The Calcium Integrin Binding protein (CIB) has been identified as interacting specifically with the cytoplasmic tail of the integrin αIIb domain to induce receptor activation and integrin αIIbβ3 mediated cell adhes...The Calcium Integrin Binding protein (CIB) has been identified as interacting specifically with the cytoplasmic tail of the integrin αIIb domain to induce receptor activation and integrin αIIbβ3 mediated cell adhesion to extracellular proteins. In K562 cells stably expressing mutated integrin αVβ3 or chimeric αVβ3 carrying αIIb cytoplasmic tail, we report that the interaction of CIB with β3 integrins is not αIIbβ3 specific but binds αIIb as well as αV cytoplasmic tail domains. A double mutation of two proline residues to alanine residues in the αIIb cytoplasmic domain, previously shown to disturb its conformation, inhibits chimeric αV/αIIbβ3-CIB interaction. This demonstrates that αIIb cytoplasmic domain loop-like conformation is required for interaction with CIB. Moreover, mutations of β3 cytoplasmic domain residues Tyr-747 and/or Tyr-759 to phenylalanine residues (Y747F, Y759F, and Y747,759F) as well as residues Ser-752 to proline or alanine (S752P and S752A), do not affect the αIIbβ3 or αVβ3 interaction with CIB. Since tyrosine residues Tyr-747 and/or Tyr-759 are the sites of tyrosine phosphorylation of β3 subunit, these results suggest that the β3 integrin-CIB interaction occurs through aβ3-phosphorylation independent mechanism. Likewise, ablation of conformation-dependent affinity change in β3 Ser752Pro mutation had no affect on CIB-β3 interaction. In summary, our results demonstrate that the αIIb-subunit integrin and CIB interaction is non-exclusive and requires the loop-like αIIb-cytoplasmic domain conformation. An interaction of CIB with αV-containing integrins provides an additional role for this molecule in keeping with its expression outside of platelets.展开更多
Leukocyte activation has been linked to atherogenesis, but there is little in vivo evidence for its role in the progression of atherosclerosis. We evaluated the predictive value for progression of coronary artery dise...Leukocyte activation has been linked to atherogenesis, but there is little in vivo evidence for its role in the progression of atherosclerosis. We evaluated the predictive value for progression of coronary artery disease （CAD） of leukocyte activation markers in the coronary circulation. Monocyte and neutrophil CDllb, neutrophil CD66b expression and intracellular neutrophil myeloperoxidase （MPO） in the coronary arteries were determined by flow cytometry in patients undergoing coronary angiography. The primary outcome included fatal and nonfatal myocardial infarction or arterial vascular intervention due to unstable angina pectoris. In total 99 subjects who were included, 70 had CAD at inclusion （26 patients had single-vessel disease, 18 patients had two- vessel disease and 26 patients had three-vessel disease）. The median follow-up duration was 2242 days （interquartile range： 2142-2358）. During follow-up, 13 patients （13%） developed progression of CAD. Monoeyte CDllb, neutrophil CDllb and CD66b expression and intraceilular MPO measured in blood obtained from the coronary arteries were not associated with the progression of CAD. These data indicate that coronary monocyte CDllb, neutrophil CDllb and CD66b expression and intracellular MPO do not predict the risk of progression of CAD.展开更多
Inflammation and thrombosis usually occur together in many diseases,such as cardiovascular disease(CVD)and stroke,which remain to be the mostdetrimental human health killers.The crucial relevant cellular and molecular...Inflammation and thrombosis usually occur together in many diseases,such as cardiovascular disease(CVD)and stroke,which remain to be the mostdetrimental human health killers.The crucial relevant cellular and molecular events include platelet-leukocyte interaction,platelet P-selectin secretion of activated platelet and activation of leukocyte integrin Mac-1(also known asαMβ2 or CD11b/CD18),which has binding site of platelet receptor glycoprotein lbα(GPlboα). Circulating leukocytes tethered to,rolled on and firmly adhered at the activated platelets on vascular wall,through interaction of platelet P-selectin with leukocyte P-selectin glycoprotein ligand-1(PSGL-1)and Mac-1 with GPlbα.We assume that there is a rapid signaling pathway in PSGL-1 ligation-induced activation of Mac-1,for forming a stable gap junction intracellular communication