Receptor Targeting Research Articles

Formulation and characterization of CMPI nanoparticles for enhanced targeting of brain nicotinic receptors by positive allosteric modulator

Formulation and characterization of CMPI nanoparticles for enhanced targeting of brain nicotinic receptors by positive allosteric modulator

Mechanisms of Peptide Agonist Dissociation and Deactivation of Adhesion G-Protein-Coupled Receptors.

Adhesion G protein-coupled receptors (ADGRs) belong to Class B2 of GPCRs and are involved in a wide array of important physiological processes. ADGRs contain a GPCR autoproteolysis-inducing domain that is proximal to the receptor N-terminus and undergoes autoproteolysis during the biosynthesis to generate two fragments: the N-terminal fragment (NTF) and the C-terminal fragment (CTF). Dissociation of NTF reveals a tethered agonist to activate the CTF of ADGRs for G protein signaling. Synthetic peptides that mimic the tethered agonist can also activate ADGRs. However, mechanisms of peptide agonist dissociation and the deactivation of ADGRs remain poorly understood. In this study, we have performed all-atom enhanced sampling simulations using a novel protein-protein interaction Gaussian-accelerated molecular dynamics (PPI-GaMD) method on the ADGRG2-IP15 and ADGRG1-P7 complexes. The PPI-GaMD simulations captured the dissociation of the IP15 and P7 peptide agonists from their target receptors. We were able to identify important low-energy conformations of ADGRG2 and ADGRG1 in the active, intermediate, and inactive states, as well as different states of the peptide agonists IP15 and P7 during dissociation. Therefore, our PPI-GaMD simulations have revealed dynamic mechanisms of peptide agonist dissociation and deactivation of ADGRG1 and ADGRG2, which will facilitate the rational design of peptide regulators of the two receptors and other ADGRs.

Effect of pH-Responsive Ligands on mRNA Knockdown in EGFR-Targeting Ligand-Conjugated siRNAs.

Ligand-conjugated small interfering RNAs (siRNAs) have emerged as a powerful approach to developing nucleic acid-based medicines. To achieve efficient mRNA knockdown, it is important to select targeting receptors with high expression and ligands that exhibit rapid internalization. However, the key characteristics of ligand-receptor sets involved in the postinternalization process remain largely unclear. In this study, we investigated the effect of ligand-receptor binding dissociation under low pH conditions, known as a postendocytic environment. Specifically, we chemically synthesized several modified epidermal growth factor (EGF) ligands that showed a variety of binding activities to the EGF receptor (EGFR) at low pH. Among these modified ligands, the siRNA conjugate with chemically synthesized EGF H10Y/H16Y, which is a less pH-responsive variant, exhibited reduced internalization and mRNA knockdown activity at high concentrations in EGFR-expressing cells. Additionally, we explored the use of antibody-related molecules (anti-EGFR IgG and Fab) as targeting moieties for siRNA conjugates. The anti-EGFR Fab-siRNA, which showed dissociation of EGF under low pH conditions, demonstrated stronger internalization and mRNA knockdown activity compared to the anti-EGFR IgG-siRNA, which strongly binds EGF at low pH. These data emphasize the importance of intracellular ligand-receptor dissociation and provide insights for future advancements in the field.

Immunotherapy engagement in pancreatic adenocarcinoma: Provisional results of iLSTA study— Durvalumab, LSTA1 (certepetide), gemcitabine, and nab-paclitaxel for locally advanced pancreatic ductal adenocarcinoma.

