Establishment And Studies Of A Whole Process Quality Control System For Biobank

“Biobank” is a facility which collects,process and store biological specimens to support translational medical research.The operation of biobank usually contains two parts of work:(I)the collection of biological material;(II)the establishment of database.As a resource integrating the biological material and database,biobank links basic research with clinical practice and has been the foundation and guarantee of translational medical research.Quality is the key to biobank.There may be concealed danger of sample quality,quantity and category,if scientific study was not conducted at the beginning of biobank construction or samples were casually collected,handling and preserved.Therefore,it should be considered how to achieve standardized construction and scientific management of biobank and to establish the whole process quality control system,in order to offer high quality resource to translational medical research.The whole process quality control system of biobank consists of quality control(QC)at the original stage and the processing stage.The QC at the original stage includes standards for sample collection process,collection method,information acquisition and sample type,etc,which should be co-determined by both clinicians and biobankers through discussion before sample collection.The QC at the processing stage includes standards for sample handling,sample storage and regularly quality test,etc,which should follow the standard operating procedures.The first part of the study aimed at the QC at the original stage.Firstly,the “one disease one card” management system was established before the sample collection.Then,we retrospectively analyzed the variation tendency of disease category,donor number and inventory sample quantity in different stages: before the application of “one disease one card” management system,the initial stage and the mature stage after its application.Furthermore,the effect of this system on biobank management was studied.As the results display,the “one disease one card” management system,in which clinicians and basic medical researchers discuss together to define the category,number,as well as the collecting and delivering procedure of the samples according to the research purpose of the specific disease,will help to ensure the scientification and standardization of sample collecting and delivering,to ensure the sample quality at the original stage and to improve the work efficiency of biobank.The second part of the study aimed at the QC at the processing stage.There are varieties of handling methods for biologic samples and the QC system involves many steps.Using RNAlater for tissue sample processing is a constant pretreatment method.Previous studies has proved that RNA inside tissue samples could be well preserved by RNAlater,however,its effect on protein and morphology of tissues need to be defined.In this study,we evaluated the preservative effect of RNAlater on different tissues,including liver,kidney,testis,brain and colon tissues from mice,by biomolecular and histological analysis.Our results revealed that high quality nucleic acids(RNA and DNA)could be obtained and tissue morphology conserved when tissues are preserved with RNAlater.However,we observed significant protein degradation in brain tissue preserved by RNAlater compared to fresh and snap-frozen tissue,while protein expression of the other four tissues was similar among the three groups.The result indicated that there were tissue-specific differences in protein preservation when using RNAlater,which should be evaluated prior to extensive storage.We explored the quality control on the management of biobank at both original and processing stage,and preliminarily established the whole process quality control system.The knowledge and skills obtained from the current study will help me to collect biologic samples roundly,scientifically and prospectively in the future clinical work,which will provide high quality resource to translational and precision medical research.Part Ⅰ : The establishment and application of the quality control system of biobank at the original stage based on the “one disease one card” management system [Object] There are various of problems at the sample collecting stage of biobank,such as the non-uniform sample collection standards in different clinical departments,the incomplete sample types,the improper sample amounts and the low work efficiency.To resolve these problems,biobankers intend to establish the “one disease one card” management system according to the research purpose of the specific disease so as to define the collecting procedure,improve work efficiency and ensure the sample quality at the original stage.Additionally,to verify the effect of the “one disease one card” system and the necessity of the quality control system at the original stage,the variation tendency of the biobank work efficiency in different stages will be retrospectively analyzed.[Methods](1)Design the disease-specific information card for clinical samples collection and transportation: clinicians and basic medical researchers discuss together to define the category,number,as well as the collecting and delivering procedure of the samples according to the research purpose of the specific disease,and the information was summarized as a tabulated form.