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1.
Insect Sci ; 2024 Mar 21.
Article in English | MEDLINE | ID: mdl-38511329

ABSTRACT

Mosquitoes (Anopheles sinensis), widely geographically distributed in Asia including China, are the primary vector of the malaria parasite Plasmodium vivax and other parasitic diseases such as Malayan filariasis. An. sinensis can survive through low winter temperatures. Aquaporin channels are found in all life forms, where they facilitate environmental adaptation by allowing rapid trans-cellular movement of water (classical aquaporins) or water and solutes such as glycerol (aquaglyceroporins). Here, we identified and characterized 2 aquaporin (AQP) homologs in An. sinensis: AsAQP2 (An. sinensis aquaglyceroporin) and AsAQP4 (An. sinensis aquaporin). When expressed in frog (Xenopus laevis) oocytes, AsAQP2 transported water, glycerol, and urea; AsAQP4 transported only water. Water permeation through AsAQP2 and AsAQP4 was inhibited by mercuric chloride. AsAQP2 expression was slightly higher in adult female mosquitoes than in males, and AsAQP4 expression was significantly higher in adult males. The 2 AsAQPs were highly expressed in Malpighian tubules and midgut. AsAQP2 and AsAQP4 expression was up-regulated by blood feeding compared with sugar feeding. At freezing point (0 °C), the AsAQP4 expression level increased and An. sinensis survival time reduced compared with those at normal temperature (26 °C). At low temperature (8 °C), the AsAQP2 and AsAQP4 expression levels decreased and survival time was significantly longer compared with those at 26 °C. These results suggest that AsAQP2 and AsAQP4 have roles in water homeostasis during blood digestion and in low temperature adaptation of A. sinensis. Together, our results show that the 2 AQPs are important for mosquito diuresis after blood feeding and when exposed to low temperatures.

2.
J Nanobiotechnology ; 21(1): 407, 2023 Nov 03.
Article in English | MEDLINE | ID: mdl-37924105

ABSTRACT

Rapid hemostasis of uncontrolled bleeding following traumatic injuries, especially accompanied by coagulopathies, remains a significant clinical challenge. Extracellular vesicles (EVs) show therapeutic effects for fast clotting. However, low yield, specific storage conditions, and lack of proper carriers have hindered EVs' clinical application. Herein, we establish an optimized procedure method to generate lyophilized mesenchymal stem cell-derived apoptotic vesicles (apoVs) with adhesive hydrogel sponge to show superior procoagulant activity for traumatic hemorrhage. Mechanistically, apoVs' procoagulant ability stems from their high tissue factor (TF) and phosphatidylserine (PS) expression independent of hemocytes and circulating procoagulant microparticles (cMPs). Their stable hemostatic capability was maintained after 2-month room temperature storage. Subsequently, we mixed apoVs with both phenylboronic acid grafted oxidized hyaluronic acid (PBA-HA) and poly(vinyl alcohol) (PVA) simultaneously, followed by lyophilization to construct a novel apoV-encapsulated hydrogel sponge (apoV-HS). Compared to commercial hemostats, apoV-HS exhibits rapid procoagulant ability in liver-laceration and femoral artery hemorrhage in rat and rabbit models of coagulopathies. The combination of high productivity, physiological stability, injectability, plasticity, excellent adhesivity, biocompatibility, and rapid coagulant property indicates that apoV-HS is a promising therapeutic approach for heavy hemorrhage in civilian and military populations.


Subject(s)
Extracellular Vesicles , Hemostatics , Rats , Animals , Rabbits , Adhesives , Hydrogels , Hemostatics/pharmacology , Hemorrhage/drug therapy
3.
Malar J ; 22(1): 163, 2023 May 24.
Article in English | MEDLINE | ID: mdl-37226272

