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1.
PLoS One ; 19(5): e0300747, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38696378

RESUMEN

We investigate the impact of left-behind experiences on the urban identity of new-generation migrant workers using data from the 2017 China Migrants Dynamic Survey. The results show the following: (1) The left-behind experience is an important factor undermining the urban identity of new-generation migrant workers, and the conclusion remains consistent after robustness checks, such as propensity score matching. (2) Left-behind experiences of both parents away from home had the most significant negative impact on urban identity. (3) The results of the mechanism tests indicate that the left-behind experience exerts an adverse impact on urban identity through the pathways of poorer physical health, more frequent migration, more challenging job search, and stronger dependence on preexisting social networks. The findings of this study also offer policy suggestions for promoting the urban identity of new-generation migrant workers.


Asunto(s)
Migrantes , Población Urbana , Humanos , Migrantes/psicología , Masculino , China , Adulto , Femenino , Encuestas y Cuestionarios , Adulto Joven , Persona de Mediana Edad
2.
Am J Transplant ; 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38514014

RESUMEN

Highly inflamed and neovascularized corneal graft beds are known as high-risk (HR) environments for transplant survival. One of the primary factors leading to this rejection is reduction in the suppressive function of regulatory T cells (Treg). Our results show that myeloid-derived suppressor cells (MDSC) counteract interleukin-6-mediated Treg dysfunction by expressing interleukin-10. Additionally, MDSC maintain forkhead box P3 stability and their ability to suppress IFN-γ+ Th1 cells. Administering MDSC to HR corneal transplant recipients demonstrates prolonged graft survival via promotion of Treg while concurrently suppressing IFN-γ+ Th1 cells. Moreover, MDSC-mediated donor-specific immune tolerance leads to long-term corneal graft survival as evidenced by the higher survival rate or delayed survival of a second-party C57BL/7 (B6) graft compared to those of third-party C3H grafts observed in contralateral low-risk or HR corneal transplantation of BALB/c recipient mice, respectively. Our study provides compelling preliminary evidence demonstrating the effectiveness of MDSC in preventing Treg dysfunction, significantly improving graft survival in HR corneal transplantation, and showing promising potential for immune tolerance induction.

3.
J Thromb Haemost ; 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38537781

RESUMEN

BACKGROUND: Megakaryocytes (MKs) are polyploid cells responsible for producing ∼1011 platelets daily in humans. Unraveling the mechanisms regulating megakaryopoiesis holds the promise for the production of clinical-grade platelets from stem cells, overcoming significant current limitations in platelet transfusion medicine. Previous work identified that loss of the epigenetic regulator SET domain containing 2 (SETD2) was associated with an increased platelet count in mice. However, the role of SETD2 in megakaryopoiesis remains unknown. OBJECTIVES: Here, we examined how SETD2 regulated MK development and platelet production using complementary murine and human systems. METHODS: We manipulated the expression of SETD2 in multiple in vitro and ex vivo models to assess the ploidy of MKs and the function of platelets. RESULTS: The genetic ablation of Setd2 increased the number of high-ploidy bone marrow MKs. Peripheral platelet counts in Setd2 knockout mice were significantly increased ∼2-fold, and platelets exhibited normal size, morphology, and function. By knocking down and overexpressing SETD2 in ex vivo human cell systems, we demonstrated that SETD2 negatively regulated MK polyploidization by controlling methylation of α-tubulin, microtubule polymerization, and MK nuclear division. Small-molecule inactivation of SETD2 significantly increased the production of high-ploidy MKs and platelets from human-induced pluripotent stem cells and cord blood CD34+ cells. CONCLUSION: These findings identify a previously unrecognized role for SETD2 in regulating megakaryopoiesis and highlight the potential of targeting SETD2 to increase platelet production from human cells for transfusion practices.

