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1.
Science ; 384(6694): 428-437, 2024 Apr 26.
Article En | MEDLINE | ID: mdl-38662827

A role for vitamin D in immune modulation and in cancer has been suggested. In this work, we report that mice with increased availability of vitamin D display greater immune-dependent resistance to transplantable cancers and augmented responses to checkpoint blockade immunotherapies. Similarly, in humans, vitamin D-induced genes correlate with improved responses to immune checkpoint inhibitor treatment as well as with immunity to cancer and increased overall survival. In mice, resistance is attributable to the activity of vitamin D on intestinal epithelial cells, which alters microbiome composition in favor of Bacteroides fragilis, which positively regulates cancer immunity. Our findings indicate a previously unappreciated connection between vitamin D, microbial commensal communities, and immune responses to cancer. Collectively, they highlight vitamin D levels as a potential determinant of cancer immunity and immunotherapy success.


Bacteroides fragilis , Gastrointestinal Microbiome , Immune Checkpoint Inhibitors , Neoplasms , Vitamin D , Animals , Female , Humans , Male , Mice , Bacteroides fragilis/metabolism , Gastrointestinal Microbiome/drug effects , Immune Checkpoint Inhibitors/therapeutic use , Immune Checkpoint Inhibitors/pharmacology , Immunotherapy , Intestinal Mucosa/immunology , Intestinal Mucosa/microbiology , Intestinal Mucosa/metabolism , Mice, Inbred C57BL , Neoplasms/immunology , Neoplasms/microbiology , Neoplasms/therapy , Vitamin D/administration & dosage , Vitamin D/metabolism , Diet , Cell Line, Tumor , Calcifediol/administration & dosage , Calcifediol/metabolism , Vitamin D-Binding Protein/genetics , Vitamin D-Binding Protein/metabolism
2.
Immunity ; 57(4): 700-717, 2024 Apr 09.
Article En | MEDLINE | ID: mdl-38599166

C-type lectin receptors (CLRs) expressed by myeloid cells constitute a versatile family of receptors that play a key role in innate immune recognition. Myeloid CLRs exhibit a remarkable ability to recognize an extensive array of ligands, from carbohydrates and beyond, and encompass pattern-associated molecular patterns (PAMPs), damage-associated molecular patterns (DAMPs), and markers of altered self. These receptors, classified into distinct subgroups, play pivotal roles in immune recognition and modulation of immune responses. Their intricate signaling pathways orchestrate a spectrum of cellular responses, influencing processes such as phagocytosis, cytokine production, and antigen presentation. Beyond their contributions to host defense in viral, bacterial, fungal, and parasitic infections, myeloid CLRs have been implicated in non-infectious diseases such as cancer, allergies, and autoimmunity. A nuanced understanding of myeloid CLR interactions with endogenous and microbial triggers is starting to uncover the context-dependent nature of their roles in innate immunity, with implications for therapeutic intervention.


Lectins, C-Type , Neoplasms , Humans , Lectins, C-Type/metabolism , Immunity, Innate , Myeloid Cells/metabolism , Signal Transduction , Neoplasms/metabolism , Receptors, Pattern Recognition/metabolism
3.
Nat Immunol ; 25(3): 448-461, 2024 Mar.
Article En | MEDLINE | ID: mdl-38351322

Conventional dendritic cells (cDCs) include functionally and phenotypically diverse populations, such as cDC1s and cDC2s. The latter population has been variously subdivided into Notch-dependent cDC2s, KLF4-dependent cDC2s, T-bet+ cDC2As and T-bet- cDC2Bs, but it is unclear how all these subtypes are interrelated and to what degree they represent cell states or cell subsets. All cDCs are derived from bone marrow progenitors called pre-cDCs, which circulate through the blood to colonize peripheral tissues. Here, we identified distinct mouse pre-cDC2 subsets biased to give rise to cDC2As or cDC2Bs. We showed that a Siglec-H+ pre-cDC2A population in the bone marrow preferentially gave rise to Siglec-H- CD8α+ pre-cDC2As in tissues, which differentiated into T-bet+ cDC2As. In contrast, a Siglec-H- fraction of pre-cDCs in the bone marrow and periphery mostly generated T-bet- cDC2Bs, a lineage marked by the expression of LysM. Our results showed that cDC2A versus cDC2B fate specification starts in the bone marrow and suggest that cDC2 subsets are ontogenetically determined lineages, rather than cell states imposed by the peripheral tissue environment.


