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1.
Chinese Medical Ethics ; (6): 7-13, 2024.
Article in Chinese | WPRIM | ID: wpr-1012841

ABSTRACT

Human-animal chimera technology is increasingly applied to large animals. It is highly possible to cultivate human organs in pigs for transplantation in the future. Chimeric animals contain more and more human materials and are present in their brains and reproductive systems, which may humanize them and give them a higher moral status and even dignity. It raises an important ethical question: should such chimeric animals be created? If so, how they should be treated. It is not convincing to refute the research of human-animal chimera with the arguments of destroying natural order, unnatural and moral chaos. But the non-identity view holds that scientific research makes the lives of chimeric animals more valuable and that they are not actually harmed because their only other options do not exist. The answers to these ethical questions can resolve the ethical risks arising from the research of human-animal chimera.

2.
Journal of Experimental Hematology ; (6): 1921-1924, 2023.
Article in Chinese | WPRIM | ID: wpr-1010061

ABSTRACT

Proteolysis-targeting chimeras (PROTACs) are heterobifunctional small molecules by utilizing the ubiquitin proteasome system (UPS) to degrade proteins of interest. PROTACs have exhibited unprecedented efficacy and specificity in degrading various oncogenic proteins because of their unique mechanism of action, ability to target "undruggable" and mutant proteins. A series of PROTACs have been developed to degrade multiple key protein targets for the treatment of hematologic malignancy. Notably, PROTACs that target BCL-XL, IRAK4, STAT3 and BTK have entered clinical trials. The known PROTACs that have the potential to be used to treat various hematological malignancies are systematically summarized in this review.


Subject(s)
Humans , Hematologic Neoplasms/drug therapy , Proteasome Endopeptidase Complex/metabolism , Ubiquitin-Protein Ligases/metabolism , Proteolysis Targeting Chimera
3.
Chinese Journal of Biotechnology ; (12): 3615-3627, 2023.
Article in Chinese | WPRIM | ID: wpr-1007981

ABSTRACT

Proteolysis targeting chimera (PROTAC) refers to heterobifunctional small molecules that can simultaneously bind an E3 ubiquitin ligase and a target protein, enabling specific degradation of the target protein with the aid of the ubiquitin proteasome system. At present, most PROTAC drugs are in the clinical trial stage, and the ligands are mainly non-covalent compounds. PROTAC drugs have the advantage of overcoming drug resistance and degrading "undruggable" target proteins, but non-covalent ligands could lead to the hook effect that undermines drug efficacy. With its own advantages, covalent ligands can avoid the occurrence of this phenomenon, which is of great help to the development of PROTAC. This review summarizes the progress in preclinical and clinical research and application of PROTAC molecules targeting three different classes of protein targets, including intranuclear, transmembrane, and cytosolic proteins. We also offer perspective discussions to provide research ideas and references for the future development of PROTAC.


Subject(s)
Proteolysis , Proteolysis Targeting Chimera , Proteasome Endopeptidase Complex/metabolism , Ubiquitin-Protein Ligases/metabolism , Proteins/metabolism , Ligands
4.
China Pharmacy ; (12): 961-967, 2023.
Article in Chinese | WPRIM | ID: wpr-972268

ABSTRACT

OBJECTIVE To provide information service support for research on proteolysis targeting chimera (PROTAC) in China and provide reference for technical development and patent layout of relevant drug research and development institutions. METHODS The patent analysis method was used to search the patent applications related to PROTAC technology that had been applied to China National Intellectual Property Administration and had been issued before Feb. 2022, using the HimmPat patent database as the search platform. The patent application trend, technology life cycle, main applicants, technology source countries, technology themes, improvement routes and other patent data were analyzed. RESULTS & CONCLUSIONS A total of 133 patents were included in this study. The patent application for PROTAC technology started relatively late in China, with the number of applicants increasing from 2 in 2015 to 30 in 2020, and the number of applications increasing from 2 in 2015 to 38 in 2020. Both the annual patent application volume and the number of applicants were in a period of rapid growth, but the average annual application volume of a single applicant was still less than 2, indicating that research in this field was still in the early stage of technology development; the number of applications from Arvinas, Hisco, and Hinova Pharmaceutical Inc. ranked among the top. Although the number of domestic applications led that of foreign applications in China, the average number of simple peer applications and the average number of simple peer countries in domestic patent applications was only 1.5, which was far lower than that of foreign applications in China, reflecting that there was still room for improvement in the “quality” level of domestic applications. The initial improvements in PROTAC technology mainly focused on the selection of E3 ligands, targets and ligands, and then new improvements such as new PROTAC development, linker design and matching methods emerged, indicating that the patent applicant had started a multi-track layout in the early stages of the development of PROTAC technology. It is suggested that the research and development of PROTAC drugs in China should focus on improving the oral bioavailability and biosafety of PROTAC drugs, overcoming potential drug resistance, and exploring rational design and evaluation methods.