4.
Exp Eye Res ; 242: 109871, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38527580

RESUMEN

Myeloid derived suppressor cells (MDSCs) are a heterogenous population of immature hematopoietic precursors with known immunoregulatory functions. The immunosuppressive role of MDSCs has been highlighted in several inflammatory ophthalmic disorders; however, their therapeutic application in suppressing the immune-mediated changes in dry eye disease (DED) has not been studied. We observed significant reduction in antigen presenting cell (APC) frequencies and their maturation in the presence of MDSCs. Moreover, co-culturing MDSCs with T helper 17 cells (Th17) resulted in reduced Th17 frequencies and their IL-17 expression. On the contrary, MDSCs maintained regulatory T cell frequencies and enhanced their function in-vitro. Furthermore, we delineated the role of interleukin-10 (IL-10) secreted by MDSCs in their immunoregulatory functions. We confirmed these results by flow cytometry analysis and observed that treatment with MDSCs in DED mice effectively suppressed the maturation of APCs, pathogenic Th17 response, and maintained Treg function and significantly ameliorated the disease. The results in this study highlight the potential therapeutic application of MDSCs in treating refractory DED.


Asunto(s)
Modelos Animales de Enfermedad , Síndromes de Ojo Seco , Citometría de Flujo , Ratones Endogámicos C57BL , Células Supresoras de Origen Mieloide , Linfocitos T Reguladores , Células Th17 , Animales , Células Supresoras de Origen Mieloide/inmunología , Síndromes de Ojo Seco/inmunología , Síndromes de Ojo Seco/metabolismo , Ratones , Células Th17/inmunología , Linfocitos T Reguladores/inmunología , Células Presentadoras de Antígenos/inmunología , Femenino , Progresión de la Enfermedad , Interleucina-10/metabolismo , Células Cultivadas , Técnicas de Cocultivo
5.
Biomolecules ; 14(2)2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38397406

RESUMEN

Alpha-melanocyte-stimulating hormone (α-MSH) and its binding receptors (the melanocortin receptors) play important roles in maintaining ocular tissue integrity and immune homeostasis. Particularly extensive studies have demonstrated the biological functions of α-MSH in both immunoregulation and cyto-protection. This review summarizes the current knowledge of both the physiological and pathological roles of α-MSH and its receptors in the eye. We focus on recent developments in the biology of α-MSH and the relevant clinical implications in treating ocular diseases.


Asunto(s)
Melanocortinas , alfa-MSH , Humanos , alfa-MSH/farmacología , alfa-MSH/metabolismo , Receptores de Melanocortina/metabolismo , Inflamación/tratamiento farmacológico , Muerte Celular
6.
Cells ; 13(4)2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38391935

RESUMEN

Macrophages play a crucial role in the innate immune response, serving as key effector cells in the defense against pathogens. Although the role of the large-conductance voltage and calcium-activated potassium channel, also known as the KCa1.1 or BK channel, in regulating neurotransmitter release and smooth muscle contraction is well known, its potential involvement in immune regulation remains unclear. We employed BK-knockout macrophages and noted that the absence of a BK channel promotes the polarization of macrophages towards a pro-inflammatory phenotype known as M1 macrophages. Specifically, the absence of the BK channel resulted in a significant increase in the secretion of the pro-inflammatory cytokine IL-6 and enhanced the activity of extracellular signal-regulated kinases 1 and 2 (Erk1/2 kinases), Ca2+/calmodulin-dependent protein kinase II (CaMKII), and the transcription factor ATF-1 within M1 macrophages. Additionally, the lack of the BK channel promoted the activation of the AIM2 inflammasome without affecting the activation of the NLRC4 and NLRP3 inflammasomes. To further investigate the role of the BK channel in regulating AIM2 inflammasome activation, we utilized BK channel inhibitors, such as paxilline and iberiotoxin, along with the BK channel activator NS-11021. Pharmacological inactivation of the BK channel increased, and its stimulation inhibited IL-1ß production following AIM2 inflammasome activation in wild-type macrophages. Moreover, wild-type macrophages displayed increased calcium influx when activated with the AIM2 inflammasome, whereas BK-knockout macrophages did not due to the impaired extracellular calcium influx upon activation. Furthermore, under conditions of a calcium-free medium, IL-1ß production following AIM2 inflammasome activation was increased in both wild-type and BK-knockout macrophages. This suggests that the BK channel is required for the influx of extracellular calcium in macrophages, thus limiting AIM2 inflammasome activation. In summary, our study reveals a regulatory role of the BK channel in macrophages under inflammatory conditions.