ABSTRACT

BACKGROUND: Malaria is a worldwide infectious disease. For countries that have achieved malaria elimination, the prevention of re-establishment due to infections in returned travellers has become important. The accurate and timely diagnosis of malaria is the key in preventing re-establishment, and malaria rapid diagnostic tests (RDTs) are frequently used due to their convenience. However, the RDT performance in Plasmodium malariae (P. malariae) infection diagnosis remains unknown. METHODS: This study analysed epidemiological features and diagnosis patterns of imported P. malariae cases from 2013 to 2020 in Jiangsu Province and evaluated the sensitivity of four parasite enzyme lactate dehydrogenase (pLDH)-targeting RDTs (Wondfo, SD BIONLINE, CareStart and BioPerfectus) and one aldolase-targeting RDT(BinaxNOW) for P. malariae detection. Furthermore, influential factors were investigated, including parasitaemia load, pLDH concentration and target gene polymorphisms. RESULTS: The median duration from symptom onset to diagnosis among patients with P. malariae infection was 3 days, which was longer than that with Plasmodium falciparum (P. falciparum) infection. The RDTs had a low detection rate (39/69, 56.5%) among P. malariae cases. All tested RDT brands had poor performance in P. malariae detection. All the brands except the worst-performing SD BIOLINE, achieved 75% sensitivity only when the parasite density was higher than 5000 parasites/µL. Both pLDH and aldolase showed relatively conserved and low gene polymorphism rates. CONCLUSIONS: The diagnosis of imported P. malariae cases was delayed. The RDTs had poor performance in P. malariae diagnosis and may threaten the prevention of malaria re-establishment from returned travellers. The improved RDTs or nucleic acid tests for P. malariae cases are urgently needed for the detection of imported cases in the future.


Subject(s)
Malaria, Falciparum , Malaria , Humans , Plasmodium malariae , Rapid Diagnostic Tests , Malaria/diagnosis , China , Fructose-Bisphosphate Aldolase , Aldehyde-Lyases , L-Lactate Dehydrogenase
4.
Acta Trop ; 238: 106793, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36509131

ABSTRACT

PURPOSE: The fraction antigen of Schistosoma japonicum (107-121 kDa) eggs can be used for treatment efficacy monitoring, but the methods are laborious. This study analyzed the antigen and its feasibility for infection screening and treatment efficacy monitoring, which is the key to schistosomiasis control. METHODS: The fraction antigens have been analyzed by shotgun mass spectrometry. The recombinant proteins of candidates from the fraction antigens have been prokaryotic expression and purification in large amounts with high purity. The sera have been collected from rabbits and mice models of schistosomiasis infection and treatment. ELISA evaluated the diagnostic value of the candidate proteins. RESULTS: SJCHGC00820 and SJCHGC06900, with higher credibility, were identified through Shotgun mass spectrometry. ELISA results showed that rSj00820 has a diagnostic value for schistosomiasis (positive OD/negative OD P/N=3.6), while rSj06900 showed negative (P/N)<2. In rabbits, the specific serum antibodies for SjHSP90(rSj00820) in the infected animals peaked 6 weeks after infection and gradually decreased after treatment, reaching negative levels at 11 weeks. SjHSP90-ELISA was used to test serum samples from infected mice. The sensitivity and specificity reached >90%, similar to the diagnostic value obtained with soluble egg antigen (SEA) (SEA-ELISA). After treatment, the negative conversion rate reached >80%, significantly superior to SEA-ELISA. CONCLUSIONS: The SjHSP90-ELISA can be used for the immunological diagnosis and treatment efficacy monitoring of schistosomiasis. The study lays a foundation for further developing screening and diagnostic kits.


Subject(s)
Schistosoma japonicum , Schistosomiasis japonica , Schistosomiasis , Animals , Rabbits , Mice , Schistosomiasis japonica/diagnosis , Schistosomiasis japonica/drug therapy , Antigens, Helminth , Antibodies, Helminth , Schistosomiasis/diagnosis , Schistosomiasis/drug therapy , Schistosoma japonicum/genetics , Enzyme-Linked Immunosorbent Assay/methods , Recombinant Proteins , Sensitivity and Specificity , Treatment Outcome
5.
iScience ; 26(1): 105725, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36579133

ABSTRACT

The emergence and spread of artemisinin-tolerant malaria parasites threatens malaria control programmes worldwide. Mutations in the propeller domain of the Kelch13 protein confer Plasmodium falciparum artemisinin resistance (ART-R). ART-R is linked to the reduced susceptibility of temporary growth-arrested ring-stage parasites, but the metabolic mechanisms remain elusive. We generated two PfKelch13 mutant lines via CRISPR-Cas9 gene editing which displayed a reduced susceptibility accompanied by an extended ring stage. The metabolome of ART-induced ring-stage growth arrest parasites carrying PfKelch13 mutations showed significant alterations in the tricarboxylic acid (TCA) cycle, glycolysis, and amino acids metabolism, pointing to altered energy and porphyrin metabolism with metabolic plasticity. The critical role of these pathways was further confirmed by altering metabolic flow or through chemical inhibition. Our findings uncover that the growth arrestment associated with ART-R is potentially attributed to the adaptative metabolic plasticity, indicating that the defined metabolic remodeling turns out to be the trigger for ART-R.