(2)Establish and carry out the “one disease one card” management system: based on the disease-specific information card,standardized operating procedures were formulated and then critically implemented by clinicians and biobankers.(3)Analyze the variation tendency of the work efficiency of biobank: disease category,donor number and inventory sample amount in different stages(before the application of “one disease one card” management system,the initial stage and the mature stage after its application)were summarized retrospectively,as well as the variation tendency of the three indices.(4)Quality tests were conducted regularly: random sampling of inventory samples were conducted,and drawn samples were entrusted to third-party unit for quality tests.[Results](1)Disease-specific information cards for clinical samples collection and transportation were designed,in which the category,number,as well as the collecting and delivering procedure of the samples were defined.In addition,characteristic items of neoplastic,genetic and hematological diseases were particularly added.(2)The “one disease one card” management system was established and then carried out.Clinicians and biobankers both critically implemented the system.Therefore,the problems,such as the incomplete sample types,the improper sample amounts and the collecting and delivering procedure not meeting the requirement of quality control system,were avoided.(3)From the initiation of the biobank and before the application of the “one disease one card” system,just six disease,more than 200 samples from about 60 donors were collected;at the initial stage of the application of “one disease one card” system,the three indices all increased rapidly,with disease categories increasing to nearly 30,sample donors to more than 6,000 and samples to more than 14,000 in 2 years;over the next two years of the mature stage of the application of “one disease one card” system,the disease categories have increased to more than 30,and sample donors and sample amounts steadily increased to more than 10,000 and 30,000.(4)The quality test report provided by the third-party unit displayed that inventory samples meet quality standards.[Conclusion] The establishment and application of the “one disease one card” management system improve the standardization and normalization of sample collection and transportation process,and improve management and work efficiency.Effective quality control system has been established and sample quality was ensured at the original stage.Part Ⅱ: Evaluation and studies of the preservative effect of RNAlater on tissue samples during the quality control system at the process stage[Object] RNAlater Stabilization Solution is commonly used to process tissue samples before transporting to-80 ℃ freezers in biobank.However,the preservative effect of RNAlater on protein and morphology of tissues remains poorly described.Our aim was to evaluate the preservative effect of RNAlater on different types of tissues by biomolecular and histological assessment,in order to guide the correct storage of tissue samples and provide theoretical basis to acquire high quality samples.[Methods](1)Tissues collected from five different organs(liver,kidney,testis,brain and colon)of healthy mice were respectively divided into three groups as follows:(1)Fresh group(F),fresh tissues without pretreatment(as standard control);(2)RNAlater group(RL),after collection,tissues were submerged in RNAlater at 4℃ overnight followed by transferred to-80℃ freezers;(3)Liquid nitrogen group(LN),tissues were snap-frozen and maintained in liquid nitrogen after collection.(2)Subsequently,biomolecules(RNA,DNA and protein)were extracted and tissues of each group were formalin-fixed and paraffin-embedded under the same procedure.(3)The stability of tissues in three groups was assessed by biomolecules quality and morphology changes.The yield,purity and integrity of nucleic acids were assessed,as well as protein expression and hematoxylin and eosin(HE)staining results were analyzed[Results](1)High quality nucleic acids were extracted from all tissues preserved by RNAlater,exhibiting similar yield,purity and integrity comparing to fresh and snap-frozen group.Gene expression of all studied tissues determined by q RT-PCR analysis showed no major difference in three groups.(2)Notably,the brain sample in RNAlater group displayed significant protein degradation comparing to the brain tissue in fresh and liquid nitrogen groups,while the protein expression in liver,kidney,testis and colon tissues was similar among three groups.(3)The HE staining results displayed no apparent difference among three groups regarding five types of tissues.[Conclusion](1)High-quality nucleic acids and morphology can be prepared from various types of tissues preserved by RNAlater.When liquid nitrogen or ultra-low temperature freezers are not available on-site,tissue samples can be submerged in RNAlater at 4℃ overnight followed by transferred into–80℃ freezers and the quality is suitable for subsequent analysis.(2)However,tissue-specific differences are exhibited in preservative effect of RNAlater on proteins.Before processing different types of tissue samples,we suggest that small scale test should be conducted prior to extensive storage of biological samples.