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Haematologica Jun 2024Macrophages are one of the key mediators of the therapeutic effects exerted by monoclonal antibodies, such as the anti-CD19 antibody tafasitamab, approved in combination...
Macrophages are one of the key mediators of the therapeutic effects exerted by monoclonal antibodies, such as the anti-CD19 antibody tafasitamab, approved in combination with lenalidomide for the treatment of relapsed or refractory (r/r) diffuse large B cell lymphoma (DLBCL). However, antibody-dependent cellular phagocytosis (ADCP) in the tumor microenvironment can be counteracted by increased expression of the inhibitory receptor SIRPα on macrophages and its ligand, the immune checkpoint molecule CD47 on tumor cells. The aim of this study was to investigate the impact of the CD47-SIRPα axis on tafasitamabmediated phagocytosis and explore the potential of anti-CD47 blockade to enhance its antitumor activity. Elevated expression of both SIRPα and CD47 was observed in DLBCL patient-derived lymph node biopsies compared to healthy controls. CRISPR-mediated CD47 overexpression impacted tafasitamab-mediated ADCP in vitro and increased expression of SIRPα on macrophages correlated with decreased ADCP activity of tafasitamab against DLBCL cell lines. Combination of tafasitamab and an anti-CD47 blocking antibody enhanced ADCP activity of in vitro generated macrophages. Importantly, tafasitamab-mediated phagocytosis was elevated in combination with CD47 blockade using primary DLBCL cells and patient-derived lymphoma-associated macrophages (LAMs) in an autologous setting. Furthermore, lymphoma cells with low CD19 expression were efficiently eliminated by the combination treatment. Finally, combined treatment of tafasitamab and an anti-CD47 antibody resulted in enhanced tumor volume reduction and survival benefit in lymphoma xenograft mouse models. These findings provide evidence that CD47 blockade can enhance the phagocytic potential of tumor targeting immunotherapies such as tafasitamab and suggest there is value in exploring the combination in the clinic.
PubMed: 38934068
DOI: 10.3324/haematol.2023.284795 -
Nanoscale Advances Jun 2024Tumors pose a significant threat to human health, and their occurrence and fatality rates are on the rise each year. Accurate tumor diagnosis is crucial in preventing...
Tumors pose a significant threat to human health, and their occurrence and fatality rates are on the rise each year. Accurate tumor diagnosis is crucial in preventing untimely treatment and late-stage metastasis, thereby reducing mortality. To address this, we have developed a novel type of hybrid nanogel called γ-FeO@PNIPAM/PAm/CTS, which contains iron oxide nanoparticles and poly(-isopropyl acrylamide)/polyacrylamide/chitosan. The rationale for this study relies on the concept that thermosensitive PNIPAM has the ability to contract when exposed to elevated temperature conditions found within tumors. This contraction leads to a dense clustering of the high-loading γ-FeO nanoparticles within the nanogel, thus greatly enhancing the capabilities of MRI. Additionally, the amino groups in chitosan on the particle surface can be converted into ammonium salts under mildly acidic conditions, allowing for an increase in the charge of the nanogel specifically at the slightly acidic tumor site. Consequently, it promotes the phagocytosis of tumor cells and effectively enhances the accumulation and retention of nanogels at the tumor site. The synthesis of the hybrid nanogels involves a surfactant-free emulsion copolymerization process, where vinyl-modified γ-FeO superparamagnetic nanoparticles are copolymerized with the monomers in the presence of chitosan. We have optimized various reaction parameters to achieve a high loading content of the superparamagnetic nanoparticles, reaching up to 60%. The achieved value of 517.74 mM S significantly surpasses that of the clinical imaging contrast agent Resovist (approximately 151 mM S). To assess the performance of these magnetic nanogels, we conducted experiments using Cal27 oral tumors and 4T1 breast tumors in animal models. The nanogels exhibited temperature- and pH-sensitivity, enabling magnetic targeting and enhancing diagnosis through MRI. The results demonstrated the potential of these hybrid nanogels as contrast agents for magnetic targeting in biomedical applications.
