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1.
Reprod Biomed Online ; 49(1): 103940, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38744030

RESUMO

RESEARCH QUESTION: Cryopreservation of ovarian tissue is one feasible option to preserve female fertility prior to cancer treatment. The slow freezing protocol represents the current standard approach, while vitrification has been suggested as a promising alternative. This paper reports the follow-up and first successful delivery after retransplantation of vitrified, rapid warmed ovarian tissue in Europe. DESIGN: After the patient received a diagnosis of breast cancer, ovarian tissue was removed laparoscopically and sent via overnight transportation to University Hospital Bonn for vitrification on site. The patient was treated with chemotherapy, leading to ovarian failure. After 2 years, retransplantation of the vitrified, rapid warmed tissue was conducted on site. RESULTS: Two months after grafting, the patient reported regular menstrual cycles. After 1 further month a clinical pregnancy occurred, which ended in a spontaneous abortion at the 8th week of pregnancy. Six months after grafting, another naturally conceived pregnancy was determined, resulting in the birth of a healthy boy 14 months after retransplantation of the ovarian tissue. CONCLUSIONS: Complementing the successful deliveries reported by the groups of Suzuki (Japan) and Silber (USA) regarding vitrified tissue, the current results confirm the high potential of this cryopreservation method in a clinical routine setting as an alternative approach to the widespread slow freezing method.

2.
Sci Rep ; 14(1): 3287, 2024 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-38332226

RESUMO

Cryopreservation and reimplantation of human ovarian tissue restore the ovarian hormonal function and fertility due to the preservation of follicles. As the success depends on proper angiogenesis, different approaches aim to support this process. In mice, pretreatment of ovarian tissue with FSH shows increased follicular numbers probably due to the supported angiogenesis by an increased vascular endothelial factor (VEGF) expression. However, in human tissue it remains completely unclear, which effect the hormonal status of the patient has at the time point of reimplantation. Frozen-thawed human ovarian cortical tissue was cultured for 48 h with 0, 1 or 10 ng/mL recombinant human FSH. VEGF-A expression was assessed by ELISA and immunohistofluorescence (IHF) analysis. By IHF, HIF-1α and FSHR expression dependency on culture and FSH concentration was analyzed. Follicles at all stages expressed VEGF-A, which increases during folliculogenesis. Frozen-thawed human ovarian cortical tissue secreted a not statistically different amount of VEGF-A, when cultured in presence of 1 ng/mL FSH (17.5 mIU/mL). However, the presence of 10 ng/mL FSH (175 mIU/mL) significantly decreased VEGF-A expression and secretion. The high FSH concentration increased especially the VEGF-A expression of already growing follicles. The presence of pre-menopausal concentrations of FSH had no significant effect on VEGF-A expression, whereas the presence of elevated FSH levels decreased cortical VEGF-A expression. A hormonal pre-treatment of women with elevated FSH concentrations prior to reimplantation might be considered to support angiogenesis. Here, we show that VEGF-A expression by follicles is affected by FSH dependent on the concentration.


Assuntos
Hormônio Foliculoestimulante , Fator A de Crescimento do Endotélio Vascular , Humanos , Feminino , Camundongos , Animais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Hormônio Foliculoestimulante/farmacologia , Hormônio Foliculoestimulante/metabolismo , Ovário/metabolismo , Folículo Ovariano/metabolismo , Criopreservação
3.
Sci Rep ; 13(1): 12885, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37558708