Asunto(s)
Inflamasomas , Canales de Potasio de Gran Conductancia Activados por el Calcio , Inflamasomas/metabolismo , Canales de Potasio de Gran Conductancia Activados por el Calcio/metabolismo , Calcio/metabolismo , Macrófagos/metabolismo , Inmunidad Innata , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo
7.
Front Pharmacol ; 14: 1270787, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38034997

RESUMEN

Aims: Myocardial ischemia-reperfusion (I/R) injury markedly undermines the protective benefits of revascularization, contributing to ventricular dysfunction and mortality. Due to complex mechanisms, no efficient ways exist to prevent cardiomyocyte reperfusion damage. Vagus nerve stimulation (VNS) appears as a potential therapeutic intervention to alleviate myocardial I/R injury. Hence, this meta-analysis intends to elucidate the potential cellular and molecular mechanisms underpinning the beneficial impact of VNS, along with its prospective clinical implications. Methods and Results: A literature search of MEDLINE, PubMed, Embase, and Cochrane Database yielded 10 articles that satisfied the inclusion criteria. VNS was significantly correlated with a reduced infarct size following myocardial I/R injury [Weighed mean difference (WMD): 25.24, 95% confidence interval (CI): 32.24 to 18.23, p < 0.001] when compared to the control group. Despite high heterogeneity (I2 = 95.3%, p < 0.001), sensitivity and subgroup analyses corroborated the robust efficacy of VNS in limiting infarct expansion. Moreover, meta-regression failed to identify significant influences of pre-specified covariates (i.e., stimulation type or site, VNS duration, condition, and species) on the primary estimates. Notably, VNS considerably impeded ventricular remodeling and cardiac dysfunction, as evidenced by improved left ventricular ejection fraction (LVEF) (WMD: 10.12, 95% CI: 4.28; 15.97, p = 0.001) and end-diastolic pressure (EDP) (WMD: 5.79, 95% CI: 9.84; -1.74, p = 0.005) during the reperfusion phase. Conclusion: VNS offers a protective role against myocardial I/R injury and emerges as a promising therapeutic strategy for future clinical application.

8.
Exp Eye Res ; 236: 109657, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37722586

RESUMEN

Exposure to mustard agents, such as sulfur mustard (SM) and nitrogen mustard (NM), often results in ocular surface damage. This can lead to the emergence of various corneal disorders that are collectively referred to as mustard gas keratopathy (MGK). In this study, we aimed to develop a mouse model of MGK by using ocular NM exposure, and describe the subsequent structural changes analyzed across the different layers of the cornea. A 3 µL solution of 0.25 mg/mL or 5 mg/mL NM was applied to the center of the cornea via a 2-mm filter paper for 5 min. Mice were evaluated prior to and after exposure on days 1, 3, 7, 14, and 28 for 4 weeks using slit lamp examination with fluorescein staining. Anterior segment optical coherence tomography (AS-OCT) and in vivo confocal microscopy (IVCM) tracked changes in the epithelium, stroma, and endothelium of the cornea. Histologic evaluation was used to examine corneal cross-sections collected at the completion of follow-up. Following exposure, mice experienced central corneal epithelial erosion and thinning, accompanied by a decreased number of nerve branches in the subbasal plexus and increased activated keratocytes in the stroma in both dosages. The epithelium was recovered by day 3 in the low dose group, followed by exacerbated punctuate erosions alongside persistent corneal edema that arose and continued onward to four weeks post-exposure. The high dose group showed persistent epitheliopathy throughout the study. The endothelial cell density was reduced, more prominent in the high dose group, early after NM exposure, which persisted until the end of follow-up, along with increased polymegethism and pleomorphism. Microstructural changes in the central cornea at 4 weeks post-exposure included dysmorphic basal epithelial cells and reduced epithelial thickness, and in the limbal cornea included decreased cellular layers. We present a mouse model of MGK using NM that successfully replicates ocular injury caused by SM in humans who have been exposed to mustard gas.