6.
Bioact Mater ; 19: 626-641, 2023 Jan.
Article in English | MEDLINE | ID: mdl-35600968

ABSTRACT

Over 300 billion of cells die every day in the human body, producing a large number of endogenous apoptotic extracellular vesicles (apoEVs). Also, allogenic stem cell transplantation, a commonly used therapeutic approach in current clinical practice, generates exogenous apoEVs. It is well known that phagocytic cells engulf and digest apoEVs to maintain the body's homeostasis. In this study, we show that a fraction of exogenous apoEVs is metabolized in the integumentary skin and hair follicles. Mechanistically, apoEVs activate the Wnt/ß-catenin pathway to facilitate their metabolism in a wave-like pattern. The migration of apoEVs is enhanced by treadmill exercise and inhibited by tail suspension, which is associated with the mechanical force-regulated expression of DKK1 in circulation. Furthermore, we show that exogenous apoEVs promote wound healing and hair growth via activation of Wnt/ß-catenin pathway in skin and hair follicle mesenchymal stem cells. This study reveals a previously unrecognized metabolic pathway of apoEVs and opens a new avenue for exploring apoEV-based therapy for skin and hair disorders.

7.
PLoS Negl Trop Dis ; 16(12): e0010977, 2022 12.
Article in English | MEDLINE | ID: mdl-36469541

ABSTRACT

Plasmodium ovale curtisi and P. ovale wallikeri are both endemic in sub-Saharan Africa, the Middle East and Southeast Asia. Molecular surveillance data for drug resistance in P. ovale spp. is limited at present. We analysed polymorphisms in the podhfr, pocrt and pocytb genes of P. ovale spp. in 147 samples collected from travelers returning to China from Africa. Two podhfr mutations, S58R and S113N/T were detected in P. ovale curtisi with high/moderate frequencies of 52.17% and 17.39%, respectively. Evidence of positive selection (dN/dS = 2.41) was found for podhfr in P. ovale curtisi and decreased diversity (He) of microsatellite markers flanking the mutant alleles suggests that selective sweeps have occurred for both. Mutations E34G (1.50%) and L43V (1.50%) in pocrt of P. ovale curtisi, and E34G (3.70%), I102M (1.80%) and V111F (1.80%) of P. ovale wallikeri were found at low frequencies. Mutations R66K (6.20%), R75K (11.63%) and R95K (3.88%) of pocytb were found in both P. ovale curtisi and P. ovale wallikeri. These results suggest that the podhfr gene of P. ovale curtisi may be subject to drug selection in Africa, warranting further attention. We observed significant differences in the prevalence and distribution of podhfr mutations between the two P. ovale species, suggestive of fundamental biological differences between them.


Subject(s)
Malaria , Plasmodium ovale , Humans , Plasmodium ovale/genetics , Tetrahydrofolate Dehydrogenase/genetics , Malaria/epidemiology , Africa/epidemiology , Mutation
8.
Parasit Vectors ; 15(1): 428, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-36380374

