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1.
Cells ; 12(21)2023 10 31.
Article in English | MEDLINE | ID: mdl-37947636

ABSTRACT

T cells can express multiple inhibitory receptors. Upon induction of T cell exhaustion in response to a persistent antigen, prominently in the anti-tumor immune response, many are expressed simultaneously. Key inhibitory receptors are CTLA-4, PD-1, LAG3, TIM3, and TIGIT, as investigated here. These receptors are important as central therapeutic targets in cancer immunotherapy. Inhibitory receptors are not constitutively expressed on the cell surface, but substantial fractions reside in intracellular vesicular structures. It remains unresolved to which extent the subcellular localization of different inhibitory receptors is distinct. Using quantitative imaging of subcellular distributions and plasma membrane insertion as complemented by proximity proteomics and biochemical analysis of the association of the inhibitory receptors with trafficking adaptors, the subcellular distributions of the five inhibitory receptors were discrete. The distribution of CTLA-4 was most distinct, with preferential association with lysosomal-derived vesicles and the sorting nexin 1/2/5/6 transport machinery. With a lack of evidence for the existence of specific vesicle subtypes to explain divergent inhibitory receptor distributions, we suggest that such distributions are driven by divergent trafficking through an overlapping joint set of vesicular structures. This extensive characterization of the subcellular localization of five inhibitory receptors in relation to each other lays the foundation for the molecular investigation of their trafficking and its therapeutic exploitation.


Subject(s)
Neoplasms , T-Lymphocytes , Mice , Animals , CTLA-4 Antigen/metabolism , Carrier Proteins/metabolism , Neoplasms/metabolism , Immunotherapy
2.
bioRxiv ; 2023 Jul 25.
Article in English | MEDLINE | ID: mdl-37503045

ABSTRACT

T cells can express multiple inhibitory receptors. Upon induction of T cell exhaustion in response to persistent antigen, prominently in the anti-tumor immune response, many are expressed simultaneously. Key inhibitory receptors are CTLA-4, PD-1, LAG3, TIM3 and TIGIT, as investigated here. These receptors are important as central therapeutic targets in cancer immunotherapy. Inhibitory receptors are not constitutively expressed on the cell surface, but substantial fractions reside in intracellular vesicular structures. It remains unresolved to which extent the subcellular localization of different inhibitory receptors is distinct. Using quantitative imaging of subcellular distributions and plasma membrane insertion as complemented by proximity proteomics and a biochemical analysis of the association of the inhibitory receptors with trafficking adaptors, the subcellular distributions of the five inhibitory receptors were discrete. The distribution of CTLA-4 was most distinct with preferential association with lysosomal-derived vesicles and the sorting nexin 1/2/5/6 transport machinery. With a lack of evidence for the existence of specific vesicle subtypes to explain divergent inhibitory receptor distributions, we suggest that such distributions are driven by divergent trafficking through an overlapping joint set of vesicular structures. This extensive characterization of the subcellular localization of five inhibitory receptors in relation to each other lays the foundation for the molecular investigation of their trafficking and its therapeutic exploitation.

