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1.
bioRxiv ; 2024 Aug 27.
Article in English | MEDLINE | ID: mdl-39253415

ABSTRACT

Acute myeloid leukemia (AML) is a malignancy of immature myeloid blast cells with stem-like and chemoresistant cells being retained in the bone marrow through CXCL12-CXCR4 signaling. Current CXCR4 inhibitors mobilize AML cells into the bloodstream where they become more chemosensitive have failed to improve patient survival, likely reflecting persistent receptor localization on target cells. Here we characterize the signaling properties of CXCL12-locked dimer (CXCL12-LD), a bioengineered variant of the dimeric CXCL12 structure. CXCL12-LD binding resulted in lower levels of G protein, ß-arrestin, and intracellular calcium mobilization, consistent with the locked dimer being a partial agonist of CXCR4. Further, CXCL12-LD failed to induce chemotaxis in AML cells. Despite these partial agonist properties, CXCL12-LD increased CXCR4 internalization compared to wildtype and locked-monomer forms of CXCL12. Analysis of a previously published AML transcriptomic data showed CXCR4 positive AML cells co-express genes involved in chemoresistance and maintenance of a blast-like state. The CXCL12-LD partial agonist effectively mobilized stem cells into the bloodstream in mice suggesting a potential role for their use in targeting CXCR4. Together, our results suggest that enhanced internalization by CXCL12-LD partial agonist signaling can avoid pharmacodynamic tolerance and may identify new avenues to better target GPCRs.

2.
Psychoanal Rev ; 111(3): 253-276, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39325521

ABSTRACT

This article revisits W. R. Bion's theory of thinking by highlighting how thinking and linking are attacked. The author's theoretical reflections and clinical vignettes draw attention to the fact that patients may attack the analyst's thinking-function in two particular states: when they experience the analyst as attacking them precisely when the analyst is able to create a link, but one that is too threatening, painful, unsettling and frustrating or in response to the analyst's failure to create the link the patient had been expecting. How the analyst deals with and reacts to the complexity of the analytic relationship and to these two kinds of attacks is what will be internalized. In turn, it will affect the methods of communication within the psyche and with the environment and the development of a patient's emotional thinking.


Subject(s)
Psychoanalytic Theory , Psychoanalytic Therapy , Thinking , Humans , Psychoanalytic Therapy/methods , Professional-Patient Relations , Countertransference
3.
J Control Release ; 375: 478-494, 2024 Sep 20.
Article in English | MEDLINE | ID: mdl-39293528

ABSTRACT

Nanoparticles fabricated to deliver anticancer drugs are usually designed to present optimized tumor penetration and cell internalization. However, there are some barriers and difficulties with most current technologies. Herein, size and charge switchable polyamidoamine (PAMAM) megamers (SChPMs) were prepared for the delivery of doxorubicin (DOX). SChPMs were fabricated by connecting PAMAM dendrimers with pH-sensitive bonds and surface PEGylation. At pH 7.4, the size and surface charge of these nanocarriers were approximately 100 nm and + 0.75 mV, but at the acidic extracellular pH of tumor cells (pH 6.5), their size were reduced dramatically (15 nm) and their surface charge increased to +6.7 mV. Cell studies confirmed that alteration of the size and surface charge enhanced their penetration into multicellular spheroids and cell internalization. These megamers, in addition to delivering the drug to the deeper areas of the tumor, could powerfully overcome physiological resistance to anthracycline-based drugs. The nanocarrier revealed enhanced antitumoral activity in animal studies. Toxicology studies and histopathological assessments of vital tissues of 4 T1 tumor bearing mice indicated minimal tissue damage when DOX-loaded SChPMs (DSChPMs) were used. It can be concluded that the versatile and agile nanocarriers developed in this study could be considered for further investigations into their clinical application.

4.
mBio ; : e0156124, 2024 Sep 26.
Article in English | MEDLINE | ID: mdl-39324816

