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1.
Front Immunol ; 15: 1328602, 2024.
Article in English | MEDLINE | ID: mdl-38361951

ABSTRACT

Introduction: Quantitative, multiplexed imaging is revealing complex spatial relationships between phenotypically diverse tumor infiltrating leukocyte populations and their prognostic implications. The underlying mechanisms and tissue structures that determine leukocyte distribution within and around tumor nests, however, remain poorly understood. While presumed players in metastatic dissemination, new preclinical data demonstrates that blood and lymphatic vessels (lymphovasculature) also dictate leukocyte trafficking within tumor microenvironments and thereby impact anti-tumor immunity. Here we interrogate these relationships in primary human cutaneous melanoma. Methods: We established a quantitative, multiplexed imaging platform to simultaneously detect immune infiltrates and tumor-associated vessels in formalin-fixed paraffin embedded patient samples. We performed a discovery, retrospective analysis of 28 treatment-naïve, primary cutaneous melanomas. Results: Here we find that the lymphvasculature and immune infiltrate is heterogenous across patients in treatment naïve, primary melanoma. We categorized five lymphovascular subtypes that differ by functionality and morphology and mapped their localization in and around primary tumors. Interestingly, the localization of specific vessel subtypes, but not overall vessel density, significantly associated with the presence of lymphoid aggregates, regional progression, and intratumoral T cell infiltrates. Discussion: We describe a quantitative platform to enable simultaneous lymphovascular and immune infiltrate analysis and map their spatial relationships in primary melanoma. Our data indicate that tumor-associated vessels exist in different states and that their localization may determine potential for metastasis or immune infiltration. This platform will support future efforts to map tumor-associated lymphovascular evolution across stage, assess its prognostic value, and stratify patients for adjuvant therapy.


Subject(s)
Lymphatic Vessels , Melanoma , Skin Neoplasms , Humans , Retrospective Studies , Immunohistochemistry , Lymphatic Vessels/pathology , Tumor Microenvironment
3.
Nat Immunol ; 24(4): 664-675, 2023 04.
Article in English | MEDLINE | ID: mdl-36849745

ABSTRACT

Antigen-specific CD8+ T cell accumulation in tumors is a prerequisite for effective immunotherapy, and yet the mechanisms of lymphocyte transit are not well defined. Here we show that tumor-associated lymphatic vessels control T cell exit from tumors via the chemokine CXCL12, and intratumoral antigen encounter tunes CXCR4 expression by effector CD8+ T cells. Only high-affinity antigen downregulates CXCR4 and upregulates the CXCL12 decoy receptor, ACKR3, thereby reducing CXCL12 sensitivity and promoting T cell retention. A diverse repertoire of functional tumor-specific CD8+ T cells, therefore, exit the tumor, which limits the pool of CD8+ T cells available to exert tumor control. CXCR4 inhibition or loss of lymphatic-specific CXCL12 boosts T cell retention and enhances tumor control. These data indicate that strategies to limit T cell egress might be an approach to boost the quantity and quality of intratumoral T cells and thereby response to immunotherapy.


Subject(s)
Lymphatic Vessels , Neoplasms , Humans , CD8-Positive T-Lymphocytes , Receptors, CXCR4/metabolism , Neoplasms/therapy , Neoplasms/pathology , Lymphatic Vessels/metabolism , Immunotherapy
5.
J Med Imaging (Bellingham) ; 7(1): 012706, 2020 Jan.
Article in English | MEDLINE | ID: mdl-34541020

ABSTRACT

Purpose: Pathologists rely on relevant clinical information, visual inspection of stained tissue slide morphology, and sophisticated molecular diagnostics to accurately infer the biological origin of secondary metastatic cancer. While highly effective, this process is expensive in terms of time and clinical resources. We seek to develop and evaluate a computer vision system designed to reasonably infer metastatic origin of secondary liver cancer directly from digitized histopathological whole slide images of liver biopsy. Approach: We illustrate a two-stage deep learning approach to accomplish this task. We first train a model to identify spatially localized regions of cancerous tumor within digitized hematoxylin and eosin (H&E)-stained tissue sections of secondary liver cancer based on a pathologist's annotation of several whole slide images. Then, a second model is trained to generate predictions of the cancers' metastatic origin belonging to one of three distinct clinically relevant classes as confirmed by immunohistochemistry. Results: Our approach achieves a classification accuracy of 90.2% in determining metastatic origin of whole slide images from a held-out test set, which compares favorably to an established clinical benchmark by three board-certified pathologists whose accuracies ranged from 90.2% to 94.1% on the same prediction task. Conclusions: We illustrate the potential impact of deep learning systems to leverage morphological and structural features of H&E-stained tissue sections to guide pathological and clinical determination of the metastatic origin of secondary liver cancers.