PubMed: 38933853
DOI: 10.1039/d4na00014e -
The Journal of the Association of... Jun 2024Dehydration, often unnoticed, can occur in adults due to heat-related illnesses, viral infections, and upper respiratory tract infections, leading to deficits in fluids,... (Review)
Review
Dehydration, often unnoticed, can occur in adults due to heat-related illnesses, viral infections, and upper respiratory tract infections, leading to deficits in fluids, electrolytes, and energy (FEE), even without diarrhea. This fluid deficit, in turn, impairs immunity at cellular and molecular levels. Physiologically, the immune system rapidly reacts to threats by adjusting its structural permeability, allowing water and small solutes to be passed, facilitated by proteins like aquaporins (AQPs). These AQPs are also essential for immune cell communication and adjustments of the cytoskeleton for functions like chemotaxis and phagocytosis. Apart from hydration, maintaining an optimal intake of essential micronutrients, including vitamins C and E, copper, zinc, and selenium, is also critical for supporting immune function and acting as antioxidants. Transient alterations in immune function caused by acute stressors or nondiarrheal conditions heighten vulnerability to coexisting illnesses, particularly cold and upper respiratory tract infections, while also elevating the likelihood of recurrent health issues. Supplementing fluids with known FEE content according to quality standards and enhanced taste is recommended during acute illness and until complete recovery. Thus, dehydration, caused by various acute conditions, can impair immunity and delay recovery. Prioritizing hydration and nutrition in healthcare and general settings is imperative, even when diarrhea is absent.
Topics: Humans; Micronutrients; Dehydration; Fluid Therapy
PubMed: 38932732
DOI: 10.59556/japi.72.0546 -
Nutrients Jun 2024The immune system is affected by the dietary products humans intake. Immune system regulation by nutrition has uses in the clinical context, but it can also benefit... (Randomized Controlled Trial)
Randomized Controlled Trial
Prospective, Randomized, Double-Blind Parallel Group Nutritional Study to Evaluate the Effects of Routine Intake of Fresh vs. Pasteurized Yogurt on the Immune System in Healthy Adults.
The immune system is affected by the dietary products humans intake. Immune system regulation by nutrition has uses in the clinical context, but it can also benefit healthy populations by delaying or preventing the emergence of immune-mediated chronic illnesses. In this study, the purpose was to describe and compare the modulator effects on the immune system of the routine ingestion of fresh vs. pasteurized yogurt. A unicentral, prospective, randomized, double-blind, parallel group 8-week nutritional study was carried out comparing the ingestion of 125 g of the products in healthy adults three times a day. A complete battery of in vitro tests on the activity of the immune system, processes and phenomena was performed. Exclusive immune-modulatory effects of fresh yogurt with respect to base line were found in terms of increased systemic IgM (primary immune responses), increased synthesis of IFN-gamma upon stimulation (Th1) and increased peripheral T cells (mainly "naive" CD4s). In the three interventions, we observed an increased phagocytic activity and burst test in granulocytes, together with increased secretion of IL-6, IL-1 β and IL-8 (pro-inflammatory) and increased CD16 expression (FcR favoring phagocytosis) in granulocytes. Overall, it is concluded that regardless of bacteria being alive or thermally inactivated, yogurt has common effects on the innate system, but the presence of live bacteria is necessary to achieve a potentiating effect on the specific immune response.
Topics: Yogurt; Humans; Double-Blind Method; Adult; Male; Female; Prospective Studies; Pasteurization; Phagocytosis; Cytokines; Young Adult; Immunoglobulin M; Interferon-gamma; Middle Aged; Granulocytes; Immune System; Receptors, IgG
PubMed: 38931322
DOI: 10.3390/nu16121969 -
Medicina (Kaunas, Lithuania) Jun 2024: As modulators of the tumor microenvironment, macrophages have been extensively studied for their potential in developing anticancer strategies, particularly in...
: As modulators of the tumor microenvironment, macrophages have been extensively studied for their potential in developing anticancer strategies, particularly in regulating macrophage polarization towards an antitumorigenic (M1) phenotype rather than a protumorigenic (M2) one in various experimental models. Here, we evaluated the effect of PD98059, a mitogen-activated protein kinase kinase MAPKK MEK1-linked pathway inhibitor, on the differentiation and polarization of THP-1 monocytes in response to phorbol-12-myristate-13-acetate (PMA) under various culture conditions for tumor microenvironmental application. : Differentiation and polarization of THP-1 were analyzed by flow cytometry and RT-PCR. Polarized THP-1 subsets with different treatment were compared by motility, phagocytosis, and so on. : Clearly, PMA induced THP-1 differentiation occurs in adherent culture conditions more than nonadherent culture conditions by increasing CD11b expression up to 90%, which was not affected by PD98059 when cells were exposed to PMA first (post-PD) but inhibited when PD98059 was treated prior to PMA treatment (pre-PD). CD11b THP-1 cells treated with PMA and PMA-post-PD were categorized into M0 (HLA-DR and CD206), M1 (HLA-DR and CD206), and M2 (HLA-DR and CD206), resulting in an increased population of M1 macrophages. The transcription levels of markers of macrophage differentiation and polarization confirmed the increased M1 polarization of THP-1 cells with post-PD treatment rather than with PMA-only treatment. The motility and cytotoxicity of THP-1 cells with post-PD treatment were higher than THP-1 cells with PMA, suggesting that post-PD treatment enhanced the anti-tumorigenicity of THP-1 cells. Confocal microscopy and flow cytometry showed the effect of post-PD treatment on phagocytosis by THP-1 cells. : We have developed an experimental model of macrophage polarization with THP-1 cells which will be useful for further studies related to the tumor microenvironment.