ABSTRACT

Host-microbe interactions that facilitate entry into mammalian cells are essential for obligate intracellular bacterial survival and pathogenesis. Anaplasma phagocytophilum is an obligate intracellular bacterium that invades neutrophils to cause granulocytic anaplasmosis. The invasin-receptor pairs and signaling events that induce Anaplasma uptake are inadequately defined. A. phagocytophilum invasion protein A orchestrates entry via residues 9-21 (AipA9-21) engaging an unknown receptor. Yeast two-hybrid screening suggested that AipA binds within C-terminal amino acids 851-967 of CD13 (aminopeptidase N), a multifunctional protein that, when crosslinked, initiates Src kinase and Syk signaling that culminates in endocytosis. Co-immunoprecipitation validated the interaction and confirmed that it requires the AipA N-terminus. CD13 ectopic expression on non-phagocytic cells increased susceptibility to A. phagocytophilum infection. Antibody blocking and enzymatic inhibition experiments found that the microbe exploits CD13 but not its ectopeptidase activity to infect myeloid cells. A. phagocytophilum induces Src and Syk phosphorylation during invasion. Inhibitor treatment established that Src is key for A. phagocytophilum infection, while Syk is dispensable and oriented the pathogen-invoked signaling pathway by showing that Src is activated before Syk. Disrupting the AipA-CD13 interaction with AipA9-21 or CD13781-967 antibody inhibited Src and Syk phosphorylation and also infection. CD13 crosslinking antibody that induces Src and Syk signaling restored infectivity of anti-AipA9-21-treated A. phagocytophilum. The bacterium poorly infected CD13 knockout mice, providing the first demonstration that CD13 is important for microbial infection in vivo. Overall, A. phagocytophilum AipA9-21 binds CD13 to induce Src signaling that mediates uptake into host cells, and CD13 is critical for infection in vivo. IMPORTANCE: Diverse microbes engage CD13 to infect host cells. Yet invasin-CD13 interactions, the signaling they invoke for pathogen entry, and the relevance of CD13 to infection in vivo are underexplored. Dissecting these concepts would advance fundamental understanding of a convergently evolved infection strategy and could have translational benefits. Anaplasma phagocytophilum infects neutrophils to cause granulocytic anaplasmosis, an emerging disease for which there is no vaccine and few therapeutic options. We found that A. phagocytophilum uses its surface protein and recently identified protective immunogen, AipA, to bind CD13 to elicit Src kinase signaling, which is critical for infection. We elucidated the AipA CD13 binding domain, which CD13 region AipA engages, and established that CD13 is key for A. phagocytophilum infection in vivo. Disrupting the AipA-CD13 interaction could be utilized to prevent granulocytic anaplasmosis and offers a model that could be applied to protect against multiple infectious diseases.

5.
Br J Pharmacol ; 2024 Sep 18.
Article in English | MEDLINE | ID: mdl-39294930

ABSTRACT

BACKGROUND AND PURPOSE: The pattern recognition receptors, formyl peptide receptors, FPR1 and FPR2, are G protein-coupled receptors that recognize many different pathogen- and host-derived ligands. While FPR1 conveys pro-inflammatory signals, FPR2 is linked with pro-resolving outcomes. To analyse how the two very similar FPRs exert opposite effects in modulating inflammatory responses despite their high homology, a shared expression profile on immune cells and an overlapping ligand repertoire, we questioned whether the signalling profile differs between these two receptors. EXPERIMENTAL APPROACH: We deduced EC50 and Emax values for synthetic, pathogen-derived and host-derived peptide agonists for both FPR1 and FPR2 and analysed them within the framework of biased signalling. We furthermore investigated whether FPR isoform-specific agonists affect the ex vivo lifespan of human neutrophils. KEY RESULTS: The FPRs share a core signature across signalling pathways. Whereas the synthetic WKYMVm and formylated peptides acted as potent agonists at FPR1, and at FPR2, only WKYMVm was a full agonist. Natural FPR2 agonists, irrespective of N-terminal formylation, displayed lower activity ratios, suggesting an underutilized signalling potential of this receptor. FPR2 agonism did not counteract LPS-induced neutrophil survival, indicating that FPR2 activation per se is not linked with a pro-resolving function. CONCLUSION AND IMPLICATIONS: Activation of FPR1 and FPR2 by a representative agonist panel revealed a lack of a receptor-specific signalling texture, challenging assumptions about distinct inflammatory profiles linked to specific receptor isoforms, signalling patterns or agonist classes. These conclusions are restricted to the specific agonists and signalling pathways examined.

6.
J Res Health Sci ; 24(3): e00620, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-39311103

ABSTRACT

BACKGROUND: Weight bias internalization (WBI) is a serious challenge because of its negative impact on psychological consequences. Although the cognitive-behavioral intervention has been applied to reduce WBI, little is known about its effectiveness among Thai obese youth. Thus, this study sought to determine the effects of a cognitive-behavioral group counseling (CBGC) program on WBI and psychological outcomes in obese youths. Study Design: A randomized controlled trial. METHODS: Eighty obese youths were randomly allocated to two intervention (n=40) and control (n=40) groups. The intervention group received a CBGC program in three sessions with ten activities, while the control group performed their usual counseling process. Data were collected through standardized interviewers with a structured interview questionnaire. The chi-square test, independent samples t-test, Mann-Whitney U test, repeated measure ANOVA, and multivariate linear regression were applied for data analyses. RESULTS: At the follow-up visit, the intervention group had a significant decrease in the mean of WBI, depression, and perceived stress and an increased mean of self-esteem compared to the control group. After adjusting baseline characteristics and baseline outcome values, the intervention also significantly improved WBI (B=-6.82, P<0.001), depression (B=-4.17, P<0.001), perceived stress (B=-6.01, P<0.001), and self-esteem (B=5.07, P<0.001). CONCLUSION: The CBGC program effectively reduced WBI, depression, and perceived stress while improving self-esteem among obese youths. This study recommends that group counseling programs be employed as part of a counseling process for obese youth who have experienced WBI.