746 Background: Pancreatic ductal adenocarcinoma (PDAC) is characterised by a dense, extracellular matrix-rich stroma, which creates a physical barrier against drug penetration. Evidence suggests that the iRGD peptide, LSTA-1, can increase the penetration of anti-cancer drugs to tumours through selective targeting of tumour endothelial cell receptors. Additionally, LSTA-1 administration promotes CD8+ immune cell tumour infiltration, potentially enabling immunotherapy as a treatment modality. iLSTA examined safety, tolerability and effect of the combination. Methods: Participants diagnosed with locally advanced PDAC were divided into 3 cohorts in a 1:1:4 ratio. Cohort 1 (n=5) received gemcitabine (1000mg/m 2 ), nab-paclitaxel (125mg/m 2 ), placebo LSTA-1 (3.2mg/kg) and placebo durvalumab (750mg). Cohort 2 (n=5) received gemcitabine, nab-paclitaxel, active and placebo LSTA-1, and placebo durvalumab. Cohort 3 (n=20) received gemcitabine, nab-paclitaxel, LSTA-1 and durvalumab. Tissue biopsies via endoscopic ultrasound were obtained pre-treatment and between weeks 12 and 16 for analysis of tumour infiltrating lymphocytes (TILs). Patient tumour sizes were assessed every 8 weeks using radiological imaging according to RECIST v1.1, and serum CA19-9 levels were analysed monthly. Results: 6/17 patients showed significant RECIST partial response after 2 cycles of treatment (5 patients in cohort 3), with the remaining 11 patients exhibiting stable disease. After 4 cycles of treatment, 10/17 patients demonstrated partial response (9 patients in cohort 3). Of the remaining 7 patients, 6 demonstrated stable disease, and 1 patient (cohort 2) exhibited a RECIST complete response. 13/17 patients who completed 4 treatment cycles showed a decrease in CA19-9 levels. 6 patients demonstrated >90% reduction in CA19-9 (5 in cohort 3), with the remaining 7 patients showing a >50% reduction in CA19-9 levels (5 in cohort 3). 12 patients underwent repeat biopsies 12-16 weeks post-treatment to assess TILs. 10 patients showed immune cell infiltration (5% to 50% stroma infiltration), 2 had no tumour found (Cohort 3). The combination was safe with no unexpected toxicities. Conclusions: The preliminary results of this study suggest that the combination of gemcitabine and nab-paclitaxel with LSTA-1 and durvalumab is safe and potentially induces tumour infiltrating lymphocytes and RECIST response in locally advanced pancreatic adenocarcinomas. Clinical trial information: ACTRN12623000223639 .

Binding Affinity and Functional Activity of 24 Emerging Cannabinoids at the CB1 Receptor and Safety-Related Targets

Binding Affinity and Functional Activity of 24 Emerging Cannabinoids at the CB1 Receptor and Safety-Related Targets

Converting TCR-based chimeric antigen receptor STAR into dual-specific targeting receptor for cancer immunotherapy

Converting TCR-based chimeric antigen receptor STAR into dual-specific targeting receptor for cancer immunotherapy

Biomimetic membrane-coated nanoparticles specially permeate the inflammatory blood-brain barrier to deliver plasmin therapy for brain metastases.

Many brain-targeting drug delivery strategies have been reported to permeate the blood-brain barrier (BBB) via hijacking receptor-mediated transport. However, these receptor-based strategies could mediate whole-brain BBB crossing due to the wide intracranial expression of target receptors and lead to unwanted accumulation and side effects on healthy brain tissues. Inspired by brain metastatic processes and the selectivity of brain metastatic cancer cells for the inflammatory BBB, a biomimetic nanoparticle was developed by coating drug-loaded core with the inflammatory BBB-seeking erythrocyte-brain metastatic hybrid membrane, which can resist homotypic aggregation and specially bind and permeate the inflammatory BBB for specific drug delivery. Dexamethasone and embelin were used as model drugs to be loaded in the biomimetic nanoparticles to restore plasmin-mediated attacks against brain metastases. The drug-loaded nanoparticles were proved to inhibit tumor serpin secretion to restore local plasmin production, which could inactivate tumor cell surface L1CAM to inhibit vessel-spreading-dependent tumor growth and produce lethal soluble factor-related apoptosis ligands (sFasL) to induce tumor cell apoptosis, leading to the suppression of the intracranial metastatic nodule development and prolonged survival of mice with brain metastases. The inflammatory BBB-seeking biomimetic approach represents an effective regimen for potent therapy against brain metastases.

P-775. Unlocking Synergistic Potency: Dual Action of β-Lactam and β-Lactamase Inhibitor in Combating Mycobacterium abscessus through β-Lactamase Inhibition and Multi-Target Receptor Inactivation

