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1.
Nat Immunol ; 25(4): 703-715, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38514887

ABSTRACT

Analysis of the human hematopoietic progenitor compartment is being transformed by single-cell multimodal approaches. Cellular indexing of transcriptomes and epitopes by sequencing (CITE-seq) enables coupled surface protein and transcriptome profiling, thereby revealing genomic programs underlying progenitor states. To perform CITE-seq systematically on primary human bone marrow cells, we used titrations with 266 CITE-seq antibodies (antibody-derived tags) and machine learning to optimize a panel of 132 antibodies. Multimodal analysis resolved >80 stem, progenitor, immune, stromal and transitional cells defined by distinctive surface markers and transcriptomes. This dataset enables flow cytometry solutions for in silico-predicted cell states and identifies dozens of cell surface markers consistently detected across donors spanning race and sex. Finally, aligning annotations from this atlas, we nominate normal marrow equivalents for acute myeloid leukemia stem cell populations that differ in clinical response. This atlas serves as an advanced digital resource for hematopoietic progenitor analyses in human health and disease.


Subject(s)
Hematopoietic Stem Cells , Transcriptome , Humans , Bone Marrow , Gene Expression Profiling , Bone Marrow Cells
2.
Res Sq ; 2023 Oct 09.
Article in English | MEDLINE | ID: mdl-37886517

ABSTRACT

Oral mucosal colonization by C. albicans (Ca) is benign in healthy people but progresses to deeper infection known as oropharyngeal candidiasis (OPC) that may become disseminated when combined with immunosuppression. Cortisone-induced immunosuppression is a well-known risk factor for OPC, however the mechanism by which it permits infection is poorly understood. Neutrophils are the primary early sentinels preventing invasive fungal growth, and here we identify that in vivo neutrophil functional complexes known as swarms are crucial for preventing Ca invasion which are disrupted by cortisone. Neutrophil swarm function required leukotriene B4 receptor 1 (BLT1) expression, and swarms were further characterized by peripheral association of polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) showing that OPC recruits PMN-MDSCs to this site of infection. Furthermore, PMN-MDSCs associated with Ca hyphae had no direct antifungal effect but showed prolonged survival times and increased autophagy. Thus in vivo neutrophil swarms are complex structures with spatially associated PMN-MDSCs that likely contribute immunoregulatory functions to resolve OPC. These swarm structures have an important function in preventing deep invasion by Ca within the oral mucosa and represent a mechanism for increased disease severity under immune deficient clinical settings.

3.
mSphere ; 5(4)2020 08 05.
Article in English | MEDLINE | ID: mdl-32759336

ABSTRACT

Phagocytic cells are crucial components of the innate immune system preventing Candida albicans mucosal infections. Streptococcus gordonii and Pseudomonas aeruginosa often colonize mucosal sites, along with C. albicans, and yet interkingdom interactions that might alter the survival and escape of fungi from macrophages are not understood. Murine macrophages were coinfected with S. gordonii or P. aeruginosa, along with C. albicans to evaluate changes in fungal survival. S. gordonii increased C. albicans survival and filamentation within macrophage phagosomes, while P. aeruginosa reduced fungal survival and filamentation. Coinfection with S. gordonii resulted in greater escape of C. albicans from macrophages and increased size of fungal microcolonies formed on macrophage monolayers, while coinfection with P. aeruginosa reduced macrophage escape and produced smaller microcolonies. Microcolonies formed in the presence of P. aeruginosa cells outside macrophages also had significantly reduced size that was not found with P. aeruginosa phenazine deletion mutants. S. gordonii cells, as well as S. gordonii heat-fixed culture supernatants, increased C. albicans microcolony biomass but also resulted in microcolony detachment. A heat-resistant, trypsin-sensitive pheromone processed by S. gordonii Eep was needed for these effects. The majority of fungal microcolonies formed on human epithelial monolayers with S. gordonii supernatants developed as large floating structures with no detectable invasion of epithelium, along with reduced gene expression of C. albicansHYR1, EAP1, and HWP2 adhesins. However, a subset of C. albicans microcolonies was smaller and had greater epithelial invasiveness compared to microcolonies grown without S. gordonii Thus, bacteria can alter the killing and escape of C. albicans from macrophages and contribute to changes in C. albicans pathogenicity.IMPORTANCECandida albicans is the predominant fungus colonizing the oral cavity that can have both synergistic and antagonistic interactions with other bacteria. Interkingdom polymicrobial associations modify fungal pathogenicity and are believed to increase microbial resistance to innate immunity. However, it is not known how these interactions alter fungal survival during phagocytic killing. We demonstrated that secreted molecules of S. gordonii and P. aeruginosa alter C. albicans survival within the phagosome of macrophages and alter fungal pathogenic phenotypes, including filamentation and microcolony formation. Moreover, we provide evidence for a dual interaction between S. gordonii and C. albicans such that S. gordonii signaling peptides can promote C. albicans commensalism by decreasing microcolony attachment while increasing invasion in epithelial cells. Our results identify bacterial diffusible factors as an attractive target to modify virulence of C. albicans in polymicrobial infections.


