Surface Expression Research Articles

Synchronous motion of the Easter mantle plume and the East Pacific Rise

AbstractThe Easter mantle plume has produced one of the longest hotspot tracks in the Pacific Ocean. While previous studies have focused on the eastern side extending across the Nazca Plate, we use 40Ar/39Ar isotopic and geochemical data to investigate the less explored western side around the Easter Microplate. We propose a dynamic model in which a deeper (600 km-depth), less buoyant mantle exerts a westward force on the East Pacific Rise (EPR), while a more buoyant plume region drives Easter hotspot volcanism and a localised acceleration in seafloor spreading. Our findings suggest that the Easter hotspot is the more focused surface expression of the most buoyant region of a vast, deep-seated mantle plume extending from the Pacific Large Low Shear Velocity Province (LLSVP). This challenges the traditional view of hotspots as isolated phenomena and suggests they are part of broader LLSVP-related mantle structures. Our results imply a more intricate, large-scale relationship between hotspots, mantle plumes, spreading ridges, and mantle dynamics.

Palmitoylation of TIM-3 promotes immune exhaustion and restrains antitumor immunity.

T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) is an immune checkpoint that has critical roles in immune exhaustion. However, little is known about the mechanisms that regulate TIM-3 surface expression and turnover. Here, we report that human TIM-3 is palmitoylated by the palmitoyltransferase DHHC9 at residue cysteine 296 (Cys296). Palmitoylation stabilized TIM-3 by preventing binding to E3 ubiquitin ligase HRD1, thereby suppressing its polyubiquitination and degradation. DHHC9 knockdown attenuated chimeric antigen receptor T (CAR-T) cell exhaustion, and a peptidic inhibitor of TIM-3 palmitoylation accelerated TIM-3 degradation and enhanced antitumor immunity mediated by CAR-T cells and natural killer (NK) cells. In hepatocellular carcinoma, DHHC9 expression correlated with TIM-3 expression in CD8+ T cells and NK cells, and high DHHC9 expression was associated with shorter survival in patients with high TIM-3. These findings demonstrate that palmitoylation of TIM-3 catalyzed by DHHC9 promotes its stability, resulting in immune exhaustion and impaired antitumor immunity.

A tetraspecific engager armed with a non-alpha IL-2 variant harnesses natural killer cells against B cell non-Hodgkin lymphoma.

NK cells offer a promising alternative to T cell therapies in cancer. We evaluated IPH6501, a clinical-stage, tetraspecific NK cell engager (NKCE) armed with a non-alpha IL-2 variant (IL-2v), which targets CD20 and was developed for treating B cell non-Hodgkin lymphoma (B-NHL). CD20-NKCE-IL2v boosts NK cell proliferation and cytotoxicity, showing activity against a range of B-NHL cell lines, including those with low CD20 density. Whereas it presented reduced toxicities compared with those commonly associated with T cell therapies, CD20-NKCE-IL2v showed greater killing efficacy over a T cell engager targeting CD20 in in vitro preclinical models. CD20-NKCE-IL2v also increased the cell surface expression of NK cell-activating receptors, leading to activity against CD20-negative tumor cells. In vivo studies in nonhuman primates and tumor mouse models further validated its efficacy and revealed that CD20-NKCE-IL2v induces peripheral NK cell homing at the tumor site. CD20-NKCE-IL2v emerges as a potential alternative in the treatment landscape of B-NHL.

Astrocytic NHERF-1 Increases Seizure Susceptibility by Inhibiting Surface Expression of TREK-1.