between platelet and leukocyte.To test this assumption,we observed the tethering events and calcium bursting of neutrophils on immobilized P-selectin only or plus GPlbαwith use of the parallel plate flow chamber(PPFC)technique and intracellular calcium ion detector Fluo-4 AM at various wall shear stresses,and examined the dynamic force spectrum for interaction of Mac-1 plus Mn2+and GPlbαby single-molecule atomic force microscopy(AFM).In the PPFC experiments,the intracellular calcium flux of firmly adhered neutrophils on immobilized P-selectin only or plus GPlbαwas observed in real timeby fluorescence microscopy,and the tether events of neutrophils was recorded by an inverted microscope and a high speed CMOS acquisition system in 1280 pixels×1024 pixels at 100 frames per second(fps). Captured images were analyzed by Image Pro Plus.Our results indicated that force triggered,enhanced and quickened the cytoplasmic calcium bursting of neutrophils.Calcium bursting may be induced first by interaction of the activated neutrophil Integrin Mac-1 and GPlbα,but not by P-selectin ligation to its ligand PSGL-1.Being triggered and speeded up by wall shear stress,the P-selectin-induced a展开更多
Tenascin-C(TNC)is an adhesion modulatory protein present in the extracellular matrix that is highly expressed in several malignancies,including colon cancer.Although TNC is considered a negative prognostic factor for ...Tenascin-C(TNC)is an adhesion modulatory protein present in the extracellular matrix that is highly expressed in several malignancies,including colon cancer.Although TNC is considered a negative prognostic factor for cancer patients,the substantial role of the TNC molecule in colorectal carcinogenesis and its malignant progression is poorly understood.We previously found that TNC has a cryptic functional site and that a TNC peptide containing this site,termed TNIIIA2,can potently and persistently activate beta1-integrins.In contrast,the peptide FNIII14,which contains a cryptic bioactive site within the fibronectin molecule,can inactivate beta1-integrins.This review presents the role of TNC in the development of colitis-associated colorectal cancer and in the malignant progression of colon cancer,particularly the major involvement of its cryptic functional site TNIIIA2.We propose new possible prophylactic and therapeutic strategies based on inhibition of the TNIIIA2-induced beta1-integrin activation by peptide FNIII14.展开更多
基金Research from the corresponding author’s laboratory was supported by the National Natural Science Foundation of China(No.31525016,31190061,31271487,31471309,31970702,and 31701219)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2020266)the Young Elite Scientist Sponsorship Program by China Association for Science and Technology(No.2019QNRC001)。
文摘The Calcium Integrin Binding protein (CIB) has been identified as interacting specifically with the cytoplasmic tail of the integrin αIIb domain to induce receptor activation and integrin αIIbβ3 mediated cell adhesion to extracellular proteins. In K562 cells stably expressing mutated integrin αVβ3 or chimeric αVβ3 carrying αIIb cytoplasmic tail, we report that the interaction of CIB with β3 integrins is not αIIbβ3 specific but binds αIIb as well as αV cytoplasmic tail domains. A double mutation of two proline residues to alanine residues in the αIIb cytoplasmic domain, previously shown to disturb its conformation, inhibits chimeric αV/αIIbβ3-CIB interaction. This demonstrates that αIIb cytoplasmic domain loop-like conformation is required for interaction with CIB. Moreover, mutations of β3 cytoplasmic domain residues Tyr-747 and/or Tyr-759 to phenylalanine residues (Y747F, Y759F, and Y747,759F) as well as residues Ser-752 to proline or alanine (S752P and S752A), do not affect the αIIbβ3 or αVβ3 interaction with CIB. Since tyrosine residues Tyr-747 and/or Tyr-759 are the sites of tyrosine phosphorylation of β3 subunit, these results suggest that the β3 integrin-CIB interaction occurs through aβ3-phosphorylation independent mechanism. Likewise, ablation of conformation-dependent affinity change in β3 Ser752Pro mutation had no affect on CIB-β3 interaction. In summary, our results demonstrate that the αIIb-subunit integrin and CIB interaction is non-exclusive and requires the loop-like αIIb-cytoplasmic domain conformation. An interaction of CIB with αV-containing integrins provides an additional role for this molecule in keeping with its expression outside of platelets.