Dendritic Cells , Sialic Acid Binding Immunoglobulin-like Lectins , Animals , Mice , Cell Differentiation
4.
J Vasc Surg Venous Lymphat Disord ; 12(2): 101703, 2024 Mar.
Article En | MEDLINE | ID: mdl-37977519

OBJECTIVE: The aim of this study was to compare the outcomes and complications of selected patients treated with endovenous laser ablation (EVLA) or ambulatory phlebectomy for foot varicose veins. METHODS: From October 2016 to February 2022, selected patients undergoing EVLA (using 1470-nm with radial-slim or bare-tip fibers) or phlebectomy of foot varicose veins for cosmetic indications were analyzed, and the outcomes were compared. Patients were classified according to the Clinical, Etiologic, Anatomical, and Pathophysiological (CEAP) classification. Anatomic criteria provided the basis for the decision to perform EVLA or phlebectomy. Clinical and ultrasound assessments were performed on postoperative days 7, 30, and 90 for visualization of the sapheno-femoral and sapheno-popliteal junctions and the deep venous system. Disease severity was graded with the Venous Clinical Severity Score (VCSS), and quality of life was measured with the Aberdeen Varicose Vein Questionnaire (AVVQ) before and after treatment. Treatment outcomes were evaluated based on changes in VCSS and AVVQ scores. The groups were also compared for procedure-related complications. Data were statistically analyzed in SPSS v. 20.0 using the χ2, Student t test, Mann-Whitney test, Wilcoxon test, and analysis of variance. The results were presented as mean (standard deviation or median (interquartile range). RESULTS: The study included 270 feet of 171 patients. Mean patient age was 52.3 (standard deviation, 13.1) years, ranging from 21 to 84 years; 133 (77.8%) were women. Of 270 feet, 113 (41.9%) were treated with EVLA and 157 (58.1%) with phlebectomy. The median preoperative CEAP class was 2 (interquartile range, 2-3) in the phlebectomy and EVLA groups, with no statistically significant difference between the groups (P = .507). Dysesthesia was the most common complication in both groups. Only transient induration was significantly different between EVLA (7.1%) and phlebectomy (0.0%) (P = .001). The two approaches had an equal impact on quality of life and disease severity. CONCLUSIONS: Treatment complications were similar in phlebectomy and EVLA and to those previously described in the literature.


Laser Therapy , Varicose Veins , Venous Insufficiency , Humans , Female , Adolescent , Male , Quality of Life , Saphenous Vein/diagnostic imaging , Saphenous Vein/surgery , Varicose Veins/diagnostic imaging , Varicose Veins/surgery , Varicose Veins/etiology , Laser Therapy/adverse effects , Laser Therapy/methods , Treatment Outcome , Surveys and Questionnaires , Venous Insufficiency/diagnostic imaging , Venous Insufficiency/surgery , Venous Insufficiency/etiology
5.
Phlebology ; 39(1): 37-43, 2024 Feb.
Article En | MEDLINE | ID: mdl-37861200

OBJECTIVE: To comparatively evaluate performances of tablet-based versus paper-based Venous Insufficiency Epidemiologic and Economic Study-Quality of Life/Symptom (VEINES-QOL/Sym) questionnaire. METHODS: We prospectively evaluated 78 consecutive patients who completed tablet-based and paper-based VEINES-QOL/Sym questionnaires and compared their scores, completion time, data entry time, and ease of use. We used Student's t-test and Wilcoxon test for quantitative variables, Bland-Altman test and kappa coefficient for agreement between questionnaires and patients, respectively. Spearman's correlation coefficient was used to assess correlations. RESULTS: Most participants (83.3%) found it easier to use the tablet device. Less time was needed to complete the tablet-based (median, 4.75; IQR, 3-7 min) than the paper-based (median, 8.3; IQR, 6.3-11.3 min) questionnaire (p < .001). Better educated patients took less time to complete paper-based (p = .003) and tablet-based (p = .001) questionnaires and considered the latter easier to use (p = .010). CONCLUSIONS: The tablet-based VEINES-QOL/Sym proved to be an easy-to-use and time-saving tool.