Subject(s)
Cognitive Behavioral Therapy , Counseling , Obesity , Humans , Female , Male , Thailand , Cognitive Behavioral Therapy/methods , Adolescent , Counseling/methods , Obesity/psychology , Obesity/therapy , Self Concept , Depression/psychology , Depression/therapy , Universities , Stress, Psychological/therapy , Stress, Psychological/psychology , Psychotherapy, Group/methods , Body Image/psychology , Surveys and Questionnaires , Body Weight , Treatment Outcome
7.
Front Immunol ; 15: 1406643, 2024.
Article in English | MEDLINE | ID: mdl-39263220

ABSTRACT

Introduction: Immunogenicity, the unwanted immune response triggered by therapeutic antibodies, poses significant challenges in biotherapeutic development. This response can lead to the production of anti-drug antibodies, potentially compromising the efficacy and safety of treatments. The internalization of therapeutic antibodies into dendritic cells (DCs) is a critical factor influencing immunogenicity. Using monoclonal antibodies, with differences in non-specific cellular uptake, as tools to explore the impact on the overall risk of immunogenicity, this study explores how internalization influences peptide presentation and subsequently T cell activation. Materials and methods: To investigate the impact of antibody internalization on immunogenicity, untargeted toolantibodies with engineered positive or negative charge patches were utilized. Immature monocyte-derived DCs (moDCs), known for their physiologically relevant high endocytic activity, were employed for internalization assays, while mature moDCs were used for MHC-II associated peptide proteomics (MAPPs) assays. In addition to the lysosomal accumulation and peptide presentation, subsequent CD4+ T cell activation has been assessed. Consequently, a known CD4+ T cell epitope from ovalbumin was inserted into the tool antibodies to evaluate T cell activation on a single, shared epitope. Results: Antibodies with positive charge patches exhibited higher rates of lysosomal accumulation and epitope presentation compared to those with negative charge patches or neutral surface charge. Furthermore, a direct correlation between internalization rate and presentation on MHC-II molecules could be established. To explore the link between internalization, peptide presentation and CD4+ T cell activation, tool antibodies containing the same OVA epitope were used. Previous observations were not altered by the insertion of the OVA epitope and ultimately, an enhanced CD4+ T cell response correlated with increased internalization in DCs and peptide presentation. Discussion: These findings demonstrate that the biophysical properties of therapeutic antibodies, particularly surface charge, play a crucial role in their internalization into DCs. Antibodies internalized faster and processed by DCs, are also more prone to be presented on their surface leading to a higher risk of triggering an immune response. These insights underscore the importance of considering antibody surface charge and other properties that enhance cellular accumulation during the preclinical development of biotherapeutics to mitigate immunogenicity risks.


Subject(s)
Antigen Presentation , Dendritic Cells , Lymphocyte Activation , Dendritic Cells/immunology , Dendritic Cells/metabolism , Humans , Antigen Presentation/immunology , Lymphocyte Activation/immunology , Antibodies, Monoclonal/immunology , CD4-Positive T-Lymphocytes/immunology , Epitopes, T-Lymphocyte/immunology , Risk Factors , Endocytosis/immunology , Ovalbumin/immunology
8.
APMIS ; 2024 Sep 02.
Article in English | MEDLINE | ID: mdl-39223818

ABSTRACT

BamA, an Omp85 superfamily member, is universally conserved and essential for cell viability. Using anti-Oma87 antibodies, we focus on understanding the effect of Oma87 of Acinetobacter baumannii on pathogenicity. Oma87 was expressed, purified, and used to induce anti-Oma87 antibodies in BALB/c mice. Acute toxicity of the protein was evaluated in mice. HeLa cells were infected with both live and killed A. baumannii 19606 and a clinical isolate. The effects of anti-Oma87 sera on A. baumannii adherence, internalization, and proliferation in HeLa cells were studied. The roles of microfilaments and microtubules in A. baumannii invasion were demonstrated by Actin disruption. Reduced bacterial population and biofilm formation were noted. The ability of A. baumannii to provoke autophagy through Oma87 induction leads to incomplete autophagy and potentially facilitates bacterial replication. Actin-mediated uptake, attachment, and invasion demonstrated A. baumannii survival and multiplication within vacuoles in the host cell. The findings underscore the potential of Oma87 as a therapeutic intervention target in infections caused by A. baumannii. This comprehensive analysis contributes valuable information for understanding the virulence mechanisms of A. baumannii, potentially guiding future strategies to combat infections caused by this pathogen.