Topics: Humans; Macrophages; Tetradecanoylphorbol Acetate; Flavonoids; THP-1 Cells; Cell Differentiation; Monocytes; Flow Cytometry; Phagocytosis
PubMed: 38929626
DOI: 10.3390/medicina60061009 -
Animals : An Open Access Journal From... Jun 2024MafB is a transcription factor that regulates macrophage differentiation. Macrophages are a traditional feature of the hamster Harderian gland (HG); however, studies...
MafB is a transcription factor that regulates macrophage differentiation. Macrophages are a traditional feature of the hamster Harderian gland (HG); however, studies pertaining to MafB expression in the HG are scant. Here, the full-length cDNA of the gene in hamsters was cloned and sequenced. Molecular characterization revealed that MafB encodes a protein containing 323 amino acids with a DNA-binding domain, a transactivation domain, and a leucine zipper domain. qPCR assays indicated that MafB was expressed in different tissues of both sexes. The highest relative expression levels in endocrine tissues were identified in the pancreas. Gonadectomy in male hamsters was associated with significantly higher mRNA levels in the HG; replacement with dihydrotestosterone restored mRNA expression. The HG in male hamsters contained twofold more MafB mRNA than the HG of female hamsters. Adrenals revealed similar mRNA relative expression levels during the estrous cycle. The estrous phase was associated with higher mRNA levels in the ovary. A significantly up-regulated expression and sexual dimorphism of MafB was found in the pancreas. Therefore, MafB in the HG may play an active role in the macrophage differentiation required for phagocytosis activity and intraocular repair. Additionally, sex steroids appear to strongly influence the MafB expression in the HG and pancreas. These studies highlight the probable biological importance of MafB in immunological defense and pancreatic β cell regulation.
PubMed: 38929347
DOI: 10.3390/ani14121728 -
Antioxidants (Basel, Switzerland) May 2024This study aims to investigate the role of microRNA let-7f in the dysfunction and degeneration of retinal pigment epithelium (RPE) cells through the induction of...
This study aims to investigate the role of microRNA let-7f in the dysfunction and degeneration of retinal pigment epithelium (RPE) cells through the induction of senescence and oxidative stress. Furthermore, we explore whether let-7f inhibition can protect these cells against sodium iodate (SI)-induced oxidative stress. Oxidative stress and let-7f expression are reciprocally regulated in retinal pigment epithelial cells. Overexpression of let-7f in ARPE-19 cells induced oxidative stress as demonstrated by increased reactive oxygen species (ROS) production as well as senescence. Inhibition of let-7f successfully protected RPE cells from the detrimental effects induced by SI. In addition, let-7f overexpression induced RPE cellular dysfunction by diminishing their migratory capabilities and reducing the phagocytosis of porcine photoreceptor outer segments (POS). Results were further confirmed in vivo by intravitreal injections of SI and let-7f antagomir in C57BL/6 mice. Our results provide strong evidence that let-7f is implicated in the dysfunction of RPE cells through the induction of senescence and oxidative injury. These findings may help to uncover novel and relevant processes in the pathogenesis of dry AMD.
PubMed: 38929085
DOI: 10.3390/antiox13060646 -
International Journal of Molecular... Jun 2024Among the myriad of existing tyrosine kinase receptors, the TAM family-abbreviated from Tyro3, Axl, and Mer tyrosine kinase (MerTK)-has been extensively studied with an...
Among the myriad of existing tyrosine kinase receptors, the TAM family-abbreviated from Tyro3, Axl, and Mer tyrosine kinase (MerTK)-has been extensively studied with an outstanding contribution from the team of Prof. Greg Lemke. MerTK activity is implicated in a wide variety of functions involving the elimination of apoptotic cells and has recently been linked to cancers, auto-immune diseases, and atherosclerosis/stroke. In the retina, MerTK is required for the circadian phagocytosis of oxidized photoreceptor outer segments by the retinal-pigment epithelial cells, a function crucial for the long-term maintenance of vision. We previously showed that MerTK ligands carry the opposite role in vitro, with Gas6 inhibiting the internalization of photoreceptor outer segments while Protein S acts conversely. Using site-directed mutagenesis and ligand-stimulated phagocytosis assays on transfected cells, we presently demonstrate, for the first time, that Gas6 and Protein S recognize different amino acids on MerTK Ig-like domains. In addition, MerTK's function in retinal-pigment epithelial cells is rhythmic and might thus rely on the respective stoichiometry of both ligands at different times of the day. Accordingly, we show that ligand bioavailability varies during the circadian cycle using RT-qPCR and immunoblots on retinal and retinal-pigment epithelial samples from control and beta5 integrin knockout mice where retinal phagocytosis is arrhythmic. Taken together, our results suggest that Gas6 and Protein S might both contribute to refine the acute regulation of MerTK in time for the daily phagocytic peak.