ABSTRACT

BACKGROUND: Plasmodium vivax rhoptry-associated membrane antigen (RAMA) is a glycophosphatidylinositol-anchored membrane protein currently under consideration as a malaria vaccine candidate. Immunoglobulin G (IgG) antibodies induced by P. vivax RAMA (PvRAMA) have been proved to persist over 12 months in the sera of people infected with P. vivax. It has also been shown that through stimulation of peripheral blood mononuclear cells with PvRAMA in vitro, the antigen can induce CD4+ T cells to produce interleukin-10. However, the genetic diversity of the RAMA gene in isolates of P. vivax (pvrama) and the immunogenicity of PvRAMA in animals remain unclear. METHODS: Genomic DNA was extracted from blood samples (n = 25) of patients in Jiangsu Province, China with imported infections of P. vivax from endemic countries in South and Southeast Asia. The extract genomic DNA was used as templates to amplify the P. vivax rama gene (pvrama) by PCR, and the PCR products were then sequenced and analyzed by the DnaSP, MEGA, and GeneDoc software packages. Recombinant PvRAMA (rPvRAMA) protein was expressed and purified, and then used to immunize mice. Levels of total IgG and different IgG subclasses of rPvRAMA-immunized mice were evaluated by enzyme-linked immunosorbent assay. Also, spleen cells of rPvRAMA-immunized mice were stimulated with rPvRAMA in vitro and levels of T cells were measured by flow cytometry. RESULTS: The average pairwise nucleotide diversity (π) of the pvrama gene was 0.00190, and the haplotype diversity (Hd) was 0.982. The C-terminal of PvRAMA showed lower haplotype diversity compared to the N-terminal and was completely conserved at amino acid sites related to erythrocyte binding. To further characterize immunogenicity of the C-terminal of PvRAMA, mice were immunized with rPvRAMA antigen. The rPvRAMA protein induced antibody responses, with the end-point titer ranging from 1:10,000 to 1:5,120,000. IgG1 was the predominant IgG subclass in rPvRAMA-immunized mice, followed by IgG2b. In addition, levels of CD4+ and CD8+ T cells in the rPvRAMA-stimulated group were significantly higher than those in the phosphate-buffered saline-stimulated group (normal control group). CONCLUSIONS: The high conservation at specific amino acid sites and the high immunogenicity of the C-terminal of PvRAMA indicate the presence of conserved epitopes able to generate broadly reactive humoral and cellular immune responses. These findings support the potential of PvRAMA to serve as a vaccine candidate against P. vivax infection.


Subject(s)
Malaria Vaccines , Malaria, Vivax , Mice , Animals , Plasmodium vivax/genetics , CD8-Positive T-Lymphocytes , Leukocytes, Mononuclear , Antibodies, Protozoan , Protozoan Proteins/genetics , Malaria, Vivax/prevention & control , Antigens, Protozoan/genetics , Immunoglobulin G , Amino Acids
9.
Cell Death Dis ; 13(4): 365, 2022 04 18.
Article in English | MEDLINE | ID: mdl-35436982

ABSTRACT

Mesenchymal stem cells (MSCs) are a type of immunosuppressive stromal cell found in multiple tissues and organs. However, whether MSCs possess immunosupportive characteristics remains unclear. In this study, we showed that the lymph nodes contain immunosupportive MSCs. They produce and secrete a high level of MCP-1 to promote T-cell proliferation and differentiation, in contrast to bone marrow MSCs (BMMSCs), which repress T-cell activation. Unlike BMMSCs, lymph node MSCs (LNMSCs) fail to respond to activated T-cell-induced production of PD-L1 to induce T-cell apoptosis. Mechanistically, MCP-1 activates phospho-Erk to sustain T-cell proliferation and activation while it represses NF-κB/PD-L1 pathway to avoid induction of T-cell apoptosis. Interestingly, inflammatory lymph node-derived LNMSCs abolish their immunosupportive function due to reduction of MCP-1 expression. Finally, we show that systemic infusion of LNMSCs rescues immunosuppression in cytoxan (CTX)-treated mice. This study reveals a previously unrecognized mechanism underlying MSC-based immunoregulation using the MCP-1/PD-L1 axis to energize T cells and suggests a potential to use MSCs to treat immunosuppressive disorders.


Subject(s)
B7-H1 Antigen , Mesenchymal Stem Cells , Animals , B7-H1 Antigen/genetics , B7-H1 Antigen/metabolism , Cell Proliferation , Lymph Nodes/metabolism , Lymphocyte Activation , Mesenchymal Stem Cells/metabolism , Mice , T-Lymphocytes
10.
Ecotoxicol Environ Saf ; 237: 113553, 2022 Jun 01.
Article in English | MEDLINE | ID: mdl-35483147