9.
Biomed Khim ; 70(4): 240-247, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39239898

ABSTRACT

Extracellular vesicles (EVs), exhibiting their functional activity after internalization by recipient cells, are involved in the pathogenesis of drug-induced polyneuropathy (DIPN), a common complication of antitumor therapy. In this work, the internalization of EVs obtained from colorectal cancer patients undergoing polychemotherapy and its relationship with neurotoxicity were assessed using a model system of mononuclear leukocytes. Circulating EVs were isolated from 8 colorectal cancer patients who received antitumor therapy according to the FOLFOX or XELOX regimens before the start of chemotherapy (point 1) and after 3-4 courses (point 2). Mononuclear leukocytes of a healthy donor served as a cellular model system for EV internalization in vitro. EV internalization was assessed using fluorescence microscopy. It was shown that internalization of EVs obtained from colorectal cancer patients with high neurotoxicity was higher than in the group with low neurotoxicity. The ability of CD11b-positive (CD11b⁺) and CD11b-negative (CD11b⁻) mononuclear leukocytes of a healthy donor to internalize EVs obtained from patients before and after chemotherapy did not reveal significant differences. A direct relationship was found between the relative number of CD11b⁻ cells with internalized EVs and the integral index of neurotoxicity according to the NRS scale at the peak of its manifestation (point 2) (r=0.675, p.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols , Extracellular Vesicles , Leukocytes, Mononuclear , Humans , Leukocytes, Mononuclear/metabolism , Leukocytes, Mononuclear/drug effects , Extracellular Vesicles/metabolism , Extracellular Vesicles/drug effects , Male , Female , Middle Aged , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/pathology , Colorectal Neoplasms/metabolism , Fluorouracil/adverse effects , Fluorouracil/pharmacology , Capecitabine/adverse effects , Capecitabine/pharmacology , CD11b Antigen/metabolism , Organoplatinum Compounds/adverse effects , Organoplatinum Compounds/pharmacology , Leucovorin/pharmacology , Oxaloacetates , Adult , Polyneuropathies/chemically induced , Polyneuropathies/metabolism , Polyneuropathies/pathology
10.
Bioorg Med Chem ; 112: 117883, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39180861

ABSTRACT

Tagging of cell permeable nuclear localization sequence (NLS) with receptor targeting peptide vectors is an attractive strategy for selectively targeted translocation of therapeutic cargoes. The present study aimed at grafting nuclear localization sequence (NLS) onto breast cancer targeting rL-A9 peptide. Molecular docking analysis revealed higher binding affinity of the peptide, DOTA-NLS-rL-A9 (-26.1 kJ/mol) towards HER2 receptor in comparison to DOTA-rL-A9 peptide (-22.2 kJ/mol). Confocal microscopy data suggested significantly enhanced cellular internalization of NLS-tagged peptide. The engineered HER2-selective, DOTA-NLS-rL-A9 peptide scaffold was radiolabeled with Lu-177 for intracellular delivery of the theranostic radionuclide into tumor cells. [177Lu]Lu-DOTA-NLS-rL-A9 exhibited significantly enhanced binding affinity (4.58 ± 1.77 nM) towards human breast carcinoma SKBR3 cells and cellular internalization (85 % at 24 h) compared to its original analog, [177Lu]Lu-DOTA-rL-A9. In vivo biodistribution studies showed consistent retention of [177Lu]Lu-DOTA-NLS-rL-A9 in the tumor with negligible washout of radioactivity (∼4.1 % ID/g at 48 h). Prolonged tumor activity with rapid off-target tissue clearance resulted in significantly high tumor-to-background ratios. The radiopeptide, [177Lu]Lu-DOTA-NLS-rL-A9 thus, being precisely confined into HER2-expressing tumor cells and exhibiting favourable pharmacokinetic features is an efficient candidate for further screening.