Abstract Background Mycobacterium abscessus (Mab) poses significant clinical challenges, leading to chronic pulmonary disease in immunocompromised patients. Current treatment involve amikacin (AMK), which is toxic, highlighting the imperative for safer options. This study continues our evaluation of the synergistic effects of a β-lactam and β-lactamase inhibitor (BL/BLI) against Mab and to elucidate the underlying mechanism. The inhibition constant (Ki,app) Methods The binding affinities and chemical interactions between target receptors (LDT1-5, DDC, PBP B, and PBP-lipo) and BL/BLI were determined via kinetics, mass spectrometry, DSF, flow cytometry and microscopy. The synergistic effects of BL/BLI were evaluated in time-kill studies, conducted over 10 days, using ATCC 19977 producing BlaMab. Time-kill curves of monotherapy or double β-lactams (A, D, and G) and their combinations with avibactam (B, E, and H) or durlobactam+sulbactam (C, F, and I). Results Imipenem (IPM) showed high binding affinities for both LDTs and PBPs, with an extremely low inhibition constant (Ki,app; Tab. 1). Cephalosporins exhibited moderate binding affinity for both LDTs and PBPs, whereas amoxicillin (AMX) selectively targeted PBPs. The inactivation of BlaMab and LDTs/PBPs by durlobactam (DUR) exhibited greater efficacy compared to avibactam (AVI), aligning with their respective bactericidal effects. DUR showed a 75-fold lower Ki,app for BlaMab in comparison to AVI. The Ki,app of DUR for PBP B, PBP-lipo, and LDT2 fell below the clinical concentration, whereas those of AVI did not. Single β-lactam treatment resulted in minimal killing (∼1 log10 reduction), but adding AVI significantly enhanced killing by inhibition of β-lactamase (∼4 log10 reduction for IPM+AVI and ∼2 log10 reduction for others; Fig. 1). DUR alone showed 2 log10 reduction, and when combined with IPM or dual BL, it achieved near-eradication, surpassing the SOC (AMK + Clarithromycin + IPM or cefoxitin). Inhibition of PBP-lipo by sulopenem, IPM, DUR, and AMX changed the cell morphology to filaments. In accordance with the binding affinity to LDTs and PBPs, alterations in melting temperature were detected. Conclusion IPM + DUR + SUL showed the most killing of Mab with limited regrowth. This outcome can be attributed to β-lactamase inhibition and the inactivation of multiple targets, not only LDTs but also PBPs. This combination strategy holds promise for enhanced efficacy of Mab treatment, necessitating further study in clinical trials. Disclosures All Authors: No reported disclosures

Anti-Proliferative Activity of Ethylenediurea Derivatives with Alkyl and Oxygen-Containing Groups as Substituents

Background/Objectives: Natural cytokinins are a promising group of anti-tumor agents. In this work, we hypothesized that modification of the ethylenediurea moiety with alkyl and oxygen-containing groups could be a way to enhance the anti-proliferative properties of the molecule. Methods: Ten new analogs of ethylenediurea with these substitutions were tested for anti-proliferative activity in the human cancer cell lines MDA-MB-231 (breast cancer), A-375 (melanoma), and U-87 MG (glioblastoma) during 72 h of incubation using resazurin test and evaluated the substances receptor using molecular docking. Results: The compound with the carbamate link and ethylene substituent on the phenyl ring inhibited proliferation in these models by 70–90% without cytotoxic effects. The compound did not affect the viability of the immortalized fibroblast cell line Bj-5ta. The compound was also able to enhance the action of doxorubicin and temozolomide by about 20%. According to the molecular modeling data, the probable receptor target for the synthesized compound was the A2AR adenosine receptor. Conclusions: The results obtained on the ethylenediurea analogs with ethyl substituent in the aromatic ring are promising for the development of novel anticancer therapeutics.

A Review Report on Antihypertensive Drug

Successful treatment of hypertension is possible with limited side effects given the availability of multiple antihypertensive drug classes. This review describes the various pharmacological classes of antihypertensive drugs, under two major aspects: their mechanisms of action and side effects. The mechanism of action is analysed through a pharmacological approach, i.e. the molecular receptor targets, the various sites along the arterial system, and the extra-arterial sites of action, in order to better understand in which type of hypertension a given pharmacological class of antihypertensive drug is most indicated. In addition, side effects are described and explained through their pharmacological mechanisms, in order to better understand their mechanism of occurrence and in which patients drugs are contra-indicated. This review does not address the effectiveness of monotherapies in large randomized clinical trials and combination therapies, since these are the matters of other articles of the present issue. Five major pharmacological classes of antihypertensive drugs are detailed here: beta-blockers, diuretics, angiotensin converting enzyme inhibitors, angiotensin II receptor antagonists, and calcium channel blockers. Four additional pharmacological classes are described in a shorter manner: renin inhibitors, alpha- adrenergic receptor blockers, centrally acting agents, and direct acting vasodilators