Quality of Life , Venous Insufficiency , Humans , Venous Insufficiency/diagnosis , Venous Insufficiency/epidemiology , Veins , Surveys and Questionnaires , Chronic Disease
6.
Cureus ; 15(10): e46988, 2023 Oct.
Article En | MEDLINE | ID: mdl-38021502

Infective endocarditis (IE) is a relatively common disease that can manifest as a spectrum of clinical findings. Clinical awareness is key for the diagnosis. We present a case of a 14-year-old adolescent with fever, coughing, skin lesions, lip drooping, and quadrantanopia. Lumbar puncture was unremarkable and a head CT scan showed ischemic lesions. Blood cultures were positive for Staphylococcus aureus. A transesophageal echocardiogram showed a 7 x 7 mm mitral valve vegetation. The diagnosis of IE was made and flucloxacillin was initiated. Clinical suspicion was decisive for diagnosis. This case illustrates a serious and atypical presentation of an already uncommon disease in a patient without known risk factors for IE. While the initial cardiology workup was negative, a high clinical suspicion should always motivate further investigation as the consequences of untreated acute endocarditis are serious and life-threatening.

7.
Cell Rep ; 42(12): 113506, 2023 12 26.
Article En | MEDLINE | ID: mdl-38019655

Cross-presentation of dead cell-associated antigens by conventional dendritic cells type 1 (cDC1s) is critical for CD8+ T cells response against many tumors and viral infections. It is facilitated by DNGR-1 (CLEC9A), an SYK-coupled cDC1 receptor that detects dead cell debris. Here, we report that DNGR-1 engagement leads to rapid activation of CBL and CBL-B E3 ligases to cause K63-linked ubiquitination of SYK and terminate signaling. Genetic deletion of CBL E3 ligases or charge-conserved mutation of target lysines within SYK abolishes SYK ubiquitination and results in enhanced DNGR-1-dependent antigen cross-presentation. We also find that cDC1 deficient in CBL E3 ligases are more efficient at cross-priming CD8+ T cells to dead cell-associated antigens and promoting host resistance to tumors. Our findings reveal a role for CBL-dependent ubiquitination in limiting cross-presentation of dead cell-associated antigens and highlight an axis of negative regulation of cDC1 activity that could be exploited to increase anti-tumor immunity.


Cross-Priming , Ubiquitin-Protein Ligases , CD8-Positive T-Lymphocytes , Proto-Oncogene Proteins c-cbl , Ubiquitination , Dendritic Cells , Syk Kinase
8.
Prosthet Orthot Int ; 2023 Sep 14.
Article En | MEDLINE | ID: mdl-37708337

Among the components of lower limb prostheses, a perfectly adapted prosthetic socket is crucial to a successful rehabilitation process. Thus, developing a more comfortable socket could improve the quality of life for transfemoral (TF) amputees. The objective of this case report was to compare 2 TF sockets by evaluating the relationship between socket stiffness and user comfort and their influence on functionality to improve the quality of life of TF amputees. The participant received 2 different sockets: (A) flexible Flixt® socket; (B) conventional socket. He used each socket for 90 days, and after that was submitted to an evaluation at the Gait Laboratory (kinematic and dynamic analyses), completed the Prosthesis Evaluation Questionnaire, and performed Timed Up and Go test, 6-Minute March Test (6MWT), 10-Meter Walk Test, and Amputee Mobility Predictor test. After results were analyzed, the socket that obtained the best degree of satisfaction was assigned to the amputee participant. Combined measures showed that socket B does not considerably change the kinematic parameters neither dynamics parameters namely at stance phase. At Prosthesis Evaluation Questionnaire results, socket A had a better rating than socket B. The results of the Timed Up and Go test, 6MWT, 10-Meter Walk Test, and Amputee Mobility Predictor test obtained identical values, except for the 6MWT. This case report shows evidence of participant satisfaction improvement when using the flexible socket. The study also demonstrates that both sockets are quite effective.