Subject(s)
Lutetium , Nuclear Localization Signals , Radioisotopes , Receptor, ErbB-2 , Humans , Lutetium/chemistry , Receptor, ErbB-2/metabolism , Animals , Nuclear Localization Signals/chemistry , Radioisotopes/chemistry , Mice , Female , Peptides/chemistry , Peptides/chemical synthesis , Cell Line, Tumor , Breast Neoplasms/pathology , Molecular Docking Simulation , Radiopharmaceuticals/chemistry , Radiopharmaceuticals/chemical synthesis , Radiopharmaceuticals/pharmacology , Tissue Distribution
11.
Cell Rep ; 43(9): 114685, 2024 Aug 29.
Article in English | MEDLINE | ID: mdl-39213151

ABSTRACT

Signaling through classical death receptor Fas was mainly appreciated as a pro-death pathway until recent reports characterized pro-inflammatory outcomes of Fas-mediated activation in pathological contexts. How Fas signaling can switch to pro-inflammatory activation is poorly understood. Herein, we report that in macrophages and neutrophils, the Toll-like receptor (TLR) adapter CD14 determines the inflammatory output of Fas-mediated signaling. Our findings propose CD14 as a crucial chaperone of Fas receptor internalization in macrophages and neutrophils, resulting in Cd14-/- myeloid cells that are protected from FasL-induced apoptosis, activate nuclear factor κB (NF-κB), and release cytokines in response. As in TLR signaling, CD14 is also required for Fas to signal through the adaptor TRIF (TIR-domain-containing adapter-inducing interferon-ß) and induce a pro-death complex. Our findings demonstrate that CD14 availability can determine the switch between Fas-mediated pro-death and pro-inflammatory outcomes by internalizing the receptor.

12.
ACS Biomater Sci Eng ; 10(9): 5689-5700, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39167686

ABSTRACT

Drug delivery advances rely on using nano- and microsized carriers to transfer therapeutic molecules, although challenges persist in increasing the availability of new and even approved pharmaceutical products. Particle shape, a critical determinant in how these carriers distribute within the body after administration, raises opportunities of using, for instance, micrometer-sized nonspherical particles for vascular targeting and thereby creating new prospects for precise drug delivery to specific targeted areas. The versatility of polycrystalline silicon microfabrication allows for significant variation in the size and shape of microchips, and so, in the current work, photolithography was employed to create differently shaped polysilicon microchips, including cuboids, cubes, bars, and cylinders, to explore the influence of particle shape on cellular interactions. These microchips with different shapes and lateral dimensions, accounting for surface areas in the range of ca. 15 to 120 µm2 and corresponding total volumes of 0.4 to 27 µm3, serve as ideal models for investigating their interactions with macrophages with diameters of ca. 20 µm. Side-scattering imaging flow cytometry was employed for studying the interaction of label-free prepared microchips with RAW 264.7 macrophages. Using a dose of 3 microchips per cell, results show that cuboids exhibit the highest cellular association (ca. 25%) and uptake (ca. 20%), suggesting their potential as efficient carriers for targeted drug delivery to macrophages. Conversely, similarly sized cylinders and bar-shaped microchips exhibit lower uptakes of about 8% and about 6%, respectively, indicating potential benefits in evading macrophage recognition. On average, 1-1.5 microchips were internalized, and ca. 1 microchip was surface-bound per cell, with cuboids showing the higher values overall. Macrophages respond to microchips by increasing their metabolic activity and releasing low levels of intracellular enzymes, indicating reduced toxicity. Interestingly, increasing the particle dose enhances macrophage metabolic activity without significantly affecting enzyme release.


Subject(s)
Macrophages , Macrophages/metabolism , Animals , Mice , RAW 264.7 Cells , Particle Size , Lab-On-A-Chip Devices
13.
Exp Eye Res ; 247: 110062, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39187056

ABSTRACT

Exposure to VEGF-A165a over several days leads to a persistent dysfunction of the very tight barrier formed by immortalized endothelial cells of the bovine retina (iBREC). Elevated permeability of the barrier is indicated by low cell index values determined by electric cell-substrate impedance measurements, by lower amounts of claudin-1, and by disruption of the homogenous and continuous staining of vascular endothelial cadherin at the plasma membrane. Because of findings that suggest modulation of VEGF-A's detrimental effects on the inner blood-retina barrier by the angiogenic growth factor angiopoietin-2, we investigated in more detail in vitro whether this growth factor indeed changes the stability of the barrier formed by retinal endothelial cells or modulates effects of VEGF-A. In view of the clinical relevance of anti-VEGF therapy, we also studied whether blocking VEGF-A-driven signaling is sufficient to prevent barrier dysfunction induced by a combination of both growth factors. Although angiopoietin-2 stimulated proliferation of iBREC, the formed barrier was not weakened at a concentration of 3 nM: Cell index values remained high and expression or subcellular localization of claudin-1 and vascular endothelial cadherin, respectively, were not affected. Angiopoietin-2 enhanced the changes induced by VEGF-A165a and this was more pronounced at lower concentrations of VEGF-A165a. Specific inhibition of the VEGF receptors with tivozanib as well as interfering with binding of VEGF-A to its receptors with bevacizumab prevented the detrimental effects of the growth factors; dual binding of angiopoietin-2 and VEGF-A by faricimab was marginally more efficient. Uptake of extracellular angiopoietin-2 by iBREC can be efficiently prevented by addition of faricimab which is also internalized by the cells. Exposure of the cells to faricimab over several days stabilized their barrier, confirming that inhibition of VEGF-A signaling is not harmful to this cell type. Taken together, our results confirm the dominant role of VEGF-A165a in processes resulting in increased permeability of retinal endothelial cells in which angiopoietin-2 might play a minor modulating role.


