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1.
Artículo en Inglés | MEDLINE | ID: mdl-38963507

RESUMEN

Beta-defensins, identified from fishes, constitute a crucial category of antimicrobial peptides important in combating bacterial fish pathogens. The present investigation centers on the molecular and functional characterization of CsDef, a 63-amino acid beta-defensin antimicrobial peptide derived from snakehead murrel (Channa striata). The physicochemical attributes of CsDef align with the distinctive characteristics observed in AMPs. CsDef was recombinantly produced, and the recombinant peptide, rCsDef, exhibited notable antibacterial efficacy against bacterial fish pathogens with an MIC of 16 µM for V. proteolyticus. A. hydrophila exhibited 91% inhibition, E. tarda 92%, and V. harveyi 53% at 32 µM of rCsDef. The rCsDef exhibited a multifaceted mechanism of action against bacteria, i.e., through membrane depolarization, membrane permeabilization, and generation of ROS. The rCsDef was non-hemolytic to hRBCs and non-cytotoxic to normal mammalian cell line CHO-K1. However, it exhibited anticancer properties in MCF-7. rCsDef demonstrated notable stability with respect to pH, temperature, salt, metal ions, and proteases. These findings suggest it is a potential candidate molecule for prospective applications in aquaculture.

2.
Sci Rep ; 14(1): 15442, 2024 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-38965312

RESUMEN

The human intestinal tract is colonized with microorganisms, which present a diverse array of immunological challenges. A number of antimicrobial mechanisms have evolved to cope with these challenges. A key defense mechanism is the expression of inducible antimicrobial peptides (AMPs), such as beta-defensins, which rapidly inactivate microorganisms. We currently have a limited knowledge of mechanisms regulating the inducible expression of AMP genes, especially factors from the host required in these regulatory mechanisms. To identify the host factors required for expression of the beta-defensin-2 gene (HBD2) in intestinal epithelial cells upon a bacterial challenge, we performed a RNAi screen using a siRNA library spanning the whole human genome. The screening was performed in duplicate to select the strongest 79 and 110 hit genes whose silencing promoted or inhibited HBD2 expression, respectively. A set of 57 hits selected among the two groups of genes was subjected to a counter-screening and a subset was subsequently validated for its impact onto HBD2 expression. Among the 57 confirmed hits, we brought out the TLR5-MYD88 signaling pathway, but above all new signaling proteins, epigenetic regulators and transcription factors so far unrevealed in the HBD2 regulatory circuits, like the GATA6 transcription factor involved in inflammatory bowel diseases. This study represents a significant step toward unveiling the key molecular requirements to promote AMP expression in human intestinal epithelial cells, and revealing new potential targets for the development of an innovative therapeutic strategy aiming at stimulating the host AMP expression, at the era of antimicrobial resistance.


Asunto(s)
Células Epiteliales , Mucosa Intestinal , beta-Defensinas , Humanos , beta-Defensinas/metabolismo , beta-Defensinas/genética , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología , Células Epiteliales/metabolismo , Células Epiteliales/microbiología , Transducción de Señal , Regulación de la Expresión Génica , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Factor 88 de Diferenciación Mieloide/metabolismo , Factor 88 de Diferenciación Mieloide/genética , Interferencia de ARN
3.
Expert Rev Anti Infect Ther ; : 1-10, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38970163

RESUMEN

INTRODUCTION: Antimicrobial peptides (AMPs) are polypeptides with potent antimicrobial activity against a broad range of pathogenic microorganisms. Unlike conventional antibiotics, AMPs have rapid bactericidal activity, a low capacity for inducing resistance, and compatibility with the host immune system. A large body of data supports the antimicrobial activities of a large body of data supports the antimicrobial activities of the class of AMPs known as ß-defensins. This review provides a comprehensive analysis of the effects of ß-defensins against various pathogenic microorganism: bacteria, fungi, viruses, Mycoplasmas and Chlamydiae. The primary mechanisms of ß-defensins against pathogenic microorganisms include inhibition of biofilms formations, dissolution of membranes, disruption of cell walls, and inhibition of adhesion and receptor binding. Although further study and structural modifications are needed, ß-defensins are promising candidates for antimicrobial therapy. AREAS COVERED: This review describes the inhibitory effects of ß-defensins on various pathogenic microorganisms. Additionally, we focus on elucidating the mechanisms underlying their actions to provide, providing valuable references for the further study of ß-defensins. EXPERT OPINION: The biological activities and modes of action of ß-defensins provide powerful resources for clinical microbial infection management. Addressing the salt sensitivity and toxicity of ß-defensins may further enhance their potential applications.