Mature hippocampal astrocytes exhibit a linear current-to-voltage (I-V) K+ membrane conductance called passive conductance. It is estimated to enable astrocytes to keep potassium homeostasis in the brain. We previously reported that the TWIK-1/TREK-1 heterodimeric channels are crucial for astrocytic passive conductance. However, the regulatory mechanism of these channels by other binding proteins remains elusive. Here, we identified Na+/H+ exchange regulator-1 (NHERF-1), a protein highly expressed in astrocytes, as a novel interaction partner for these channels. NHERF-1 endogenously bound to TWIK-1/TREK-1 in hippocampal cultured astrocytes. When NHERF-1 is overexpressed or silenced, surface expression and activity of TWIK-1/TREK-1 heterodimeric channels are inhibited or enhanced, respectively. Furthermore, we confirmed that reduced astrocytic passive conductance by NHERF-1 overexpressing in the hippocampus increases kainic acid (KA)-induced seizure sensitivity. Taken together, these results suggest that NHERF-1 is a key regulator of TWIK-1/TREK-1 heterodimeric channels in astrocytes and suppression of TREK-1 surface expression by NHERF-1 increases KA-induced seizure susceptibility via reduction of astrocytic passive conductance.

Mycobacterium tuberculosis Antigen Rv1471 Induces Innate Immune Memory and Adaptive Immunity against Infection.

Protein subunit vaccines form a key pipeline for developing novel tuberculosis (TB) vaccines. Mycobacterium tuberculosis (Mtb) contains approximately 4000 individual proteins. However, only approximately 100 have been evaluated as antigens in the clinical and preclinical stages of vaccine development. Trained immunity-targeting vaccines induce innate immune memory against heterologous infections and enhance antigen-specific adaptive immune responses. However, no trained immunity-targeting subunit TB vaccine has been reported yet. This study tested Rv1471, a thioredoxin secreted by Mtb, as a candidate TB vaccine antigen due to its capacity to stimulate mouse bone marrow-derived macrophages (BMDMs). Rv1471 induced functional and phenotypic maturation of BMDMs in vitro, reflected by the increased production of inflammatory cytokines and surface expression of co-stimulatory molecules. Transcription analysis of Rv1471-trained BMDMs indicated that innate immune memory was activated through pathways of Akt-mTOR-HIF-1α and aerobic glycolysis. Rv1471 also enhanced innate immune memory responses and protection against intracellular infections of different mycobacteria. In a murine model of TB, immunization with Rv1471 formulated with liposomal DDA/MPLA adjuvant produced robust antigen-specific multi-functional CD4+ and CD8+ T-cell immune responses and had substantial protective efficacy against Mtb challenge. Analysis of recall immunity showed that the Rv1471 subunit vaccine triggered robust T-cell immunity post Mtb infection. These findings support the development of an innate immune memory-targeting subunit TB vaccine to increase TB vaccine efficacy.

Cytokine profile, differential somatic cell count, and oxidative status of Italian Mediterranean buffalo milk affected by the temperature–humidity index

In the context of climate change, there has been an increased interest in improving management practices for animals genetically adapted to extreme environmental conditions, such as buffaloes. The temperature–humidity index (THI) is used to determine the severity of heat stress in livestock. This study aimed to evaluate the cytokine profile, oxidative staus, differential somatic cell count (DCC), and the surface expression and activity of myeloperoxidase (MPO) in the somatic cells (SCs) of buffalo. Milk samples (n = 216) were collected from the spring to summer season under three different THI classes (THI < 72; ≤72 THI < 76, and THI ≥ 76). The cytokine profile was determined using ELISA, and the expression of DSCC and MPO was determined by flow cytometry. MPO activity was performed on SC extracts using a specific ELISA kit. Oxidative status was determined by the antioxidant/oxidant balance combining the free radical scavenging activity levels, and reactive oxygen and nitrogenous species. The results on the cytokine profile showed that at the THI ≥ 76 the levels of both IL-10 and IFN-γ were highest. IL-1β secretion was lower at the THI < 72 than at the THI values ranging from ≤72 THI < 76. Higher levels of both TNF-α and IL-12 were registered in both THI < 72 and THI ≥ 76 classes. The level of IL-4 was higher in the THI ≥ 76 class than in the ≤72 to <76 range. Data on DCC showed a decrease in the percentage of macrophages and lymphocytes as the THI increased from the ≤72 to <76 range to THI ≥ 76. Furthermore, the highest percentage of polymorphonuclear leukocyte (PMNLs) was registered in both ≤72 to <76 and THI ≥ 76 classes. The MPO activity and surface expression on SC were lower at a THI above 76, which could be associated with an absence of inflammation. A condition of oxidative imbalance was registered as demonstrated by the lower levels of antioxidant/oxidant balance along with increasing THI. Present data demonstrated that buffaloes were able to modulate the alteration of immune response activated by heat stress throughout a series of cross-linked mechanisms involving cytokine networks, different somatic cell distribution, and oxidative status.