3.
Pneumonia (Nathan) ; 15(1): 11, 2023 Jul 25.
Article in English | MEDLINE | ID: mdl-37488633

ABSTRACT

OBJECTIVE: To assess the safety and utility of a pragmatic clinical algorithm to guide rational antibiotic use in children presenting with respiratory infection. METHODS: The effect of an algorithm to guide the management of young (< 5 years) children presenting with respiratory symptoms to the Da Nang Hospital for Women and Children, Vietnam, was evaluated in a before-after intervention analysis. The main outcome was reduction in antibiotic use, with monitoring of potential harm resulting from reduced antibiotic use. The intervention comprised a single training session of physicians in the use of an algorithm informed by local evidence; developed during a previous prospective observational study. The evaluation was performed one month after the training. RESULTS: Of the 1290 children evaluated before the intervention, 102 (7.9%) were admitted to hospital and 556/1188 (46.8%) were sent home with antibiotics. Due to COVID-19, only 166 children were evaluated after the intervention of whom 14 (8.4%) were admitted to hospital and 54/152 (35.5%) were sent home with antibiotics. Antibiotic use was reduced (from 46.8% to 35.5%; p = 0.009) after clinician training, but adequate comparison was compromised. The reduction was most pronounced in children with wheeze or runny nose and no fever, or a normal chest radiograph, where antibiotic use declined from 46.7% to 28.8% (p < 0.0001). The frequency of repeat presentation to hospital was similar between the two study periods (141/1188; 11.9% before and 10/152; 6.6% after; p = 0.10). No child represented with serious disease after being sent home without antibiotics. CONCLUSIONS: We observed a reduction in antibiotic use in young children with a respiratory infection after physician training in the use of a simple evidence-based management algorithm. However, the study was severely impacted by COVID-19 restrictions, requiring further evaluation to confirm the observed effect.

4.
Front Immunol ; 13: 908305, 2022.
Article in English | MEDLINE | ID: mdl-35693787

ABSTRACT

The major histocompatibility complex (MHC) is crucial for appropriate immune responses against invading pathogens. Chickens possess a single predominantly-expressed class I molecule with strong associations between disease resistance and MHC haplotype. For Marek's disease virus (MDV) infections of chickens, the MHC haplotype is one of the major determinants of genetic resistance and susceptibility. VALO specific pathogen free (SPF) chickens are widely used in biomedical research and vaccine production. While valuable findings originate from MDV infections of VALO SPF chickens, their MHC haplotypes and associated disease resistance remained elusive. In this study, we used several typing systems to show that VALO SPF chickens possess MHC haplotypes that include B9, B9:02, B15, B19 and B21 at various frequencies. Moreover, we associate the MHC haplotypes to MDV-induced disease and lymphoma formation and found that B15 homozygotes had the lowest tumor incidence while B21 homozygotes had the lowest number of organs with tumors. Finally, we found transmission at variable levels to all contact birds except B15/B21 heterozygotes. These data have immediate implications for the use of VALO SPF chickens and eggs in the life sciences and add another piece to the puzzle of the chicken MHC complex and its role in infections with this oncogenic herpesvirus.


Subject(s)
Herpesvirus 2, Gallid , Marek Disease , Animals , Carcinogenesis/genetics , Chickens/genetics , Disease Resistance/genetics , Haplotypes , Herpesvirus 2, Gallid/genetics , Histocompatibility Antigens , Major Histocompatibility Complex/genetics
5.
Clin Breast Cancer ; 22(4): e457-e462, 2022 06.
Article in English | MEDLINE | ID: mdl-34920954

ABSTRACT

INTRODUCTION: Diagnosis of LM is limited by low sensitivity of cerebrospinal fluid (CSF) cytopathology. Detecting tumor cells in CSF (CSF-TCs) might be more sensitive. We evaluated if CNSide (CNSide), a novel assay for tumor cell detection in CSF, can detect CSF-TCs better than conventional CSF cytology. METHODS: We enrolled adults with metastatic breast cancer and clinical suspicion for LM to undergo lumbar puncture (LP) for CSF cytopathology and CNSide. CNSide captured CSF-TCs using a primary 10-antibody mixture, streptavidin-coated microfluidic channel, and biotinylated secondary antibodies. CSF-TCs were assessed for estrogen receptor (ER) expression by fluorescent antibody and HER2 amplification by fluorescent in situ hybridization (FISH). CSF cell-free DNA (cfDNA) was extracted for next-generation sequencing (NGS). Leptomeningeal disease was defined as positive CSF cytology and/or unequivocal MRI findings. We calculated sensitivity and specificity of CSF cytology and CNSide for the diagnosis of LM. RESULTS: Ten patients, median age 51 years (range, 37-64), underwent diagnostic LP with CSF evaluation by cytology and CNSide. CNSide had sensitivity of 100% (95% Confidence Interval [CI], 40%-100%) and specificity of 83% (95% CI, 36%-100%) for LM. Among these patients, concordance of ER and HER2 status between CSF-TCs and metastatic biopsy were 60% and 75%, respectively. NGS of CSF cfDNA identified somatic mutations in three patients, including one with PIK3CA p.H1047L in blood and CSF. CONCLUSIONS: CNSide may be a viable platform to detect CSF-TCs, with potential use as a diagnostic tool for LM in patients with metastatic breast cancer. Additional, larger studies are warranted.