Molecular simulation of newly designed Mannich-based ciprofloxacin derivative as the promising scaffold for E. coli dihydropteroate synthase and DNA gyrase inhibitor

The increasing incidence of bacterial infections has led to rise in antimicrobial resistance (AMR), a significant concern in public health across the globe. Henceforth, there is an urgency to address the AMR catastrophe, including developing new antibiotics, promoting the appropriate use of existing antibiotics, and investing more in research and development. Development of potent antibiotic derivatives is the call of the day. Herein, we designed a novel series of ciprofloxacin derivatives joined with sulfa-drugs (CIS1-15) and screened them against E. coli Dihydropteroate synthase and DNA gyrase through molecular docking and molecular dynamics (MD) simulations. MD simulation displayed the dynamics stability of the top-ranked docked poses, while flexibility and low-energy conformational states of these complexes the dynamics stability of the top-ranked docked poses. In contrast, the flexibility and low-energy conformational states of these complexes were inferred using principal component analysis and free energy landscape analysis. The derivatives of CIS2, CIS3, CIS5, CIS6, CIS8 and CIS15 showed strong binding affinity against both the target receptors with retention of conformational stability during MD. Pre- and post-MD snapshots show the crucial role of Arg63, Arg1072, Gly1073, and Val71 residues in the recognition of ciprofloxacin derivatives. Our in-depth structural study advocates that CIS5 and CIS6 could effectively inhibit DNA gyrase and dihydropteroate synthase. Overall, our comprehensive computational approach employed in this study establishes a benchmark for the identification of physiologically significant small molecules against emerging drug targets to design drugs based on their structure and locating potent drug-like molecules with promise for antibacterial potential.

Computational Design of a Multi-Epitope Vaccine against Prevotella copri: Molecular Dynamics and Immunoinformatics Study

Prevotella copri is a prominent constituent of the human gastrointestinal microbiome, and its fluctuating abundance has been linked with positive and negative influences on diseases such as Parkinson’s disease and rheumatoid arthritis. Prevotella copri demonstrates flexibility against drugs. There is presently no vaccine approved by the FDA against prevotella copri,and treatment options are restricted. Hence, this research work was designed to create an in silico-based vaccine for prevotella copri.The protein sequences of two distinct strains ofprevotella copriwere retrieved from NCBI. The T-cell and B-cell epitopes were obtained and then analyzed for antigenicity, allergenicity, docking and simulation. The peptide comprises linear B-cell and T-cell epitopes from proteins identified as potential novel vaccine candidates. The molecular dynamics (MD) simulations and protein-protein docking results revealed that the vaccine exhibits strong and Sustained interaction with Toll-like receptor 4 (TLR4). The constructed sequence was integrated into the pET-30a (+) biological vehicle (vector) for subsequent analysis expression in E. coli through the SnapGene server. The constructed multi-epitopic vaccine candidate was assessed for its structural, physicochemical and immunological properties. The results demonstrated solubility, stability, antigenicity and nonallergenicity and showed a strong affinity for its target receptors. The in silico study represents a significant step forward in designing a vaccine that could effectively eliminate Prevotella copri globally.

Evaluating TcAs for Use in Biotechnology Applications

ABC toxin complexes (Tcs) are tripartite complexes that come together to form nano-syringe-like translocation systems. ABC Tcs are often compared with Bacillus thuringiensis (Bt) toxins, and as such, they have been highly studied as a potential novel pesticide to combat growing insect resistance. Moreover, it is possible to substitute the cytotoxic hypervariable region with alternative peptides, which promise potential use as a novel peptide delivery system. These toxins possess the unique ability to form active chimeric holotoxins across species and display the capability to translocate a variety of payloads across membrane bilayers. Additionally, mutagenesis on the linker region and the receptor binding domains (RBDs) show that mutations do not inherently cause a loss of functionality for translocation. For these reasons, Tcs have emerged as an ideal candidate for targeted protein engineering. However, elucidation of the specific function of each RBD in relation to target receptor recognition currently limits the use of a rational design approach with any ABC Tc. Additionally, there is a distinct lack of targeting and biodistribution data for many Tcs among mammals and mammalian cell lines. Here, we outline two separate strategies for modifying the targeting capabilities of the A subunit (TcA) from Xenorhabdus nematophilus, Xn-XptA2. We identify novel structural differences that make Xn-XptA2 different than other characterized TcAs and display the modular capabilities of substituting RBDs from alternative TcAs into the Xn-XptA2 scaffold. Finally, we show the first, to our knowledge, biodistribution data of any TcA in mice.

