 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37292721

RESUMEN

The majority of the world population carry the gastric pathogen Helicobacter pylori. Fortunately, most individuals experience only low-grade or no symptoms, but in many cases the chronic inflammatory infection develops into severe gastric disease, including duodenal ulcer disease and gastric cancer. Here we report on a protective mechanism where H. pylori attachment and accompanying chronic mucosal inflammation can be reduced by antibodies that are present in a vast majority of H. pylori carriers. These antibodies block binding of the H. pylori attachment protein BabA by mimicking BabA's binding to the ABO blood group glycans in the gastric mucosa. However, many individuals demonstrate low titers of BabA blocking antibodies, which is associated with an increased risk for duodenal ulceration, suggesting a role for these antibodies in preventing gastric disease.

10.
Hematol Oncol ; 41 Suppl 1: 57-61, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37294968

RESUMEN

The treatment of Hodgkin lymphoma, using cytotoxic chemotherapy and selective radiotherapy, has resulted in progressively increasing cure rates over the last 40 years. Recent studies have been directed at using response-adapted approaches to modulate treatment according to the responses seen using functional imaging, with the aim of balancing the probability of cure against the toxicity of more extensive treatments, in particular the risks of infertility, second malignancy and cardiovascular disease. The results of these studies suggest that we have reached the limits of what might be expected from the conventional treatments, but the arrival of antibody-based therapies, specifically antibody-drug conjugates and immune checkpoint blocking antibodies, now holds out the prospect of further improvements. The next challenge will be to select those groups for whom they are most needed.


Asunto(s)
Enfermedad de Hodgkin , Inmunoconjugados , Humanos , Enfermedad de Hodgkin/tratamiento farmacológico , Resinas Compuestas/uso terapéutico , Inmunoconjugados/uso terapéutico
11.
Antibodies (Basel) ; 12(2)2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-37092449

RESUMEN

Neuritin represents a neurotrophic factor that is not only important in neuronal development and plasticity but also impacts endothelial angiogenesis, cell migration, tumor growth and the production of antibodies by B cells. We established monoclonal mouse anti-mouse neuritin antibodies by immunizing knock-out mice with two different neuritin-derived peptides. Because neuritin is well conserved between species, these new monoclonal antibodies recognize the neuritin of a wide variety of species, including human. Moreover, they not only recognize specifically surface-bound neuritin expressed by murine follicular regulatory T cells but also the block binding of recombinant neuritin to germinal center B cells. This suggests that these newly generated tools will be of great use in studying neuritin expression and function.

12.
Curr Oncol Rep ; 25(6): 647-657, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37004702

RESUMEN

PURPOSE OF REVIEW: Dual immune checkpoint inhibition with ipilimumab plus nivolumab is currently the most effective, but also by far the most toxic treatment for advanced melanoma. Therefore, other combination partners that also lead to high and long-lasting responses but cause fewer adverse events were explored. RECENT FINDINGS: Relatlimab, a LAG-3 blocking antibody, was investigated in combination with nivolumab in a phase 2/3 randomized double-blind trial (RELATIVITY-047) and could demonstrate significantly improved progression-free survival in treatment-naive advanced melanoma patients compared with nivolumab monotherapy. While the safety profile is more favorable than that of ipilimumab plus nivolumab, no significant survival benefit has yet been demonstrated with the new combination over nivolumab monotherapy. The approval of relatlimab plus nivolumab by both the Food and Drug Administration and the European Medicines Agency expands the arsenal of treatment options for melanoma but raises new questions in clinical practice and a re-evaluation of currently established treatment standards and sequences.