Asunto(s)
Enfermedades de la Córnea , Edema Corneal , Úlcera de la Córnea , Gas Mostaza , Humanos , Animales , Ratones , Gas Mostaza/toxicidad , Mecloretamina/toxicidad , Córnea/patología , Enfermedades de la Córnea/inducido químicamente , Enfermedades de la Córnea/patología , Úlcera de la Córnea/patología , Trastornos de la Visión/patología , Microscopía Confocal
9.
J Med Internet Res ; 25: e46092, 2023 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-37494107

RESUMEN

BACKGROUND: Telephone-assisted cardiopulmonary resuscitation (T-CPR) has proven to be a crucial intervention in enhancing the ability of lay responders to perform cardiopulmonary resuscitation (CPR) during telehealth emergency services. While the majority of established T-CPR protocols primarily focus on guiding individual rescuers, there is a lack of emphasis on instructing and coordinating multiple lay responders to perform resuscitation collaboratively. OBJECTIVE: This study aimed to develop an innovative team-based tele-instruction tool to efficiently organize and instruct multiple lay responders on the CPR process and to evaluate the effectiveness and feasibility of the tool. METHODS: We used a mixed methods design in this study. We conducted a randomized controlled simulation trial to conduct the quantitative analysis. The intervention groups used the team-based tele-instruction tool for team resuscitation, while the control groups did not have access to the tool. Baseline resuscitation was performed during the initial phase (phase I test). Subsequently, all teams watched a team-based CPR education training video and finished a 3-person practice session with teaching followed by a posttraining test (phase II test). In the qualitative analysis, we randomly selected an individual from each team and 4 experts in emergency medical services to conduct semistructured interviews. The purpose of these interviews was to evaluate the effectiveness and feasibility of this tool. RESULTS: The team-based tele-instruction tool significantly improved the quality of chest compression in both phase I and phase II tests. The average compression rates were more appropriate in the intervention groups compared to the control groups (median 104.5, IQR 98.8-111.8 min-1 vs median 112, IQR 106-120.8 min-1; P=.04 in phase I and median 117.5, IQR 112.3-125 min-1 vs median 111, IQR 105.3-119 min-1; P=.03 in phase II). In the intervention group, there was a delay in the emergency response time compared to that in the control group (time to first chest compression: median 20, IQR 15-24.8 seconds vs median 25, IQR 20.5-40.3 seconds; P=.03; time to open the airway: median 48, IQR 36.3-62 seconds vs median 73.5, IQR 54.5-227.8 seconds; P=.01). However, this delay was partially mitigated after the phase II test. The qualitative results confirmed the compatibility and generalizability of the team-based tele-instruction tool, demonstrating its ability to effectively guide multiple lay responders through teamwork and effective communication with telecommunicators. CONCLUSIONS: The use of the team-based tele-instruction tool offers an effective solution to enhance the quality of chest compression among multiple lay responders. This tool facilitated the organization of resuscitation teams by dispatchers and enabled efficient cooperation. Further assessment of the widespread adoption and practical application of the team-based tele-instruction tools in real-life rescue scenarios within the telehealth emergency services system is warranted.


Asunto(s)
Reanimación Cardiopulmonar , Servicios Médicos de Urgencia , Telemedicina , Humanos , Reanimación Cardiopulmonar/educación , Teléfono
10.
Int J Cardiovasc Imaging ; 39(9): 1667-1675, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37233916

RESUMEN

PURPOSE: In most clinical trials, intracardiac echocardiography (ICE) has provided fewer views than the four standard views provided by transesophageal echocardiography (TEE) when assessing left atrial appendage closure (LAAC) devices. This study aimed to determine if ICE guided by the CartoSound system achieve adequate high-quality views and similar clinical outcomes as TEE during LAAC. METHODS: This study prospectively enrolled 202 patients who underwent LAAC using either ICE (n = 69), TEE (n = 121), or a combination of ICE and TEE (n = 12) as the procedural imaging under local anesthesia. A novel multi-angled "FLAVOR" approach was used for assessment in the ICE group. RESULTS: ICE allowed visualization of the implanted devices in all patients at all proposed angles with long-axis views while two-dimensional (2D) TEE showed short-axis views in 1 or 2 angles in 24.2% of cases, which was more prevalent when the pulmonary ridge was covered by the occluder. In the combined ICE-TEE cohort, 2D-TEE failed to detect peri-device leak in 1 patient. The complication rates were similar between the ICE and TEE groups. Shorter fluoroscopy time, lower radiation dose and contrast usage were founded in the ICE group. At first TEE follow-up, the rate and degree of peri-device leak were similar between the ICE and TEE groups. CONCLUSION: A systematic ICE protocol using a CartoSound module to guide LAAC was reliable for comprehensive long-axis imaging assessment compared with 2D/3D TEE under local anesthesia with a shorter fluoroscopy time, lower radiation dose, and less use of contrast.