Abstract B042: Molecular assessment of cell surface targets using integrated circulating tumor cell (CTC) RNAseq and single CTC phenotyping

Abstract Background: Androgen-targeted therapies are a mainstay of treatment for metastatic prostate cancer and have significantly improved patient outcomes. However, development of treatment resistance remains universal, occurring through androgen receptor (AR) alterations driving constitutive AR signaling, or lineage state transitions that bypass AR entirely and culminate in a small cell/neuroendocrine phenotype (NEPC). Cell surface targeted therapies, including antibody drug conjugates and targeted radioligand therapies, represent a new therapeutic class that has shown promise for treatment of androgen-resistant metastatic prostate cancer (mCRPC). Circulating tumor cells (CTCs) present an accessible source of tumor material to identify expression of known and novel targets for therapeutic development, as well as the unique potential for longitudinal profiling to understand the evolution of target expression and association with clinical resistance to cell surface targeted therapies. We have developed a CTC platform allowing for gene expression and protein profiling of cell surface targets on CTCs. Methods: Live CTCs were isolated with our automated microfluidic technology integrating negative and positive selection for CTC enrichment with a cohort of 273 samples. CTCs were captured immunomagnetically followed by RNA isolation on chip and RNA-seq, or protein staining on chip for single cell fluorescent quantification of prostate adenocarcinoma and NEPC cell surface targets including PSMA, TROP2, B7H3 and DLL3. Results: CTC RNA sequencing can be used to understand the expression of cell surface targets across different CTC phenotypes. In CTCs from patient with mCRPC, canonical prostate adenocarcinoma cell surface targets STEAP1, KLK2 and FOLH1 and epithelial cell surface target TACSTD2 had the highest expression, while prostate adenocarcinoma target STEAP2, pan-tumor target ERBB2, and tumor immune checkpoint cell surface protein CD276 (B7H3) had intermediate expression. Expression of DLL3 and SSTR2, targets associated with neuroendocrine differentiation, was lowest, though still detected in a subset of CRPC CTCs. Comparison of expression levels between CRPC and NEPC CTCs demonstrated lower expression of most adenocarcinoma cell surface targets in NEPC CTCs as expected, and a trend towards higher expression of DLL3 and SSTR2. Cell surface expression is being assessed for proteins including Trop-2, PSMA and DLL3. Evaluation of DLL3 at the protein level in a subset of patients including both CRPC (n=13) and NEPC (n=12) confirmed that DLL3 was detected in both adenocarcinoma and neuroendocrine CTCs, with a median of 45.8% DLL3-positive CTCs per sample. Conclusions: Biomarkers are needed to better predict response and resistance to targeted therapies. CTC RNAseq and single CTC phenotyping hold potential for predictive and on-treatment biomarkers of response to cell surface targeted therapies. Further study of mechanisms driving response and resistance can be evaluated with these biomarkers. Citation Format: Jamie M. Sperger, Marina N. Sharifi, Katherine R. Kaufmann, Matthew L. Bootsma, Shannon R. Reese, Viridiana Carreno, Alex H. Chang, Luke A. Nunamaker A. Nunamaker, Charlotte Linebarger, Amy K. Taylor, Katherine E Tippins, Kyle T. Helzer, Shuang G. Zhao, Joshua M Lang. Molecular assessment of cell surface targets using integrated circulating tumor cell (CTC) RNAseq and single CTC phenotyping [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr B042.