4.
Int J Mol Sci ; 25(13)2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-39000442

RESUMEN

Human defensins are cysteine-rich peptides (Cys-rich peptides) of the innate immune system. Defensins contain an ancestral structural motif (i.e., γ-core motif) associated with the antimicrobial activity of natural Cys-rich peptides. In this study, low concentrations of human α- and ß-defensins showed microbicidal activity that was not associated with cell membrane permeabilization. The cell death pathway was similar to that previously described for human lactoferrin, also an immunoprotein containing a γ-core motif. The common features were (1) cell death not related to plasma membrane (PM) disruption, (2) the inhibition of microbicidal activity via extracellular potassium, (3) the influence of cellular respiration on microbicidal activity, and (4) the influence of intracellular pH on bactericidal activity. In addition, in yeast, we also observed (1) partial K+-efflux mediated via Tok1p K+-channels, (2) the essential role of mitochondrial ATP synthase in cell death, (3) the increment of intracellular ATP, (4) plasma membrane depolarization, and (5) the inhibition of external acidification mediated via PM Pma1p H+-ATPase. Similar features were also observed with BM2, an antifungal peptide that inhibits Pma1p H+-ATPase, showing that the above coincident characteristics were a consequence of PM H+-ATPase inhibition. These findings suggest, for the first time, that human defensins inhibit PM H+-ATPases at physiological concentrations, and that the subsequent cytosolic acidification is responsible for the in vitro microbicidal activity. This mechanism of action is shared with human lactoferrin and probably other antimicrobial peptides containing γ-core motifs.


Asunto(s)
Membrana Celular , ATPasas de Translocación de Protón , Humanos , Membrana Celular/metabolismo , Membrana Celular/efectos de los fármacos , ATPasas de Translocación de Protón/metabolismo , ATPasas de Translocación de Protón/antagonistas & inhibidores , Permeabilidad de la Membrana Celular/efectos de los fármacos , Antiinfecciosos/farmacología , Defensinas/farmacología , Defensinas/metabolismo , Concentración de Iones de Hidrógeno , Saccharomyces cerevisiae/metabolismo , beta-Defensinas/metabolismo , beta-Defensinas/farmacología , Lactoferrina/farmacología , Lactoferrina/metabolismo , Potasio/metabolismo , Pruebas de Sensibilidad Microbiana , Candida albicans/efectos de los fármacos
5.
J Transl Med ; 22(1): 666, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39020346

RESUMEN

BACKGROUND: The discovery of new prognostic biomarkers following spinal cord injury (SCI) is a rapidly growing field that could help uncover the underlying pathological mechanisms of SCI and aid in the development of new therapies. To date, this search has largely focused on the initial days after the lesion. However, during the subacute stage of SCI (weeks to months after the injury), there remains potential for sensorimotor recovery, and numerous secondary events develop in various organs. Additionally, the confounding effects of early interventions after the injury are less likely to interfere with the results. METHODS: In this study, we conducted an untargeted proteomics analysis to identify biomarkers of recovery in blood serum samples during the subacute phase of SCI patients, comparing those with strong recovery to those with no recovery between 30 and 120 days. We analyzed the fraction of serum that is depleted of the most abundant proteins to unmask proteins that would otherwise go undetected. Linear models were used to identify peptides and proteins related to neurological recovery and we validated changes in some of these proteins using Enzyme-linked Immunosorbent Assay (ELISA). RESULTS: Our findings reveal that differences in subacute recovery after SCI (from 30 to 120 days) are associated with an enrichment in proteins involved in inflammation, coagulation, and lipid metabolism. Technical validation using commercial ELISAs further confirms that high levels of SERPINE1 and ARHGAP35 are associated with strong neurological recovery, while high levels of CD300a and DEFA1 are associated with a lack of recovery. CONCLUSIONS: Our study identifies new candidates for biomarkers of neurological recovery and for novel therapeutic targets after SCI.