Subject(s)
Angiopoietin-2 , Blood-Retinal Barrier , Cadherins , Cell Proliferation , Vascular Endothelial Growth Factor A , Animals , Cattle , Angiogenesis Inhibitors/pharmacology , Angiopoietin-2/metabolism , Antigens, CD/metabolism , Cadherins/metabolism , Capillary Permeability/drug effects , Capillary Permeability/physiology , Cell Proliferation/drug effects , Cells, Cultured , Claudin-1/metabolism , Electric Impedance , Endothelial Cells/metabolism , Endothelial Cells/drug effects , Endothelium, Vascular/metabolism , Endothelium, Vascular/drug effects , Endothelium, Vascular/cytology , Peptide Fragments , Retinal Vessels/cytology , Retinal Vessels/metabolism , Tight Junctions/metabolism , Vascular Endothelial Growth Factor A/metabolism
14.
Bioessays ; 46(10): e2400144, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39180250

ABSTRACT

R-spondins (RSPOs) are a family of secreted proteins and stem cell growth factors that are potent co-activators of Wnt signaling. Recently, RSPO2 and RSPO3 were shown to be multifunctional, not only amplifying Wnt- but also binding BMP- and FGF receptors to downregulate signaling. The common mechanism underlying these diverse functions is that RSPO2 and RSPO3 act as "endocytosers" that link transmembrane proteins to ZNRF3/RNF43 E3 ligases and trigger target internalization. Thus, RSPOs are natural protein targeting chimeras for cell surface proteins. Conducting data mining and cell surface binding assays we report additional candidate RSPO targets, including SMO, PTC1,2, LGI1, ROBO4, and PTPR(F/S). We propose that there is an "R-spondin code" that imparts combinatorial signaling ON-OFF states of multiple growth factors. This code involves the modular RSPO domains, notably distinct motifs in the divergent RSPO-TSP1 domains to mediate target interaction and internalization. The RSPO code offers a novel framework for the understanding how diverse signaling pathways may be coordinately regulated in development and disease.


Subject(s)
Thrombospondins , Thrombospondins/metabolism , Thrombospondins/genetics , Humans , Animals , Signal Transduction , Ubiquitin-Protein Ligases/metabolism , Ubiquitin-Protein Ligases/genetics , Wnt Signaling Pathway , Intercellular Signaling Peptides and Proteins
15.
Front Immunol ; 15: 1373498, 2024.
Article in English | MEDLINE | ID: mdl-39192975

ABSTRACT

Introduction: Visceral leishmaniasis (VL) is an important tropical and neglected disease and represents a serious global health problem. The initial interaction between the phagocytes and the parasite is crucial to determine the pathogen's capacity to initiate infection and it shapes the subsequent immune response that will develop. While type-1 T-cells induce IL-6, IL-1ß, TNF-α, and IL-12 production by monocytes/macrophages to fight the infection, type-2 T-cells are associated with a regulatory phenotype (IL-10 and TGF-ß) and successful infection establishment. Recently, our group demonstrated the role of an important Th1/Th17 T-cell population, the mucosal-associated invariant T (MAIT) cells, in VL. MAIT cells can respond to L. infantum by producing TNF-α and IFN-γ upon MR1-dependent activation. Objective and methods: Here, we describe the impact of the MR1-blockage on L. infantum internalization on the functional profile of circulating neutrophils and monocytes as well as the impact of the MR1-blockage on the soluble mediator signatures of in vitro whole blood cultures. Results: Overall, our data showed that VL patients presents higher percentage of activated neutrophils than asymptomatic and non-infected controls. In addition, MR1 blockade led to lower TNF-α and TGF-ß production by non-activated neutrophils from asymptomatic individuals. Moreover, TNF-α and IL-10 production by monocytes was higher in VL patients. In the analysis of soluble mediators produced in vitro, MR1-blockade induced a decrease of IFN-γ and an increase of IL-10, IL-27 and IL-33 in the cell cultures of AS group, a cytokine pattern associated with type 2 deleterious response. Discussion and conclusion: These data corroborate the hypothesis that MR1-restricted responses are associated to a protective role during Leishmania infection.