5.
Belo Horizonte; s.n; 2023. 124 p.
Thesis in Portuguese | LILACS | ID: biblio-1444992

ABSTRACT

As leishmanioses são doenças tropicais negligenciadas com alta endemicidade e que afetam milhares de pessoas no mundo. Sua infecção é causada por parasitos protozoários do gênero Leishmania. A diversidade biológica entre as espécies é quem permite determinar as manifestações clínicas, sendo elas na forma de leishmaniose visceral (LV) ou leishmaniose tegumentar (LT). Dentre estas manifestações, a LV é considerada a mais grave, devido sua alta letalidade e grande emergência em indivíduos com a infecção provocada pelo vírus da imunodeficiência humana (HIV). Atualmente, as medidas de controle e prevenção adotadas pela Organização Mundial da Saúde (OMS), baseiam-se em uma combinação de estratégias de intervenção contra a infecção, uma vez que o diagnóstico eficaz e precoce é indispensável para que se possa intervir com o tratamento adequado, diminuindo índices de mortalidade e a evolução de complicações clínicas. Entretanto, os testes sorológicos utilizados apresentam sensibilidade e especificidade prejudicadas em pacientes com leishmanioses e/ou coinfectados LV/HIV, devido a baixos ní-veis de anticorpos antileishmanial ou pela presença de doenças que causem reação cruzada, levando a resultados falso-positivos. A sensibilidade torna-se também variável em pacientes tratados, uma vez que a sorologia pode manter-se positiva por meses ou anos após o fim do tratamento e cura da doença. Buscando resolver tal problemática, a identificação de novos antígenos, por meio de análises de bioinformática associadas à imunoproteômica, tem permitido a detecção de novas proteínas com potencial aplicação diagnóstica. Em estudos anteriores, as proteínas hipotéticas LiHyT, LiHyD, LiHyV e LiHyP foram encontradas em espécies de Leishmania spp, e avaliadas em suas versões recombinantes por meio de ensaios de ELISA, obtendo resultados satisfatórios para a detecção da LV humana e canina. Com base nessas informações, o presente trabalho teve como objetivo desenvolver uma proteína quimera recombinante base-ada na predição de epítopos lineares específicos de células B das quatro proteínas antigênicas de L. infantum citadas e avaliar o potencial diagnóstico, assim como dos peptídeos individuais que a constituíram, frente à leishmaniose humana, bem como com a coinfecção com HIV, além de testar os antígenos como marcadores prognóstico após o tratamento da LV e LT. As sequências de aminoácidos das proteínas foram avaliadas e oito epítopos de células B foram preditos e utilizados na construção de uma nova proteína quimérica. A proteína foi expressa, purificada e avaliada como antígeno recombinante em ELISA para o diagnóstico de LV, LT, coinfecção LV/HIV e prognóstico em amostras de pacientes tratados de LV e LT. Os epítopos de células B usados na construção da quimera foram sintetizados e também testados em ELISA frente às mesmas amostras, assim como um extrato antigênico solúvel de Leishmania braziliensis (SLA). Os resultados mostraram que a proteína quimera apresentou sensibilidade e especificidade de 100% para diagnosticar a LV, LT e LV/HIV, enquanto os peptídeos sintéticos apresentaram sensibilidade variando entre eles de 9,1% a 90,9% para amostras de LT e 76,8% a 99,2% para amostras de LV e LV/HIV, já os valores de especificidade atingiram 98,3% a 99,1% para LT e 67,1% a 95,7% para LV e LV/HIV. O SLA apresentou sensibilidade e especificidade de 18,2% e 98,3% para LT, e 56,8% a 69,5% para amostras de LV e LV/HIV, respectivamente. Uma avaliação prognóstica preliminar mostrou ainda que os anticorpos anti-quimera diminuíram em níveis significativos, quando comparada a reatividade sorológica antes e seis meses após o tratamento, sugerindo um possível papel prognóstico da quimera para as leishmanioses. O presente estudo, mostrou-se eficaz na construção e avaliação de novos candidatos, que demonstram ter um bom desempenho na detecção diagnóstica e prognóstica para as leishmanioses e dos casos de coinfecção LV/HIV.