Identification and validation of a T cell receptor targeting KRAS G12V in HLA-A*11:01 pancreatic cancer patients.

T cells targeting a KRAS mutation can induce durable tumor regression in some patients with metastatic epithelial cancer. It is unknown whether T cells targeting mutant KRAS that are capable of killing tumor cells can be identified from peripheral blood of patients with pancreatic cancer. We developed an in vitro stimulation approach and identified HLA-A*11:01-restricted KRAS G12V-reactive CD8+ T cells and HLA-DRB1*15:01-restricted KRAS G12V-reactive CD4+ T cells from peripheral blood of 2 out of 6 HLA-A*11:01-positive patients with pancreatic cancer whose tumors expressed KRAS G12V. The HLA-A*11:01-restricted KRAS G12V-reactive T cell receptor (TCR) was isolated and validated to specifically recognize the KRAS G12V8-16 neoepitope. While T cells engineered to express this TCR specifically recognized all 5 tested human HLA-A*11:01+ and KRAS G12V+ pancreatic cancer organoids, the recognition was often modest, and tumor cell killing was observed in only 2 out of 5 organoids. IFN-γ priming of the organoids enhanced the recognition and killing by the TCR-engineered T cells. The TCR-engineered T cells could significantly slow the growth of an established organoid-derived xenograft in immunodeficient mice. Our data suggest that this TCR has potential for use in TCR-gene therapy, but additional strategies that enhance tumor recognition by the TCR-engineered T cells likely will be required to increase clinical activity.

Design, synthesis, anti-inflammatory evaluation, and molecular docking studies of novel quinazoline-4(3H)-one-2-carbothioamide derivatives.

In this paper, a series of novel quinazoline-4(3H)-one-2-carbothioamide derivatives (8a-p) were designed and synthesized via the Wilgerodt-Kindler reaction between 2-methylquinazoline-4-one 10 and amines using S8/DMSO as the oxidizing system. Their characteristics were confirmed by IR, NMR, HRMS spectra, and their melting point. These novel derivatives (8a-p) were evaluated for their anti-inflammatory activity by inhibiting NO production in lipopolysaccharide (LPS)-activated RAW 264.7 macrophage cells. Compounds 8d (IC50 = 2.99 μM), 8g (IC50 = 3.27 μM), and 8k (IC50 = 1.12 μM) exhibited potent inhibition of NO production compared to the standard drug dexamethasone (IC50 = 14.20 μM). Compound 8a (IC50 = 13.44 μM) exhibited NO inhibition comparable to dexamethasone. Structure-activity relationship (SAR) studies indicated that the presence of both the thioamide functional group (NH-C[double bond, length as m-dash]S) directly attached to the phenyl ring containing halogen substituents (4-Cl, 8d), (4-Br, 8g) and (4-CF3, 8k), is responsible for the potent anti-inflammatory activity of these novel quinazolinone derivatives. Computational modeling studies revealed that compounds 8d, 8g, and 8k are potent inhibitors of TLR4 signaling through the formation of hydrophobic interactions and are stabilized by hydrogen bonds. Replacing the thioamide (8k) with an amide (8q) resulted in an 83-fold decrease in NO inhibitory potency. This highlights the important role of H-bonding involving the thioamide group. The structural shape difference results in favorable interactions of quinazolinones containing thioamide linkers compared to amide linkers to the target receptor. Furthermore, the ADMET profiles and physicochemical properties of these three lead compounds were predicted to meet the criteria for drug-like properties. Therefore, these compounds may be potential candidates for the treatment of many inflammatory diseases associated with immune disorders.