RESUMO

Vitrification of ovarian tissue is a promising alternative approach to the traditional slow freezing method. Few empirical investigations have been conducted to determine the angiogenic profiles of these two freezing methods. In this study we aimed to answer the question whether one of the cryopreservation methods should be preferred based on the secretion of angiogenic factors. Tissue culture with reduced oxygen (5%) was conducted for 48 h with samples of fresh, slow frozen/thawed and vitrified/rapid warmed ovarian cortex tissue from 20 patients. From each patient, tissue was used in all three treatment groups. Tissue culture supernatants were determined regarding cytokine expression profiles of angiogenin, angiopoietin-2, epidermal growth factor, basic fibroblast growth factor, heparin binding epidermal growth factor, hepatocyte growth factor, Leptin, Platelet-derived growth factor B, placental growth factor and vascular endothelial growth factor A via fluoroimmunoassay. Apoptotic changes were assessed by TUNEL staining of cryosections and supplemented by hematoxylin and eosin and proliferating cell nuclear antigen staining. Comparing the angiogenic expression profiles of vitrified/rapid warmed tissue with slow frozen/thawed tissue samples, no significant differences were observed. Detection of apoptotic DNA fragmentation via TUNEL indicated minor apoptotic profiles that were not significantly different comparing both cryopreservation methods. Vitrification of ovarian cortical tissue does not appear to impact negatively on the expression profile of angiogenic factors and may be regarded as an effective alternative approach to the traditional slow freezing method.


Assuntos
Criopreservação , Fator A de Crescimento do Endotélio Vascular , Humanos , Feminino , Congelamento , Fator de Crescimento Placentário , Criopreservação/métodos , Vitrificação
4.
Reprod Biomed Online ; 47(3): 103239, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37400319

RESUMO

RESEARCH QUESTION: What are the parameters of age, indications for ovarian tissue cryopreservation, storage characteristics and reasons for tissue disposal in a large cohort of individuals undertaking cryopreservation? DESIGN: The relevant parameters in a single university centre were revised and digitalized in the period from 2019 to 2021. To assess patients' motivation at the end of storage, patients were contacted by letter, e-mails and telephone calls. RESULTS: A group of 2475 patients with stored ovarian tissue were analysed in the time period between 2000 and 2021; the response rate for contact calls and letters was 28.8% (224/777). Where storage had ended (n = 1155), patients had on average stored for 3.8 years and begun storing at age 30 years; the main indications were breast cancer (53%) and lymphoma (17.5%). Of these participants, 2.5% had a transplantation on site, 10.3% transferred their tissue to another cryobank and 11.5% were deceased. The majority of the group (75.7%) ended their storage due to pregnancy (49.1%), a lack of desire to have children (25.9%), storage fees that were too expensive (8.9%), death (8.5%), recurrence of cancer (8.5%), lack of a partner (4%) and fear of surgery in the future (3.1%); 6.7% retrospectively regretted ending storage. CONCLUSIONS: The pregnancy rate of 49.1%, resulting from ovarian tissue that was not removed during surgery for scheduled ovarian tissue cryopreservation supports the clinical approach of removing and cryopreserving only 25-50% of one ovary. It is proposed that interdisciplinary counselling should be implemented not only prior to fertility preservation, but also when intending to end storage.


Assuntos
Neoplasias da Mama , Preservação da Fertilidade , Gravidez , Criança , Feminino , Humanos , Adulto , Ovário/patologia , Estudos Retrospectivos , Preservação da Fertilidade/métodos , Criopreservação/métodos , Neoplasias da Mama/patologia
5.
Life (Basel) ; 13(5)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37240742

RESUMO

Due to a vast influx in the secretory phase of the menstrual cycle, leukocytes represent 40-50% of the decidua at the time of implantation. Their importance for the implantation, maintenance of pregnancy, and parturition are known yet not fully understood. Thus, in idiopathic infertility, decidual immune-related factors are speculated to be the cause. In this review, the immune cell functions in the decidua were summarized, and clinical diagnostics, as well as interventions, were discussed. There is a rising number of commercially available diagnostic tools. However, the intervention options are still limited and/or poorly studied. In order for us to make big steps towards the proper use of reproductive immunology findings, we need to understand the mechanisms and especially support translational research.