Leishmaniasis are neglected tropical diseases with high endemicity that affect thousands of people in the world. Infection is caused by protozoan parasites of the genus Leishmania. The biological diversity between species is what allows determining the clinical manifestations, either in the form of visceral leishmaniasis (VL) or tegumentary leishmaniasis (TL). Among these clinical manifestations, VL is considered the most serious, due to its high lethality and great emergence in individuals with infection caused by the human immunodeficiency virus (HIV). Currently, the control and prevention measures adopted by the World Health Organiza-tion (WHO) are based on a combination of intervention strategies against the infection, since an effective and early diagnosis is essential to intervene with the appropriate treatment, decrea-sing mortality rates and evolution of clinical complications. However, the serological tests used show impaired sensitivity and specificity in patients with leishmaniasis and/or coinfected with VL/HIV, due to low levels of anti-leishmanial antibodies or the presence of diseases that cause cross-reaction, leading to false-positive results. The sensitivity also becomes variable in treated patients, since the serology can remain positive for months or years after the end of the trea-tment and cure of the disease. Seeking to solve this problem, the identification of new antigens, through bioinformatic analysis associated with immunoproteomic, has allowed the detection of new proteins with potential diagnostic application. In previous studies, the hypothetical proteins LiHyT, LiHyD, LiHyV and LiHyP were found in species of Leishmania spp, and evaluated in their recombinant versions through ELISA assays, and satisfactory results were obtained for the detection of human and canine VL. Based on this information, the present work aimed to develop a recombinant chimera protein through on the prediction of specific linear epitopes of B cells derived from these four antigenic proteins of L. infantum and to evaluate its diagnostic potential, as well as the individual peptides that constitute it, against human leishmaniasis, as well as co-infection with HIV, in addition to testing them as possible prognostic markers of patients after VL and TL treatment. The amino acid sequences of the proteins were evaluated and eight B cell epitopes were predicted and used in the construction of a new chimeric protein. The protein was expressed, purified and evaluated as a recombinant antigen in ELISA for the diagnosis of VL, TL, VL/HIV co-infection and prognosis in samples from patients treated for VL and TL. The B cell epitopes used in the construction of the chimera were synthesized and also tested in ELISA against the same samples, as well as a soluble Leishmania braziliensis antigenic extract (SLA). The results showed that the chimera protein apresented sensitivity and specificity of 100% for diagnosing VL, TL and VL/HIV, while the synthetic peptides showed sensitivity ranging from 9.1% to 90.9% for TL samples and 76.8 % to 99.2% for VL and VL/HIV samples, while the specificity values reached from 98.3% to 99.1% for TL and 67.1% to 95.7% for VL and VL/HIV. The SLA showed sensitivity and specificity of 18.2% and 98.3% for TL, and 56.8% to 69.5% for VL and VL/HIV samples, respectively. A preliminary prog-nostic evaluation also showed that anti-chimera antibodies significantly decreased when com-pared to serological reactivity before and six months after treatment, suggesting a possible prognostic role of the antigen for leishmaniasis. The present study proved to be effective in the construction and evaluation of new candidates, who demonstrate good performance in diagnos-tic and prognostic detection for leishmaniasis and VL/HIV co-infection.