Subject(s)
Breast Neoplasms , Cell-Free Nucleic Acids , Meningeal Carcinomatosis , Biomarkers, Tumor , Breast Neoplasms/diagnosis , Breast Neoplasms/genetics , Female , Humans , In Situ Hybridization, Fluorescence , Meningeal Carcinomatosis/secondary
6.
BMC Health Serv Res ; 17(1): 719, 2017 Nov 13.
Article in English | MEDLINE | ID: mdl-29132355

ABSTRACT

BACKGROUND: With the decline in funding for Viet Nam's response to the HIV epidemic, there is a need for evidence on the criteria to guide the prioritization of HIV programs. There is a gap in the research on the relative importance of multiple criteria for prioritizing a package of interventions. This study elicits preferences and the trade-offs made between different HIV programs by relevant stakeholders and decision-makers in Viet Nam. It also pays attention to how differences in social and professional characteristics of stakeholders and their agency affiliations shape preferences for HIV program criteria in Viet Nam. METHODS: This study uses self-explicated ranking and discrete choice experiments to determine the relative importance of five criteria - effectiveness, feasibility, cost-effectiveness, rate of investment and prevention/treatment investment ratio - to stakeholders when they evaluate and select hypothetical HIV programs. The study includes 69 participants from government, civil society, and international development partners. RESULTS: Results of the discrete choice experiment show that overall the feasibility criterion is ranked highest in importance to the participants when choosing a hypothetical HIV program, followed by sustainability, treatment to prevention spending ratio, and effectiveness. The participant's work in management, programming, or decision-making has a significant effect on the importance of some criteria to the participant. In the self-explicated ranking effectiveness is the most important criterion and the cost-effectiveness criterion ranks low in importance across all groups. CONCLUSIONS: This study has shown that the preferred HIV program in Viet Nam is feasible, front-loaded for sustainability, has a higher proportion of investment on prevention, saves more lives and prevents more infections. Similarities in government and civil society rankings of criteria can create common grounds for future policy dialogues between stakeholders. Innovative models of planning should be utilized to allow inputs of informed stakeholders at relevant stages of the HIV program planning process.


Subject(s)
HIV Infections/prevention & control , Health Priorities/standards , Health Services Accessibility , Policy Making , Adult , Choice Behavior , Female , HIV Infections/epidemiology , Humans , Male , Middle Aged , Pilot Projects , Program Evaluation , Stakeholder Participation , Vietnam/epidemiology
7.
Br J Nutr ; 110(3): 420-5, 2013 Aug 28.
Article in English | MEDLINE | ID: mdl-23312069

ABSTRACT

The present single-dose study was performed to assess the effect of whole coffee fruit concentrate powder (WCFC), green coffee caffeine powder (N677), grape seed extract powder (N31) and green coffee bean extract powder (N625) on blood levels of brain-derived neurotrophic factor (BDNF). Randomly assorted groups of fasted subjects consumed a single, 100mg dose of each material. Plasma samples were collected at time zero (T0) and at 30 min intervals afterwards, up to 120 min. A total of two control groups were included: subjects treated with silica dioxide (as placebo) or with no treatment. The collected data revealed that treatments with N31 and N677 increased levels of plasma BDNF by about 31% under these experimental conditions, whereas treatment with WCFC increased it by 143% (n 10), compared with baseline. These results indicate that WCFC could be used for modulation of BDNF-dependent health conditions. However, larger clinical studies are needed to support this possibility.