6.
Arch Gynecol Obstet ; 307(2): 591-599, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36175682

RESUMO

BACKGROUND: The standard procedure most frequently used for ovarian tissue cryopreservation (OTC) is slow freezing, while vitrification has been proposed as promising alternative and has built an impressive catalog of success in fertility laboratories regarding cryopreservation of oocytes and embryos. METHODS: We developed and evaluated a high-throughput protocol for vitrification of human ovarian tissue suitable for clinical processing. Follicular viability was assessed via calcein staining prior and after cryopreservation analyzing ovarian tissue of a cohort of 30 patients. RESULTS: We found no significant differences regarding follicular viability between slow frozen and vitrified cortex tissue samples 24 h after thawing and rapid warming. Follicular viability of thawed and rapid warmed samples was not significantly different in comparison to fresh samples, indicating high proportions of follicular survival rates with both methods. CONCLUSIONS: High-throughput vitrification is a promising option in a clinical setting. More research is required to determine the status of other tissue-specific quality indicators potentially influencing on autotransplantation.


Assuntos
Ovário , Vitrificação , Feminino , Humanos , Congelamento , Criopreservação/métodos , Oócitos
7.
Mol Hum Reprod ; 28(12)2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36342218

RESUMO

Within the options available for fertility preservation, cryopreservation of ovarian cortical tissue has become an important technique. Freezing and thawing procedures have been optimized to preserve tissue integrity and viability. However, the improvement of the tissue retransplantation is currently of great interest. Rapid angiogenesis is needed at the retransplantation site to accomplish sufficient blood supply to provide oxygen and nutrients. Many studies address this issue. However, we need to understand the physiology of the thawed tissue to gain further understanding of the complexities of the procedure. As freezing and thawing generally impairs cellular metabolism, we aimed to characterize the changes in metabolic activity and secretion of the angiogenic factor vascular endothelial growth factor-A (VEGF-A) of frozen-thawed ovarian cortical tissue over time. Biopsy punches of ovarian cortical tissue from patients undergoing fertility preservation were maintained in culture without freezing or after a slow-freezing and thawing procedure. VEGF-A secretion was measured after 48 h by ELISA. To examine temporary changes, metabolic activity was assessed for both fresh and frozen-thawed tissue of the same patient. Metabolic activity and VEGF-A secretion were measured at 0, 24 and 48 h in culture. Thawed ovarian cortical tissue secreted significantly less VEGF-A compared to fresh ovarian cortical tissue within 48 h of culture. After thawing, metabolic activity was significantly reduced compared to fresh ovarian cortex but over the course of 48 h, the metabolic activity recovered. Similarly, VEGF-A secretion of thawed tissue increased significantly over 48 h. Here, we have shown that it takes 48 h for ovarian cortical tissue to recover metabolically after thawing, including VEGF-A secretion.


Assuntos
Preservação da Fertilidade , Fator A de Crescimento do Endotélio Vascular , Feminino , Humanos , Congelamento , Criopreservação/métodos , Preservação da Fertilidade/métodos , Ovário
8.
Reprod Biol Endocrinol ; 20(1): 109, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35906658

RESUMO

Early pregnancy is marked by placentation and embryogenesis, which take place under physiological low oxygen concentrations. This oxygen condition is crucial for many aspects of placentation, trophoblast function, vascularization and immune function. Recently, a new family of innate lymphoid cells has been found to be expressed at the fetomaternal interface. Among these, type 3 innate lymphoid cells (ILC3) are important antigen presenting cells in the context of MHC-II. The expression of MHC-II on ILC3s during pregnancy is reduced. We tested the hypothesis that low oxygen concentrations reduce the potential of ILC3s to present antigens promoting fetal tolerance.Using an in vitro approach, NCR+ ILC3s generated from cord blood stem cell precursors were incubated under different O2 concentrations in the presence or absence of the pregnancy-related hormones hCG and TGF-ß1. The expression of MHC-II, accessory molecules and an activation marker were assessed by flow cytometry. We observed that 1% O2 reduced the expression of the MHC-II molecule HLA-DR as compared to 21% O2 and modulated the relative effects of hCG and TGF-ß1.Our data indicate that low oxygen concentrations reduce the antigen presentation potential of NCR+ ILC3s and suggest that it may promote fetal tolerance during the first trimester of pregnancy.