6.
Antonie Van Leeuwenhoek ; 105(6): 1163-72, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24777297

ABSTRACT

A rod shaped, non-motile, endospore forming, Gram-stain positive and moderately halotolerant strain, designated as NCCP-168(T), was isolated from salt mines sampled in the Karak district of Khyber Pakhtunkhwa Province in Pakistan. To delineate its taxonomic position, the strain was subjected to polyphasic characterization. Cells of strain NCCP-168(T) can grow at 10-40 (○)C (optimum at 30-35 (○)C), in a pH range of 5.0-9.0 (optimum at pH 8.0) and in 0-17 % (w/v) NaCl on agar medium. The phylogenetic analysis based on the 16S rRNA gene sequence showed that strain NCCP-168(T) belongs to the genus Bacillus with the highest similarity to Bacillus seohaeanensis BH724(T) (97.1 %), and less than 97 % similarity with other closely related taxa (95.6 % with B. subtilis subsp. subtilis NCIB3610(T)). DNA-DNA relatedness between strain NCCP-168(T) and the type strains of closely related species was lower than 30 %. Chemotaxonomic data (major menaquinone, MK-7; cell wall peptidoglycan type, A1γ [meso-diaminopimelic acid]; major fatty acids, iso-C15:0 29.9 %, anteiso-C15:0 29.3 %, iso-C16:0 11.4 %, iso-C14:0 8.9 % and anteiso-C17:0 7.0 %; major polar lipids, diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine) support the affiliation of strain NCCP-168(T) with genus Bacillus. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain NCCP-168(T) can be distinguished from the closely related taxa and thus represents a novel species in the genus Bacillus, for which the name Bacillus pakistanensis sp. nov. is proposed, with the type strain NCCP-168(T) (= KCTC 13786(T) = DSM 24834(T) = JCM 18975(T)).


Subject(s)
Bacillus/classification , Bacillus/isolation & purification , Salts/toxicity , Soil Microbiology , Bacillus/genetics , Bacillus/physiology , Bacterial Typing Techniques , Cell Wall/chemistry , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Diaminopimelic Acid/analysis , Drug Tolerance , Fatty Acids/analysis , Hydrogen-Ion Concentration , Molecular Sequence Data , Nucleic Acid Hybridization , Pakistan , Peptidoglycan/chemistry , Phospholipids/analysis , Phylogeny , Quinones/analysis , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Sodium Chloride/metabolism , Temperature
7.
Antonie Van Leeuwenhoek ; 105(2): 325-33, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24281734

ABSTRACT

The taxonomic status of a bacterium, strain NCCP-246(T), isolated from rhizosphere of Vigna mungo, was determined using a polyphasic taxonomic approach. The strain NCCP-246(T) can grow at 16-37 °C (optimum 32 °C), at pH ranges of 6-8 (optimum growth occurs at pH 7) and in 0-4 % (w/v) NaCl. Phylogenetic analysis based upon on 16S rRNA gene sequence comparison revealed that strain NCCP-246(T) belonged to genus Sphingobacterium. Strain NCCP-246(T) showed highest similarity to the type strain of Sphingobacterium canadense CR11(T) (97.67 %) and less than 97 % with other species of the genus. The DNA-DNA relatedness value of strain NCCP-246(T) with S. canadense CR11(T) and Sphingobacterium thalpophilum JCM 21153(T) was 55 and 44.4 %, respectively. The chemotaxonomic data revealed the major menaquinone as MK-7 and dominant cellular fatty acids were summed feature 3 [C16:1 ω7c/C16:1 ω6c] (37.07 %), iso-C15:0 (28.03 %), C16:0 (11.85 %), C17:0 cyclo (8.84 %) and C14:0 (2.42 %). The G+C content of the strain was 39.2 mol%. On the basis of DNA-DNA hybridization, phylogenetic analyses, physiological and, biochemical data, strain NCCP-246(T) can be differentiated from the validly named members of genus Sphingobacterium and thus represents as a new species, for which the name, Sphingobacterium pakistanensis sp. nov. is proposed with the type strain NCCP-246(T) (= JCM18974 (T) = KCTC 23914(T)).