文摘Leukocyte activation has been linked to atherogenesis, but there is little in vivo evidence for its role in the progression of atherosclerosis. We evaluated the predictive value for progression of coronary artery disease （CAD） of leukocyte activation markers in the coronary circulation. Monocyte and neutrophil CDllb, neutrophil CD66b expression and intracellular neutrophil myeloperoxidase （MPO） in the coronary arteries were determined by flow cytometry in patients undergoing coronary angiography. The primary outcome included fatal and nonfatal myocardial infarction or arterial vascular intervention due to unstable angina pectoris. In total 99 subjects who were included, 70 had CAD at inclusion （26 patients had single-vessel disease, 18 patients had two- vessel disease and 26 patients had three-vessel disease）. The median follow-up duration was 2242 days （interquartile range： 2142-2358）. During follow-up, 13 patients （13%） developed progression of CAD. Monoeyte CDllb, neutrophil CDllb and CD66b expression and intraceilular MPO measured in blood obtained from the coronary arteries were not associated with the progression of CAD. These data indicate that coronary monocyte CDllb, neutrophil CDllb and CD66b expression and intracellular MPO do not predict the risk of progression of CAD.
基金supported by the National Natural Science Foundation of China ( 116272109,11432006)
文摘Inflammation and thrombosis usually occur together in many diseases,such as cardiovascular disease(CVD)and stroke,which remain to be the mostdetrimental human health killers.The crucial relevant cellular and molecular events include platelet-leukocyte interaction,platelet P-selectin secretion of activated platelet and activation of leukocyte integrin Mac-1(also known asαMβ2 or CD11b/CD18),which has binding site of platelet receptor glycoprotein lbα(GPlboα). Circulating leukocytes tethered to,rolled on and firmly adhered at the activated platelets on vascular wall,through interaction of platelet P-selectin with leukocyte P-selectin glycoprotein ligand-1(PSGL-1)and Mac-1 with GPlbα.We assume that there is a rapid signaling pathway in PSGL-1 ligation-induced activation of Mac-1,for forming a stable gap junction intracellular communication between platelet and leukocyte.To test this assumption,we observed the tethering events and calcium bursting of neutrophils on immobilized P-selectin only or plus GPlbαwith use of the parallel plate flow chamber(PPFC)technique and intracellular calcium ion detector Fluo-4 AM at various wall shear stresses,and examined the dynamic force spectrum for interaction of Mac-1 plus Mn2+and GPlbαby single-molecule atomic force microscopy(AFM).In the PPFC experiments,the intracellular calcium flux of firmly adhered neutrophils on immobilized P-selectin only or plus GPlbαwas observed in real timeby fluorescence microscopy,and the tether events of neutrophils was recorded by an inverted microscope and a high speed CMOS acquisition system in 1280 pixels×1024 pixels at 100 frames per second(fps). Captured images were analyzed by Image Pro Plus.Our results indicated that force triggered,enhanced and quickened the cytoplasmic calcium bursting of neutrophils.Calcium bursting may be induced first by interaction of the activated neutrophil Integrin Mac-1 and GPlbα,but not by P-selectin ligation to its ligand PSGL-1.Being triggered and speeded up by wall shear stress,the P-selectin-induced a
文摘Tenascin-C(TNC)is an adhesion modulatory protein present in the extracellular matrix that is highly expressed in several malignancies,including colon cancer.Although TNC is considered a negative prognostic factor for cancer patients,the substantial role of the TNC molecule in colorectal carcinogenesis and its malignant progression is poorly understood.We previously found that TNC has a cryptic functional site and that a TNC peptide containing this site,termed TNIIIA2,can potently and persistently activate beta1-integrins.In contrast,the peptide FNIII14,which contains a cryptic bioactive site within the fibronectin molecule,can inactivate beta1-integrins.This review presents the role of TNC in the development of colitis-associated colorectal cancer and in the malignant progression of colon cancer,particularly the major involvement of its cryptic functional site TNIIIA2.We propose new possible prophylactic and therapeutic strategies based on inhibition of the TNIIIA2-induced beta1-integrin activation by peptide FNIII14.