Asunto(s)
Melanoma , Nivolumab , Humanos , Nivolumab/uso terapéutico , Nivolumab/efectos adversos , Ipilimumab/uso terapéutico , Ipilimumab/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Melanoma/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto
13.
Acta Biochim Biophys Sin (Shanghai) ; 54(10): 1518-1527, 2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36239354

RESUMEN

CD70 is overexpressed in a variety of solid and hematological tumors and plays a role in tumor proliferation and evasion of immune surveillance. Targeting and blocking its binding to the receptor CD27 have the potential to treat CD70-dependent tumors. To generate novel CD70 blocking agents, we screen a human CD70-immunized camel VHH phage display library and isolate two blocking nanobodies against human CD70 targeting different epitopes. Upon enrichment by three rounds of biopanning, two strategies are employed to identify CD70 blockers. One named affinity selection is used for detecting clones with CD70 binding by conventional PE-ELISA. However, no clone with a blocking effect is obtained from 188 enriched clones by this method. The alternative strategy named competitive selection is based on the inhibiting capacity of CD70-CD27 binding by enriched VHHs. By this method, two clones, Nb-2B3 and Nb-3B6, with strong blocking capacity are obtained from 20 enriched VHHs, suggesting the efficiency of this strategy. Furthermore, Nb-2B3 and Nb-3B6 specifically bind to CD70-positive SKOV3 and Raji cells at low concentrations. Meanwhile, Nb-2B3 has no competitive effect on the binding of Nb-3B6 to CD70, and vice versa, indicating that they target two different epitopes on CD70. Our data show that nanobodies Nb-2B3 and Nb-3B6 are potential attractive theranostic agents for CD70-expressing cancers.


Asunto(s)
Neoplasias , Anticuerpos de Dominio Único , Humanos , Anticuerpos de Dominio Único/farmacología , Epítopos , Biblioteca de Genes , Ensayo de Inmunoadsorción Enzimática , Ligando CD27
14.
Cancer Genet ; 268-269: 103-110, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36288641

RESUMEN

PD-1/PD-L1 pathway caused immunosuppression accounts, at least partly, for the poor therapeutic effect of Chimeric Antigen Receptor T (CAR-T) on solid tumors. In this study, we designed and prepared CAR-T cells that could secrete PD-L1 blocking antibody and target Mesothelin antigen (Sec-MesoCAR-T), to remove the immunosuppressive effect of tumor on CAR-T cells, thereby increasing the therapeutic effect of CAR-T cells on pancreatic cancer. The CAR-T cells that could not secret PD-L1 blocking antibodies (MesoCAR-T) were used as a control. Sec-MesoCAR-T cells showed an enhanced inhibitory effect on BxPC-3 tumor than MesoCAR-T cells in vitro and in vivo. Besides, Sec-MesoCAR-T cells secreted higher level of cytokines including IL-2, IL-6 and IFN-γ in vitro than MesoCAR-T cells. Following injection, there were significantly more CAR-T cells in the peripheral blood of Sec-MesoCAR-T group than that of MesoCAR-T group. This work demonstrated that the PD-L1 antibody secreted by Sec-MesoCAR-T cells relieved the immunosuppressive effect of pancreatic cancer on CAR-T cells and improved the anti-tumor activity of CAR-T cells, which has a good guiding significance for the clinical application of CAR-T cells in treating solid tumors.


Asunto(s)
Antígeno B7-H1 , Neoplasias Pancreáticas , Humanos , Antígeno B7-H1/metabolismo , Mesotelina , Línea Celular Tumoral , Linfocitos T , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas
15.
Monoclon Antib Immunodiagn Immunother ; 41(5): 231-242, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35852870

RESUMEN

Next-generation allergy vaccines refer to allergen-derived attenuated molecules that can boost allergen-blocking IgG response. These IgG antibodies are specifically directed toward the IgE epitope of allergens and interfere in allergen-IgE interaction. Our study is a computational approach to design such vaccines against four widespread pan-allergens families. Pan-allergens display extensive immunological cross-reactivity due to the presence of conserved IgE epitope and T cell epitope. In this study, the vaccine design is based on hapten-carrier concept in which the carrier protein is an immunogenic component providing T cell help. Either PreS protein of hepatitis B or cholera enterotoxin B (CTB) fused with three tetanus toxoid fragments (TTFrC) was used here as the carrier. The hapten components are nonanaphylactic peptides (NAPs) derived from experimentally determined antigenic regions of the allergens. The charged residues of NAPs are selectively modified to obliterate IgE, as well as T cell reaction, and hence, are safe to apply in allergy patients. Various combinations of vaccine constructs (PreS/CTB+TTFrC and NAPs) were designed with intermediate linker motifs. Screening of constructs was performed through a three-step method such as physicochemical parameters, secondary structures, and tertiary structures using various bioinformatic tools. The final construct with best quality and stability was selected for each allergen family. Suitability of these constructs for being expressed in recombinant form was checked at DNA, RNA, and protein level. Presence of putative epitopes inducing tolerogenic interleukin-10 was also predicted for these constructs. The present work led to the design of putative vaccines with immunotherapeutic potential and broad applicability for allergic diseases caused by a wide array of cross-reactive allergens.