Subject(s)
Cytokines , Leishmaniasis, Visceral , Monocytes , Leishmaniasis, Visceral/immunology , Humans , Cytokines/metabolism , Adult , Female , Male , Monocytes/immunology , Monocytes/metabolism , Leishmania infantum/immunology , Neutrophils/immunology , Neutrophils/metabolism , Mucosal-Associated Invariant T Cells/immunology , Mucosal-Associated Invariant T Cells/metabolism , Middle Aged , Young Adult , Adolescent
16.
Bioorg Med Chem ; 111: 117867, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-39121678

ABSTRACT

Currently, antibody drugs targeting programmed cell death ligand 1 (PD-L1) have achieved promising results in cancer treatment, while the development of small-molecule drugs lags behind. In this study, we designed and synthesized a series of PD-L1-degrading agents based on the PROTAC design principle, utilizing the PD-L1 inhibitor A56. Through systematic screening of ligands and linkers and investigating the structure-activity relationship of the degraders, we identified two highly active compounds, 9i and 9j. These compounds enhance levels of CD4+, CD8+, granzyme B, and perforin, demonstrating significant in vivo antitumor effects with a tumor growth inhibition (TGI) of up to 57.35 %. Both compounds facilitate the internalization of PD-L1 from the cell surface and promote its degradation through proteasomal and lysosomal pathways, while also maintaining inhibition of the PD-1/PD-L1 interaction. In summary, our findings provide a novel strategy and mechanism for developing biphenyl-based PROTAC antitumor drugs targeting and degrading PD-L1.


Subject(s)
Antineoplastic Agents , B7-H1 Antigen , Cell Proliferation , Drug Design , Drug Screening Assays, Antitumor , Programmed Cell Death 1 Receptor , Humans , B7-H1 Antigen/metabolism , B7-H1 Antigen/antagonists & inhibitors , Structure-Activity Relationship , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Programmed Cell Death 1 Receptor/metabolism , Molecular Structure , Animals , Cell Proliferation/drug effects , Mice , Dose-Response Relationship, Drug , Cell Line, Tumor , Proteolysis Targeting Chimera
17.
Sci Rep ; 14(1): 19225, 2024 08 20.
Article in English | MEDLINE | ID: mdl-39160236

ABSTRACT

Glioblastoma (GBM), one of the deadliest brain tumors, accounts for approximately 50% of all primary malignant CNS tumors, therefore novel, highly effective remedies are urgently needed. Boron neutron capture therapy, which has recently repositioned as a promising strategy to treat high-grade gliomas, requires a conspicuous accumulation of boron atoms in the cancer cells. With the aim of selectively deliver sodium borocaptate (BSH, a 12 B atoms-including molecule already employed in the clinics) to GBM cells, we developed novel cell membrane-derived vesicles (CMVs), overcoming the limits of natural extracellular vesicles as drug carriers, while maintaining their inherent homing abilities that make them preferable to fully synthetic nanocarriers. Purified cell membrane fragments, isolated from patient-derived GBM stem-like cell cultures, were used to prepare nanosized CMVs, which retained some membrane proteins specific of the GBM parent cells and were devoid of potentially detrimental genetic material. In vitro tests evidenced the targeting ability of this novel nanosystem and ruled out any cytotoxicity. The CMVs were successfully loaded with BSH, by following two different procedures, i.e. sonication and electroporation, demonstrating their potential applicability in GBM therapy.


Subject(s)
Boron Neutron Capture Therapy , Brain Neoplasms , Cell Membrane , Glioblastoma , Humans , Boron Neutron Capture Therapy/methods , Glioblastoma/radiotherapy , Glioblastoma/pathology , Glioblastoma/therapy , Brain Neoplasms/radiotherapy , Brain Neoplasms/pathology , Cell Membrane/metabolism , Borohydrides/chemistry , Cell Line, Tumor , Drug Carriers/chemistry , Nanoparticles/chemistry , Sulfhydryl Compounds
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 323: 124888, 2024 Dec 15.
Article in English | MEDLINE | ID: mdl-39116589