Subject(s)
Leishmania braziliensis , Leishmania infantum , Neglected Diseases , Epitopes, B-Lymphocyte , Computational Biology , Academic Dissertation
6.
Rev. bras. cir. cardiovasc ; 37(6): 801-806, Nov.-Dec. 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1407328

ABSTRACT

ABSTRACT Introduction: In this study, we aimed to present three different methods for symptomatic aberrant right subclavian artery (ARSA) surgery. Methods: We identified 11 consecutive adult patients undergoing symptomatic and/or aneurysmal ARSA repair between January 2016 and December 2020. Symptoms were dysphagia (n=8) and dyspnea + dysphagia (n=3). Six patients had aneurysm formation of the ARSA (mean diameter of 4.2 cm [range 2.8 - 6.3]). All data were analyzed retrospectively. Results: Median age of the patients (7 females/4 males) was 55 years (range 49 - 62). The first four patients (36.4%) underwent hybrid repair using thoracic endovascular aortic repair (TEVAR) and bilateral carotid-subclavian artery bypass (CScBp). Three patients (27.2%) were treated by open ARSA resection/ligation with left mini posterolateral thoracotomy (LMPLT) and right CScBp. And the last four patients (36.4%) underwent ARSA resection/ligation with LMPLT and ascending aorta-right subclavian artery bypass with upper mini sternotomy (UMS). Two of the four patients who underwent TEVAR + bilateral CScBp had continuing dysphagia cause of persistent esophageal compression. Brachial plexus injury developed in one of three patients who underwent LMPLT + right CScBp. Pleural effusion treated with thoracentesis alone was observed in one of four patients who underwent UMS + LMPLT. Conclusion: Among the symptomatic and/or aneurysmal ARSA treatment approaches, surgical and hybrid methods are used. There is still no consensus on how to manage these patients. In our study, we recommend the UMS + LMPLT method, since the risk of complications with anatomical bypass is less, and we have more successful surgical results.

7.
Chinese Journal of Perinatal Medicine ; (12): 545-549, 2022.
Article in Chinese | WPRIM | ID: wpr-958108

ABSTRACT

Objective:To analyze fetal sex chromosome abnormalities in prenatal diagnosis based on amniotic fluid cell culture.Methods:Clinical data of 12 164 pregnant women who underwent amniocentesis in Maternal and Child Health Hospital of Hunan Province from January 2017 to December 2020 were retrospectively analyzed. For those diagnosed with fetal sex chromosome abnormalities, the results of karyotyping and chromosome microarray analysis (CMA) were analyzed and described.Results:(1) Among the 12 164 cases, fetal sex chromosome abnormalities were detected in 387 cases (3.2%), including 351 cases with abnormal sex chromosome karyotype and 36 with sex chromosome microdeletion/microduplication. (2) High-risk patients indicated by non-invasive prenatal test (NIPT) had the highest proportion of sex chromosomes abnormalities (74.2%, 287/387), followed by those with other ultrasound abnormalities (8.5%, 33/387), high risk of Down syndrome screening (7.0%, 27/387), advanced maternal age (4.7%, 18/387), history of adverse pregnant or delivery (3.3%, 13/387), and nuchal translucency thickening or cervical lymphatic hygroma (2.3%, 9/387). (3) Detected chromosome karyotype abnormalities included numerical abnormalities [73.2%(257/351)], mosaicism [18.8(66/351)], and structural abnormalities [8.0%(28/351)], among which, 47,XXY [46.7%(120/257)], 45,X/46,XX[48.5%(32/66)], and X chromosome deletion [39.3%(11/28)] were the most common, respectively. Among 36 sex chromosome microdeletions/microduplications cases, 15(41.7%) were with pathogenic copy number variation (CNV), including 14 cases of X chromosome microdeletion/microduplication; 7(19.4%) with benign CNV, and 14(38.9%) with CNV of unknown clinical significance. The fragment size [ M (min-max)] of the 15 pathogenic CNV was 1.68 Mb(0.37-9.20 Mb). Of the nine cases with microdeletions, seven were found with deletion in the Xp22.31 region. Conclusions:Numerical abnormalities are the most common fetal sex chromosome abnormalities detected from amniotic fluid samples. Others included mosaicism and chromosome structure abnormalities.

