RESUMO
Single cell laser tweezers Raman spectroscopy (LTRS) has been applied to biology field. In the present article, the authors measured the spectra of liver cancer cells, para-cancer cells and normal hepatocytes using single cell laser tweezer Raman spectroscopy (LTRS) system and compared their average spectra changes. The results showed that the laser tweezers Raman spectroscopy could differentiate specimens of different pathological changes from liver tissue studied. The 1 070 and 1 266 cm(-1) peaks obtained from normal hepatocytes were more visible than the same two peaks obtained from liver cancer and para-cancer specimen. The 1 445 cm(-1) peak of normal hepatocytes was higher than that of liver cancer cells and para-cancer cells. It is known that the 1 070 cm(-1) peak represents lipids and nucleic acids, while 1 266 and 1 445 cm(-1) peaks represent lipids and proteins. So, these peak changes may directly reflect the changed biomaterials related to liver carcinogenesis. Thus, single cell laser tweezer Raman spectroscopy may be a nondestructive, rapid and good method to measure and analyze different pathological specimens from liver cancer.
Assuntos
Neoplasias Hepáticas/patologia , Pinças Ópticas , Análise Espectral Raman/métodos , Humanos , Fígado/citologia , Fígado/patologia , Análise de Componente PrincipalRESUMO
The fate of human hematopoietic stem cells (HSCs)/progenitor cells (HPCs) is influenced by bone marrow (BM) stromal cells. To investigate the role of stromal cells in the hematopoietic support, we have transduced human fetal BM stromal cells (FBMSCs) with a human telomerase catalytic subunit (hTERT). One of the resultant cell lines was identified as osteoblasts, because it contained mineral deposits and constitutively expressed osteogenic genes osteocalcin, osteopontin, collagen type I, osteoblast marker alkaline phosphatase, but not marrow stromal cell marker STRO-1 and CD105. The hTERT-transduced fetal BM-derived osteoblastic cells (FBMOB-hTERT) can actively maintain the capacity of self-renewal and multipotency of HSCs/HPCs at least partly through transcriptional up-regulation of hematopoietic growth factors such as stem cell growth factors (SCFs) and Wnt-5A during interaction with HSCs/HPCs. The enhanced transcription of SCFs and Wnt-5A appears to be mediated by CD29 signaling. Moreover, the FBMOB-hTERT cells seem superior to primary FBMSCs in supporting hematopoiesis, because they are more potent than primary FBMSCs in supporting the ex vivo expansion and long-term culture initiating cells activity of HSCs. The FBMOB-hTERT cell line has been maintained in vitro more than 125 population doublings without tumorigenicity. The results indicate that the FBMOB-hTERT is useful for the study of molecular mechanisms by which osteoblasts support hematopoiesis.
Assuntos
Células da Medula Óssea/citologia , Linhagem Celular/citologia , Hematopoese , Osteoblastos/citologia , Telomerase/genética , Animais , Células da Medula Óssea/enzimologia , Domínio Catalítico , Linhagem Celular/enzimologia , Feto/citologia , Hematopoese/genética , Fatores de Crescimento de Células Hematopoéticas/genética , Fatores de Crescimento de Células Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/enzimologia , Humanos , Camundongos , Osteoblastos/enzimologia , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Células Estromais/citologia , Células Estromais/enzimologia , Transdução Genética , Regulação para Cima , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Proteína Wnt-5a , Quinases da Família srcRESUMO
Three-dimensional (3D) culture of cells could closely mimic the in vivo situation with regard to cell function and microenvironment compared with plane monolayer cultured cells. In this paper, we established 3D culture of rat WB-F344 cells with rotary cell culture system (RCCS) to simulate microgravity environment, and examined cells proliferation, morphology, microstructure, E-cadherin protein quantity and mRNA expression of adhesion molecules by count the number of cells, optical microscope, transmission electron microscope and reverse transcriptase-polymerase chain reaction (RT-PCR). The results demonstrated that cells were polyhedron with lots of micovilli and mitochondria, which grow well and packed together densely to form irregular aggregates. Adjacent cells were connected with desmosome and tight junction. With the regard, the aggregates behaved 3D growth characteristics. Moreover, compared with control, mRNA level of Fibronectin and E-cadherin protein were increased, the changes maybe is the part mechanism in this microgravity simulated cells culture models which strengthened cells junction. This rotating 3D model might facilitate the study of interactions of cell-cell, cell-matrix and the mechanisms.