9.
Cell Rep ; 42(8): 112881, 2023 08 29.
Article En | MEDLINE | ID: mdl-37523265

Conventional dendritic cells (cDCs) are found in most tissues and play a key role in initiation of immunity. cDCs require constant replenishment from progenitors called pre-cDCs that develop in the bone marrow (BM) and enter the blood circulation to seed all tissues. This process can be markedly accelerated in response to inflammation (emergency cDCpoiesis). Here, we identify two populations of BM pre-cDC marked by differential expression of CXCR4. We show that CXCR4lo cells constitute the migratory pool of BM pre-cDCs, which exits the BM and can be rapidly mobilized during challenge. We further show that exit of CXCR4lo pre-cDCs from BM at steady state is partially dependent on CCR2 and that CCR2 upregulation in response to type I IFN receptor signaling markedly increases efflux during infection with influenza A virus. Our results highlight a fine balance between retention and efflux chemokine cues that regulates steady-state and emergency cDCpoiesis.


Bone Marrow , Dendritic Cells , Receptors, CCR2 , Receptors, CXCR4 , Bone Marrow/metabolism , Bone Marrow Cells/metabolism , Dendritic Cells/metabolism , Inflammation/metabolism , Receptors, CCR2/metabolism , Receptors, CXCR4/metabolism , Signal Transduction , Animals
11.
Ther Innov Regul Sci ; 57(4): 875-885, 2023 07.
Article En | MEDLINE | ID: mdl-37072651

Project Orbis was initiated in May 2019 by the Oncology Center of Excellence to facilitate faster patient access to innovative cancer therapies by providing a framework for concurrent submissions and review of oncology products among international partners. Since its inception, Australia's Therapeutic Goods Administration (TGA), Canada's Health Canada (HC), Singapore's Health Sciences Authority (HSA), Switzerland's Swissmedic (SMC), Brazil's National Health Surveillance Agency (ANVISA), United Kingdom's Medicines and Healthcare Products Regulatory Agency (MHRA), and most recently Israel's Ministry of Health (IMoH) Medical Technologies, Health Information, Innovation and Research (MTIIR) Directorate, have joined Project Orbis. While each country has its own expedited review pathways to bring promising therapies to patients, there are some similarities and differences in pathways and timelines. FDA's fast-track designation and MHRA's marketing authorization under exceptional circumstances (MAEC) allow non-clinical and limited clinical evidence to support approval under these programs. HC's Extraordinary Use New Drug (EUND) pathway allows granting exceptional use authorization with limited clinical evidence. ANVISA, HSA, MTIIR, and TGA do not have standard pathways that allow non-clinical evidence and limited clinical evidence. While there is no definite regulatory pathway for HSA, the current framework for approval does allow flexibility in the type of data (non-clinical or clinical) required to demonstrate the benefit-risk profile of a product. HSA may register a product if the agency is satisfied that the overall benefit outweighs the risk. All Project Orbis Partner (POP) countries have similar programs to the FDA accelerated approval program except ANVISA. Although HSA and MTIIR do not have defined pathways for accelerated approval programs, there are opportunities to request accelerated approval per these agencies. All POP countries have pathways like the FDA priority review except MHRA. Priority review timelines for new drugs range from 120 to 264 calendar days (cd). Standard review timelines for new drugs range from 180 to 365 cd.


Medicine , Neoplasms , United States , Humans , Drug Approval , United States Food and Drug Administration , Canada
12.
Semin Immunol ; 66: 101726, 2023 03.
Article En | MEDLINE | ID: mdl-36758378

Conventional dendritic cells type 1 (cDC1) are critical for inducing protective CD8+ T cell responses to tumour and viral antigens. In many instances, cDC1 access those antigens in the form of material internalised from dying tumour or virally-infected cells. How cDC1 extract dead cell-associated antigens and cross-present them in the form of peptides bound to MHC class I molecules to CD8+ T cells remains unclear. Here we review the biology of dendritic cell natural killer group receptor-1 (DNGR-1; also known as CLEC9A), a C-type lectin receptor highly expressed on cDC1 that plays a key role in this process. We highlight recent advances that support a function for DNGR-1 signalling in promoting inducible rupture of phagocytic or endocytic compartments containing dead cell debris, thereby making dead cell-associated antigens accessible to the endogenous MHC class I processing and presentation machinery of cDC1. We further review how DNGR-1 detects dead cells, as well as the functions of the receptor in anti-viral and anti-tumour immunity. Finally, we highlight how the study of DNGR-1 has opened new perspectives into cross-presentation, some of which may have applications in immunotherapy of cancer and vaccination against viral diseases.