ABSTRACT

Insecticide-based vector control measures play an important role in the prevention and control of insect-borne infectious diseases such as malaria; however, insecticide resistance has become a severe global problem for vector control. To date, the metabolic mechanism by which Anopheles sinensis, the most widely distributed malaria vector in China and Asia, detoxifies insecticides is not clear. In this study, the molecular metabolite changes in both the larval and adult stages of deltamethrin susceptible (DS) and deltamethrin-resistant (DR) An. sinensis mosquitoes were analysed by using liquid chromatography tandem mass spectrometry (LC-MS/MS) after exposure to deltamethrin. There were 127 differential metabolites in larval DR An. sinensis and 168 in adults. Five metabolites (glycerophosphocholine, deoxyguanosine, DL-methionine sulfoxide, D-myo-inositol-3-phosphate and N-acetyl-alpha-D-glucosamine1-phosphate) were downregulated in both DR larvae and adults, and one metabolite (aspartyl-glutamine) was upregulated, and the ratio of down- and up-regulation of these metabolites was 5:1. The differential metabolites between the DS and DR mosquitos were mainly classified into organic oxygen compounds, carboxylic acids and their derivatives, glycerophospholipids and purine nucleotides, and the common pathway enriched in both the larval and adult DR An. sinensis was glycerophospholipid metabolism. The findings of this study provide further mechanistic understanding of insecticide resistance in An. sinensis.


Subject(s)
Anopheles , Insecticides , Malaria , Pyrethrins , Animals , Chromatography, Liquid , Insecticide Resistance , Insecticides/toxicity , Larva , Malaria/prevention & control , Metabolome , Mosquito Vectors , Nitriles/toxicity , Pyrethrins/toxicity , Tandem Mass Spectrometry
11.
Mitochondrial DNA B Resour ; 7(3): 482-484, 2022.
Article in English | MEDLINE | ID: mdl-35311202

ABSTRACT

Anopheles anthropophagus (Xu and Feng 1975) is the major vector of malaria in Eastern and Southern China. The species An. anthropophagus is considered a synonym of An. lesteri (Baisas & Hu, 1936), although they differ in several key biological characteristics. Here, we report the complete mitochondrial genome of An. anthropophagus for the first time. The mitogenome of An. anthropophagus is a typical circular, double-stranded molecule with a total length of 15,413 base pairs, and contains 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and an AT-rich control region. A phylogenetic analysis of the complete mitogenomes of 16 species of Anopheles (Culicidae) revealed that An. anthropophagus is closely related to An. sinensis (Wiedemann 1828), in the family Culicidae. The An. anthropophagus mitogenome provides new data for further taxonomic and phylogenetic studies of the genus Anopheles.

12.
Nucleic Acids Res ; 50(6): 3413-3431, 2022 04 08.
Article in English | MEDLINE | ID: mdl-35288749

ABSTRACT

Heterochromatin-associated gene silencing controls multiple physiological processes in malaria parasites, however, little is known concerning the regulatory network and cis-acting sequences involved in the organization of heterochromatin and how they modulate heterochromatic gene expression. Based on systematic profiling of genome-wide occupancy of eighteen Apicomplexan AP2 transcription factors by ChIP-seq analysis, we identify and characterize eight heterochromatin-associated factors (PfAP2-HFs), which exhibit preferential enrichment within heterochromatic regions but with differential coverage profiles. Although these ApiAP2s target euchromatic gene loci via specific DNA motifs, they are likely integral components of heterochromatin independent of DNA motif recognition. Systematic knockout screenings of ApiAP2 factors coupled with RNA-seq transcriptomic profiling revealed three activators and three repressors of heterochromatic gene expression including four PfAP2-HFs. Notably, expression of virulence genes is either completely silenced or significantly reduced upon the depletion of PfAP2-HC. Integrated multi-omics analyses reveal autoregulation and feed-forward loops to be common features of the ApiAP2 regulatory network, in addition to the occurrence of dynamic interplay between local chromatin structure and ApiAP2s in transcriptional control. Collectively, this study provides a valuable resource describing the genome-wide landscape of the ApiAP2 family and insights into functional divergence and cooperation within this family during the blood-stage development of malaria parasites.