8.
Acta Pharmaceutica Sinica ; (12): 2696-2708, 2022.
Article in Chinese | WPRIM | ID: wpr-941512

ABSTRACT

CDKs proteins are a kind of cell cycle protein-dependent kinases, which serve as important roles in controlling cell division and transcriptional stages. Among them, CDK9, as a key regulator responsible for the transcriptional elongation of cells, drives the development of various malignant cells and is considered as an important target in the field of anti-tumor drug development. However, the CDK family proteins feature high conservativeness and similarity in structure, leading to the poor selectivity and severe side effects for traditional small-molecular CDK9 inhibitors, which has limited their clinical applications. In view of this, there is an urgent need to investigate CDK9 targets through a novel strategy. The PROTAC is an emerging drug discovery strategy that the degrader could specifically recognize the target protein through indirect linkage with ubiquitin ligases and ultimately eliminate the target protein through the ubiquitination degradation system. This paper provides a brief overview of the structure and function of CDK9 protein, its relationship with the poor prognosis of clinical diseases, as well as the currently reported small molecular inhibitors. The latest research progress on the targeted degradation of CDK9 protein based on PROTAC technology is highlighted. Finally, the development prospects of this target protein in this novel technology field are summarized and prospected, aiming to provide a reference for the development of antitumor drugs in this direction.

9.
Acta Pharmaceutica Sinica ; (12): 313-320, 2022.
Article in Chinese | WPRIM | ID: wpr-922930

ABSTRACT

In recent years, the targeted protein degradation technology has developed quickly, with proteolysis-targeting chimera (PROTAC) as the best-known strategy through exploring the ubiquitin-proteasome system. A number of new targeted protein degradation strategies have been emerging to expand the scope of protein degradation technology, including lysosome-targeting chimeras (LYTACs), autophagy-targeting chimeras (AUTACs), autophagosome-tethering compounds (ATTECs) and chimeras based on chaperone-mediated autophagy (CMA). The emerging methodologies have explored another important protein degradation system in eukaryotes-lysosomal systems, such as the endosome-lysosome pathway and the autophagy-lysosome pathway. This review summaries the mechanisms and features of different strategies for targeted protein degradation, with a special emphasis on the new targeted protein degradation technologies, such as their current status, advantages and limitations.

10.
Acta Pharmaceutica Sinica ; (12): 1571-1579, 2021.
Article in Chinese | WPRIM | ID: wpr-881553

ABSTRACT

Local focal adhesion kinase (FAK) is a non-receptor intracellular tyrosine kinase that plays an important role in tumor initiation, development, metastasis and invasion, and is considered to be an important target for the development of antineoplastic drugs. It has both kinase-dependent and non-kinase-dependent scaffolding functions. However, traditional small molecular inhibitors can only inhibit its kinase-dependent activity, so it is difficult to target the kinase-independent scaffolding function. Therefore, there is an urgent need for novel strategies to enhance FAK targeting to lay the foundation for determining the druggability and discovery of FAK inhibitors. Proteolysis targeting chimera (PROTAC) is a new drug development strategy that can recruit E3 ligase to specifically ubiquitinylate target proteins for degradation through the proteasome system. The unique mechanism of action of the PROTAC system could be used to target and degrade the FAK protein, thus eliminating the scaffolding function of FAK. In this review, FAK protein, the signaling pathway, and small molecule inhibitors are briefly described, and the latest research progress in targeting the degradation of FAK using PROTAC technology is summarized.