Assuntos
Apresentação de Antígeno , Linfócitos , Feminino , Hormônios/metabolismo , Humanos , Imunidade Inata , Linfócitos/metabolismo , Oxigênio/metabolismo , Oxigênio/farmacologia , Gravidez , Fator de Crescimento Transformador beta1/metabolismo
9.
Arch Gynecol Obstet ; 306(4): 1299-1311, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35871693

RESUMO

BACKGROUND: Despite its clinical success rates, transplantation after ovarian tissue cryopreservation (OTC) remains a matter of concern. Certain cancer subtypes may lead to the transfer of malignant cells when transplantation of affected ovarian tissue is conducted. IVG and subsequent isolation of vital follicles obtained from frozen thawed ovarian tissue for further in vitro maturation (IVM) would expand current fertility protection techniques while reducing the risk of retransplanting malignant cells. METHODS: A total of 216 cortical biopsies from 3 patients were included in this study in 4 treatment groups. After freezing, thawing and 8 days of hypoxic tissue culture supplemented with different concentrations of human follicular fluid (HuFF) and follicle-stimulating hormone (FSH), follicles were isolated enzymatically and stained with calcein to determine follicular viability. Numbers and size of vital follicles were assessed by fluorescence microscopy (Ti2, Nikon) and specified by computer assisted, semi-automated measurement (NIS software, Nikon). To estimate the effect of in vitro culture on apoptosis, tissue sections were stained for nicked DNA (TUNEL) prior and after tissue culture. RESULTS: Analysing 3025 vital follicles, we observed significant differences [P < 0.01] regarding follicle size when hypoxic tissue culture was supplemented with HuFF compared with the control group on day 1, individual follicles reached sizes > 100 µm. CONCLUSIONS: The results implicate that HuFF contains valuable factors contributing to significant IVG of follicles in human ovarian tissue and could be regarded as an additional tool in personalized fertility restoration prior to retransplantation of ovarian tissue.


Assuntos
Líquido Folicular , Folículo Ovariano , Criopreservação , Feminino , Congelamento , Humanos , Ovário
10.
Front Immunol ; 12: 698045, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34531854

RESUMO

Pregnancy success depends greatly on a balanced immune homeostasis. The detection of bacterial components in the upper reproductive tract in non-pregnant and pregnant women raised questions on its possible beneficial role in reproductive health. The local conditions that allow the presence of bacteria to harmonize with the establishment of pregnancy are still unknown. Among the described bacterial species in endometrial and placental samples, Fusobacterium nucleatum was found. It has been observed that F. nucleatum can induce tumorigenesis in colon carcinoma, a process that shares several features with embryo implantation. We propose that low concentrations of F. nucleatum may improve trophoblast function without exerting destructive responses. Inactivated F. nucleatum and E. coli were incubated with the trophoblastic cell lines HTR8/SVneo, BeWo, and JEG-3. Viability, proliferation, migratory capacity, invasiveness and the secretion of chemokines, other cytokines and matrix metalloproteinases were assessed. The presence of F. nucleatum significantly induced HTR8/SVneo invasion, accompanied by the secretion of soluble mediators (CXCL1, IL-6 and IL-8) and metalloproteinases (MMP-2 and MMP-9). However, as concentrations of F. nucleatum increased, these did not improve invasiveness, hindered migration, reduced cell viability and induced alterations in the cell cycle. Part of the F. nucleatum effects on cytokine release were reverted with the addition of a TLR4 blocking antibody. Other effects correlated with the level of expression of E-cadherin on the different cell lines tested. Low amounts of F. nucleatum promote invasion of HTR8/SVneo cells and induce the secretion of important mediators for pregnancy establishment. Some effects were independent of LPS and correlated with the expression of E-cadherin on trophoblasts.