Subject(s)
Malaria , Plasmodium falciparum , Heterochromatin/genetics , Heterochromatin/metabolism , Humans , Malaria/parasitology , Protozoan Proteins/genetics , Protozoan Proteins/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism
13.
J Extracell Vesicles ; 11(7): e12240, 2022 06.
Article in English | MEDLINE | ID: mdl-36856683

ABSTRACT

Apoptotic vesicles (apoVs) are apoptotic cell-derived nanosized vesicles that play a crucial role in multiple pathophysiological settings. However, their detailed characteristics, specific surface markers, and biological properties are not fully elucidated. In this study, we compared mesenchymal stem cell (MSC)-derived apoVs and exosomes from three different types of MSCs including human bone marrow MSCs (hBMSCs), human adipose MSCs (hASCs), and mouse bone marrow MSCs (mBMSCs). We established a unique protein map of MSC-derived apoVs and identified the differences between apoVs and exosomes in terms of functional protein cargo and surface markers. Furthermore, we identified 13 proteins specifically enriched in apoVs compared to exosomes, which can be used as apoV-specific biomarkers. In addition, we showed that apoVs inherited apoptotic imprints such as Fas to ameliorate haemophilia A in factor VIII knockout mice via binding to the platelets' FasL to activate platelet functions, and therefore rescuing the blood clotting disorder. In summary, we systemically characterized MSC-derived apoVs and identified their therapeutic role in haemophilia A treatment through a previously unknown Fas/FasL linkage mechanism.


Subject(s)
Exosomes , Extracellular Vesicles , Hemophilia A , Humans , Animals , Mice , Proteomics , Apoptosis , Mice, Knockout
14.
ACS Nano ; 15(9): 14360-14372, 2021 09 28.
Article in English | MEDLINE | ID: mdl-34506129

ABSTRACT

Apoptosis is critical for maintaining bodily homeostasis and produces a large number of apoptotic extracellular vesicles (apoEVs). Several types of cancer cells display reduced expression of Fas on the cell surface and are thus capable of escaping Fas ligand-induced apoptosis. However, it is unknown whether normal cell-derived apoEVs can regulate tumor growth. In this study, we show that apoEVs can induce multiple myeloma (MM) cell apoptosis and inhibit MM cell growth. Systemic infusion of mesenchymal stem cell (MSC)-derived apoEVs significantly prolongs the lifespan of MM mice. Mechanistically, apoEVs directly contact MM cells to facilitate Fas trafficking from the cytoplasm to the cell membrane by evoking Ca2+ influx and elevation of cytosolic Ca2+. Subsequently, apoEVs use their Fas ligand to activate the Fas pathway in MM cells, leading to the initiation of apoptosis. This study identifies the role of apoEVs in inducing MM apoptosis and suggests a potential for apoEVs to treat MM.


Subject(s)
Extracellular Vesicles , Multiple Myeloma , Animals , Apoptosis , Mice , Multiple Myeloma/drug therapy
15.
Front Genet ; 12: 688606, 2021.
Article in English | MEDLINE | ID: mdl-34421996

ABSTRACT

Plasmodium falciparum surface-related antigen (SRA) is located on the surfaces of gametocyte and merozoite and has the structural and functional characteristics of potential targets for multistage vaccine development. However, little information is available regarding the genetic polymorphism of pfsra. To determine the extent of genetic variation about P. falciparum by characterizing the sra sequence, 74 P. falciparum samples were collected from migrant workers who returned to China from 12 countries of Africa between 2015 and 2019. The full length of the sra gene was amplified and sequenced. The average pairwise nucleotide diversities (π) of P. falciparum sra gene was 0.00132, and the haplotype diversity (Hd) was 0.770. The average number of nucleotide differences (k) for pfsra was 3.049. The ratio of non-synonymous (dN) to synonymous (dS) substitutions across sites (dN/dS) was 1.365. Amino acid substitutions of P. falciparum SRA could be categorized into 35 unique amino acid variants. Neutrality tests showed that the polymorphism of PfSRA was maintained by positive diversifying selection, which indicated its role as a potential target of protective immune responses and a vaccine candidate. Overall, the ability of the N-terminal of PfSRA antibodies to evoke inhibition of merozoite invasion of erythrocytes and conserved amino acid at low genetic diversity suggest that the N-terminal of PfSRA could be evaluated as a vaccine candidate against P. falciparum infection.