Exploring the sequence diversity and surface expression of Factor H-Binding Protein among invasive serogroup B meningococcal strains from selected European countries

ABSTRACT Factor H-Binding Protein (fHbp) is a key component of meningococcal vaccines such as MenB-fHbp, licensed in the EU, UK, and other countries. Sufficient expression of fHbp on the bacterial surface is necessary for vaccine-induced antibodies to bind and exert bactericidal activity. The flow cytometric MEASURE assay quantifies fHbp expression in vitro, and previous studies have shown that strains with a Mean Fluorescence Intensity (MFI) >1000 are likely to be killed by MenB-fHbp-induced antibodies. This study assessed fHbp peptide distribution and expression among 451 invasive group B strains collected in 2016 across England, Wales, and Northern Ireland (EW&NI), Germany, Italy, and Spain. We found that 92% of the strains expressed fHbp above the MFI 1000 threshold. The strain distribution across EW&NI, Germany, and Italy was similar, with coverage ranging from 92.1% to 94.6%, dominated by a small number of clonal complexes and fHbp peptides. Although, the Spanish subset had a higher proportion of lower-expressing strains, particularly clonal complex 213, resulting in a lower predicted coverage for Spain (84%). These results, along with other published MEASURE data, can provide a basis for genotypic MenB-fHbp coverage predictions, however, inclusion of the upstream intergenic sequence of the fHbp gene in the prediction improved its accuracy by distinguishing between low- and high-expressing strains. Future MEASURE analyses of strains with less common fHbp variants would serve to further refine vaccine coverage predictions.

EXTH-66. ONCOLYTIC ADENOVIRAL INFECTION SYNERGIZES WITH IMMUNE CHECKPOINT INHIBITION TO MEDIATE INTRACRANIAL TUMOR CONTROL IN DISPARATE MODELS OF MELANOMA BRAIN METASTASES

Abstract Amongst all solid cancers, melanoma brain metastases (MBM) have the highest likelihood of metastasizing to the brain. The emergence of immune checkpoint inhibitors (ICI) for metastatic melanoma have demonstrated increasingly promising results; however, intracranial progression remains a challenging obstacle. Oncolytic viral (OV) therapy leverages tumor cell replication machinery to selectively replicate and kill tumor cells and promote anti-tumor immunity. We propose this OV strategy can be applied to MBM through direct tumor infection that simultaneously sustains a distant antitumor immune response. To counteract immunosuppressive features of the tumor microenvironment (TME), a third-generation oncolytic adenovirus (Delta-24-RGDOX) has been developed which expresses the immune stimulatory OX40 ligand (OX40L). We quantified the cytotoxic capacity of Delta-24-RGDOX and its ability to achieve immunogenic cell death (ICD) in vitro along with cerebral organoid co-culture models. Additionally, we used a series of syngeneic murine melanoma models to explore local and systemic antitumor immunity following Delta-24-RGDOX infection. Delta-24-RGDOX inoculation achieved viral infection, OX40L cell surface expression, tumor cell cytotoxicity, and ICD in vitro. Viral oncolysis was recapitulated in a cerebral organoid melanoma co-culture model with concomitant alterations in microglia activation and detection of viral transcripts within microglia using single cell RNA sequencing, suggesting a viral-clearing role of microglia within the TME. Local tumor clearance was achieved in orthotopic intracranial models following direct intracranial viral inoculation alone, and in combination with ICI. Lastly, we demonstrated improvement in overall survival in a synchronous subcutaneous/intracranial B16F10 model where the subcutaneous tumor was treated with Delta-24-RGDOX in combination with ICI. In summary, Delta-24-RGDOX achieves viral infection, oncolysis, and ICD following infection of melanoma cell lines. These findings translated in multiple in vivo models including immune cell activation and systemic antitumor immunity against uninfected MBM. Future studies are needed to explore the role of immune cell trafficking, myeloid cell modulation, T cell priming, and clonal expansion withing locally infected and the distant melanoma TME.