Assuntos
Fusobacterium nucleatum , Gravidez , Trofoblastos , Linhagem Celular , Feminino , Humanos , Técnicas In Vitro
11.
Reproduction ; 160(1): 155-169, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32130203

RESUMO

Strategically located in mucosal barriers, innate lymphoid cells (ILCs) are relevant in local containment and tolerance of commensal microflora. ILCs have been recently described at the fetomaternal interface, where the development of a semi-allogeneic fetus can only succeed in a well-controlled immune environment. We postulate that ILCs adapt their antigen presentation capacity to protect pregnancy from excessive immune responses. Human ILCs were studied in deciduae of term pregnancies, peripheral blood and in in vitro generated ILCs. Fresh isolated lymphocytes or cells treated with pregnancy-related factors were investigated. The fetal antigen rejection-based CBA/J × DBA/2J mouse model (poor outcome pregnant mice; POPM) was used to characterize ILC antigen presentation potential in normal and immunologically disturbed pregnancies. ILC antigen presentation potential was characterized by flow cytometry and qPCR. We discovered that the distribution of ILC subsets changed during both human and murine pregnancy. Moreover, the pregnancy was accompanied by reduced MHCII expression in splenic ILCs during normal pregnancy (CBA/J × BALB/c; good outcome pregnant mice; GOPM) but increased in splenic and intestinal ILCs of CBA/J × DBA/2J mice. In vitro, splenic ILCs from pregnant mice increased MHCII expression after stimulation with IL-1ß and IL-23. In contrast, uterine ILCs displayed lower MHCII expression, which remained unchanged after stimulation. Finally, pregnancy-related factors and hormones present in the uterine environment reduced antigen presentation potential of human ILCs in vitro. Together, these data indicate that, during pregnancy, peripheral and especially uterine ILCs adapt their antigen presenting potential to maintain a level of tolerance and support pregnancy.


Assuntos
Apresentação de Antígeno/imunologia , Feto/imunologia , Hormônios/farmacologia , Tolerância Imunológica/imunologia , Imunidade Inata/imunologia , Linfócitos/imunologia , Animais , Apresentação de Antígeno/efeitos dos fármacos , Feminino , Feto/efeitos dos fármacos , Humanos , Tolerância Imunológica/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos CBA , Camundongos Endogâmicos DBA , Gravidez
12.
Anticancer Res ; 40(2): 841-846, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32014927

RESUMO

BACKGROUND: Cold atmospheric plasma (CAP) has a variety of anticancer effects on different cancer cell types. In osteosarcoma (OS) cells, CAP reduces growth and motility, induces apoptosis, and alters secretion of cellular factors. The influence of CAP on membrane integrity of OS cells is unknown. MATERIALS AND METHODS: Two different OS cell lines (U-2 OS and MNNG-HOS) were treated with CAP. Proliferation assays for cell growth after treatment was performed. Alterations in membrane permeability and the associated translocation of low molecular weight particles through the cytoplasmic membrane of OS cells after CAP treatment were shown in fluorescein diacetate (FDA) assays. RESULTS: FDA increasingly passed the membrane after CAP treatment and this effect depended on the duration of treatment. It was also shown that after CAP treatment, FDA was able to diffuse into the cells from the outside as well as out of the cell interior. These effects were observed when CAP-treated buffer was used and therefore no direct contact between cells and CAP occurred. CONCLUSION: The observations suggest that changes in membrane permeability and function may contribute to the antiproliferative effects of CAP.