11.
Chinese Pharmacological Bulletin ; (12): 749-755, 2021.
Article in Chinese | WPRIM | ID: wpr-1014430

ABSTRACT

The ubiquitin-proteasome pathway is one of the most important pathways of cell protein degradation in eukaryotes, and plays an important role in the regulation of cell proliferation, differentiation, apoptosis, DNA repair and other physiological activities. E3 ubiquitin ligase is the major component of ubiquitinproteasome system, which is responsible for substrate recognition. The abnormal regulation of E3 ubiquitin ligase may cause many diseases such as cancer, Alzheimer's disease and Parkinson's disease. Here, we summarizes the progress of drugs targeting E3 ubiquitin ligase in cancer, Alzheimer's disease, Parkinson's disease, diabetic complications, atherosclerosis, and inflammatory bowel diseases. At present, only a few of small molecule antagonists or agonists targeting E3 ubiquitin ligase are under development. The study of natural products in China is leading the way in the world, and numerous natural products have been identified for pharmacological effects on E3 ubiquitin ligase, which may open up a new avenue for multiple complex diseases.

12.
Journal of Zhejiang University. Science. B ; (12): 1-2, 2020.
Article in English | WPRIM | ID: wpr-1010511

ABSTRACT

This special feature contains three review articles that summarize recent advances pertaining to tumor immunobiology. Normalization of antitumor immunity through checkpoint inhibitors has achieved significant clinical success and benefited many cancer patients. However, not all cancer patients respond to these treatments, and among the responders, some may develop resistance and others may suffer autoimmunity that requires intervention. Tumor immunotherapy holds promise for further improving the survival of cancer patients, but deeper understanding of immunological networks that regulate anti- and pro-tumor immunity is needed. The review papers collected in this issue cover a few topics that may stimulate future interest in the relevant research field.


Subject(s)
Humans , Immunotherapy, Adoptive/methods , Lymphatic Vessels/physiology , MicroRNAs/physiology , Neoplasms/therapy , Receptors, Chimeric Antigen/immunology , T-Lymphocytes/immunology
13.
Journal of Shanghai Jiaotong University(Medical Science) ; (12): 729-735, 2020.
Article in Chinese | WPRIM | ID: wpr-843165

ABSTRACT

Objective • To establish a rapid method to evaluate the activity of agonistic antibody using OX40 (tumor necrosis factor receptor superfamily member 4)/FcγR (Fcγ receptor)-humanized mice. Methods • Bone marrow cells from OX40-humanized mice and FcγR-humanized mice were collected and mixed with equal ratio. Then the mixed bone marrow cells were administrated into irradiated wild-type mice through the tail veins. The reconstruction efficiency of the immune system was confirmed by detecting the expression of hOX40 and hFcγR in the immune cells of chimera mice. After the chimera mice were generated successfully, they were used to evaluate the immunostimulatory activity of anti-hOX40 antibodies to CD4+ or CD8+ T cells. The results of flow cytometry were statistically analyzed. The unpaired t-test was used to compare the means between the two groups, and oneway ANOVA was used to compare the means between multiple groups. Results • Flow cytometry analysis showed that wild-type recipient mice were efficiently reconstituted with hFcγR expressing cells and hOX40 expressing cells to generate OX40/FcγR-humanized bone marrow chimera mice. In these mice, B cells and myeloid cells expressed hFcγRs (P<0.05), and T cells expressed hOX40 upon in vitro stimulation (P<0.05). When these mice were used to evaluate the immunostimulatory activity of anti-hOX40 antibody, significant expressions of IFN-γ and hOX40 were observed (P<0.05). Conclusion • OX40/FcγR-humanized bone marrow chimera mice are generated based on hFcγR expressing cells and hOX40 expressing cells, suggesting a rapid method to build a mouse model with both hFcγR and hOX40 expression. These mice are suitable for evaluating the immunostimulatory activity of agonistic human anti-hOX40 antibodies.

14.
Acta Pharmaceutica Sinica ; (12): 1707-1725, 2020.
Article in Chinese | WPRIM | ID: wpr-825169

ABSTRACT

Pharmacological activity and drug likeness depend in principle upon the microscopic structure and macroscopic properties of drugs, which reside in their molecular structures. By means of medicinal chemistry the evolution of an active compound to a novel drug (NME) essentially makes the two pillars coexistence in one chemical structure, which either could merge as an intrinsic structure or connect from external fragments to each other with covalent bonds. Since the new millennium the advance in biology provides several knowledge and technologies, for example humanized monoclonal antibody, proteasome-ubiquitin system, allosteric modulation, natural macromolecules, structural biology, etc., for innovation of novel medicines. Taking several examples on marketed drugs or drug candidates in clinical trials, this article tries to concisely illustrate R & D conception of biology-driven drug design.