Cross-Priming , Neoplasms , Humans , CD8-Positive T-Lymphocytes , Receptors, Immunologic , Antigens/metabolism , Dendritic Cells , Neoplasms/metabolism
13.
Ultrasound Obstet Gynecol ; 61(1): 109-113, 2023 01.
Article En | MEDLINE | ID: mdl-35793228

OBJECTIVE: To describe the feasibility of an ultrasound-guided repositioning technique for partially expelled intrauterine devices (IUDs) without use of sedation. METHODS: This was a descriptive feasibility study of patients with a partially expelled IUD managed in our outpatient clinic from January 2016 to February 2020. The partially expelled IUDs (vertical arm extending partially or entirely through the cervical canal) were repositioned at the uterine fundus using Hartmann alligator forceps under ultrasound guidance. Paracervical or intracervical anesthesia and prophylactic antibiotics were not used. Data related to the procedure and 6-month follow-up were extracted from patient medical records. The primary outcome was the success rate of the repositioning procedure, defined as ultrasound confirmation of the entire IUD located above the internal os. Secondary outcomes included the retention and expulsion rates of the repositioned IUD at 6 months after the procedure and description of complications. RESULTS: We included data from 55 women with a partially expelled IUD (35 levonorgestrel IUDs and 20 copper IUDs) referred for repositioning. Ultrasound-guided repositioning of the IUD was successful in 51 (92.7%) cases, while the procedure was not completed in four patients due to pain. Of the 55 procedures, 48 (87.3%) were performed by obstetrics and gynecology trainees under the supervision of a senior specialist. Among the 51 successfully repositioned IUDs, nine (17.6%) were expelled within 6 months after the procedure and six patients were lost to follow-up. No uterine perforation or infection-related complications occurred within 6 months of the procedure. CONCLUSION: The ultrasound-guided repositioning technique appears to be a safe and feasible approach for partially expelled IUDs. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.


Intrauterine Devices , Female , Humans , Pregnancy , Feasibility Studies , Ultrasonography, Interventional , Uterus/diagnostic imaging
14.
Braz. j. biol ; 83: e244123, 2023. tab
Article En | LILACS, VETINDEX | ID: biblio-1278562

Abstract Toll-like receptor 9 (TLR9) is an important component of the innate immune system and have been associated with several autoimmune diseases, such as Systemic Lupus Erythematosus (SLE). The aim of this study was to investigate polymorphisms in TLR9 gene in a Brazilian SLE patients group and their association with clinical manifestation, particularly Jaccoud's arthropathy (JA). We analyzed DNA samples from 204 SLE patients, having a subgroup of them presenting JA (n=24). A control group (n=133) from the same city was also included. TLR9 single nucleotide polymorphisms (SNPs) (−1237 C>T and +2848 G>A) were identified by sequencing analysis. The TLR9 gene genotype frequency was similar both in SLE patients and the control group. In the whole SLE population, an association between the homozygosis of allele C at position −1237 with psychosis and anemia (p < 0.01) was found. Likewise, the homozygosis of allele G at position +2848 was associated with a discoid rash (p < 0.05). There was no association between JA and TLR9 polymorphisms. These data show that TLR9 polymorphisms do not seem to be a predisposing factor for SLE in the Brazilian population, and that SNPs are not associated with JA.


Resumo O receptor Toll-like 9 (TLR9) é um componente importante do sistema imunológico inato e tem sido associado a várias doenças autoimunes, como o Lúpus Eritematoso Sistêmico (LES). O objetivo deste estudo foi investigar polimorfismos no gene TLR9 em um grupo de pacientes brasileiros com LES e sua associação com a manifestação clínica, particularmente a artropatia de Jaccoud (JA). Foram analisadas amostras de DNA de 204 pacientes com LES, e um subgrupo com JA (n=24). Um grupo de controle (n=133) da mesma cidade também foi incluído. Os polimorfismos de nucleotídeos únicos TLR9 (SNPs) (−1237 C>T e +2848 G>A) foram identificados pela análise de sequenciamento. A frequência do genótipo genético TLR9 foi semelhante tanto em pacientes com LES quanto no grupo controle. Em toda a população de LES, foi encontrada associação entre a homozigose do alelo C na posição −1237 com psicose e anemia (p < 0,01). Da mesma forma, a homozigose do alelo G na posição +2848 foi associada a uma erupção cutânea discoide (p < 0,05). Não houve associação entre polimorfismos JA e TLR9. Esses dados mostram que os polimorfismos TLR9 não parecem ser um fator predisponível para o LES na população brasileira, e que os SNPs não estão associados ao JA.