Subject(s)
Bacteria/metabolism , Candida albicans/physiology , Hyphae/growth & development , Macrophages/microbiology , Microbial Interactions , Phagosomes/microbiology , Animals , Bacteria/genetics , Bacterial Adhesion , Candida albicans/pathogenicity , Epithelial Cells/microbiology , Mice , Mouth/microbiology , Pseudomonas aeruginosa/genetics , Pseudomonas aeruginosa/physiology , RAW 264.7 Cells , Streptococcus gordonii/genetics , Streptococcus gordonii/physiology , Virulence
4.
Article in English | MEDLINE | ID: mdl-30718249

ABSTRACT

Candida albicans, the causative agent of mucosal infections, including oropharyngeal candidiasis (OPC), as well as bloodstream infections, is becoming increasingly resistant to existing treatment options. In the absence of novel drug candidates, drug repurposing aimed at using existing drugs to treat off-label diseases is a promising strategy. C. albicans requires environmental iron for survival and virulence, while host nutritional immunity deploys iron-binding proteins to sequester iron and reduce fungal growth. Here we evaluated the role of iron limitation using deferasirox (an FDA-approved iron chelator for the treatment of patients with iron overload) during murine OPC and assessed deferasirox-treated C. albicans for its interaction with human oral epithelial (OE) cells, neutrophils, and antimicrobial peptides. Therapeutic deferasirox treatment significantly reduced salivary iron levels, while a nonsignificant reduction in the fungal burden was observed. Preventive treatment that allowed for two additional days of drug administration in our murine model resulted in a significant reduction in the number of C. albicans CFU per gram of tongue tissue, a significant reduction in salivary iron levels, and significantly reduced neutrophil-mediated inflammation. C. albicans cells harvested from the tongues of animals undergoing preventive treatment had the differential expression of 106 genes, including those involved in iron metabolism, adhesion, and the response to host innate immunity. Moreover, deferasirox-treated C. albicans cells had a 2-fold reduction in survival in neutrophil phagosomes (with greater susceptibility to oxidative stress) and reduced adhesion to and invasion of OE cells in vitro Thus, deferasirox treatment has the potential to alleviate OPC by affecting C. albicans gene expression and reducing virulence.


Subject(s)
Candida albicans/drug effects , Candidiasis, Oral/drug therapy , Deferasirox/pharmacology , Epithelial Cells/microbiology , Iron Chelating Agents/pharmacology , Mouth Mucosa/microbiology , Animals , Antifungal Agents/pharmacology , Candida albicans/pathogenicity , Candidiasis, Oral/microbiology , Candidiasis, Oral/pathology , Cell Adhesion/drug effects , Cells, Cultured , Drug Repositioning , Female , Gene Expression Regulation, Fungal/drug effects , Humans , Iron/metabolism , Mice , Mice, Inbred C57BL , Mouth Mucosa/cytology , Mouth Mucosa/pathology , Neutrophils/microbiology , Oxidative Stress/drug effects , Saliva/chemistry , Tongue/microbiology
5.
Infect Immun ; 86(12)2018 12.
Article in English | MEDLINE | ID: mdl-30249746

ABSTRACT

Host phagocytic cells are crucial players in initial defense against Candida albicans infection. C. albicans utilizes MAP kinases and Ras1 stress response signaling pathways to protect itself from killing by immune cells. In this study, we tested the importance of these pathways in C. albicans phagocytosis by neutrophils and subsequent phagosomal survival. Phagocytosis was influenced by C. albicans morphology, so hyphal length of >10 µm reduced the phagocytic index (PI) 2- to 3-fold in human neutrophils. Primary human neutrophils killed 81% of phagocytosed C. albicans, while primary mouse neutrophils killed 63% of yeasts. We found that both the C. albicans Cek1 and Hog1 pathways were required for survival of phagocytosed yeast, whereas deletion of C. albicansRAS1 resulted in an 84% increase in survival within neutrophils compared to that of the wild type (WT). The absence of Ras1 did not alter reactive oxygen species (ROS) production by C. albicans; however, phagocytosed C. albicans Δ/Δras1 cells reduced ROS release by neutrophils by 86%. Moreover, C. albicans Δ/Δras1 cells had increased resistance to hydrogen peroxide as a result of high levels of catalase activity. This phenotype was specific to Ras1, since these effects were not observed in the absence of its partner Cyr1 or with its downstream target Efg1. In addition, C. albicans Δ/Δras1 cells had a significantly increased resistance to nonoxidative killing by human neutrophil peptide 1 (HNP-1) that was reversed by restoring cellular cAMP levels. These data show that C. albicans Ras1 inactivation leads to fungal resistance to both oxidative and nonoxidative mechanisms of neutrophil phagosomal killing.


