BackgroundThe microsporidian Enterocytozoon hepatopenaei was first described from Thailand in 2009 in farmed, indigenous giant tiger shrimp Penaeus (Penaeus) monodon. The natural reservoir for the parasite is still unknown. More recently, a microsporidian closely resembling it in morphology and tissue preference was found in Thai-farmed, exotic, whiteleg shrimp Penaeus (Litopenaeus) vannamei exhibiting white feces syndrome (WFS). Our objective was to compare the newly found pathogen with E. hepatopenaei and to determine its causal relationship with WFS.ResultsGeneric primers used to amplify a fragment of the small subunit ribosomal RNA (ssu rRNA) gene for cloning and sequencing revealed that the new parasite from WFS ponds had 99% sequence identity to that of E. hepatopenaei, suggesting it was conspecific. Normal histological analysis using tissue sections stained with hematoxylin and eosin (H&E) revealed that relatively few tubule epithelial cells exhibited spores, suggesting that the infections were light. However, the H&E results were deceptive since nested PCR and in situ hybridization analysis based on the cloned ssu rRNA gene fragment revealed very heavy infections in tubule epithelial cells in the central region of the hepatopancreas in the absence of spores. Despite these results, high prevalence of E. hepatopenaei in shrimp from ponds not exhibiting WFS and a pond that had recovered from WFS indicated no direct causal association between these infections and WFS. This was supported by laboratory oral challenge trials that revealed direct horizontal transmission to uninfected shrimp but no signs of WFS.ConclusionsThe microsporidian newly found in P. vannamei is conspecific with previously described E. hepatopenaei and it is not causally associated with WFS. However, the deceptive severity of infections (much greater than previously reported in P. monodon) would undoubtedly have a negative effect on whiteleg shrimp growth and production efficiency and this could be exacerbated by the possibility of horizontal transmission revealed by laboratory challenge tests. Thus, it is recommended that the PCR and in situ hybridization methods developed herein be used to identify the natural reservoir species so they can be eliminated from the shrimp rearing system.
Introduction. The Infrapatellar fat pad (IPFP) represents an emerging alternative source of adipose-derived mesenchymal stem cells (ASCs). We compared the characteristics and differentiation capacity of ASCs isolated from IPFP and SC. Materials and Methods. ASCs were harvested from either IPFP or SC. IPFPs were collected from patients undergoing total knee arthroplasty (TKA), whereas subcutaneous tissues were collected from patients undergoing lipoaspiration. Immunophenotypes of surface antigens were evaluated. Their ability to form colony-forming units (CFUs) and their differentiation potential were determined. The ASCs karyotype was evaluated. Results. There was no difference in the number of CFUs and size of CFUs between IPFP and SC sources. ASCs isolated from both sources had a normal karyotype. The mesenchymal stem cells (MSCs) markers on flow cytometry was equivalent. IPFP-ASCs demonstrated significantly higher expression of SOX-9 and RUNX-2 over ASCs isolated from SC (6.19 ± 5.56-, 0.47 ± 0.62-fold; p value = 0.047, and 17.33 ± 10.80-, 1.56 ± 1.31-fold; p value = 0.030, resp.). Discussion and Conclusion. CFU assay of IPFP-ASCs and SC-ASCs harvested by lipoaspiration technique was equivalent. The expression of key chondrogenic and osteogenic genes was increased in cells isolated from IPFP. IPFP should be considered a high quality alternative source of ASCs.
Intracellular fatty acid-binding proteins (FABPs) are small members of the superfamily of lipid-binding proteins, which occur in invertebrates and vertebrates. Included in this superfamily are the cellular retinoic acid-binding proteins and retinol-binding proteins, which seem to be restricted to vertebrates. Here, we report the cDNA cloning and characterization of two FABPs from hemocytes of the freshwater crayfish Pacifastacus leniusculus and the shrimp Penaeus monodon. In both these proteins, the binding triad residues involved in interaction with ligand carboxylate groups are present. From the sequence and homology modeling, the proteins are probably FABPs and not retinoic acid-binding proteins. The crayfish transcript (plFABP) was detected at high level in hemocytes, hepatopancreas, intestine and ovary and at low level in hematopoietic tissue and testis. Its expression in hematopoietic cells varied depending on the state of the crayfish from which it was isolated. Expression was 10-15 times higher in cultures isolated from crayfish with red colored plasma, in which hemocyte synthesis was high, if retinoic acid was added to the culture medium. In normal colored crayfish, with normal levels of hemocytes, no increase in expression of p1FABP was detected. Two other putative plFABP ligands, stearic acid and oleic acid, did not have any effect on plFABP expression in hematopoietic cells. These results suggest that retinoic acid-dependent signaling may be present in crustaceans.