Asunto(s)
Proteómica , Recuperación de la Función , Traumatismos de la Médula Espinal , Humanos , Traumatismos de la Médula Espinal/sangre , Masculino , Femenino , Adulto , Persona de Mediana Edad , Biomarcadores/sangre , Proteínas Sanguíneas/metabolismo
6.
J Invest Dermatol ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38945438

RESUMEN

Pruritus is the leading symptom of dermatophytosis. Microsporium canis is one of the predominant dermatophytes causing dermatophytosis. However, the pruritogenic agents and the related molecular mechanisms of the dermatophyte M. canis remain poorly understood. Here, the secretion of the dermatophyte M. canis was found to dose-dependently evoke itch in mice. The fungal peptide micasin secreted from M. canis was then identified to elicit mouse significant scratching and itching responses. The peptide micasin was further revealed to directly activate mouse dorsal root ganglia (DRG) neurons to mediate the non-histaminergic itch. Knockout and antagonistic experiments demonstrated that MRGPRX1/C11/A1 rather than MRGPRX2/b2 activated by micasin contributed to pruritus. The chimera and mutation of MRGPRX1 showed that three domains (ECL3, TMH3 and TMH6) and four hydrophobic residues (Y99, F237, L240 and W241) of MRGPRX1 played the key role in micasin-triggered MRGPRX1 activation. Our study sheds light on the dermatophytosis-associated pruritus and may provide potential therapeutic targets and strategies against pruritus caused by dermatophytes.

7.
Mar Biotechnol (NY) ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38922559

RESUMEN

Antimicrobial peptides (AMPs), including beta-defensin from fish, are a crucial class of peptide medicines. The focus of the current study is the molecular and functional attributes of CmDef, a 63-amino acid beta-defensin AMP from Malabar trevally, Carangoides malabaricus. This peptide demonstrated typical characteristics of AMPs, including hydrophobicity, amphipathic nature, and +2.8 net charge. The CmDef was recombinantly expressed and the recombinant peptide, rCmDef displayed a strong antimicrobial activity against bacterial fish pathogens with an MIC of 8 µM for V. proteolyticus and 32 µM for A. hydrophila. The E. tarda and V. harveyi showed an inhibition of 94% and 54%, respectively, at 32 µM concentration. No activity was observed against V. fluvialis and V. alginolyticus. The rCmDef has a multimode of action that exerts an antibacterial effect by membrane depolarization followed by membrane permeabilization and ROS production. rCmDef also exhibited anti-cancer activities in silico without causing hemolysis. The peptide demonstrated stability under various conditions, including different pH levels, temperatures, salts, and metal ions (KCl and CaCl2), and remained stable in the presence of proteases such as trypsin and proteinase K at concentrations up to 0.2 µg/100 µl. The strong antibacterial efficacy and non-cytotoxic nature suggest that rCmDef is a single-edged sword that can contribute significantly to aquaculture disease management.

8.
Structure ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38889720

RESUMEN

Disulfide-rich peptides such as defensins play diverse roles in immunity and ion channel modulation, as well as constituting the bioactive components of many animal venoms. We investigated the structure and bioactivity of U-RDTX-Pp19, a peptide previously discovered in venom of the assassin bug Pristhesancus plagipennis. Recombinant Pp19 (rPp19) was found to possess insecticidal activity when injected into Drosophila melanogaster. A bioinformatic search revealed that domains homologous to Pp19 are produced by assassin bugs and diverse other arthropods. rPp19 co-eluted with native Pp19 isolated from P. plagipennis, which we found is more abundant in hemolymph than venom. We solved the three-dimensional structure of rPp19 using 2D 1H NMR spectroscopy, finding that it adopts a disulfide-stabilized structure highly similar to known trans-defensins, with the same cystine connectivity as human α-defensin (I-VI, II-IV, and III-V). The structure of Pp19 is unique among reported structures of arthropod peptides.