Asunto(s)
Hipersensibilidad , Vacunas , Humanos , Alérgenos/genética , Alérgenos/química , Anticuerpos Monoclonales , Epítopos de Linfocito T/genética , Epítopos de Linfocito T/química , Haptenos , Inmunoglobulina E/metabolismo , Inmunoglobulina G , Péptidos
16.
Proc Natl Acad Sci U S A ; 119(30): e2119048119, 2022 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-35858411

RESUMEN

The major challenges in pancreatic ductal adenocarcinoma (PDAC) management are local or distant metastasis and limited targeted therapeutics to prevent it. To identify a druggable target in tumor secretome and to explore its therapeutic intervention, we performed a liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomic analysis of tumors obtained from a patient-derived xenograft model of PDAC. Galectin-3 binding protein (Gal-3BP) is identified as a highly secreted protein, and its overexpression is further validated in multiple PDAC tumors and primary cells. Knockdown and exogenous treatment of Gal-3BP showed that it is required for PDAC cell proliferation, migration, and invasion. Mechanistically, we revealed that Gal-3BP enhances galectin-3-mediated epidermal growth factor receptor signaling, leading to increased cMyc and epithelial-mesenchymal transition. To explore the clinical impact of these findings, two antibody clones were developed, and they profoundly abrogated the metastasis of PDAC cells in vivo. Altogether, our data demonstrate that Gal-3BP is an important therapeutic target in PDAC, and we propose its blockade by antibody as a therapeutic option for suppressing PDAC metastasis.


Asunto(s)
Antígenos de Neoplasias , Antineoplásicos Inmunológicos , Biomarcadores de Tumor , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animales , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/inmunología , Antineoplásicos Inmunológicos/inmunología , Antineoplásicos Inmunológicos/uso terapéutico , Biomarcadores de Tumor/antagonistas & inhibidores , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/inmunología , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/secundario , Carcinoma Ductal Pancreático/terapia , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Cromatografía Liquida , Transición Epitelial-Mesenquimal , Técnicas de Silenciamiento del Gen , Humanos , Ratones , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/terapia , Proteómica , Secretoma , Espectrometría de Masas en Tándem , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Cells ; 11(11)2022 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-35681481

RESUMEN

Activating and inhibitory immune receptors play a critical role in regulating systemic and central nervous system (CNS) immune and inflammatory processes. The CD200R1 immunoreceptor induces a restraining signal modulating inflammation and phagocytosis in the CNS under different inflammatory conditions. However, it remains unknown whether CD200R1 has a role in modulating the inflammatory response after a peripheral nerve injury, an essential component of the successful regeneration. Expression of CD200R1 and its ligand CD200 was analyzed during homeostasis and after a sciatic nerve crush injury in C57Bl/6 mice. The role of CD200R1 in Wallerian Degeneration (WD) and nerve regeneration was studied using a specific antibody against CD200R1 injected into the nerve at the time of injury. We found an upregulation of CD200R1 mRNA after injury whereas CD200 was downregulated acutely after nerve injury. Blockade of CD200R1 significantly reduced the acute entrance of both neutrophils and monocytes from blood after nerve injury. When long term regeneration and functional recovery were evaluated, we found that blockade of CD200R1 had a significant effect impairing the spontaneous functional recovery. Taken together, these results show that CD200R1 has a role in mounting a successful acute inflammatory reaction after injury, and contributes to an effective functional recovery.