Asunto(s)
Apéndice Atrial , Fibrilación Atrial , Humanos , Ecocardiografía Transesofágica , Apéndice Atrial/diagnóstico por imagen , Resultado del Tratamiento , Fibrilación Atrial/diagnóstico por imagen , Fibrilación Atrial/cirugía , Cateterismo Cardíaco , Valor Predictivo de las Pruebas , Ecocardiografía/métodos
11.
Am J Transplant ; 23(9): 1345-1358, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37245642

RESUMEN

Corneal transplantation is the most common form of solid tissue grafting, with an approximately 80% to 90% success rate. However, success rates may decline when donor tissues are derived from patients with a history of diabetes mellitus (DM). To evaluate the underlying immunopathologic processes that cause graft rejection, we used streptozotocin-induced type 1 DM (DM1) and transgenic Lepob/ob type 2 DM (DM2) diabetic murine models as donors and nondiabetic BALB/c as recipients. DM resulted in an increased frequency of corneal antigen-presenting cells (APCs) with an acquired immunostimulatory phenotype. Following transplantation, recipients that received either type of diabetic graft showed increased APC migration and T helper type 1 alloreactive cells, impaired functional regulatory T cells, and graft survival. Insulin treatment in streptozotocin-induced diabetic mice led to an increased tolerogenic profile of graft APC, lower T helper type 1 sensitization, and a higher frequency of functional regulatory T cells with high suppressive capacity, reflected in increased graft survival. We conclude that both DM1 and DM2 in donors can impact corneal APC functional phenotype, rendering the tissue more immunogenic and thereby increasing the risk of graft failure.


Asunto(s)
Trasplante de Córnea , Diabetes Mellitus Experimental , Animales , Ratones , Diabetes Mellitus Experimental/cirugía , Diabetes Mellitus Experimental/patología , Estreptozocina , Córnea , Células Presentadoras de Antígenos
12.
Exp Eye Res ; : 109495, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37142048

RESUMEN

Exposure to mustard agents, such as sulfur mustard (SM) and nitrogen mustard (NM), often results in ocular surface damage. This can lead to the emergence of various corneal disorders that are collectively referred to as mustard gas keratopathy (MGK). In this study, we aimed to develop a mouse model of MGK by using ocular NM exposure, and describe the subsequent structural changes analyzed across the different layers of the cornea. A 3 µL solution of 0.25 mg/mL NM was applied to the center of the cornea via a 2-mm filter paper for 5 min. Mice were evaluated prior to and after exposure on days 1 and 3, and weekly for 4 weeks using slit lamp examination with fluorescein staining. Anterior segment optical coherence tomography (AS-OCT) and in vivo confocal microscopy (IVCM) tracked changes in the epithelium, stroma, and endothelium of the cornea. Histologic evaluation and immunostaining were used to examine corneal cross-sections collected at the completion of follow-up. A biphasic ocular injury was observed in mice exposed to NM, most prominent in the corneal epithelium and anterior stroma. Following exposure, mice experienced central corneal epithelial erosions and thinning, accompanied by a decreased number of nerve branches in the subbasal plexus and increased activated keratocytes in the stroma. The epithelium was recovered by day 3, followed by exacerbated punctuate erosions alongside persistent stromal edema that arose and continued onward to four weeks post-exposure. The endothelial cell density was reduced on the first day after NM exposure, which persisted until the end of follow-up, along with increased polymegethism and pleomorphism. Microstructural changes in the central cornea at this time included dysmorphic basal epithelial cells, and in the limbal cornea included decreased cellular layers and p63+ area, along with increased DNA oxidization. We present a mouse model of MGK using NM that successfully replicates ocular injury caused by SM in humans who have been exposed to mustard gas. Our research suggests DNA oxidation contributes to the long-term effects of nitrogen mustard on limbal stem cells.