ABSTRACT

An important issue in the context of both potenial toxicity of iron oxide nanoparticles (IONP) and their medical applications is tracking of the internalization process of these nanomaterials into living cells, as well as their localization and fate within them. The typical methods used for this purpose are transmission electron microscopy, confocal fluorescence microscopy as well as light-scattering techniques including dark-field microscopy and flow cytometry. All the techniques mentioned have their advantages and disadvantages. Among the problems it is necessary to mention complicated sample preparation, difficult interpretation of experimental data requiring qualified and experienced personnel, different behavior of fluorescently labeled IONP comparing to those label-free or finally the lack of possibility of chemical composition characteristics of nanomaterials. The purpose of the present investigation was the assessment of the usefulness of Raman microscopy for the tracking of the internalization of IONP into cells, as well as the optimization of this process. Moreover, the study focused on identification of the potential differences in the cellular fate of superparamagnetic nanoparticles having magnetite and maghemite core. The Raman spectra of U87MG cells which internalized IONP presented additional bands which position depended on the used laser wavelength. They occurred at the wavenumber range 1700-2400 cm-1 for laser 488 nm and below the wavenumber of 800 cm-1 in case of laser 532 nm. The intensity of the mentioned Raman bands was higher for the green laser (532 nm) and their position, was independent and not characteristic on the primary core material of IONP (magnetite, maghemite). The obtained results showed that Raman microscopy is an excellent, non-destructive and objective technique that allows monitoring the process of internalization of IONP into cells and visualizing such nanoparticles and/or their metabolism products within them at low exposure levels. What is more, the process of tracking IONP using the technique may be further improved by using appropriate wavelength and power of the laser source.


Subject(s)
Magnetic Iron Oxide Nanoparticles , Spectrum Analysis, Raman , Spectrum Analysis, Raman/methods , Humans , Magnetic Iron Oxide Nanoparticles/chemistry , Cell Line, Tumor , Microscopy/methods , Ferric Compounds/chemistry , Ferric Compounds/analysis , Ferric Compounds/metabolism
19.
Front Psychol ; 15: 1409980, 2024.
Article in English | MEDLINE | ID: mdl-39156816

ABSTRACT

Introduction: The boom of social media has provided a wider space for ordinary people to display themselves, but visual presentation has also intensified the focus on appearance, which in turn triggers anxiety about appearance. The study aims to investigate the impact of social media information exposure on appearance anxiety in young acne patients and the pathways and mechanisms that cause this effect. Methods: A moderated chain mediation model was constructed, and a questionnaire was used to collect information on social media information exposure, internalization of beauty ideals, fear of negative evaluation, self-esteem, and appearance anxiety in young acne patients (N = 382), and the relationships between the variables were explored through regression analysis. Results: The results show that there was a significant path of effect (t > 2.5, p < 0.05) between social media information exposure, internalization of beauty ideals, fear of negative evaluation, and appearance anxiety. Self-esteem significantly moderated the relationship between social media information exposure and internalization of beauty ideals (t < -2, p < 0.05). Discussion: In conclusion, in young acne patients, internalization of beauty ideals and fear of negative evaluation chain mediated the association between social media information exposure and appearance anxiety, and young acne patients' internalization of beauty ideals was inversely correlated with their level of self-esteem.

20.
Article in English | MEDLINE | ID: mdl-39177231

ABSTRACT

Exploiting the chirality of nanometric structures to modulate biological systems is an emerging and compelling area of research. In this study, we reveal that chiral polyurea nanocapsules exhibit significant stereoselective interactions with albumins from various sources despite their nearly neutral surface potential. Moreover, these interactions can be modulated by altering the nanocapsule surface composition, offering new opportunities to impact their distribution and, if used as a drug delivery system, the pharmacokinetics of the drug. Notably, these interactions promote preferential cellular internalization of only one chiral configuration. We synthesized chiral polyurea nanocapsules with reproducible sizes via interfacial polymerization between toluene 2,4-diisocyanate and d- or l-lysine enantiomers on a volatile oil-in-water emulsion interface, followed by solvent evaporation. Further synthesis optimization reduced the capsule size to a range compatible with in vivo administration, and capsules with alternating chiral patterns were also produced. The stereoselective interactions with albumins were assessed through capsule size changes, fluorescence quenching, and surface charge measurements. Biocompatibility, stability, and cellular internalization were evaluated. Additionally, scanning transmission electron and atomic force microscopy were carried out to assess the capsule shape, surface composition, and morphology. We discovered that d-nanocapsules exhibited 2.1-2.6 times greater albumin adsorption compared with their l-counterparts. This difference is attributed to the distinct morphology of d-nanocapsules, characterized by a more concave shape, central depression, and rougher surface. The extent of adsorption could be finely tuned by adjusting the d- and l-lysine monomer ratios during synthesis. Both chiral configurations demonstrated biocompatibility and stability with d-nanocapsules showing a 2.5-fold increase in cellular internalization.

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