15.
Chinese Journal of Perinatal Medicine ; (12): 397-399, 2019.
Article in Chinese | WPRIM | ID: wpr-756126

ABSTRACT

We reported a case of mosaic trisomy 2.The patient was a 29-year-old gravida who underwent amniocentesis at 20 weeks of gestation because of high risk of trisomy-21 in the first trimester screening.The test result revealed a karyotype of 47,XN,+2[10]/46,XX[40].At 26 gestational weeks,the fetus was found severe fetal growth restriction and oligohydramnios which was considered to be at risk of mosaic trisomy 2.The pregnancy was terminated at 27+ gestational weeks.The fetus had obviously abnormal appearances,including dolichocephaly,low-set ears,and micromandible.Autopsy was not performed due to the parents' refusal.

16.
Journal of Shanghai Jiaotong University(Medical Science) ; (12): 1277-1282, 2018.
Article in Chinese | WPRIM | ID: wpr-843556

ABSTRACT

Objective • To establish a method for identifying the chimeric rates in Down syndrome chimeric mice, and study the chimeric rules in different organs. Methods • The proportion of trisomic cells (Tc1 cells) in different organs was calculated by detecting the relative quantity of human chromosome 21 (Hsa21) and mouse chromosome 15 (Mmu15) in samples. The relative quantity of Hsa21 and Mmu15 was evaluated with specific primers for genes SIM2 on Hsa21 and Derl1 on Mmu15, respectively, by quantitative real time PCR (qPCR) technology. Results • Three mice were chimeras and the chimeric levels of Tc1 cells were different in various tissues. The chimeric rates in hearts of these 3 mice were 8.98%, 21.71% and 57.70%; in cerebellums, the chimeric rates were 5.62%, 20.17% and 40.43%; in brains, the rates were 8.48%, 15.35% and 20.45%; in livers, the rates were 2.66%, 6.50% and 16.84%; and in spleens, the rates were 1.73%, 3.80% and 11.80%. Conclusion • The chimeric rate of trisomic cells in Down syndrome chimeric mice can be detected by qPCR technology by using primers for genes on specific chromosomes. The chimerism occurs in the hearts, cerebellums, brains, livers and spleens of the chimeric mice and the chimeric rate of Tc1 cells tends to be the highest in the hearts.

17.
Chinese Journal of Perinatal Medicine ; (12): 18-23, 2018.
Article in Chinese | WPRIM | ID: wpr-711173

ABSTRACT

Objective To assess the positive predictive value (PPV) of fetal sex chromosome aneuploidy (SCA) identified by non-invasive prenatal testing (NIPT) and investigate families' acceptance of SCA fetus. Methods All suspected SCA cases screened by NIPT from singletons were reviewed in Prenatal Diagnosis Center of Shanghai First Maternity and Infant Hospital from April 1, 2015 to October 31, 2017. Maternal age, NIPT indications, prenatal diagnosis protocols, testing results and their pregnancy determinations were analyzed. Results NIPT was provided to 35827 singletons and 86 suspected SCA cases were identified out of 35823 successful ones, giving a positive detection rate of 0.24%. The average maternal age was (31.5±5.0) years. After genetic counseling, 20 patients declined prenatal diagnosis,the rest 66 cases proceeded with aminiocentesis and fetal chromosomal testing, of which 32 were cytogenetically diagnosed as SCA with the PPV of 48.5% . The SCA fetus consisted of 25 sex chromosome trisomies (seven cases of 47,XXX, three cases of 47,XYY and 15 cases of 47,XXY), one monosomy X (45,X), three mosacisms (47,XXY/48,XXYY, 47,XXX/45,X, 45,X/46,XX, one for each) and three microdeletions/microduplications. Besides, two false positive NIPT cases were proved to be low level of maternal mosacism (45,X/46,XX, 5% and 10% for each). After genetic counseling, 17 out of 20 who declined prenatal diagnosis and 9 out of 32 who diagnosed fetal SCAs continued their pregnancies, with a combined proportion of continued pregnancy of 50%. Thirty-four pregnancies were also continued after exclusion of SCA. Interestingly, the proportion of continued pregnancy among those sex chromosomal trisomy fetuses was only 32%(8/25). Conclusions As a safe and rapid prenatal testing for common autosomal aneuploidies, NIPT could also identify some types of SCA, but with relatively low PPV. More long-term researches are required to determine its sensitivity and specificity. For some types of SCA with mild phenotypes, some family would continue the pregnancy. Therefore, limitations of NIPT should be appropriately explained during both pre- and post-testing counseling.