Topics: c-Mer Tyrosine Kinase; Phagocytosis; Animals; Intercellular Signaling Peptides and Proteins; Protein S; Humans; Retina; Mice; Circadian Rhythm; Ligands; Retinal Pigment Epithelium; Receptor Protein-Tyrosine Kinases
PubMed: 38928335
DOI: 10.3390/ijms25126630 -
International Journal of Molecular... Jun 2024CD147 is upregulated in cancers, including aggressive T-ALL. Traditional treatments for T-ALL often entail severe side effects and the risk of relapse, highlighting the...
Engineered CD147-Deficient THP-1 Impairs Monocytic Myeloid-Derived Suppressor Cell Differentiation but Maintains Antibody-Dependent Cellular Phagocytosis Function for Jurkat T-ALL Cells with Humanized Anti-CD147 Antibody.
CD147 is upregulated in cancers, including aggressive T-ALL. Traditional treatments for T-ALL often entail severe side effects and the risk of relapse, highlighting the need for more efficacious therapies. ADCP contributes to the antitumor response by enhancing the ability of phagocytic cells to engulf cancer cells upon antibody binding. We aimed to engineer CD147 THP-1 cells and evaluated their differentiation properties compared to the wild type. A humanized anti-CD147 antibody, HuM6-1B9, was also constructed for investing the phagocytic function of CD147 THP-1 cells mediated by HuM6-1B9 in the phagocytosis of Jurkat T cells. The CD147 THP-1 was generated by CRISPR/Cas9 and maintained polarization profiles. HuM6-1B9 was produced in CHO-K1 cells and effectively bound to CD147 with high binding affinity (K: 2.05 ± 0.30 × 10 M). Additionally, HuM6-1B9 enhanced the phagocytosis of Jurkat T cells by CD147 THP-1-derived LPS-activated macrophages (M-LPS), without self-ADCP. The formation of THP-1-derived mMDSC was limited in CD147 THP-1 cells, highlighting the significant impact of CD147 deletion. Maintaining expression markers and phagocytic function in CD147 THP-1 macrophages supports future engineering and the application of induced pluripotent stem cell-derived macrophages. The combination of HuM6-1B9 and CD147 monocyte-derived macrophages holds promise as an alternative strategy for T-ALL.
Topics: Humans; Phagocytosis; Jurkat Cells; Basigin; Cell Differentiation; THP-1 Cells; Myeloid-Derived Suppressor Cells; Antibodies, Monoclonal, Humanized; Animals; CHO Cells; Cricetulus; Monocytes; Macrophages; CRISPR-Cas Systems
PubMed: 38928332
DOI: 10.3390/ijms25126626 -
Biomedicines Jun 2024Nerve injury is a common condition that occurs as a result of trauma, iatrogenic injury, or long-lasting stimulation. Unlike the central nervous system (CNS), the... (Review)
Review
Nerve injury is a common condition that occurs as a result of trauma, iatrogenic injury, or long-lasting stimulation. Unlike the central nervous system (CNS), the peripheral nervous system (PNS) has a strong capacity for self-repair and regeneration. Peripheral nerve injury results in the degeneration of distal axons and myelin sheaths. Macrophages and Schwann cells (SCs) can phagocytose damaged cells. Wallerian degeneration (WD) makes the whole axon structure degenerate, creating a favorable regenerative environment for new axons. After nerve injury, macrophages, neutrophils and other cells are mobilized and recruited to the injury site to phagocytose necrotic cells and myelin debris. Pro-inflammatory and anti-inflammatory factors involved in the inflammatory response provide a favorable microenvironment for peripheral nerve regeneration and regulate the effects of inflammation on the body through relevant signaling pathways. Previously, inflammation was thought to be detrimental to the body, but further research has shown that appropriate inflammation promotes nerve regeneration, axon regeneration, and myelin formation. On the contrary, excessive inflammation can cause nerve tissue damage and pathological changes, and even lead to neurological diseases. Therefore, after nerve injury, various cells in the body interact with cytokines and chemokines to promote peripheral nerve repair and regeneration by inhibiting the negative effects of inflammation and harnessing the positive effects of inflammation in specific ways and at specific times. Understanding the interaction between neuroinflammation and nerve regeneration provides several therapeutic ideas to improve the inflammatory microenvironment and promote nerve regeneration.
PubMed: 38927464
DOI: 10.3390/biomedicines12061256