13.
FASEB J ; 37(4): e22855, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36906286

RESUMEN

Chronic uveitis comprises heterogeneous clinical entities characterized by sustained and recurrent intraocular inflammation that is believed to be driven by autoimmune responses. The management of chronic uveitis is challenging with the limited availability of efficacious treatments, and the underlying mechanisms mediating disease chronicity remain poorly understood as the majority of experimental data are derived from the acute phase of the disease (the first 2-3 weeks post-induction). Herein, we investigated the key cellular mechanisms underlying chronic intraocular inflammation using our recently established murine model of chronic autoimmune uveitis. We demonstrate unique long-lived CD44hi IL-7R+ IL-15R+ CD4+ memory T cells in both retina and secondary lymphoid organs after 3 months postinduction of autoimmune uveitis. These memory T cells functionally exhibit antigen-specific proliferation and activation in response to retinal peptide stimulation in vitro. Critically, these effector-memory T cells are capable of effectively trafficking to the retina and accumulating in the local tissues secreting both IL-17 and IFN-γ upon adoptively transferred, leading to retinal structural and functional damage. Thus, our data reveal the critical uveitogenic functions of memory CD4+ T cells in sustaining chronic intraocular inflammation, suggesting that memory T cells can be a novel and promising therapeutic target for treating chronic uveitis in future translational studies.


Asunto(s)
Enfermedades Autoinmunes , Enfermedades de la Retina , Uveítis , Ratones , Humanos , Animales , Modelos Animales de Enfermedad , Linfocitos T CD4-Positivos , Inflamación
14.
J Clin Med ; 12(3)2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36769499

RESUMEN

The optimal antithrombotic strategy after percutaneous left atrial appendage closure (LAAC) has not yet been established. The advisability of administering low-dose direct oral anticoagulation after LAAC to patients at high risk of bleeding is uncertain. Thus, in the present study, we evaluated the safety and effectiveness of reduced-(15 mg) or half-dose rivaroxaban (10 mg) versus warfarin regarding real-world risks of thromboembolism, bleeding, and device-related thrombosis (DRT) after LAAC. Patients with non-valvular atrial fibrillation and HASBLED ≥ 3 who had undergone successful LAAC device implantation from October 2014 to April 2020 were screened and those who had received 10 mg or 15 mg rivaroxaban or warfarin therapy were enrolled. The patients were followed up 45 days and 6 months after LAAC to evaluate outcomes, including death, thromboembolism, major bleeding, and DRT. Of 457 patients with HASBLED ≥ 3 who had undergone LAAC, 115 had received warfarin and 342 rivaroxaban (15 mg: N = 164; 10 mg: N = 178). There were no significant differences in the incidence of thromboembolism or DRT between the warfarin and both doses of rivaroxaban groups (all p > 0.05). The incidence of major bleeding was significantly higher in the warfarin group than in either the reduced- or half-dose rivaroxaban groups (warfarin vs. rivaroxaban 15 mg: 2.6% vs. 0%, p = 0.030; warfarin vs. rivaroxaban 10 mg: 2.6% vs. 0%, p = 0.038). Either reduced- or half-dose rivaroxaban may be an effective and safe alternative to warfarin therapy in patients with LAAC and who are at high risk of bleeding, the risk of thromboembolism being similar and of major bleeding lower for both doses of rivaroxaban.

15.
Mucosal Immunol ; 16(5): 711-726, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36642378

RESUMEN

Corneal transplant rejection primarily occurs because of the T helper 1 (Th1) effector cell-mediated immune response of the host towards allogeneic tissue. The evidence suggests that type 1 migratory conventional CD103+ dendritic cells (CD103+DC1) acquire an immunosuppressive phenotype in the tumor environment; however, the involvement of CD103+DC1 in allograft survival continues to be an elusive question of great clinical significance in tissue transplantation. In this study, we assess the role of CD103+DC1 in suppressing Th1 alloreactivity against transplanted corneal allografts. The immunosuppressive function of CD103+DC1 has been extensively studied in non-transplantation settings. We found that host CD103+DC1 infiltrates the corneal graft and migrates to the draining lymph nodes to suppress alloreactive CD4+ Th1 cells via the programmed death-ligand 1 axis. The systemic depletion of CD103+ DC1 in allograft recipients leads to amplified Th1 activation, impaired Treg function, and increased rate of allograft rejection. Although allograft recipient Rag1 null mice reconstituted with naïve CD4+CD25- T cells efficiently generated peripheral Treg cells (pTreg), the CD103+DC1-depleted mice failed to generate pTreg. Furthermore, adoptive transfer of pTreg failed to rescue allografts in CD103+DC1-depleted recipients from rejection. These data demonstrate the critical role of CD103+DC1 in regulating host alloimmune responses.

