^(11)C-PK11195 is a positron emitter tracer used for Positron Emission Tomography(PET)imaging of innate immune cell activation in studies of neuroinflammatory diseases.For the image quantitative analysis,it is necessa...^(11)C-PK11195 is a positron emitter tracer used for Positron Emission Tomography(PET)imaging of innate immune cell activation in studies of neuroinflammatory diseases.For the image quantitative analysis,it is necessary to quantify the intact fraction of this tracer in the arterial plasma during imaging acquisition(plasma intact fraction).Due to the complexity and costs involved in this analysis it is important to evaluate the real necessity of individual analysis in each 11C-PK11195 PET imaging acquisition.The purpose of this study is to compare 11CPK11195 plasma metabolization rate between healthy controls and multiple sclerosis(MS)patients and evaluate the interference of sex,age,treatment,and disease phenotype in the tracer intact fraction measured in arterial plasma samples.11C-PK11195 metabolization rate in arterial plasma was quantified by high performance liquid chromatography in samples from MS patients(n=50)and healthy controls(n=23)at 20,45,and 60 minutes after 11C-PK11195 injection.Analyses were also stratified by sex,age,treatment type,and MS phenotype.The results showed no significant differences in the metabolization rate of healthy controls and MS patients,or in the stratified samples.In conclusion,11C-PK11195 metabolization has the same rate in patients with MS and healthy controls,which is not affected by sex,age,treatment,and disease phenotype.Thus,these findings could contribute to exempting the necessity for tracer metabolization determination in all 11C-PK11195 PET imaging acquisition,by using a population metabolization rate average.The study procedures were approved by the Ethics Committee for Research Projects Analysis of the Hospital das Clinicas of the University of Sao Paulo Medical School(approval No.624.065)on April 23,2014.展开更多
The discovery of endogenous neural stem cells(e NSCs) in the adult mammalian brain with their ability to self-renew and differentiate into functional neurons, astrocytes and oligodendrocytes has raised the hope for no...The discovery of endogenous neural stem cells(e NSCs) in the adult mammalian brain with their ability to self-renew and differentiate into functional neurons, astrocytes and oligodendrocytes has raised the hope for novel therapies of neurological diseases. Experimentally, those e NSCs can be mobilized in vivo, enhancing regeneration and accelerating functional recovery after, e.g., focal cerebral ischemia, thus constituting a most promising approach in stem cell research. In order to translate those current experimental approaches into a clinical setting in the future, non-invasive imaging methods are required to monitor e NSC activation in a longitudinal and intraindividual manner. As yet, imaging protocols to assess eNSC mobilization non-invasively in the live brain remain scarce, but considerable progress has been made in this field in recent years. This review summarizes and discusses the current imaging modalities suitable to monitor e NSCs in individual experimental animals over time, including optical imaging, magnetic resonance tomography and-spectroscopy, as well as positron emission tomography(PET). Special emphasis is put on the potential of each imaging method for a possible clinical translation, and on the specificity of the signal obtained. PET-imaging with the radiotracer 3'-deoxy-3'-[18F]fluoro-L-thymidine in particular constitutes a modality with excellent potential for clinical translation but low specificity; however, concomitant imaging of neuroinflammation is feasible and increases its specificity. The non-invasive imaging strategies presented here allow for the exploitation of novel treatment strategies based upon the regenerative potential of e NSCs, and will help to facilitate a translation into the clinical setting.展开更多
基金This work was supported by GE Healthcare,No.12496139131(to DPF and CAB)。
文摘^(11)C-PK11195 is a positron emitter tracer used for Positron Emission Tomography(PET)imaging of innate immune cell activation in studies of neuroinflammatory diseases.For the image quantitative analysis,it is necessary to quantify the intact fraction of this tracer in the arterial plasma during imaging acquisition(plasma intact fraction).Due to the complexity and costs involved in this analysis it is important to evaluate the real necessity of individual analysis in each 11C-PK11195 PET imaging acquisition.The purpose of this study is to compare 11CPK11195 plasma metabolization rate between healthy controls and multiple sclerosis(MS)patients and evaluate the interference of sex,age,treatment,and disease phenotype in the tracer intact fraction measured in arterial plasma samples.11C-PK11195 metabolization rate in arterial plasma was quantified by high performance liquid chromatography in samples from MS patients(n=50)and healthy controls(n=23)at 20,45,and 60 minutes after 11C-PK11195 injection.Analyses were also stratified by sex,age,treatment type,and MS phenotype.The results showed no significant differences in the metabolization rate of healthy controls and MS patients,or in the stratified samples.In conclusion,11C-PK11195 metabolization has the same rate in patients with MS and healthy controls,which is not affected by sex,age,treatment,and disease phenotype.Thus,these findings could contribute to exempting the necessity for tracer metabolization determination in all 11C-PK11195 PET imaging acquisition,by using a population metabolization rate average.The study procedures were approved by the Ethics Committee for Research Projects Analysis of the Hospital das Clinicas of the University of Sao Paulo Medical School(approval No.624.065)on April 23,2014.
文摘The discovery of endogenous neural stem cells(e NSCs) in the adult mammalian brain with their ability to self-renew and differentiate into functional neurons, astrocytes and oligodendrocytes has raised the hope for novel therapies of neurological diseases. Experimentally, those e NSCs can be mobilized in vivo, enhancing regeneration and accelerating functional recovery after, e.g., focal cerebral ischemia, thus constituting a most promising approach in stem cell research. In order to translate those current experimental approaches into a clinical setting in the future, non-invasive imaging methods are required to monitor e NSC activation in a longitudinal and intraindividual manner. As yet, imaging protocols to assess eNSC mobilization non-invasively in the live brain remain scarce, but considerable progress has been made in this field in recent years. This review summarizes and discusses the current imaging modalities suitable to monitor e NSCs in individual experimental animals over time, including optical imaging, magnetic resonance tomography and-spectroscopy, as well as positron emission tomography(PET). Special emphasis is put on the potential of each imaging method for a possible clinical translation, and on the specificity of the signal obtained. PET-imaging with the radiotracer 3'-deoxy-3'-[18F]fluoro-L-thymidine in particular constitutes a modality with excellent potential for clinical translation but low specificity; however, concomitant imaging of neuroinflammation is feasible and increases its specificity. The non-invasive imaging strategies presented here allow for the exploitation of novel treatment strategies based upon the regenerative potential of e NSCs, and will help to facilitate a translation into the clinical setting.