Subject(s)
Brain-Derived Neurotrophic Factor/blood , Coffea/chemistry , Fruit/chemistry , Plant Extracts/pharmacology , Caffeine/pharmacology , Humans , Seeds , Silicon Dioxide , Vitis
8.
J Am Chem Soc ; 134(13): 5762-5, 2012 Apr 04.
Article in English | MEDLINE | ID: mdl-22443098

ABSTRACT

The first single-source molecular precursor for a lithium-manganese cathode material is reported. Heterometallic ß-diketonate LiMn(2)(thd)(5) (1, thd = 2,2,6,6-tetramethyl-3,5-heptanedionate) was obtained in high yield by simple one-step solid-state reactions employing commercially available reagents. Substantial scale-up preparation of 1 was achieved using a solution approach. The crystal structure of the precursor contains discrete Li:Mn = 1:2 trinuclear molecules held together by bridging diketonate ligands. The complex is relatively stable in open air, highly volatile, and soluble in all common solvents. It was confirmed to retain its heterometallic structure in solutions of non-coordinating solvents. The heterometallic diketonate 1 was shown to exhibit clean, low-temperature decomposition in air/oxygen that results in nanosized particles of spinel-type oxide LiMn(2)O(4), one of the leading cathode materials for lithium ion batteries.

9.
Inorg Chem ; 48(13): 6152-8, 2009 Jul 06.
Article in English | MEDLINE | ID: mdl-19499893

ABSTRACT

The heterometallic complex [Bi(2)Pd(2)(O(2)CCF(3))(10)(HO(2)CCF(3))(2)] (1) was obtained by the solid state reaction of Bi(III) trifluoroacetate/trifluoroacetic acid adduct with unsolvated trinuclear Pd(II) trifluoroacetate. The crystal structure of 1 consists of discrete tetranuclear molecules, in which two paddlewheel [BiPd(O(2)CCF(3))(4)] units are connected by two chelating-bridging trifluoroacetate ligands through bismuth ends. There are no metal-metal bonds in the tetrameric structure of 1, since both Bi...Pd (3.0843(4) A) and Bi...Bi (4.5074(4) A) distances are too long to be considered as bonding interactions. A study of the solution behavior revealed that not only the coordinated trifluoroacetic acid in 1 can be effectively replaced by other donor solvent molecules but also the tetranuclear complex can be cleaved in solution into discrete dinuclear Bi-Pd species. Complex 1 was used as precursor for the preparation of a bimetallic Pd-Bi carbon-supported catalyst. The preparation procedure included the modification of the carbon support to increase the number of oxygenated functions at its surface followed by grafting complex 1 via ligand exchange for surface carboxylates and activating thermally. The resulting catalyst, consisting of small supported metallic particles, was found to be more active than the reference materials prepared from multisource homometallic Pd and Bi precursors.

10.
Inorg Chem ; 46(22): 9155-9, 2007 Oct 29.
Article in English | MEDLINE | ID: mdl-17900182

ABSTRACT

Mixed-metal molybdenum(II)/rhodium(II) tetra(trifluoroacetate) of the composition [(MoRh)(O2CCF3)4] has been obtained from the gas-phase reaction between volatile carboxylates, [Mo2(O2CCF3)4] and [Rh2(O2CCF3)4]. This is an interesting system for which a single-crystal X-ray investigation fails to provide an unambiguous evidence of whether the product consists of the initial homometallic or newly formed heterometallic paddlewheel units. In the solid-state structure both metal atoms occupy the same crystallographic position, while the M-M and M-O distances are averaged with respect to the parent homometallic compounds. Nevertheless, the results of mass-spectrometric and magnetic measurements clearly indicate that the title bimetallic carboxylate contains a statistical mixture of homometallic dimolybdenum and dirhodium units. The product can be considered as a result of cocrystallization of isomorphous paddlewheel molecules.

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