16.
Transplantation ; 107(6): 1302-1310, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36584368

RESUMEN

BACKGROUND: Corneal transplantation outcomes are generally less favorable in young children compared with adults. The purpose of this study was to determine the immunological mechanisms underlying this difference. METHODS: A murine model of allogeneic corneal transplantation was used in the study, and graft survival was determined by evaluating opacity scores for 8 wk. Syngeneic transplantation in the very young host served as a surgical control. The frequencies of total and activated natural killer (NK) cells in cornea posttransplantation were kinetically evaluated using flow cytometry. The regulatory T cell (Treg) frequency and function in naive animals were assessed by flow cytometry and in vitro suppression assays, respectively. Finally, graft survival and immune responses were determined in NK cell-depleted, or adult naive Treg-transferred, young hosts. RESULTS: Corneal allograft survival in the very young recipients was significantly lower than in adult hosts. The frequencies of total NK cells and their interferon gamma-expressing subset in the cornea were significantly higher in the very young mice posttransplantation. In ungrafted mice, frequencies of Treg in draining lymph nodes as well as their capabilities to suppress NK-cell secretion of interferon gamma were lower in the very young compared with adults. In NK cell-depleted or adult Treg--transferred very young recipients, the allograft survival was significantly improved along with the suppressed NK-cell response. CONCLUSIONS: Our data demonstrate that amplified activity of NK cells, together with lower suppressive function of Treg, contributes to early rejection of corneal allografts in very young graft recipients.


Asunto(s)
Trasplante de Córnea , Linfocitos T Reguladores , Ratones , Animales , Interferón gamma , Córnea , Células Asesinas Naturales , Rechazo de Injerto , Ratones Endogámicos C57BL , Ratones Endogámicos BALB C
17.
Gene ; 851: 147010, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36349576

RESUMEN

Copy number variation (CNV), as one of the important variations in the biological genome, refers to the deletion and duplication of genomic segments between 1 kb and 50 kb caused by genomic rearrangements. Currently, many copy number variations have been found to be significantly associated with important economic traits such as growth, development and reproduction of cattle. However, the study of MUC19 gene has not been reported. In this study, we detected an appropriate correlation between MUC19 gene and growth traits of Chinese cattle. We detected the distribution of MUC19-CNV across Qinchuan cattle (QC), Pinan cattle (PN), Xianan cattle (XN), Yunling cattle (YL), Guyuan cattle (GY), Jiaxian cattle (JX), and analyzed the association between types of MUC19-CNV and growth traits through SPSS20.0 software and method of ANOVA. The results showed that various types of CNV were present in each breed of cattle, but there were discrepancies in the distribution of copy number variant types. The Association analysis result showed that CNV of MUC19 gene showed a postive effect in cattle growth traits: the copy number of MUC19 was significantly correlated with hip width of PN cattle (P < 0.01), height at hip cross and withers height of PN cattle (P < 0.05), hip width and body length of JX cattle (P < 0.05), Huckle bone width of YL cattle (P < 0.05).


Asunto(s)
Variaciones en el Número de Copia de ADN , Polimorfismo de Nucleótido Simple , Bovinos/genética , Animales , Variaciones en el Número de Copia de ADN/genética , Fenotipo , Genoma , China
18.
Aging Dis ; 13(5): 1391-1404, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36186141

RESUMEN

Alzheimer's disease (AD) is the most common form of neurodegenerative disease. The predominant characteristics of AD are the accumulation of amyloid-ß (Aß) and hyperphosphorylated tau in the brain. Blood brain barrier (BBB) dysfunction as one of the causative factors of cognitive impairment is increasingly recognized in the last decades. However, the role of BBB dysfunction in AD pathogenesis is still not fully understood. It remains elusive whether BBB dysfunction is a consequence or causative fact of Aß pathology, tau pathology, neuroinflammation, or other conditions. In this review, we summarized the major findings of BBB dysfunction in AD and the reciprocal relationships between BBB dysfunction, Aß pathology, tau pathology, and neuroinflammation. In addition, the implications of BBB dysfunction in AD for delivering therapeutic drugs were presented. Finally, we discussed how to better determine the underlying mechanisms between BBB dysfunction and AD, as well as how to explore new therapies for BBB regulation to treat AD in the future.