9.
Infection ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38856807

RESUMEN

PURPOSE: Ureaplasma urealyticum is a rare pathogen associated with septic arthritis that predominantly affects patients with hypogammaglobulinemia. Bacterial identification of fastidious organisms is challenging because they are undetectable by routine culture testing. To the best of our knowledge, this is the first report of septic arthritis induced by U. urealyticum infection in Japan. CASE DESCRIPTION: We describe the case of a 23-year-old Japanese female with secondary hypogammaglobulinemia (serum immunoglobulin level < 500 mg/dL), identified 8 years after treatment with rituximab. The patient presented with persistent fever and polyarthritis that were unresponsive to ceftriaxone and prednisolone. Contrast-enhanced computed tomography and gallium-67 scintigraphy revealed effusion and inflammation in the left sternoclavicular, hip, wrist, knee, and ankle joints. Although Gram staining and bacterial culture of the drainage fluid from the left hip joint were negative, the condition exhibited characteristics of purulent bacterial infection. The patient underwent empirical treatment with doxycycline, and her symptoms promptly resolved. Subsequent 16S ribosomal RNA (rRNA) gene sequencing of the joint fluid confirmed the presence of U. urealyticum, leading to the diagnosis of septic arthritis. Combination therapy with doxycycline and azithromycin yielded a favorable recovery from the inflammatory status and severe arthritic pain. CONCLUSION: This case highlights U. urealyticum as a potential causative agent of disseminated septic arthritis, particularly in patients with hypogammaglobulinaemia. The 16S rRNA gene analysis proved beneficial for identifying pathogens in culture-negative specimens, such as synovial fluid, in suspected bacterial infections.

10.
SICOT J ; 10: 24, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38847648

RESUMEN

BACKGROUND: Periprosthetic joint infection (PJI) remains a major complication following total joint arthroplasties (TJA), significantly affecting patient outcomes and healthcare costs. Despite advances in diagnostic techniques, challenges persist in accurately diagnosing PJI, underscoring the need for effective point-of-care testing (POCT). METHODS: This review examines the current literature and latest developments in POCT for diagnosing PJI, focusing on biomarkers such as alpha-defensin, leukocyte esterase, calprotectin, and C-reactive protein (CRP). Criteria from various societies like the Musculoskeletal Infection Society, Infectious Diseases Society of America, and the International Consensus Meeting were compared to evaluate the effectiveness of these biomarkers in a point-of-care setting. RESULTS: POCT provides rapid results essential for the timely management of PJI, with alpha-defensin and leukocyte esterase showing high specificity and sensitivity. Recent advancements have introduced novel biomarkers like calprotectin, which demonstrate high diagnostic accuracy. However, challenges such as the variability in test performance and the need for validation under different clinical scenarios remain. DISCUSSION: While POCT for PJI shows promising results, their integration into clinical practice requires standardized protocols and further validation. The evolution of these diagnostic tools offers a potential shift toward more personalized and immediate care, potentially improving outcomes for patients undergoing TJA.

11.
J Nutr ; 154(7): 2244-2254, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38795745

RESUMEN

BACKGROUND: Gut dysbiosis and increased intestinal permeability have been reported to precede type 1 diabetes-related autoimmunity. The role of gut inflammation in autoimmunity is not understood. OBJECTIVES: This study aimed to assess whether gut inflammation markers are associated with risk of islet autoimmunity and whether diet is associated with gut inflammation markers. METHODS: A nested case-control sample of 75 case children with islet autoimmunity and 88 control children was acquired from the Finnish Type 1 Diabetes Prediction and Prevention cohort. Diet was assessed with 3-d food records, and calprotectin and human ß-defensin-2 (HBD-2) were analyzed from stool samples at 6 and 12 mo of age. Conditional logistic regression analysis was used in a matched case-control setting to assess risk of autoimmunity. Analysis of variance, independent samples t test, and a general linear model were used in secondary analyses to test associations of background characteristics and dietary factors with inflammation markers. RESULTS: In unadjusted analyses, calprotectin was not associated with risk of islet autoimmunity, whereas HBD-2 in the middle (odds ratio [OR]: 3.23; 95% confidence interval [CI]: 1.03, 10.08) or highest tertile (OR: 3.02; 95% CI: 1.05, 8.69) in comparison to the lowest at 12 mo of age showed borderline association (P-trend = 0.063) with higher risk of islet autoimmunity. Excluding children with cow milk allergy in sensitivity analyses strengthened the association of HBD-2 with islet autoimmunity, whereas adjusting for dietary factors and maternal education weakened it. At age 12 mo, higher fat intake was associated with higher HBD-2 (ß: 0.219; 95% CI: 0.110, 0.328) and higher intake of dietary fiber (ß: -0.294; 95% CI: -0.510, -0.078), magnesium (ß: -0.036; 95% CI: -0.059, -0.014), and potassium (ß: -0.003; 95% CI: -0.005, -0.001) with lower HBD-2. CONCLUSIONS: Higher HBD-2 in infancy may be associated with higher risk of islet autoimmunity. Dietary factors play a role in gut inflammatory status.