Subject(s)
Fabaceae/microbiology , Plant Growth Regulators/metabolism , Rhizosphere , Soil Microbiology , Sphingobacterium/classification , Sphingobacterium/isolation & purification , Bacterial Typing Techniques , Base Composition , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Fatty Acids/analysis , Molecular Sequence Data , Nucleic Acid Hybridization , Phylogeny , Quinones/analysis , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Sphingobacterium/genetics , Sphingobacterium/metabolism
8.
Semin Intervent Radiol ; 24(3): 303-6, 2007 Sep.
Article in English | MEDLINE | ID: mdl-21326473

ABSTRACT

Common interventional procedures on frequently encountered patients may wrongly place one on a track that deals with the task at hand while not assessing the global patient. Nowhere is this more problematic than in the dialysis population where in the course of achieving and maintaining vascular access, the interventionist becomes exceedingly familiar with each patient and his or her particular clinical history. Unfortunately, events that may have occurred in the past few hours may rarely be overlooked. We present a case of patient mortality as an indirect result of an upper extremity polytetrafluoroethylene graft thrombectomy-thrombolysis procedure that followed attempted nontunneled catheter placement via the groin.

9.
Semin Intervent Radiol ; 24(3): 307-11, 2007 Sep.
Article in English | MEDLINE | ID: mdl-21326474

ABSTRACT

The purpose of this morbidity and mortality case report is to discuss a characteristic of the Viabahn (W.L. Gore, Newark, DE) stent-graft deployment as well as a complication related to wire trauma during endovascular exclusion of a popliteal artery aneurysm. We encountered a phenomenon not described in the literature during deployment of a Viabahn stent graft. This necessitated further wire purchase, which resulted in perforation of a branch vessel within the calf. The rapid recognition of the clinical findings and prompt diagnosis of compartment syndrome was essential to early intervention, which prevented further complication and permanent sequelae.

10.
Chem Res Toxicol ; 17(9): 1217-26, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15377155

ABSTRACT

It is well-established that at pH 7.4, intramolecular 1,3-N-alkylation reactions in isophosphoramide mustard (IPM) and phosphoramide mustard (PM) produce electrophilic alkylating agents with aziridinyl moieties. To investigate the role of 1,5-intramolecular cyclizations in the chemistry of IPM and PM, the five-membered ring phospholidine products of these reactions were independently synthesized and characterized by (31)P NMR. In 0.33 M BisTris, pH 7.4, 37 degrees C, the intramolecular O-alkylation product of IPM [2-(2-chloroethylamino)-2-tetrahydro-2H-1,3,2-oxazaphospholidine-2-oxide (11)] had a chemical shift of delta 33.0 and a half-life of 3.3 h. The O-alkylation product of PM [2-amino-3-(2-chloroethyl)tetrahydro-2H-1,3,2-oxazaphospholidine-2-oxide (12)] displayed a chemical shift of delta 30.6 and a half-life of 26.9 h. For both IPM and PM, 1,5-N-alkylation provides the same product [1-(2-chloroethyl)-2-hydroxy-tetrahydro-2H-1,3,2-diazaphospholidine-2-oxide (13)]. Because of its instability, 13 was generated in situ and was not isolated; however, the chemical shift (delta 33.0) and reactivity (half-life 0.3 h at 25 degrees C) of the species attributed to 13 were consistent with the assigned structure. Resonances with (31)P NMR chemical shifts indicative of 11 or 12 did not appear in reaction solutions of IPM or PM. The compound assigned as 13 gave hydrolysis products that were not found in reaction solutions of IPM or PM. The collective data supported the conclusion that intramolecular 1,5-alkylations do not contribute to the chemistry of IPM or PM in aqueous solutions at pH 7.4, 37 degrees C. Conversely, 11 and 12 were found to be the major if not exclusive products formed in DMSO solutions of the respective cyclohexylammonium salts of IPM and PM. Both 11 and 12 were relatively noncytotoxic against a series of cell lines, but there were differences in mutagenicities. Chinese hamster ovary cells were exposed to 11 or 12 for one half-life of each compound; 11 was nonmutagenic up to 500 microM, while 12 (500 microM) was mutagenic with 246 mutant colonies/10(6) surviving cells.


Subject(s)
Aziridines/chemistry , Phosphoramide Mustards/chemistry , Alkylation , Animals , Aziridines/metabolism , Aziridines/toxicity , CHO Cells , Cell Line , Cricetinae , Humans , Mutagenicity Tests , Phosphoramide Mustards/metabolism , Phosphoramide Mustards/toxicity , Toxicity Tests
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