Assuntos
Permeabilidade da Membrana Celular/efeitos dos fármacos , Osteossarcoma/tratamento farmacológico , Gases em Plasma/uso terapêutico , Linhagem Celular Tumoral , Humanos , Osteossarcoma/patologia , Gases em Plasma/farmacologia
13.
In Vivo ; 33(6): 1767-1771, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31662501

RESUMO

BACKGROUND/AIM: The structural integrity of the eukaryotic cytoplasmic membrane is of crucial importance for its cell biological function and thus for the survival of the cell. Physical and chemical noxae can interact in various ways with components of the cytoplasmic membrane, influence its permeability and thus mediate toxic effects. In the study presented, changes in membrane permeability were quantified by intracellular accumulation of a fluorescent dye and by the release of the fluorescent dye from dye-loaded cells. MATERIALS AND METHODS: Non-malignant (RC-124) and malignant (786-O, Caki-1) renal cells were permeabilized with different concentrations of Triton X-100. The permeability of the membrane was determined at the single-cell level by the uptake of the dye into the cell inner by flow cytometry. In addition, a fluorescence plate reader was used to detect and quantify the release of the dye into the cell culture supernatant. RESULTS: Both malignant and non-malignant cells showed a dose-dependent alteration of membrane permeability after treatment with Triton X-100. In the presence of the fluorescent dye, significantly more dye was introduced into the permeabilized cells compared to control incubations. Vice versa, Triton X-100-treated and dye-loaded cells released significantly more dye into the cell culture supernatant. CONCLUSION: The combination of measurement of intracellular accumulated and extracellular released dye can quantifiably detect changes in membrane permeability due to cell-membrane damage. The combination of two different measurement methods offers additional value in reliable detection of membrane-damaging, potentially toxic influences.


Assuntos
Permeabilidade da Membrana Celular/fisiologia , Membrana Celular/metabolismo , Fluoresceína/metabolismo , Rim/metabolismo , Linhagem Celular , Citoplasma/metabolismo , Citometria de Fluxo/métodos , Fluorescência , Corantes Fluorescentes/metabolismo , Humanos
14.
Reproduction ; 158(4): 323-333, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31426030

RESUMO

Alterations in the immunologic balance during pregnancy have been associated with poor pregnancy outcomes. The underlying mechanisms are complex and mouse models delivered valuable information on inflammatory imbalance in disturbed pregnancies and served as model to test potential anti-inflammatory therapies. CD83 is a transmembrane protein (mCD83) with a soluble form (sCD83) which possesses strong anti-inflammatory properties. During murine pregnancy, upregulated mCD83 expression induces sCD83 release after in vitro stimulation with LPS, phorbol myristate acetate (PMA) and ionomycin. The release mechanism of sCD83 and its control are yet to be elucidated. In this study, the expression of mCD83 and sCD83 has been extensively studied in the CBA/J × DBA/2J mouse model of pro-inflammatory-mediated pregnancy disturbances. mCD83 was higher expressed on splenic B cells, uterus-draining lymph nodes T cells and dendritic cells from mice with poor pregnancy outcome (PPOM) compared to mice with good pregnancy outcome (GPOM). PPOM, however, was accompanied by lower sCD83 serum levels. In vitro treatment of splenic B cells with progesterone led to a reduction of TIMP1 expression, mCD83 expression and sCD83 release, while TIMP1 treatment had a positive effect on sCD83 availability. These results suggest that tissue and matrix components are involved in the regulation of CD83 in murine pro-inflammatory pregnancies.


Assuntos
Antígenos CD/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Imunoglobulinas/metabolismo , Inflamação/fisiopatologia , Glicoproteínas de Membrana/metabolismo , Complicações na Gravidez/metabolismo , Animais , Antígenos CD/genética , Linfócitos B/imunologia , Linfócitos B/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Feminino , Imunoglobulinas/genética , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos CBA , Camundongos Endogâmicos DBA , Gravidez , Complicações na Gravidez/genética , Complicações na Gravidez/patologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Antígeno CD83
15.
Reprod Biol ; 19(2): 113-118, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31023521

RESUMO

Contrary to the traditional assumption of a sterile uterus, the number of studies characterizing microbial entities in the healthy upper reproductive tract (endometrial cavity, including follicular fluid and placenta) have been on the increase. Substantial data has been accumulated correlating microbial composition with fertility outcome. In this context, the presence of certain taxa was associated to an improved reproductive success. A summarization for the evidence of these molecular mechanisms through which bacteria may affect developmental processes during pregnancy is presented and discussed with special focus placed upon the immunological aspects.