Asunto(s)
Autoinmunidad , Biomarcadores , Diabetes Mellitus Tipo 1 , Dieta , Islotes Pancreáticos , Complejo de Antígeno L1 de Leucocito , beta-Defensinas , Humanos , Estudios de Casos y Controles , Finlandia , Femenino , Masculino , Complejo de Antígeno L1 de Leucocito/análisis , Diabetes Mellitus Tipo 1/inmunología , Lactante , Islotes Pancreáticos/inmunología , Factores de Riesgo , Inflamación , Heces/química
12.
Life Sci ; 349: 122740, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38777302

RESUMEN

Defensins are a class of small antimicrobial peptides that play a crucial role against pathogens. However, recent research has highlighted defensins exhibit the ability to influence cell cycle checkpoints, promoting or inhibiting specific phases such as G1 arrest or S/M transition. By regulating the cell cycle, defensins impact the proliferation of normal and cancerous cells, with implications for cancer development and progression. Dysregulation of defensin expression can disrupt the delicate balance of cell cycle regulation, leading to uncontrolled cell growth and an increased risk of tumor formation. Defensins contribute to the resolution of inflammation, stimulate angiogenesis, and enhance the migration and proliferation of cells involved in tissue repair. Furthermore, The ability of defensins to respond to microenvironmental changes further demonstrates the significance of these peptides in host defense mechanisms and immune function. By adjusting their expression, defensins continue to combat pathogens effectively and maintain homeostasis within the body. This review highlights the multifaceted role of defensins in regulating the cell cycle and their broader implications in cancer progression, tissue repair, and microenvironmental response.


Asunto(s)
Ciclo Celular , Proliferación Celular , Defensinas , Neoplasias , Humanos , Defensinas/metabolismo , Animales , Neoplasias/patología , Neoplasias/metabolismo , División Celular
13.
J Cell Biochem ; 125(7): e30576, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38726711

RESUMEN

Gingival epithelial cells (GECs) are physical and immunological barriers against outward pathogens while coping with a plethora of non-pathogenic commensal bacteria. GECs express several members of Toll-like receptors (TLRs) and control subsequent innate immune responses. TLR4 senses lipopolysaccharide (LPS) while TLR7/8 recognizes single-strand RNA (ssRNA) playing important roles against viral infection. However, their distinct roles in GECs have not been fully demonstrated. Here, we analyzed biological responses of GECs to  LPS and CL075, a TLR7/8 agonist. GE1, a mouse gingival epithelial cell line, constitutively express TLR4 and TLR7, but not TLR8, like primary skin keratinocytes. Stimulation of GE1 cells with CL075 induced cytokine, chemokine, and antimicrobial peptide  expressions, the pattern of which is rather different from that with LPS: higher mRNA levels of interferon (IFN) ß, CXCL10, and ß-defensin (BD) 14 (mouse homolog of human BD3); lower levels of tumor necrosis factor (TNF), CCL5, CCL11, CCL20, CXCL2, and CX3CL1. As for the intracellular signal transduction of GE1 cells, CL075 rapidly induced significant AKT phosphorylation but failed to activate IKKα/ß-NFκB pathway, whereas LPS induced marked IKKα/ß-NFκB activation without significant AKT phosphorylation. In contrast, both CL075 and LPS induced rapid IKKα/ß-NFκB activation and AKT phosphorylation in a macrophage cell line. Furthermore, specific inhibition of AKT activity abrogated CL075-induced IFNß, CXCL10, and BD14 mRNA expression in GE1 cells. Thus, TLR4/7 ligands appear to induce rather different host-defense responses of GECs through distinct intracellular signaling mechanisms.


Asunto(s)
Células Epiteliales , Encía , Lipopolisacáridos , Receptor Toll-Like 4 , Receptor Toll-Like 7 , Ratones , Animales , Encía/citología , Encía/metabolismo , Células Epiteliales/metabolismo , Células Epiteliales/inmunología , Receptor Toll-Like 4/metabolismo , Receptor Toll-Like 7/metabolismo , Lipopolisacáridos/farmacología , Transducción de Señal , Línea Celular , Inmunidad Innata , Glicoproteínas de Membrana/metabolismo , Humanos , Sulfonamidas
14.
Microb Pathog ; 192: 106691, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38759933