Humans , Toll-Like Receptor 9/genetics , Lupus Erythematosus, Systemic/genetics , Brazil , Pilot Projects , Genetic Predisposition to Disease/genetics , Gene Frequency/genetics
15.
Braz. j. biol ; 83: 1-5, 2023. tab
Article En | LILACS, VETINDEX | ID: biblio-1468819

Toll-like receptor 9 (TLR9) is an important component of the innate immune system and have been associated with several autoimmune diseases, such as Systemic Lupus Erythematosus (SLE). The aim of this study was to investigate polymorphisms in TLR9 gene in a Brazilian SLE patients group and their association with clinical manifestation, particularly Jaccoud’s arthropathy (JA). We analyzed DNA samples from 204 SLE patients, having a subgroup of them presenting JA (n=24). A control group (n=133) from the same city was also included. TLR9 single nucleotide polymorphisms (SNPs) (−1237 C>T and +2848 G>A) were identified by sequencing analysis. The TLR9 gene genotype frequency was similar both in SLE patients and the control group. In the whole SLE population, an association between the homozygosis of allele C at position −1237 with psychosis and anemia (p < 0.01) was found. Likewise, the homozygosis of allele G at position +2848 was associated with a discoid rash (p < 0.05). There was no association between JA and TLR9 polymorphisms. These data show that TLR9 polymorphisms do not seem to be a predisposing factor for SLE in the Brazilian population, and that SNPs are not associated with JA.


O receptor Toll-like 9 (TLR9) é um componente importante do sistema imunológico inato e tem sido associado a várias doenças autoimunes, como o Lúpus Eritematoso Sistêmico (LES). O objetivo deste estudo foi investigar polimorfismos no gene TLR9 em um grupo de pacientes brasileiros com LES e sua associação com a manifestação clínica, particularmente a artropatia de Jaccoud (JA). Foram analisadas amostras de DNA de 204 pacientes com LES, e um subgrupo com JA (n=24). Um grupo de controle (n=133) da mesma cidade também foi incluído. Os polimorfismos de nucleotídeos únicos TLR9 (SNPs) (−1237 C>T e +2848 G>A) foram identificados pela análise de sequenciamento. A frequência do genótipo genético TLR9 foi semelhante tanto em pacientes com LES quanto no grupo controle. Em toda a população de LES, foi encontrada associação entre a homozigose do alelo C na posição −1237 com psicose e anemia (p < 0,01). Da mesma forma, a homozigose do alelo G na posição +2848 foi associada a uma erupção cutânea discoide (p < 0,05). Não houve associação entre polimorfismos JA e TLR9. Esses dados mostram que os polimorfismos TLR9 não parecem ser um fator predisponível para o LES na população brasileira, e que os SNPs não estão associados ao JA.


Humans , Joint Diseases/genetics , Lupus Erythematosus, Systemic/genetics , Toll-Like Receptor 9/analysis
16.
Braz. j. biol ; 832023.
Article En | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469035

Abstract Toll-like receptor 9 (TLR9) is an important component of the innate immune system and have been associated with several autoimmune diseases, such as Systemic Lupus Erythematosus (SLE). The aim of this study was to investigate polymorphisms in TLR9 gene in a Brazilian SLE patients group and their association with clinical manifestation, particularly Jaccouds arthropathy (JA). We analyzed DNA samples from 204 SLE patients, having a subgroup of them presenting JA (n=24). A control group (n=133) from the same city was also included. TLR9 single nucleotide polymorphisms (SNPs) (1237 C>T and +2848 G>A) were identified by sequencing analysis. The TLR9 gene genotype frequency was similar both in SLE patients and the control group. In the whole SLE population, an association between the homozygosis of allele C at position 1237 with psychosis and anemia (p 0.01) was found. Likewise, the homozygosis of allele G at position +2848 was associated with a discoid rash (p 0.05). There was no association between JA and TLR9 polymorphisms. These data show that TLR9 polymorphisms do not seem to be a predisposing factor for SLE in the Brazilian population, and that SNPs are not associated with JA.


