Quantitatively relating magnetic resonance T_(1)and T_(2)to glycosaminoglycan and collagen concentrations mediated by penetrated contrast agents and biomacromolecule-bound water  

作　　者：Jingming Gao Xian Xu Xiaoye Yu Ye Fu Hongjie Zhang Siyi Gu Dinglingge Cao Quanyi Guo Liming Xu Jiandong Ding 

机构地区：[1]State Key Laboratory of Molecular Engineering of Polymers,Department of Macromolecular Science,Fudan University,Shanghai 200438,China [2]Department of Radiology,The SecondMedical Center&National Clinical Research Center for Geriatric Diseases,Chinese PLA General Hospital,Beijing 100853,China [3]Institute of Orthopedics,The First Medical Center,Chinese PLA General Hospital,Beijing Key Lab of Regenerative Medicine in Orthopedics,Key Laboratory of Musculoskeletal Trauma and War Injuries of PLA,Beijing 100853,China [4]Institute for Medical Device Control,National Institutes for Food and Drug Control,Beijing 102629,China

出　　处：《Regenerative Biomaterials》2023年第1期871-888,共18页再生生物材料（英文版）

基　　金：supported by National Natural Science Foundation of China(grant no.52130302).W。

摘　　要：Magnetic resonance imaging(MRI)is a promising non-invasive method to assess cartilage regeneration based on the quantitative relationship between MRI features and concentrations of the major components in the extracellular matrix(ECM).To this end,in vitro experiments are performed to investigate the relationship and reveal the underlying mechanism.A series of collagen(COL)and glycosaminoglycan(GAG)solutions at different concentrations are prepared,and T_(1)and T_(2)relaxation times are measured with or without a contrast agent(Gd-DTPA2−)by MRI.Fourier transform infrared spectrometry is also used to measure the contents of biomacromolecule-bound water and other water,allowing theoretical derivation of the relationship between biomacromolecules and the resulting T_(2)values.It has been revealed that the MRI signal in the biomacromolecule aqueous systems is mainly influenced by the protons in hydrogens of biomacromolecule-bound water,which we divide into inner-bound water and outer-bound water.We have also found that COL results in higher sensitivity of bound water than GAG in T_(2)mapping.Owing to the charge effect,GAG regulates the penetration of the contrast agent during dialysis and has a more significant effect on T_(1)values than COL.Considering that COL and GAG are the most abundant biomacromolecules in the cartilage,this study is particularly useful for the real-time MRI-guided assessment of cartilage regeneration.A clinical case is reported as an in vivo demonstration,which is consistent with our in vitro results.The established quantitative relation plays a critical academic role in establishing an international standard ISO/TS24560-1:2022‘Clinical evaluation of regenerative knee articular cartilage using delayed gadolinium-enhanced MRI of cartilage(dGEMRIC)and T_(2)mapping’drafted by us and approved by International Standard Organization.

关 键 词：magnetic resonance imaging COLLAGEN GLYCOSAMINOGLYCAN bound water CARTILAGE 

分 类 号：R318[医药卫生—生物医学工程]