RESUMEN

Necrotic enteritis (NE) is a potentially fatal poultry disease that causes enormous economic losses in the poultry industry worldwide. The study aimed to evaluate the effects of dietary organic yeast-derived selenium (Se) on immune protection against experimental necrotic enteritis (NE) in commercial broilers. Chickens were fed basal diets supplemented with different Se levels (0.25, 0.50, and 1.00 Se mg/kg). To induce NE, Clostridium perfringens (C. perfringens) was orally administered at 14 days of age post hatch. The results showed that birds fed 0.25 Se mg/kg exhibited significantly increased body weight gain compared with the non-supplemented/infected birds. There were no significant differences in gut lesions between the Se-supplemented groups and the non-supplemented group. The antibody levels against α-toxin and NetB toxin increased with the increase between 0.25 Se mg/kg and 0.50 Se mg/kg. In the jejunal scrapings and spleen, the Se-supplementation groups up-regulated the transcripts for pro-inflammatory cytokines IL-1ß, IL-6, IL-8, iNOS, and LITAF and avian ß-defensin 6, 8, and 13 (AvBD6, 8 and 13). In conclusion, supplementation with organic yeast-derived Se alleviates the negative consequences and provides beneficial protection against experimental NE.


Asunto(s)
Alimentación Animal , Pollos , Infecciones por Clostridium , Clostridium perfringens , Citocinas , Suplementos Dietéticos , Enteritis , Enfermedades de las Aves de Corral , Selenio , Animales , Enteritis/prevención & control , Enteritis/veterinaria , Enteritis/inmunología , Enteritis/microbiología , Selenio/farmacología , Selenio/administración & dosificación , Enfermedades de las Aves de Corral/prevención & control , Enfermedades de las Aves de Corral/inmunología , Clostridium perfringens/inmunología , Infecciones por Clostridium/prevención & control , Infecciones por Clostridium/veterinaria , Infecciones por Clostridium/inmunología , Citocinas/metabolismo , Toxinas Bacterianas/inmunología , Necrosis , beta-Defensinas/metabolismo , Yeyuno/efectos de los fármacos , Yeyuno/inmunología , Yeyuno/microbiología , Yeyuno/patología , Bazo/inmunología , Levaduras , Óxido Nítrico Sintasa de Tipo II/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Interleucina-1beta/metabolismo , Anticuerpos Antibacterianos/sangre
15.
Artículo en Inglés | MEDLINE | ID: mdl-38763171

RESUMEN

BACKGROUND: Celery root is known to cause severe allergic reactions in patients sensitized to mugwort pollen. OBJECTIVE: We studied clinically well-characterized patients with celery allergy by IgE testing with a comprehensive panel of celery allergens to disentangle the molecular basis of what is known as the celery-mugwort syndrome. METHODS: Patients with suspected food allergy to celery underwent a standardized interview. Main inclusion criteria were a positive food challenge with celery or an unambiguous case history of severe anaphylaxis. IgE to celery allergens (rApi g 1.01, rApi g 1.02, rApi g 2, rApi g 4, nApi g 5, rApi g 6, rApi g 7) and to mugwort allergens (rArt v 1, rArt v 3, rArt v 4) were determined. IgE levels ≥0.35 kUA/L were regarded positive. RESULTS: Seventy-nine patients with allergy to celery were included. Thirty patients had mild oral or rhinoconjunctival symptoms, and 49 had systemic reactions. Sixty-eight percent had IgE to celery extract, 80% to birch pollen, and 77% to mugwort pollen. A combination of Api g 1.01, 1.02, 4, 5, and 7 increased the diagnostic sensitivity for celery allergy to 92%. The lipid transfer proteins Api g 2 and Api g 6 were not relevant in our celery-allergic population. IgE to Api g 7, detected in 52% of patients, correlated closely (r = 0.86) to Art v 1 from mugwort pollen. Eleven of 12 patients with monosensitization to Api g 7 were IgE negative to celery extract. The odds ratio for developing a severe anaphylactic reaction rather than only mild oral symptoms was about 6 times greater (odds ratio, 5.87; 95% confidence interval, 1.08-32.0; P = .0410) for Api g 7-sensitized versus -nonsensitized subjects. CONCLUSION: There is an urgent need for routine diagnostic tests to assess sensitization to Api g 7, not only to increase test sensitivity but also to identify patients at risk of a severe allergic reaction to celery.

