Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
May 2011
Aim: To observe the effects of NK cells stimulated with immobilized MHC class I chain-related antigen A (iMICA) on activities of dendritic cells (DCs).
Methods: Firstly fresh allogeneic NK cells, or iMICA-stimulated allogeneic NK cells, and autologous NK cells stimulated with IL-2 or IL-2 and iMICA were co-cultured with immature DCs (iDCs) at the ratio of 5:1 for 24 hours. Frequencies of HLA-DR positive or CD86 positive DCs were detected by flow cytometry.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
January 2011
Aim: To observe whether MHC class I chain-related antigen A (MICA) was expressed on monocytes, immature dendritic cells (iDCs), and mature dendritic cells (mDCs), and to study effect of up-regulation of MICA expression by DCs on biologic activity of NK cells.
Methods: MICA expression on monocytes, iDCs, or mDCs stimulated with LPS, TNF-α, CD40L, IL-15 or IFN-α was detected by flow cytometry. Next CD69 expression, degranuation, and IFN-γ production of NK cells stimulated with MICA-positive mDCs were analyzed.
Major histocompatibility complex (MHC) class I chain-related protein A (MICA), which is a ligand for human NKG2D, is expressed by a variety of epithelial tumor cells and promotes the activation of natural killer (NK), CD8(+) and γδ-T cells. Although ectopic expression of MICA on tumor cells elicits anti-tumor responses, soluble MICA downregulates the activities of lymphocytes. In this study, we showed that recombinant, immobilized MICA (iMICA) molecules coated on plastic wells weakly promote peripheral NK cell activation, secretion of interferon (IFN)-γ and degranulation without inducing apoptosis.
View Article and Find Full Text PDFZhonghua Yi Xue Yi Chuan Xue Za Zhi
June 2010
Objective: To investigate whether the major histocompatibility complex class I chain-related gene A gene (MICA) polymorphism and serum soluble MICA level were associated with the occurrence and development of colorectal cancer.
Methods: DNA samples from 117 colorectal cancer patients and 113 healthy individuals from Yangzhou in Jiangsu province were genotyped by using the polymerase chain reaction (PCR) and sequence-specific primer (SSP) method and PCR based sequencing. In addition, polymorphism at position 129 was also analyzed by PCR-SSP.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
October 2009
Aim: To study the effects of recombinant soluble MHC class I chain-related protein A (sMICA) on the cytotoxicity, secretion of IFN-gamma, proliferation and apoptosis of peripheral NK cells.
Methods: After NK cells were co-cultured with recombinant soluble MICA proteins overnight, the cytotoxicity of NK cell on target cells was detected by flow cytometry. The supernant was collected to determine the concentration of IFN-gamma by ELISA.