DOP029 SPP1 in colitis-associated colon cancer

Abstract Background Colitis-associated carcinoma (CAC) is a major complication that arises in patients with a long-standing ulcerative colitis (UC) and Crohn’s disease (CD). Albeit numerous studies report mutational landscape of CAC, its transcriptomic landscape is poorly understood. Thus, to interrogate the tumour ecology & mechanisms behind CAC development, we adopted a muti-modal approach utilizing FFPE tissues from human CAC patients and colon organoids. We leveraged immunology bulk gene expression and spatial gene expression to derive a robust gene signature of CAC at a single cell resolution. Methods To comprehensively profile the CAC immune microenvironment, we created a comprehensive dataset (Nanostring) covering relevant clinical FFPE samples encompassing 40 patients suffering from either IBD or CAC, alongside inflammation-free healthy controls (10 patients/group). We observed a robust upregulation of the SPP1 (Secreted Phosphoprotein 1) gene encoding osteopontin (OPN) in CAC. Subsequently, we extended our methodology to spatially resolved transcriptomics (Xenium) using 5μm FFPE sections from CAC & UC patients (3 patients/group). This provided insights into the spatial and single cell expression of SPP1 and its target receptors at a subcellular resolution. Furthermore, we mapped the ligand-receptor pairs onto cell types to uncover SPP1 signalling in CAC. These findings were validated at a protein level by whole FFPE section confocal microscopy. Results Immunology gene expression (Nanostring) dataset revealed a strong upregulation of SPP1 gene encoding OPN in CAC as compared to UC and CD. Spatially resolved transcriptomics (Xenium) unveiled the spatial heterogeneity of SPP1 expression in CAC, that is primarily arising from CD68+ CD163+ macrophages in CAC (Fig 1B), validated through OPN/CD68 immunostainings. Ligand-receptor (LR) analysis revealed a distinct LR pairing focusing on SPP1, that is secreted (outgoing signal) macrophages to T cells (as incoming signal) via upregulated integrin and CD44-receptors (Fig 1D/E). Furthermore, CAC tumour cells surrounding the SPP1+ macrophages exhibited a distinct gene expression signature associated with T cell exclusion and immunosuppression in CAC (Fig 1C/FG). Conclusion We identified a CAC specific upregulation of SPP1 at both RNA and protein levels, expressed by CD68+ CD163+ macrophages. Mutually exclusive spatial location of SPP1/OPN+ macrophages and CD8+ T cells suggests a crucial indirect role of SPP1/OPN in mediating an immunosuppressive tumour microenvironment. We further uncovered CAC specific, single cell gene expression signature that has the potential to identify pre-malignant stages of CAC.

Phytochemical investigation, role in wound healing process and cytotoxicity of Sphagneticola trilobata: In vitro, in vivo and in silico approach.

Sphagneticola trilobata was traditionally used to alleviate wounds using topical plant preparations. The precise mechanism of the plant responsible for its wound healing effect are still unclear. Although the plant was reported to be cytotoxic, there is a lack of reported data regarding its cytotoxic impact on skin cancer. To in-depth investigate wound healing and cytotoxic effects of the plant extracts and its fractions by using different assays. In vitro scratch assay and in vivo full-thickness wound model were performed to evaluate the plant's wound healing activity. Enzyme-linked immunosorbent assay kits were employed to assess key skin parameters levels. The cytotoxicity was evaluated using in vitro Western Standard Time assay against skin carcinoma cells. Sphagneticola trilobata improved the wound closure percentage in both in vitro scratch assay and in vivo model by modulating inflammation, as evidenced by a reduction in tumor necrosis factor and mitogen activated protein kinase levels, and enhancing proliferation via elevating collagen, smooth muscle actin, and forkhead protein. The total extract's efficacy surpassed the effectiveness of reference ointment. The non-polar fraction outperformed the polar one in accelerating wound closure and improving the tested skin parameters levels. Trilobolide-6-O-isobutyrate displayed the best docking scores for the selected target receptors. Moreover, the non-polar fraction demonstrated the most powerful cytotoxic effect against skin cancer cells. A specific compound mixture (kaurenoic acid/grandiflorenic acid, 1 and 2) within this fraction exhibited stronger cytotoxicity. Sphagneticola trilobata can be considered as a promising therapeutic agent in relieving wounds and combating skin cancer cell lines.

Pretransplant targeting of TNFRSF25 and CD25 stimulates recipient Tregs in target tissues ameliorating GVHD post-HSCT.