16.
Dev Comp Immunol ; 158: 105207, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38797458

RESUMEN

Defensins are antimicrobial peptides involved in innate immunity, and gene number differs amongst eutherian mammals. Few studies have investigated defensins in marsupials, despite their potential involvement in immunological protection of altricial young. Here we use recently sequenced marsupial genomes and transcriptomes to annotate defensins in nine species across the marsupial family tree. We characterised 35 alpha and 286 beta defensins; gene number differed between species, although Dasyuromorphs had the largest repertoire. Defensins were encoded in three gene clusters within the genome, syntenic to eutherians, and were expressed in the pouch and mammary gland. Marsupial beta defensins were closely related to eutherians, however marsupial alpha defensins were more divergent. We identified marsupial orthologs of human DEFB3 and 6, and several marsupial-specific beta defensin lineages which may have novel functions. Marsupial predicted mature peptides were highly variable in length and sequence composition. We propose candidate peptides for future testing to elucidate the function of marsupial defensins.


Asunto(s)
Marsupiales , Filogenia , beta-Defensinas , Animales , Marsupiales/genética , Marsupiales/inmunología , beta-Defensinas/genética , beta-Defensinas/metabolismo , Humanos , Familia de Multigenes , Inmunidad Innata/genética , Defensinas/genética , Defensinas/metabolismo , Transcriptoma , Genoma , alfa-Defensinas/genética , alfa-Defensinas/metabolismo , Secuencia de Aminoácidos , Evolución Molecular
17.
Cell Commun Signal ; 22(1): 267, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38745232

RESUMEN

Low sperm motility is a significant contributor to male infertility. beta-defensins have been implicated in host defence and the acquisition of sperm motility; however, the regulatory mechanisms governing their gene expression patterns and functions remain poorly understood. In this study, we performed single-cell RNA and spatial transcriptome sequencing to investigate the cellular composition of testicular and epididymal tissues and examined their gene expression characteristics. In the epididymis, we found that epididymal epithelial cells display a region specificity of gene expression in different epididymal segments, including the beta-defensin family genes. In particular, Defb15, Defb18, Defb20, Defb25 and Defb48 are specific to the caput; Defb22, Defb23 and Defb26 to the corpus; Defb2 and Defb9 to the cauda of the epididymis. To confirm this, we performed mRNA fluorescence in situ hybridisation (FISH) targeting certain exon region of beta-defensin genes, and found some of their expression matched the sequencing results and displayed a close connection with epididimosome marker gene Cd63. In addition, we paid attention to the Sertoli cells and Leydig cells in the testis, along with fibroblasts and smooth muscle cells in the epididymis, by demonstrating their gene expression profile and spatial information. Our study provides a single-cell and spatial landscape for analysing the gene expression characteristics of testicular and epididymal environments and has important implications for the study of spermatogenesis and sperm maturation.


Asunto(s)
Epidídimo , Análisis de la Célula Individual , Maduración del Esperma , Transcriptoma , beta-Defensinas , Masculino , Animales , beta-Defensinas/genética , beta-Defensinas/metabolismo , Ratones , Transcriptoma/genética , Maduración del Esperma/genética , Epidídimo/metabolismo , Espermatozoides/metabolismo , Familia de Multigenes , Ratones Endogámicos C57BL , Testículo/metabolismo
18.
Reprod Biol ; 24(2): 100887, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38688100

RESUMEN

Human ß-defensins and interleukins may be auxiliary in sperm maturation. This cross-sectional study aimed to evaluate the expression of Human ß-defensins 1 and 2, interleukins (ILs)- 10 and -18 genes in sperm, as well as seminal plasma levels of these two cytokines in subfertile men with different types of sperm abnormalities compared to those with normozoospermic men. Participants were separated into two experimental groups: the control group (n = 25) and the group with sperm abnormalities (SA) (n = 45). SA participants were further subdivided into the following groups with n = 15 individuals each: Teratozoospermia (T), Asthenoteratozoospermia (AT), and Oligoasthenoteratozoospermia (OAT) groups. The quantitative real-time polymerase chain reaction was used to quantify the mRNA levels of hBDs 1 and 2, IL-10, and IL-18 in sperm. The seminal plasma concentrations of IL-10 and IL-18 were measured by using the enzyme-linked immunosorbent assay technique. The mRNA expression of hBD-1 and IL-10 showed a significant decrease in the OAT compared to the controls (P < 0.0001 and P = 0.02, respectively). The lowest seminal plasma concentration of IL-10 belonged to the OAT (P = 0.04). ROC curve analysis showed a sensitivity, specificity, and cutoff value of 82.35%, 86.67%, and 0.63 for hBD-1 levels, respectively. A positive and significant correlation was found between hBD-1 expression and sperm motility and IL-10 expression rate and normal sperm morphology.Therefore, hBD-1 could be considered as the alternative biomaterial to pre-treatments of infertile men with abnormal sperm parameters, specifically OAT men, which led to improving the assisted reproduction success rate.