Assuntos
Técnicas de Cultura de Células/métodos , Esferoides Celulares , Simulação de Ausência de Peso , Animais , Caderinas/genética , Adesão Celular , Proliferação de Células , Fibronectinas/genética , Ratos , Esferoides Celulares/ultraestruturaRESUMO
Killer cell immunoglobulin-like receptor (KIR) 2DL4 is the only KIR member reported to be expressed by all human natural killer (NK) cells. It differs from other KIR members in both structure and function. Its specific interaction with HLA-G, a non-classical MHC class I molecule, has been suggested to play an important role in regulating NK cell-mediated cytotoxicity. However, this interaction is still in doubt. In addition, the soluble KIR2DL4 extracellular domain used in many studies was produced by eukaryotic expression, which is less efficient than prokaryotic expression. In this study, we describe a method of rapid production a large amount of soluble KIR2DL4 extracellular domain based on a prokaryotic expression system. With this soluble KIR2DL4, we verified the interaction between KIR2DL4 and HLA-G1.
Assuntos
Antígenos HLA/química , Antígenos de Histocompatibilidade Classe I/química , Receptores Imunológicos/química , Expressão Gênica , Antígenos HLA/genética , Antígenos HLA/imunologia , Antígenos HLA-G , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Células K562 , Células Matadoras Naturais/imunologia , Ligação Proteica/genética , Ligação Proteica/imunologia , Estrutura Terciária de Proteína/genética , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , Receptores KIR , Receptores KIR2DL4 , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Relação Estrutura-AtividadeRESUMO
The soluble HLA-G1 (sHLA-G1) isoform was found to be secreted by trophoblast cells at the materno-fetal interface, which suggests that it may act as an immunomodulator during pregnancy. In this paper, we reported that GST-sHLA-G1a chain could bind to its receptor ILT-2 on NK92 cells and then the latter recruited Src homology 2 domain-containing tyrosine phosphatase-1 (SHP-1), which consequently dephosphorylated some important protein tyrosine kinases and blocked the activation of downstream molecules such as MEK and ERK so that the cytotoxicity of natural killer (NK) cells was inhibited. These results indicated that GST-sHLA-G1a chain might be exploited in new immunotherapy strategies aiming at inducing immunotolerance during allograft, xenograft and autoimmune situations. In addition, we found that modification of O-linked b-N-acetylglucosamine (O-GlcNAc) was involved in NK cells' activating and inhibitory signals. This may provide a novel molecular target for inducing immunotolerance but needs further study.
Assuntos
Antígenos CD/metabolismo , Glutationa Transferase/metabolismo , Antígenos HLA/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Receptores Imunológicos/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Acetilglucosamina/imunologia , Linhagem Celular , Glutationa Transferase/genética , Glutationa Transferase/imunologia , Antígenos HLA/genética , Antígenos HLA/imunologia , Antígenos HLA-G , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Células Matadoras Naturais/imunologia , Receptor B1 de Leucócitos Semelhante a Imunoglobulina , Ativação Linfocitária/imunologia , Proteína Fosfatase 1 , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Transdução de Sinais/imunologia , Trofoblastos/imunologia , Trofoblastos/metabolismo , Domínios de Homologia de srcRESUMO
Stromal cell derived factor (SDF), expressing on bone marrow stromal cells is a CXC-type chemokine, which specifically chemoattracts hematopoietic stem cells (HSCs) expressing CXCR4. SDF plays important roles in homing and mobilizing of HSCs. In this paper the regulatory mechanism of SDF/CXCR4 in the HSC migration process is mainly reviewed.