Assuntos
Líquido Amniótico/microbiologia , Bactérias/isolamento & purificação , Microbiota , Placenta/microbiologia , Útero/microbiologia , Bactérias/classificação , Feminino , Humanos , Gravidez
16.
Sci Rep ; 7(1): 3923, 2017 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-28634388

RESUMO

Chlamydiae are bacterial pathogens that grow in vacuolar inclusions. Dendritic cells (DCs) disintegrate these compartments, thereby eliminating the microbes, through auto/xenophagy, which also promotes chlamydial antigen presentation via MHC I. Here, we show that TNF-α controls this pathway by driving cytosolic phospholipase (cPLA)2-mediated arachidonic acid (AA) production. AA then impairs mitochondrial function, which disturbs the development and integrity of these energy-dependent parasitic inclusions, while a simultaneous metabolic switch towards aerobic glycolysis promotes DC survival. Tubulin deacetylase/autophagy regulator HDAC6 associates with disintegrated inclusions, thereby further disrupting their subcellular localisation and stability. Bacterial remnants are decorated with defective mitochondria, mito-aggresomal structures, and components of the ubiquitin/autophagy machinery before they are degraded via mito-xenophagy. The mechanism depends on cytoprotective HSP25/27, the E3 ubiquitin ligase Parkin and HDAC6 and promotes chlamydial antigen generation for presentation on MHC I. We propose that this novel mito-xenophagic pathway linking innate and adaptive immunity is critical for effective DC-mediated anti-bacterial resistance.


Assuntos
Ácido Araquidônico/metabolismo , Chlamydia/crescimento & desenvolvimento , Células Dendríticas/citologia , Mitofagia , Fosfolipases A2 Citosólicas/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Linhagem Celular , Chlamydia/citologia , Técnicas de Cocultura , Células Dendríticas/metabolismo , Células Dendríticas/microbiologia , Glicólise , Desacetilase 6 de Histona/metabolismo , Camundongos , Viabilidade Microbiana , Linfócitos T/citologia , Linfócitos T/metabolismo
17.
FEBS Lett ; 590(21): 3920-3940, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27397851

RESUMO

Chlamydia psittaci causes psittacosis/ornithosis in birds and is an economically important pathogen for poultry farming. It also infects nonavian domestic animals as well as rodents, and is a zoonotic human pathogen responsible for atypical pneumonia. The bacterium efficiently disseminates in host organisms causing pulmonary and systemic disease. Its rapid entry, fast replication cycle, and tight control of intracellular transport routes contribute to the host-to-host transmission and efficient growth observed with C. psittaci. Recent studies have revealed that the pathogen copes better than other chlamydial strains with proinflammatory effectors produced during the early immune reaction of infected hosts. These features likely contribute to successful infections and might explain the potent adaptation and evasion characteristics of the agent. Current findings on cell-autonomous, innate, and adaptive defenses against C. psittaci provide novel insights into the concerted immune mechanisms involved in the clearance of the pathogen. Further in-depth studies on C. psittaci and other related agents in cellular as well as animal models are needed to develop more efficient antichlamydial therapies and vaccination strategies.


Assuntos
Chlamydophila psittaci/fisiologia , Chlamydophila psittaci/patogenicidade , Psitacose/transmissão , Adaptação Fisiológica , Animais , Chlamydophila psittaci/genética , Genoma Bacteriano , Interações Hospedeiro-Patógeno , Humanos , Evasão da Resposta Imune , Psitacose/imunologia , Psitacose/veterinária
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