Subject(s)
Candida albicans , Fungal Proteins/genetics , Neutrophils/immunology , Phagosomes/immunology , ras Proteins/genetics , Animals , Cells, Cultured , Female , Fungal Proteins/immunology , Gene Silencing , Host-Pathogen Interactions/immunology , Humans , Hyphae/immunology , Mice , Mice, Inbred C57BL , Oxidative Stress , Phagocytosis , Reactive Oxygen Species/metabolism , Signal Transduction , alpha-Defensins/pharmacology , ras Proteins/immunology
6.
Article in English | MEDLINE | ID: mdl-29158282

ABSTRACT

Candida auris is a newly identified species causing invasive candidemia and candidiasis. It has broad multidrug resistance (MDR) not observed for other pathogenic Candida species. Histatin 5 (Hst 5) is a well-studied salivary cationic peptide with significant antifungal activity against Candida albicans and is an attractive candidate for treating MDR fungi, since antimicrobial peptides induce minimal drug resistance. We investigated the susceptibility of C. auris to Hst 5 and neutrophils, two first-line innate defenses in the human host. The majority of C. auris clinical isolates, including fluconazole-resistant strains, were highly sensitive to Hst 5: 55 to 90% of cells were killed by use of 7.5 µM Hst 5. Hst 5 was translocated to the cytosol and vacuole in C. auris cells; such translocation is required for the killing of C. albicans by Hst 5. The inverse relationship between fluconazole resistance and Hst 5 killing suggests different cellular targets for Hst 5 than for fluconazole. C. auris showed higher tolerance to oxidative stress than C. albicans, and higher survival within neutrophils, which correlated with resistance to oxidative stress in vitro Thus, resistance to reactive oxygen species (ROS) is likely one, though not the only, important factor in the killing of C. auris by neutrophils. Hst 5 has broad and potent candidacidal activity, enabling it to combat MDR C. auris strains effectively.


Subject(s)
Antifungal Agents/pharmacology , Candida/drug effects , Candidiasis/drug therapy , Drug Resistance, Multiple, Fungal/drug effects , Fluconazole/pharmacology , Histatins/pharmacology , Candida/metabolism , Candida albicans/drug effects , Candida albicans/metabolism , Candidiasis/microbiology , Fungal Proteins/metabolism , Humans , Peptides/metabolism , Vacuoles/drug effects
7.
Int. j. odontostomatol. (Print) ; 7(3): 427-432, Dec. 2013. ilus
Article in English | LILACS | ID: lil-696574

ABSTRACT

We report on a patient who presented to ENT services with right side epistaxis, frontal lobe headache, right infraorbital pain and the feeling of having a stuffy nose. CT and MRI were performed and later a biopsy confirmed the presence of sinonasal plasmocytoma. The Head and Neck oncology committee recommended radiotherapy as the choice of treatment. At the present time the patient is being followed on scheduled medical visits.


Se reporta el caso de un paciente que se presentó en el servicio de Otorrinolaringología con epistaxis, cefalea del lóbulo frontal derecho, dolor infraorbitario derecho y la sensación de tener la nariz tapada. Se realizaron TC y RNM, y luego una biopsia confirmó la presencia de un plasmocitoma nasosinusal. El comité de oncología de cabeza y cuello recomendó radioterapia como tratamiento de elección. En la actualidad, el paciente está en siguimiento y control en las visitas médicas regulares.


Subject(s)
Humans , Male , Middle Aged , Magnetic Resonance Imaging , Nose Neoplasms/diagnosis , Plasmacytoma/diagnosis , Tomography, X-Ray Computed , Nose Neoplasms/radiotherapy , Plasmacytoma/radiotherapy
8.
Int. j. odontostomatol. (Print) ; 6(3): 296-301, 2012. ilus
Article in English | LILACS | ID: lil-676189

ABSTRACT

We present the case of a patient, a 59 year-old man, with Sinonasal Adenoid Cystic Carcinoma. Magnetic resonance exam revealed invasion of the right orbit and brain at the level of the anterior cranial fossa floor. Due to the large volume, we decided to perform radio-chemotherapy treatment to diminish the size of the lesion. On conclusion of the first stage of treatment, reduction in tumor size was confirmed by computerized tomography exam and we decided to perform surgical resection with right ocular globe preservation. At present the patient is under periodic control and without major complications...


Se presenta el caso de un paciente de sexo masculino de 59 años con carcinoma adenoide quístico nasosinusal. El examen de resonancia magnética reveló la invasión de la órbita derecha y el cerebro a nivel del suelo de la fosa craneal anterior. Debido al gran volumen, se decidió realizar el tratamiento de radio-quimioterapia para disminuir el tamaño de la lesión. Al término de la primera etapa del tratamiento, la reducción del tamaño del tumor fue confirmada por el examen de tomografía computarizada y se decidió realizar una resección quirúrgica con preservación del globo ocular derecho. En la actualidad el paciente se encuentra bajo el control periódico y sin mayores complicaciones...


Subject(s)
Humans , Male , Middle Aged , Carcinoma, Adenoid Cystic/surgery , Carcinoma, Adenoid Cystic/diagnosis , Paranasal Sinus Neoplasms/surgery , Paranasal Sinus Neoplasms/diagnosis , Carcinoma, Adenoid Cystic/pathology , Magnetic Resonance Imaging , Paranasal Sinus Neoplasms/pathology , Tomography, X-Ray Computed
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