16.
Nucleic Acids Res ; 49(16): 9264-9279, 2021 09 20.
Article in English | MEDLINE | ID: mdl-34365503

ABSTRACT

Gametocytogenesis, the process by which malaria parasites produce sexual forms that can infect mosquitoes, is essential for the transmission of malaria. A transcriptional switch of the pfap2-g gene triggers sexual commitment, but how the complex multi-step process is precisely programed remains largely unknown. Here, by systematic functional screening of a panel of ApiAP2 transcription factors, we identify six new ApiAP2 members associated with gametocytogenesis in Plasmodium falciparum. Among these, PfAP2-G5 (PF3D7_1139300) was found to be indispensable for gametocytogenesis. This factor suppresses the transcriptional activity of the pfap2-g gene via binding to both the upstream region and exonic gene body, the latter is linked to the maintenance of local heterochromatin structure, thereby preventing initiation of sexual commitment. Removal of this repressive effect through pfap2-g5 knockout disrupts the asexual replication cycle and promotes sexual commitment accompanied by upregulation of pfap2-g expression. However, the gametocytes produced fail to mature fully. Further analyses show that PfAP2-G5 is essential for gametocyte maturation, and causes the down-regulation of pfap2-g and a set of early gametocyte genes activated by PfAP2-G prior to gametocyte development. Collectively, our findings reveal a regulation cascade of gametocyte production in malaria parasites, and provide a new target for transmission blocking interventions.


Subject(s)
Gametogenesis/genetics , Malaria, Falciparum/genetics , Plasmodium falciparum/genetics , Transcription, Genetic , Animals , Culicidae/parasitology , Gene Expression Regulation/genetics , Humans , Malaria, Falciparum/parasitology , Plasmodium falciparum/growth & development , Protozoan Proteins/genetics , Transcription Factors/genetics
17.
J Leukoc Biol ; 110(3): 565-576, 2021 09.
Article in English | MEDLINE | ID: mdl-34043832

ABSTRACT

Periodontitis is characterized by the periodontium's pathologic destruction due to the host's overwhelmed inflammation to the dental plaque. The bacterial infections and subsequent host immune responses have shaped a distinct microenvironment, which generally affects resident periodontal ligament stem cells (PDLSCs). Interestingly, recent studies have revealed that impaired PDLSCs may also contribute to the disturbance of periodontal homeostasis. The putative vicious circle underlying the interesting "positive feedback" of PDLSCs in the periodontitis niche remains a hot research topic, whereas the inseparable interactions between resident PDLSCs and the periodontitis niche are still not fully understood. This review provides a microscopic view on the periodontitis progression, especially the quick but delicate immune responses to oral dysbacterial infections. We also summarize the interesting crosstalk of the resident PDLSCs with their surrounding periodontitis niche and potential mechanisms. Particularly, the microenvironment reduces the osteogenic properties of resident PDLSCs, which are closely related to their reparative activity. Reciprocally, these impaired PDLSCs may disrupt the microenvironment by aggravating the host immune responses, promoting aberrant angiogenesis, and facilitating the osteoclastic activity. We further recommend that more in-depth studies are required to elucidate the interactions of PDLSCs with the periodontal microenvironment and provide novel interventions for periodontitis.


Subject(s)
Cell Communication , Periodontal Ligament/pathology , Periodontitis/pathology , Stem Cells/pathology , Humans , Immunity , Models, Biological , Periodontitis/immunology
18.
J Am Mosq Control Assoc ; 37(1): 38-40, 2021 03 01.
Article in English | MEDLINE | ID: mdl-33857314

ABSTRACT

Microbiota are vital for the development, physiology, and vectorial capacity of mosquitoes. The composition and role of microbiota in Anopheles species, especially Anopheles gambiae and Anopheles stephensi, have been extensively studied, but little is known about the microbiota of Anopheles species in China. We characterized the microbial communities of Anopheles dirus, Anopheles sinensis, and Anopheles lesteri by 16S rRNA sequencing. There were distinct differences in the composition of microbiota in An. lesteri and the other 2 species. The discriminatory genera in the 3 species were analyzed by the linear discriminant analysis effect size method. Our results provide an overview of the population structure of microbiota in 3 native Anopheles species and will pave the way for further understanding of their role in mosquito physiology and vector competence.