Resumo O receptor Toll-like 9 (TLR9) é um componente importante do sistema imunológico inato e tem sido associado a várias doenças autoimunes, como o Lúpus Eritematoso Sistêmico (LES). O objetivo deste estudo foi investigar polimorfismos no gene TLR9 em um grupo de pacientes brasileiros com LES e sua associação com a manifestação clínica, particularmente a artropatia de Jaccoud (JA). Foram analisadas amostras de DNA de 204 pacientes com LES, e um subgrupo com JA (n=24). Um grupo de controle (n=133) da mesma cidade também foi incluído. Os polimorfismos de nucleotídeos únicos TLR9 (SNPs) (1237 C>T e +2848 G>A) foram identificados pela análise de sequenciamento. A frequência do genótipo genético TLR9 foi semelhante tanto em pacientes com LES quanto no grupo controle. Em toda a população de LES, foi encontrada associação entre a homozigose do alelo C na posição 1237 com psicose e anemia (p 0,01). Da mesma forma, a homozigose do alelo G na posição +2848 foi associada a uma erupção cutânea discoide (p 0,05). Não houve associação entre polimorfismos JA e TLR9. Esses dados mostram que os polimorfismos TLR9 não parecem ser um fator predisponível para o LES na população brasileira, e que os SNPs não estão associados ao JA.

17.
Braz J Med Biol Res ; 55: e12272, 2022.
Article En | MEDLINE | ID: mdl-36197413

The study of the interaction of synthetic protoporphyrin IX (PpIXs) and protoporphyrin IX extracted from Harderian glands of ssp Rattus novergicus albinus rats (PpIXe) with bovine serum albumin (BSA) was conducted in water at pH 7.3 and pH 4.5 by optical absorption and fluorescence spectroscopies. PpIXs is present as H- and J-aggregates in equilibrium with themselves and with monomers. The PpIXs charge is 2- at pH 7.3 and 1- at pH 4.5. This increases its aggregation at pH 4.5 and shifts the equilibrium in favor of J-aggregates. In spite of electrostatic attraction at pH 4.5, where BSA is positive, the binding constant (Kb) of PpIXs to BSA is 20% less than that at pH 7.3, where BSA is negative. This occurs because higher aggregation of PpIXs at pH 4.5 reduces the observed Kb value. At both pHs, water-soluble PpIXe exists in the monomeric form with the charge of 1- and its Kb exceeds that of PpIXs. At pH 4.5, its Kb is 12 times higher than that at pH 7.3 due to electrostatic attraction between the positively charged BSA and the negatively charged PpIXe. The higher probability of PpIXe binding to BSA makes PpIXe more promising as a fluorescence probe for fluorescence diagnostics and as a photosensitizer for photodynamic therapy. The existence of PpIXe in the monomeric form can explain its faster cell internalization. Aggregation reduces quantum yields and lifetimes of the PpIXs excited states, which explains higher phototoxicity of PpIXe toward malignant cells compared with PpIXs.


Photosensitizing Agents , Serum Albumin, Bovine , Animals , Hydrogen-Ion Concentration , Photosensitizing Agents/pharmacology , Protoporphyrins , Rats , Serum Albumin , Water
18.
J Immunother Cancer ; 10(9)2022 09.
Article En | MEDLINE | ID: mdl-36162919