Asunto(s)
Infertilidad Masculina , Motilidad Espermática , Espermatozoides , beta-Defensinas , Humanos , Masculino , beta-Defensinas/metabolismo , beta-Defensinas/genética , Infertilidad Masculina/metabolismo , Adulto , Espermatozoides/metabolismo , Estudios Transversales , Semen/metabolismo , Interleucina-10/metabolismo
19.
Heliyon ; 10(8): e29542, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38628749

RESUMEN

Objective: Today, designing nanofibers with antibacterial properties using electrospinning technology is one of the attractive approaches for wound healing. Methods: & analysis: This study aims to fabricate a nanocomposite from polyethylene oxide (PEO) coated with copper nanoparticles (NPs) and defensin peptide with wound healing and antimicrobial properties in different ratios of CuNPs/defensin (2/0 mg), (1.5/0.5 mg), and (1/1 mg) in the fixed contain polymer (98 mg). Then, the nanofiber properties were investigated by SEM, tensile, DSC, and BET analysis. Also, the antibacterial properties against S. aureus and E. coli, antioxidant, and in-vivo wound healing effects and histological analysis of the designed nanocomposites were evaluated in rat models. Results: Our SEM images showed that CuNPs and defensin were properly coated on the PEO surface. According to the tensile, DSC, and antibacterial analysis results, the most appropriate feature was related to CuNPs/defensin (1.5/0.5 mg), with maximum elasticity, heat resistance, and antibacterial activity. Furthermore, the designed nanocomposites showed the best performance as a wound closure agent by increasing dermis and epidermis volume density, stimulating fibroblast cells and collagen fiber production, and improving skin vessels. Conclusion: According to our results, PEO nanofibers loaded with CuNPs and defensin have the best potential for wound healing, and they can be used as antibacterial materials in the textile, drug, and medical industries.

20.
JEADV Clin Pract ; 3(1): 150-159, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38646149

RESUMEN

Background: Beta-defensins (BDs) are antimicrobial peptides secreted upon epithelial injury. Both chemotactic and antimicrobial properties of BDs function as initial steps in host defense and prime the adaptive immune system in the body. Psoriasis, a chronic immune-mediated inflammatory disease, has both visible cutaneous manifestations as well as known associations with higher incidence of cardiometabolic complications and vascular inflammation. Objectives: We aimed to investigate the circulating expression of beta-defensin-2 (BD2) in psoriasis at baseline compared to control subjects, along with changes in BD2 levels following biologic treatment at one-year. The contribution of BD2 to subclinical atherosclerosis is also assessed. In addition, we have sought to unravel signaling mechanisms linking inflammation with BD2 expression. Methods: Multimodality imaging as well inflammatory biomarker assays were performed in biologic naïve psoriasis (n=71) and non-psoriasis (n=53) subjects. A subset of psoriasis patients were followed for one-year after biological intervention (anti-Tumor Necrosis Factor-α (TNFα), n=30; anti-Interleukin17A (IL17A), n=21). Measurements of circulating BD2 were completed by Enzyme-Linked Immunosorbent Assay (ELISA). Using HaCaT transformed keratinocytes, expression of BD2 upon cytokine treatment was assessed by quantitative polymerase chain reaction (qPCR) and ELISA. Results: Herein, we confirm that human circulating BD2 levels associate with psoriasis, which attenuate upon biologic interventions (anti-TNFα, anti-IL-17A). A link between circulating BD2 and sub-clinical atherosclerosis markers was not observed. Furthermore, we demonstrate that IL-17A-driven BD2 expression occurs in a Phosphatidylinositol 3-kinase (PI3-kinase) and Rac1 GTPase-dependent manner. Conclusions: Our findings expand on the potential role of BD2 as a tractable biomarker in psoriasis patients and describes the role of an IL-17A-PI3-kinase/Rac signaling axis in regulating BD2 levels in keratinocytes.

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