IMMU-01. DE NOVO-DESIGNED BINDER-BASED CAR T CELLS ENABLE EFFECTIVE TARGETING OF GLIOBLASTOMA

Abstract Glioblastoma is a devastating disease with poor responses to all current therapies. Chimeric antigen receptor (CAR) T cell therapy has achieved impressive success against hematological malignancies but produces responses in only a limited number of glioblastoma patients. Here, we developed a novel platform for CAR constructs using de novo designed protein binders to target tumor antigens. We firstly designed a binder CAR targeting epidermal growth factor receptor (EGFR), which is highly expressed in glioblastoma, to validate the feasibility of our platform. Our EGFR binder CAR design promoted CAR T cell proliferation, cytotoxic cytokine secretion and exhaustion resistance, leading to better antitumor performance both in vitro and in vivo. Bulk and single-cell transcriptional profiling of binder CAR T cells revealed an underlying mechanism involving enhanced effector activity and reduced exhaustion responses. Mechanismly, the binder CARs exhibited higher surface expression and greater resistance to degradation triggered by tumor antigens. Moreover, we designed and engineered a novel CD276 binder CAR T cell product and verified its antitumor function, further demonstrating the general applicability of our binder-based CAR platform. Overall, our study provides an alternative avenue for the design of a CAR antigen-binding domain to potentiate CAR T cell antitumor efficacy.

EXTH-24. THERAPEUTIC TARGETING OF MISLOCALIZED NUCLEAR ENVELOPE PROTEINS INMYC-DRIVEN GROUP 3 MEDULLOBLASTOMA

Abstract Medulloblastoma (MB) is the most common, malignant pediatric brain tumour comprised of four distinct molecular subgroups (WNT, SHH, Group 3, and Group 4). A subset of Group 3 MB tumors harbors focal amplifications of the MYC oncogene (MYC-G3MB) and are particularly prone to tumour recurrence due to their highly proliferative nature linked to its embryonic stem cell-of-origin and programming. We discovered that LBR, an inner nuclear transmembrane protein, while present in all cells at the nuclear envelope (NE), is aberrantly presented to the cell surface in MYC-G3MBs. Transcriptomic profiling of publicly available datasets identified significant NE protein enrichment in MYC-G3MB compared to normal tissue and high expression during fetal development that dampens postnatally and in adult samples. Immunohistochemistry analysis of LBR on patient tumors was able to significantly prognosticate overall and progression free survival. Flow cytometry analysis identified LBR cell surface expression in MYC-G3MBs with low to no expression in human neural stem cells and other MB subgroups. High resolution microscopy of endogenously tagged LBR revealed cell surface presentation to be linked to ER-like vesicles that directly trafficked to the cell surface in MYC-G3MBs. Transcriptomic analysis of LBR cell surface positive and negative cells identified LBR to be linked to mitotic processes and mislocalization was significantly enriched following exposure to chemotherapy and radiation in vitro and in vivo. Therefore, we demonstrate that LBR is an ideal therapeutic target for patients facing treatment-refractory MB and have generated single domain antibodies (sdAb) to develop LBR-CAR T cells. Validation of LBR sdAbs demonstrate on-target binding and comparable affinity and avidity to commercial LBR antibodies. There is an undeniable paucity of targets for MB patients stemming from the lack of neoantigens and genomic aberrations in pediatric tumors. The preclinical development and validation of novel immunotherapeutic targets such as LBR provides alternative therapies for patients otherwise facing palliation.

DDDR-39. PI3 KINASE AND CHECKPOINT INHIBITION: A POTENTIALLY NOVEL THERAPEUTIC STRATEGY FOR GLIOBLASTOMA (GBM)

Abstract Glioblastoma is the most common and aggressive malignant brain tumor with a median survival of less than 2 years, highlighting the need for more effective therapeutics. Dual pathway synergism between PI3K inhibitors and check-point inhibitors is a promising therapeutic avenue that has not been explored. Based on this possibility, we hypothesized that the combination of PI3K and checkpoint inhibitors will improve survival in our native glioblastoma mouse model. Treatment with GCT-007, a small molecule PI3K inhibitor, induces growth arrest of GBM cells that is accompanied by increases in the cell surface expression of molecules targeted by the immune system and immunotherapy drugs, including MHC Class II and PD-L1. Treatment of mouse GL261 and human U251 GBM cell lines with GCT-007 caused growth arrest, increased the cell surface expression of PD-L1 and MHC class II, and synergized with radiation to cause growth arrest and cell death. We compared GCT-007 to Paxalisib in our in vitro studies and observed that GCT-007 outperformed Paxalisib at increasing MHC class II and PD-L1 expression on the tumor cells at equivalent doses. We then performed in vivo animal studies using our native mouse GBM model. We treated mice orally with GCT-007 and observed a significantly prolonged survival compared to placebo. Mice treated with anti-PD1 resulted in a sexually dimorphic response consisting of prolonged remission of all female mice, now surviving beyond 1 year, but no improvement in the survival of male mice compared to placebo. Adding GCT-007 to anti-PD1 did not alter the prolonged remission outcome in female mice, it did result in prolonged remission of 25% of the male mice, now beyond 1 year. In conclusion, these results indicate that GCT-007 treatment alone improves survival in our native GBM mouse model and it may also improve the response to immune checkpoint inhibitor therapy in at least a fraction of GBM tumors. These data warrant further investigation as a potentially novel therapeutic approach to GBM.