Subject(s)
Anopheles/microbiology , Bacteria/isolation & purification , Microbiota , Mosquito Vectors/microbiology , Animals , China , RNA, Bacterial/analysis , RNA, Ribosomal, 16S/analysis , Species Specificity
19.
Front Cell Infect Microbiol ; 11: 631545, 2021.
Article in English | MEDLINE | ID: mdl-33708645

ABSTRACT

Malaria, an infectious disease caused by Plasmodium parasites, still accounts for amounts of deaths annually in last decades. Despite the significance of Plasmodium falciparum as a model organism of malaria parasites, our understanding of gene expression of this parasite remains largely elusive since lots of progress on its genome and transcriptome are based on assembly with short sequencing reads. Herein, we report the new version of transcriptome dataset containing all full-length transcripts over the whole asexual blood stages by adopting a full-length sequencing approach with optimized experimental conditions of cDNA library preparation. We have identified a total of 393 alternative splicing (AS) events, 3,623 long non-coding RNAs (lncRNAs), 1,555 alternative polyadenylation (APA) events, 57 transcription factors (TF), 1,721 fusion transcripts in P. falciparum. Furthermore, the shotgun proteome was performed to validate the full-length transcriptome of P. falciparum. More importantly, integration of full-length transcriptomic and proteomic data identified 160 novel small proteins in lncRNA regions. Collectively, this full-length transcriptome dataset with high quality and accuracy and the shotgun proteome analyses shed light on the complex gene expression in malaria parasites and provide a valuable resource for related functional and mechanistic researches on P. falciparum genes.


Subject(s)
High-Throughput Nucleotide Sequencing , Plasmodium falciparum , Alternative Splicing , Gene Expression Profiling , Plasmodium falciparum/genetics , Proteomics , Transcriptome
20.
Autophagy ; 17(9): 2586-2603, 2021 09.
Article in English | MEDLINE | ID: mdl-32910719

ABSTRACT

Mesenchymal stem cell transplantation (MSCT) has been applied to treat a variety of autoimmune and inflammatory diseases. Psychosocial stress can aggravate disease progression in chronic inflammatory patients. Whether psychological stress affects MSCT is largely unknown. In this study we show that psychological stress attenuates therapeutic effects of MSCT in a DSS-induced colitis mouse model by elevating the levels of exosomal Mir7k/mmu-let-7 k (microRNA 7 k) in circulation. Mechanistically, Mir7k inhibits STAT3 pathway in donor MSCs, leading to upregulated expression of BECN1 (beclin 1, autophagy related) and, thus, activation of macroautophagy/autophagy. Inhibition of autophagy by blocking Mir7k or activating STAT3 signaling can restore MSCT-mediated therapy in psychologically stressed colitis mice. Our study identifies a previously unknown role of autophagy in regulating MSCT therapy via exosomal miRNA Mir7k.Abbreviations: BafA1: bafilomycin A1; BECN1: beclin 1, autophagy related; DAI: disease activity index; DAPI: 4',6-diamidino-2-phenylindole; DSS: dextran sulfate sodium; GFP: green fluorescent protein; HAI: histological activity index; IFNG/IFN-γ: interferon gamma; IL10: interleukin 10; IL1RN/IL-1Rra: interleukin 1 receptor antagonist; KD: knockdown; miRNA: microRNA; MSCs: mesenchymal stem cells; MSCT: mesenchymal stem cell transplantation; NTA: nanoparticle tracking analysis; PGE2: prostaglandin E2; SD: standard deviation; siRNA: small-interfering RNA; STAT3: signal transducer and activator of transcription 3; TEM: transmission electron microscopy; TGFB1/TGF-ß1: transforming growth factor, beta 1; Th17 cell: T helper cell 17; TNF/TNF-α: tumor necrosis factor; TNFAIP6/TSG6: tumor necrosis factor alpha induced protein 6; Tregs: regulatory T cells.


Subject(s)
Colitis , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , MicroRNAs , Animals , Autophagy/genetics , Colitis/chemically induced , Colitis/therapy , Dextran Sulfate/adverse effects , Dextran Sulfate/metabolism , Disease Models, Animal , Humans , Mice , Mice, Inbred C57BL , MicroRNAs/genetics , MicroRNAs/metabolism , Stress, Psychological
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