The current approach to minimize transplant-associated complications, including graft-versus-host disease (GVHD) includes long-term pharmacological immune suppression frequently accompanied by unwanted side effects. Advances in targeted immunotherapies regulating alloantigen responses in the recipient continue to reduce the need for pan-immunosuppression. Here, in vivo targeting of the TNF superfamily receptor 25 (TNFRSF25) and the high affinity IL-2 receptor with a TL1A-Ig fusion protein and low dose IL-2, respectively, was used to pretreat recipient mice prior to allogeneic-HSCT (aHSCT). Pretreatment induced Treg expansion persisting early post-aHSCT leading to diminished GVHD and improved transplant outcomes. Expansion was accompanied by an increase in frequency of stable and functionally active Tregs as evidenced by in vitro assays using cells from major GVHD target tissues including colon, liver, and eye. Importantly, pretreatment supported epithelial cell function/integrity, a diverse microbiome including reduction of pathologic bacteria overgrowth and promotion of butyrate producing bacteria, while maintaining physiologic levels of obligate/facultative anaerobes. Notably, using a sphingosine 1-phosphate receptor agonist to sequester T cells in lymphoid tissues, we found that the increased tissue Treg frequency included resident CD69 + CD103 + FoxP3 + hepatic Tregs. In contrast to infusion of donor Treg cells, the strategy developed here resulted in the presence of immunosuppressive target tissue environments in the recipient prior to the receipt of donor allo-reactive T cells and successful perseveration of GVL responses. We posit strategies that circumvent the need of producing large numbers of ex-vivo manipulated Tregs, may be accomplished through in vivo recipient Treg expansion, providing translational approaches to improve aHSCT outcomes.

Identification of Novel Progesterone Receptor (PR) Inhibitors (Homo sapiens) from Metabolites of Biotransformation Fungal: A Bioinformatics Approach

Background/Objectives: Steroids have demonstrated selective cytotoxic properties against tumor cells. The pro-gesterone receptor (PR) plays a vital role in the proliferation, cell differentiation, and maintenance of female reproductive tissue, and its malfunction can lead to breast cancer. The use of the biocatalytic method by filamentous fungi has sparked interest in the obtained of steroids due to the advantages of the process. Methods: Pharmacokinetic and toxicological properties (rat and mouse), molecular docking simulation studies, and prediction of the spectrum of biological activity were performed to select molecules with the potential for PR inhibition, from 155 biotransformed products of the progesterone. Subsequently, the chemical structures were subjected to an evaluation of their pharmacokinetic and toxicological properties and, with the application of ADMET filters. Results: Androstenedione, 17α-hydroxyprogesterone, and dihydrotestosterone, obtained by the process of biotransformation of PR by different filamentous fungi, showed good pharmacokinetic profiles and low toxicity compared to the control groups. The in-silico data associated with molecular docking studies revealed the best binding affinity and similarity in the interactions of these molecules against the human progesterone receptor target. Thus, the results of biological activity spectrum prediction highlight the great potential to investigate the role of molecular descriptors in the attribution of anti-cancer activities. Conclusions: The biocatalytic process, by filamentous fungi, can provide important molecules as a product of progesterone biotransformation, such as androstenedione, 17α-hydroxyprogesterone, and dihydrotestosterone. In this study we showed that these molecules have good pharmacokinetic profiles and low toxicity for antineoplastic activity (breast cancer).

Reactivity of Olanzapine and Tricyclic Antidepressants on the Protective Effects of Trolox on Lipid Peroxidation Evaluated Using Fluorescence Anisotropy, Electron Paramagnetic Resonance Spectrometry, and Thermal Analysis.

Multiacting receptor-targeting antipsychotics and tricyclic antidepressants stimulate various neurotransmitter receptors despite the different targets of postsynaptic receptors and presynaptic reuptake transporters. Their auxiliary and adverse effects may be caused by multiple targets or the modification of the neuronal membrane. To evaluate the membrane responses to olanzapine, imipramine, desipramine, amitriptyline, lidocaine, and dibucaine, we examined the inhibition of lipid peroxidation in egg yolk phosphatidylcholine liposomes. By contrast, their effects on membrane fluidity were measured as the suppressive contributions of the inhibitory activity of Trolox on lipid oxidation. These drugs inhibit lipid peroxidation and exclude harmful reactive oxygen species and the protective effect of Trolox. The fluorescence anisotropy of 1,6-diphenyl-1,3,5-hexatriene in saturated phospholipid liposome-containing drugs suggested that olanzapine, imipramine, and dibucaine enhanced membrane fluidity. The radical scavenging activity of 2,2-diphenylpicrylhidrazyl and galvinoxyl radicals was determined using electron paramagnetic resonance experiments, and their molecular flexibility was determined using thermograms for differential scanning calorimetry. Multiple regression analyses of the linear free energy relationship approach and comparative investigations revealed that the membranous fluidity of the liposomes, independent of the radical scavenging activity of the drugs, induced the inhibitory activity on lipid peroxidation. We discussed how these drugs act on nervous membranes and aimed to identify the relationship between uncertified functions and membranous fluidity.