Examination of respiratory syncytial virus fusion protein proteolytic processing and roles of the P27 domain.

The respiratory syncytial virus (RSV) fusion protein (F) facilitates virus-cell membrane fusion, which is critical for viral entry, and cell-cell fusion. In contrast to many type I fusion proteins, RSV F must be proteolytically cleaved at two distinct sites to be fusogenic. Cleavage at both sites results in the release of a 27 amino-acid fragment, termed Pep27. We examined proteolytic processing and the role of Pep27 for RSV F from both RSV A2 and RSV B9320 laboratory-adapted strains, allowing important comparisons between A and B clade F proteins. F from both clades was cleaved at both sites, and pulse-chase analysis indicated that cleavage at both sites occurs early after synthesis, most likely within the secretory pathway. Mutation of either site to alter the furin recognition motif blocked cell-cell fusion activity. To assess the role of Pep27 in F processing and expression, we deleted the Pep27 fragment, but preserved the cleavage sites. Deletion of Pep27 reduced F surface expression and cell-cell fusion. Two conserved N-linked glycosylation sites within Pep 27 are present in both the RSV A2 and RSV B9320 F. Randomization of the Pep27 sequence, while conserving the two N-liked glycosylation sites, did not significantly change surface expression, and only modestly reduced cell-cell fusion. However, the disruption of either Pep27 glycosylation site reduced cell-cell fusion. This work clarifies the timing of RSV F proteolytic cleavage and offers insight into the crucial role the N-linked glycosylation sites within Pep27 play in the biological function of F.

New insights into the immunomodulatory potential of sialic acid on monocyte-derived dendritic cells

Sialic acids at the cell surface of dendritic cells (DCs) play an important immunomodulatory role, and their manipulation enhances DC maturation, leading to heightened T cell activation. Particularly, at the molecular level, the increased stability of surface MHC-I molecules in monocyte-derived DCs (MoDCs) underpins an improved DC: T cell interaction. In this study, we focused on the impact of sialic acid remodelling by treatment with Clostridium perfringens sialidase on MoDCs' phenotypic and functional characteristics. Our investigation juxtaposes this novel approach with the conventional cytokine-based maturation regimen commonly employed in clinical settings.Notably, C. perfringens sialidase remarkably increased MHC-I levels compared to other sialidases having different specificities, supporting the idea that higher MHC-I is due to the cleavage of specific sialoglycans on cell surface proteins. Sialidase treatment induced rapid elevated surface expression of MHC-I, MHC-II and CD40 within an hour, a response not fully replicated by 48 h cytokine cocktail treatment. These increases were also observable 48 h post sialidase treatment. While CD86 and PD-L1 showed significant increases after 48 h of cytokine maturation, 48 h post sialidase treatment showed a higher increase in CD86 and shorter increase in PD-L1. CCR-7 expression was significantly increased 48 h after sialidase treatment but not significantly affected by cytokine maturation. Both treatments promoted higher secretion of the IL-12 cytokine. However, the cytokine cocktail induced a more pronounced IL-12 production. SNA lectin staining analysis demonstrated that the sialic acid profile is significantly altered by sialidase treatment, but not by the cytokine cocktail, which causes only slight sialic acid upregulation. Notably, the lipid-presenting molecules CD1a, CD1b and CD1c remained unaffected by sialidase treatment in MoDCs, a finding also further supported by experiments performed on C1R cells. Inhibition of endogenous sialidases Neu1 and Neu3 during MoDC differentiation did not affect surface MHC-I expression and cytokine secretion. Yet, sialidase activity in MoDCs was minimal, suggesting that sialidase inhibition does not significantly alter MHC-I-related functions. Our study highlights the unique maturation profile induced by sialic acid manipulation in MoDCs. These findings provide insights into the potential of sialic acid manipulation as a rapid immunomodulatory strategy, offering promising avenues for targeted interventions in inflammatory contexts.