19.
Ocul Surf ; 26: 184-190, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36067981

RESUMEN

PURPOSE: Allergic conjunctivitis is the most common cause leading to ocular redness (OR). Herein, using an animal model of allergic OR, we evaluated the therapeutic efficacy of topical blockade of substance P (SP) in treating red eye. METHODS: Allergic OR was induced in guinea pigs with topical histamine. Ocular SP was blocked using a specific SP receptor (neurokinin-1 receptor, NK1R) antagonist, L-703,606, via topical application 10 min before or 10 min after histamine instillation. Animal eyes were examined and a series of images were taken for up to 60 min post-OR induction. The severity of redness was analyzed using the quantitative ocular redness index (ORI). At the end of clinical examination, conjunctival tissues were collected for histological examination of conjunctival blood vessels and infiltrating eosinophils and neutrophils. In addition, SP concentration was quantified in the tear fluid and expression levels of inflammatory cytokines were assessed in the conjunctival tissues. RESULTS: Topical histamine application successfully induced red eye, evidenced by the significantly increased ORI during the observation period, with peak values at 10 min, along with significantly increased levels of SP in the tears. Topical treatment with L-703,606, either before histamine application or at the time of peak ORI, effectively reduced ORI and suppressed conjunctival blood vessel dilation, along with decreased eosinophil and neutrophil infiltration, and inflammatory cytokine expression in the conjunctiva, as well as reduced SP levels in the tears. CONCLUSIONS: Topical blockade of SP effectively prevents and treats allergy-related ocular redness by suppressing blood vessel dilation and allergic inflammation.


Asunto(s)
Conjuntivitis Alérgica , Sustancia P , Cobayas , Animales , Histamina/farmacología , Histamina/uso terapéutico , Conjuntivitis Alérgica/tratamiento farmacológico , Conjuntivitis Alérgica/etiología , Conjuntiva/patología , Eosinófilos/metabolismo , Eosinófilos/patología
20.
Curr Pharm Des ; 28(28): 2349-2361, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35927923

RESUMEN

OBJECTIVE: We explored circadian clock-related genes (CCRG) to establish a risk model and identify associations with the tumor immune microenvironment in cutaneous melanoma (CM). METHODS: Circadian clock genes were downloaded from Circadian Gene Database. To explore CM-related circadian clock genes, we combined multivariate cox regression associated with least absolute shrinkage and selection operator (LASSO) regression in the Cancer Genome Atlas (TCGA) and validated it in the GSE65904 dataset. Time-dependent receiver operating characteristic curve (ROC) and Kaplan-Meier analysis were calculated to determine a CCRG risk score model. In addition, the overall survival nomograms of clinicopathological factors and circadian clock-related gene signatures. Additionally, we evaluated the connection between circadian clock-related genes with immune checkpoint inhibitors and immune cell infiltration. RESULTS: Two circadian clock-related signatures were established. The risk model included SEMA4D (p<0.001, HR: 0.709, 95% CI: 0.581 to 0.867) and SOD-2 (p=0.009, HR: 0.790, 95% CI: 0.663 to 0.944) in patients with TCGA melanoma. The risk model was based on two CCRGs enriched in base excision repair, glycosylphosphatidyl (GPI), and one carbon of the folate pathway. The overall survival was lower in the high-risk group. In addition, the circadian-clock signature may be able to evaluate the immunotherapy response. CONCLUSIONS: We developed and validated a circadian signature to characterize the clinical significance and tumor microenvironment of cutaneous melanoma, revealing that circadian rhythms may impact cutaneous melanoma.


Asunto(s)
Relojes Circadianos , Melanoma , Neoplasias Cutáneas , Biomarcadores de Tumor/genética , Carbono , Relojes Circadianos/genética , Ácido Fólico , Regulación Neoplásica de la Expresión Génica , Humanos , Inhibidores de Puntos de Control Inmunológico , Melanoma/genética , Melanoma/patología , Pronóstico , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Microambiente Tumoral/genética , Melanoma Cutáneo Maligno
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