Asunto(s)
Regeneración Nerviosa , Receptores de Orexina , Traumatismos de los Nervios Periféricos , Animales , Ratones , Compresión Nerviosa , Receptores de Orexina/metabolismo , Fagocitosis/genética , Nervio Ciático
18.
Cancer Immunol Immunother ; 71(11): 2777-2789, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35437609

RESUMEN

Cancer immunotherapy, which blocks immune checkpoint molecules, is an effective therapeutic strategy for human cancer patients through restoration of tumor-infiltrating (TI) cell function. However, evaluating the efficacy of immune checkpoint inhibitors (ICIs) is difficult because no standard in vitro assay for ICI efficacy evaluation exists. Additionally, blocking a particular immune checkpoint receptor (ICR) is insufficient to restore T cell functionality, because other ICRs still transduce inhibitory signals. Therefore, limiting inhibitory signals transduced via other ICRs is needed to more accurately assess the efficacy of ICIs targeting a particular immune checkpoint. Here, we introduce a newly developed in vitro coculture assay using human peripheral blood mononuclear cells (hPBMCs) and engineered human cancer cell lines. We enriched CD8+ T cells from hPBMCs of healthy donors through low-dose T cell receptor stimulation and cytokine (human IL-2 and IL-7) addition. These enriched CD8+ T cells were functional and expressed multiple ICRs, especially TIM-3 and TIGIT. We also established immune checkpoint ligand (ICL) knockout (KO) cancer cell lines with the CRISPR-Cas9 system. Then, we optimized the in vitro coculture assay conditions to evaluate ICI efficacy. For example, we selected the most effective anti-TIM-3 antibody through coculture of TIM-3+CD8+ T cells with PD-L1-/-PVR-/- cancer cells. In summary, we developed a mechanism-based in vitro coculture assay with hPBMCs and ICL KO cancer cell lines, which could be a useful tool to identify promising ICIs by providing reliable ICI efficacy information.


Asunto(s)
Antígeno B7-H1 , Neoplasias , Linfocitos T CD8-positivos , Técnicas de Cocultivo , Humanos , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Proteínas de Punto de Control Inmunitario , Interleucina-2 , Interleucina-7 , Leucocitos Mononucleares , Ligandos , Neoplasias/tratamiento farmacológico , Receptores Inmunológicos
19.
Mol Ther Oncolytics ; 24: 719-728, 2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35317521

RESUMEN

Although chimeric antigen receptor (CAR) T cell immunotherapy has shown promising significance in B cell malignancies, success against T cell malignancies remains unsatisfactory because of shared antigenicity between normal and malignant T cells, resulting in fratricide and hindering CAR production for clinical treatment. Here, we report a new strategy of blocking the CD7 antigen on the T cell surface with a recombinant anti-CD7 antibody to obtain a sufficient amount of CD7-targeting CAR-T cells for T cell acute lymphoblastic leukemia (T-ALL) treatment. Feasibility was evaluated systematically, revealing that blocking the CD7 antigen with an antibody effectively blocked CD7-derived fratricide, increased the expansion rate, reduced the proportion of regulatory T (Treg) cells, maintained the stem cell-like characteristics of T cells, and restored the proportion of the CD8+ T cell population. Ultimately, we obtained anti-CD7 CAR-T cells that were specifically and effectively able to kill CD7 antigen-positive target cells, obviating the need for complex T cell modifications. This approach is safer than previous methods and provides a new, simple, and feasible strategy for clinical immunotherapies targeting CD7-positive malignant tumors.

20.
Elife ; 112022 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-35344481

RESUMEN

Antibodies targeting the protein that causes placental malaria can recognise multiple variants of the protein, which may help guide the development of new vaccines to protect pregnant women from malaria.


Asunto(s)
Malaria Falciparum , Malaria , Complicaciones Parasitarias del Embarazo , Anticuerpos Antiprotozoarios , Femenino , Humanos , Malaria/prevención & control , Placenta , Embarazo
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