Ras-related Protein in Brain 4A (Rab4A) is Downregulated by miR-496 to inhibit the Progression of Gastric Cancer.

Ras-related protein in brain 4A (Rab4A), as a member of the Rab family, is involved in the intracellular circulation of membrane receptors or endocytic substances and regulates the progression of multiple tumors. From our results, the knockdown of Rab4A inhibited the proliferation, migration and invasion in AGS cells. Importantly, the surface expression of epidermal growth factor receptor (EGFR) declined significantly in Rab4A knockdown cells. The downstream pathway of EGFR was also inhibited after the transfection of Rab4A-specific siRNA, including AKT and β-catenin pathways. In addition, miR-496 down-regulated the expression of Rab4A in AGS cells. The result of the luciferase reporter assay showed that miR-496 could bind to the 3'UTR of Rab4A. In conclusion, the expression of Rab4A is inhibited by miR-496, and the knockdown of Rab4A inhibits the proliferation, migration and invasion through down-regulating the surface expression of EGFR. Rab4A is a potential target in the treatment of gastric cancer.

Mapping hydrothermal alteration in regolith using white micas and chlorite as vectors towards gold mineralization

Mineral exploration through regolith-dominated terrains poses a significant challenge to cost-effective exploration techniques. Due to missing surface expression, undercover mineral exploration relies on understanding ore-forming processes and characterizing alteration regimes to decipher suitable vectors towards ore deposits. The work presented focuses on the Archean granite-greenstones of the Yilgarn Craton, east of the Meekatharra area in Western Australia, and characterizes the weathering profiles by understanding metal dispersion mechanisms and identifying mineralogical vectors towards gold mineralization within regolith. Mineral mapping of gold mineralization using TESCAN Integrated Mineral Analyzer and laser ablation ICP-MS shows gold is associated with multiple generations of pyrite, and base metal sulfides and sulfosalts hosted in felsic to intermediate volcanics and volcaniclastics. Intensive weathering generated a thick regolith profile dominated by a leached zone of kaolinitic and micaceous saprolite underlain by a supergene Au-Cu deposit blanket at the base. The supergene deposit is dominated by colloform and framboidal pyrite, with pure microcrystalline Au, chalcocite, bornite, malachite, and alunite. Hyperspectral analyses were used to trace the composition and abundance of chlorite and white mica variations in the host rock and the weathering profile. The mineral assemblage in the hydrothermal alteration halo proximal to and intersecting gold mineralization is dominated by Fe-rich chlorite and Na-rich white mica (paragonite). Fe-rich chlorite and paragonite are spatially tied to elevated Au concentration and trends to Fe-Mg-rich chlorite and K-rich white mica (muscovite) distal to the alteration. The variations in chlorite chemistry were detected mainly in bedrock and saprock. Conversely, the white mica chemistry variations were detected in bedrock and the regolith profile, in which white micas resist intensive weathering. The spectral signatures identified through short-wave and thermal infrared data are verified through X-ray diffraction, mineral chemistry, and bulk geochemical analyses. This distinctive spectral signature of white mica and chlorite is a cost-effective exploration method for regional mapping of mineral systems to identify hydrothermal alteration footprints in the regolith developed over felsic and intermediate rocks.

Subcellular expression of CD30 in cutaneous mastocytosis-An important factor for targeted treatment.