18.
Fudan University Journal of Medical Sciences ; (6): 33-36, 2017.
Article in Chinese | WPRIM | ID: wpr-695746

ABSTRACT

Chromosome abnormality is a serious congenital disease,which was usually researched in genetic diseases and prenatal diagnosis.In recent years,some special STR profile and pseudo-exclusion case caused by abnormal chromosome are found in forensic DNA test.We reviewed several common chromosome abnormality contained trisomy syndrome,uniparental disomy and Chimera were reported in forensic medicine to provide reference for forensic DNA workers.

19.
Chinese Journal of Biotechnology ; (12): 975-985, 2016.
Article in Chinese | WPRIM | ID: wpr-242282

ABSTRACT

With the advancements of stem cells and regenerative medicine, interspecies chimera has become a hot topic and will pave a new way of providing donor sources in organ transplantation. However, the interspecies chimera is confronted with a number of scientific questions and technical obstacles, including selections of appropriate embryonic stage and appropriate culture medium; those factors will deeply influence the developmental balance between donor cells and receptor embryos. Due to its relatively rapid reproductive cycle and similar organ size to human's, porcine is a very potential donor candidate to study these questions. To compare the development and chimeric efficiency of interspecies embryos, we tested and evaluated three different culture systems, PZM-3 (Porcine zygotic medium), culture medium for iPSCs (N2B27) and 3.5 h of N2B27 before PZM-3 (N2B27(3.5 h)), and two different embryonic stages, 8-cell and blastocyst in mouse-porcine chimeric embryos using parthenogenetically activated porcine embryos and mouse induced pluripotent stem cells (miPS). The results showed that, PZM-3 was beneficial for both development of chimeric embryos and miPSCs proliferation in porcine embryos in the 8-cell injection group. After early blastocyst injection, the chimeric efficiency did not appear significantly different among the three culture systems but was lower than 8-cell injection. In summary, the results suggest that 8-cell injection and PZM-3 culture medium are more beneficial to the in vitro development and chimeric efficiency of mouse-porcine chimeric embryos.


Subject(s)
Animals , Mice , Blastocyst , Chimera , Culture Media , Embryo Culture Techniques , Embryo, Mammalian , Embryonic Development , Induced Pluripotent Stem Cells , Cell Biology , Swine
20.
The Journal of Practical Medicine ; (24): 1916-1919, 2016.
Article in Chinese | WPRIM | ID: wpr-494502

ABSTRACT

Objective To examine an in vivo method for the differentiation of induced pluripotent stem cells (iPSCs) into thymic epithelial cells (TECs) in mice. Methods Green fluorescent protein-expressing iPS cells, derived from C57BL/6 mice, were injected into blastocysts from ICR mice. Chimeric blastocysts were then transferred into uteri of E2.5 pseudopregnant mice. Chimeric mouse could be identified by coat color 10 days after birth. The chimeric thymus was transplanted under the renal capsule of BALB/c nude mice. The spleen was cut out from the thymus-transplanted nude mice and the cells were dispersed and analyzed by a flow cytometer 4 weeks after transplantation. Results Chimeras were born 17 days after embryo transfer and 13 live-born chimeras were obtained. The contribution of iPSC-derived cells in the chimeras ranged from 5% to at most 90%. Typical thymic epithelium structure consisted of green fluorescent protein-expressing cells in chimera. The iPSCs-derived thymic epithelial cells could support the generation of new T cells. Conclusion The results indicate that mouse iPS cells can differentiate in vivo towards normally functioning TECs.

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