Of 23 strains of halotolerant (up to 12% w/v NaCl) photosynthetic bacteria isolated from various sources, one isolate, SH5, accumulated intracellular 5-aminolevulinic acid (ALA) at 0.45 microg/g dry cell wt (DCW) growing aerobically in the dark. The strain was identified as Rhodobacter sphaeroides using 16S rDNA sequencing. Biosynthesis of ALA was enhanced to 14 microg/g DCW using modified glutamate/glucose (50 mM) medium with the addition of 10 mM levulinic acid after 24 h cultivation. Addition of 30 microM Fe(2+) to this medium increased the yield to 226 microg/g DCW.
BackgroundA key event in human development is the establishment of erythropoietic progenitors in the bone marrow, which is accompanied by a fetal-to-adult switch in hemoglobin expression. Understanding of this event could lead to medical application, notably treatment of sickle cell disease and β-thalassemia. The changes in gene expression of erythropoietic progenitor cells as they migrate from the fetal liver and colonize the bone marrow are still rather poorly understood, as primary fetal liver (FL) tissues are difficult to obtain.MethodsWe obtained human FL tissue and adult peripheral blood (AB) samples from Thai subjects. Primary CD34+ cells were cultured in vitro in a fetal bovine serum-based culture medium. After 8 days of culture, erythroid cell populations were isolated by flow cytometry. Gene expression in the FL- and AB-derived cells was studied by Affymetrix microarray and reverse-transcription quantitative PCR. The microarray data were combined with that from a previous study of human FL and AB erythroid development, and meta-analysis was performed on the combined dataset.ResultsFL erythroid cells showed enhanced proliferation and elevated fetal hemoglobin relative to AB cells. A total of 1,391 fetal up-regulated and 329 adult up-regulated genes were identified from microarray data generated in this study. Five hundred ninety-nine fetal up-regulated and 284 adult up-regulated genes with reproducible patterns between this and a previous study were identified by meta-analysis of the combined dataset, which constitute a core set of genes differentially expressed between FL and AB erythroid cells. In addition to these core genes, 826 and 48 novel genes were identified only from data generated in this study to be FL up- and AB up-regulated, respectively. The in vivo relevance for some of these novel genes was demonstrated by pathway analysis, which showed novel genes functioning in pathways known to be important in proliferation and erythropoiesis, including the mitogen-activated protein kinase (MAPK) and the phosphatidyl inositol 3 kinase (PI3K)-Akt pathways.DiscussionThe genes with upregulated expression in FL cells, which include many novel genes identified from data generated in this study, suggest that cellular proliferation pathways are more active in the fetal stage. Erythroid progenitor cells may thus undergo a reprogramming during ontogenesis in which proliferation is modulated by changes in expression of key regulators, primarily MYC, and others including insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3), neuropilin and tolloid-like 2 (NETO2), branched chain amino acid transaminase 1 (BCAT1), tenascin XB (TNXB) and proto-oncogene, AP-1 transcription factor subunit (JUND). This reprogramming may thus be necessary for acquisition of the adult identity and switching of hemoglobin expression.
The MUi019-A human induced pluripotent stem cell line was generated from peripheral blood CD34+ hematopoietic progenitors of a healthy woman using a non-integrative reprogramming method. Episomal vectors carrying reprogramming factors OCT4, SOX2, KLF4, L-MYC, LIN28, and shRNA of TP53 and EBNA-1 were delivered using electroporation. The iPSC line can be used as a control in studying disease mechanisms. Furthermore, gene editing approaches can be used to introduce specific mutations into the MUi019-A to model disease while the cell type affected by the disease is inaccessible.
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