Type 1 conventional dendritic cells (cDC1) play a critical role in priming anticancer cytotoxic CD8+ T cells. DNGR-1 (a.k.a. CLEC9A) is a cDC1 receptor that binds to F-actin exposed on necrotic cancer and normal cells. DNGR-1 signaling enhances cross-presentation of dead-cell associated antigens, including tumor antigens. We have recently shown that secreted gelsolin (sGSN), a plasma protein, competes with DNGR-1 for binding to dead cell-exposed F-actin and dampens anticancer immunity. Here, we investigated the effects of loss of sGSN on various anticancer therapies that are thought to induce cell death and provoke an immune response to cancer. We compared WT (wildtype) with Rag1-/- , Batf3-/- , Clec9agfp/gfp , sGsn-/- or sGsn-/- Clec9agfp/gfp mice implanted with transplantable tumor cell lines, including MCA-205 fibrosarcoma, 5555 BrafV600E melanoma and B16-F10 LifeAct (LA)-ovalbumin (OVA)-mCherry melanoma. Tumor-bearing mice were treated with (1) doxorubicin (intratumoral) chemotherapy for MCA-205, (2) BRAF-inhibitor PLX4720 (oral gavage) targeted therapy for 5555 BrafV600E, and (3) X-ray radiotherapy for B16 LA-OVA-mCherry. We confirmed that efficient tumor control following each therapy requires an immunocompetent host as efficacy was markedly reduced in Rag1-/- compared with WT mice. Notably, across all the therapeutic modalities, loss of sGSN significantly enhanced tumor control compared with treated WT controls. This was an on-target effect as mice deficient in both sGSN and DNGR-1 behaved no differently from WT mice following therapy. In sum, we find that mice deficient in sGsn display enhanced DNGR-1-dependent responsiveness to chemotherapy, targeted therapy and radiotherapy. Our findings are consistent with the notion some cancer therapies induce immunogenic cell death (ICD), which mobilizes anticancer T cells. Our results point to cDC1 and DNGR-1 as decoders of ICD and to sGSN as a negative regulator of such decoding, highlighting sGSN as a possible target in cancer treatment. Further prospective studies are warranted to identify patients who may benefit most from inhibition of sGSN function.


Gelsolin , Melanoma, Experimental , Actins/metabolism , Animals , Antigens, Neoplasm/metabolism , CD8-Positive T-Lymphocytes , Doxorubicin/metabolism , Gelsolin/genetics , Gelsolin/metabolism , Homeodomain Proteins , Lectins, C-Type , Mice , Ovalbumin , Proto-Oncogene Proteins B-raf/metabolism , Receptors, Immunologic/metabolism
19.
Dev Cell ; 57(16): 1957-1975.e9, 2022 08 22.
Article En | MEDLINE | ID: mdl-35998585

Cells with latent stem ability can contribute to mammalian tissue regeneration after damage. Whether the central nervous system (CNS) harbors such cells remains controversial. Here, we report that DNGR-1 lineage tracing in mice identifies an ependymal cell subset, wherein resides latent regenerative potential. We demonstrate that DNGR-1-lineage-traced ependymal cells arise early in embryogenesis (E11.5) and subsequently spread across the lining of cerebrospinal fluid (CSF)-filled compartments to form a contiguous sheet from the brain to the end of the spinal cord. In the steady state, these DNGR-1-traced cells are quiescent, committed to their ependymal cell fate, and do not contribute to neuronal or glial lineages. However, trans-differentiation can be induced in adult mice by CNS injury or in vitro by culture with suitable factors. Our findings highlight previously unappreciated ependymal cell heterogeneity and identify across the entire CNS an ependymal cell subset wherein resides damage-responsive neural stem cell potential.


Neural Stem Cells , Animals , Cell Differentiation , Ependyma , Mammals , Mice , Neuroglia , Spinal Cord
20.
Rev Bras Parasitol Vet ; 31(2): e005322, 2022.
Article En | MEDLINE | ID: mdl-35792757

The parabasalid Pentatrichomonas hominis is generally considered to represent a symbiotic component of the gastrointestinal microbiota in a wide variety of vertebrate hosts including humans. Nevertheless, a limited number of studies have raised the possibility that it may act as a pathogen of humans, dogs, and pigs and that some human infections may have a zoonotic origin. Data from North America revealed an association between P. hominis and the bovine urogenital tract, principally in bulls and rarely in cows. The importance of this observation is linked to possible interference in the accurate diagnosis of the economically important venereal pathogen Tritrichomonas foetus. The current study employed culture-based and molecular methods to examine the preputial cavities of four breeding bulls, raised in open pasture in southeastern Brazil, for the presence of trichomonads. Motile protozoa were isolated from three of the bulls and were definitively identified as P. hominis based on nucleotide sequencing of polymerase chain reaction (PCR) amplicons derived from the ribosomal RNA operon (ITS1-5.8S rDNA-ITS2) of the parasite. The potential implications of these findings for bovine and human health are discussed.


Cattle Diseases , Dog Diseases , Swine Diseases , Trichomonas , Tritrichomonas foetus , Animals , Brazil , Cattle , Cattle Diseases/diagnosis , Cattle Diseases/parasitology , Dogs , Female , Male , Polymerase Chain Reaction/veterinary , Swine , Trichomonas/genetics , Tritrichomonas foetus/genetics
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