The subcellular distribution of CD30 on mast cells and the presence of eosinophils in cutaneous mastocytosis require further investigation, especially as the cell surface expression of CD30 is critical for the therapeutic response of systemic mastocytosis to brentuximab vedotin. Investigation of 147 biopsy specimens from 143 patients with cutaneous mastocytosis for mast cell density and distribution, frequency of CD30 expression, CD30 staining patterns, and presence and distribution of eosinophils. Correlation with clinical patterns. Retrospective multicenter immunohistochemical study of CD30 expression, eosinophils and basic clinical data in cutaneous mastocytosis. CD30 expression was found in all samples (cut-off: ≥1%), whereby the staining was predominantly cytoplasmic in 99% of the samples. Additional membrane staining was detected in 62% of the samples. Surface expression of CD30 was more common in biopsy specimens with a high mast cell burden and in biopsy specimens with a higher CD30 expression rate. Eosinophils were admixed in 58% of the samples. Females and older patients showed a trend of a lower mast cell burden. Retrospective study on formalin-fixed and paraffin-embedded tissue without functional analysis. Most cases of cutaneous mastocytosis show cell surface expression of CD30 expression and is, therefore, in principle, accessible for therapy with antibodies against CD30, provided the overall situation of the patient warrants.

O-glycosylation is essential for cell surface expression of the transcobalamin receptor CD320

O-glycosylation is essential for cell surface expression of the transcobalamin receptor CD320

Planetary Interior Configuration Control on Thermal Evolution and Geological History

AbstractThe terrestrial planetary bodies display a wide variety of surface expressions and histories of volcanic and tectonic, and magnetic activity, even those planets with apparently similar dominant modes of heat transport (e.g., conductive on Mercury, the Moon, and Mars). Each body also experienced differentiation in its earliest evolution, which may have led to density‐stabilized layering in its mantle and a heterogenous distribution of heat‐producing elements (HPE). We explore the hypothesis that mantle structure exerts an important control on the occurrence and timing of geological processes such as volcanism and tectonism. We numerically investigate the behavior of an idealized model of a planetary body where HPE are assumed to be sequestered in a stabilized layer at the top or bottom of the mantle. We find that the mantle structure alters the patterns of heat flow at the boundaries of major heat reservoirs: The mantle and core. This modulates the way in which heat production influences geological processes. In the model, the mantle structure is a dominant control on the relative timing of fundamental processes such as volcanism, magnetic field generation, and expansion/contraction, the record of which may be observable on planetary body surfaces. We suggest that Mercury exhibits characteristics of shallow sequestration of HPE and that Mars exhibits characteristics of deep sequestration.

Fasudil Alleviates Postoperative Neurocognitive Disorders in Mice by Downregulating the Surface Expression of α5GABAAR in Hippocampus.

Postoperative neurocognitive disorder (PND) refers to the cognitive impairment experienced by patients after surgery. As a target of sevoflurane, a kind of inhalation anesthetic, the balance of the GABAergic system can be disrupted during the perioperative period. In this study, we explored the promoting effect of abnormal elevation of the α5 subtype of γ-aminobutyric acid type A (GABAA) receptors caused by sevoflurane and surgical trauma on PND, as well as the therapeutic effect of fasudil on PND. Eight-week-old mice were pretreated with fasudil, and after 10 days, sevoflurane-induced femoral fracture surgery was performed to establish an animal model of PND. The Morris water maze and fear conditioning tests were used to evaluate PND induced by this model. Biochemical and electrophysiological analyses were conducted to assess the protective effect of fasudil on the GABAergic system. Following artificial fracture, the hippocampus-dependent memory was damaged in these mice. Fasudil pretreatment, however, ameliorated cognitive function impairment in mice induced by sevoflurane and surgery. Mechanistically, fasudil was found to restore the increased hippocampus expression and function of α5GABAARs in mice with PND. In addition, pretreatment with Fasudil inhibited the enhancement in the calcium ion concentration and phosphorylation of Camk2, as well as the activation of the Radixin pathway which led to increased phosphorylation of the ERM family in the hippocampal CA1 region of the PND model. Preadministration of fasudil improved postoperative cognitive function in PND mice by inhibiting the activation of Camk2 and Radixin pathways and finally downregulating the surface expression of α5GABAAR in hippocampus neurons.