动物造模,动物实验 z-bio 2022-01-11 840

　　Introduction: Animal models are the key to the study of serious infectious diseases, and are of great significance to determine the pathogenesis of the disease and develop vaccines and drugs. Severe acute respiratory syndrome coronavirus (SARS-CoV), human immunodeficiency virus (HIV), Mycobacterium tuberculosis (M.tb), H7N9 influenza virus and Brucella, which can cause severe or fatal human disease and significant harm to public health. Animal experiments involving these highly infectious pathogens need to be performed in the ABSL-3 facility. There is no doubt that ensuring biosafety is the highest priority for the management of animal experiments at the ABSL-3 facility. At the same time, we cannot ignore the scientific value of animal experiments conducted in the ABSL-3 laboratory. Therefore, it is of great significance to study the key points of animal experiment management practice considering data quality under the premise of biosafety.

　　Biosafety concept: The goal of ABSL-3's animal experiment management is to ensure reliable animal experiment data (scientifically reliable data) while ensuring safety. This goal has two meanings: one is "biosafety first", that is, ensuring the safety of personnel, environment and animals in the experiment is the primary consideration. The second is "scientific and reliable data quality", which ensures the integrity and reliability of scientific research data, and ensures that scientific research goals are achieved based on security. Both "biosafety" and "quality of scientifically sound data" should be considered. Therefore, we need to first establish a holistic view of biosecurity that ensures the safety of animal experiments, and then optimize animal care and research procedures to obtain reliable, scientifically sound data from animal experiments. The overall biosafety concept needs to follow the following principles:

　　Combination of biosafety and animal welfare: Animal welfare is closely related to scientific quality, and good animal welfare conditions are conducive to the reliability of scientific data. The welfare of experimental animals requires animals to provide living conditions according to their own nature while achieving research purposes, so as to reduce the stress and pain of animals in experiments as much as possible, so as to maintain physical and mental health. Reducing stress and pain in animals can reduce aggression, reduce aerosol contamination, and animal scratches and bites, making workers safer. When their physical and mental health is maintained, stress responses to the environment and operations are minimized. Therefore, they have more stable physiological and biochemical indicators, and the results of animal experiments are more reliable.

　　Combining biosafety with experimental manipulation: Non-human primates (NHPs) are one of the most useful laboratory animals for human pathogen infection experiments in the ABSL-3 laboratory. However, unlike general commercial mouse biological isolation cages (IVCs), NHP animal cages sometimes need to be customized according to experimental requirements. Under the premise of considering biosafety, customized NHP cages should be designed according to the requirements of animal welfare and ease of operation. Animal biological isolation cages make animals difficult to care for and handle and are not suitable. Personal Protective Equipment (PPE) is the main barrier to protect workers. PPE worn in ABSL-3 facilities may limit workers' vision and reduce haptics. . These limitations reduce worker accuracy. As a result, when workers use needles and other sharp tools for surgery, their chances of injury increase. Therefore, standard operating procedures (sops) and training plans should be optimized according to the specific requirements of personal protective equipment, to improve the accuracy and stability of operations, and to ensure "biosafety" and "scientifically reasonable data quality." The following are the main safety issues and factors affecting the results of ABSL-3 animal experiments. On this basis, the main points of management practice are put forward.

　　Major safety concerns within the ABSL-3 facility: Safety concerns for laboratory animals: When cage lids or cage doors are not properly locked, infectious animals may escape, posing potential hazards to humans and the environment. Zoonotic Diseases: Zoonotic infectious pathogens carried in animals are potentially hazardous to workers. For example, the herpes virus type B is commonly carried in macaques and infected animals are asymptomatic. However, herpes B virus is lethal to humans. Scratching, biting, and kicking of animals: Some invasive procedures are prone to overreaction if the animal is not adequately sedated with analgesics or anesthetics. Workers can be scratched and bitten by infected animals. When entering a room, staff may intrude into the animal's safe "flying distance" and make the animal feel trapped and unable to escape, especially in ABSL-3 confined spaces. In this case, the animal may exhibit aggressive behavior such as biting, scratching, and kicking at people.

　　Safety issues of pathogenic microorganisms: Infectious aerosols: Infectious aerosols are easily generated from infected animal skins, furs and bedding during animal handling, cage changing, litter dumping, etc. These infectious aerosols are potentially hazardous to workers and the environment. Sharps Injuries: Sharp instruments such as needles, knives, and scissors are commonly used in animal surgery, including but not limited to blood collection, sampling, biopsy, biopsy, anesthesia, euthanasia, and autopsy. Workers can be injured by contaminated sharps and exposed to pathogens. Infectious materials for live testing and autopsies: During live testing and autopsies, workers may be exposed to zoonotic materials such as blood, urine, feces, nasopharyngeal swabs, samples containing bacteria or viruses, body fluids, and infected animals. organ. These infectious substances are potentially hazardous to workers and the environment. Wastes such as animal litter, pathogen-containing media, and carcasses of infected animals have a high potential to expose people and the environment to pathogenic microorganisms.

　　Spills and splashes of infectious substances: When laboratory workers inadvertently leak or splash on benches or on the ground, infectious substances can pose a biosafety hazard to people and the environment. Transport of infectious disease samples: Some samples collected from infected animals can be evaluated in ABSL-3, others need to be transferred out of ABSL-3 for testing. Failure to safely transfer samples from ABSL-3 poses a potential hazard to both people and the environment. Transfer of animals between rooms within ABSL-3: Infected animals sometimes need to be transferred from the animal room to a specific operating room or autopsy room within ABSL-3 for the relevant biopsy or necropsy. During animal transport, people and the environment may be exposed to pathogens. Personal Safety Issues: In some experiments, special equipment such as X-ray, PET/CT or MRI units can be set up inside the ABSL-3 unit. Such equipment produces ionizing or radioactive radiation, and we cannot ignore the associated physical safety concerns. Ionizing radiation damage: X-rays, CT, and other imaging devices are used to provide in vivo imaging data during animal experiments. For example, in monkey models studying SARS-CoV, both chest X-rays and CT scans can provide images of lung lesions. Workers exposed to X-rays from imaging equipment may be at risk for skin, hematopoietic and intestinal damage.

　　Radioactive hazards: As a biological and molecular imaging method, PET/CT scanning can non-invasively, quantitatively and dynamically monitor in vivo labeled compounds, functional information of specific organs or diseased tissues, and biological and biochemical changes in animals. It is because of these advantages that PET/CT imaging is increasingly used in animal research on infectious diseases. However, the animals needed to be injected with a radiolabeled tracer used for PET/CT scans. Therefore, animal litter, excrement and carcasses may contain radioactive material. These materials are a risk to people and the environment.

　　Anesthesia issues: Anesthetics are often used in animal experiments. Anesthetics are also harmful to human health. As an inhalation anesthetic, isoflurane has been widely used in animal experiments due to its excellent anesthetic quality. However, if workers are exposed to waste anesthetic gases, it can lead to health problems. Safety issues arising from inadequate facilities and equipment: Primary barriers include laboratory safety equipment such as biological safety cabinets (BSC), animal isolators, and personal protective equipment (PPE). Workers are protected or isolated by primary barriers to pathogens, infectious substances and infected animals.

　　Factors affecting the results of animal experiments: The animals themselves: Different animals have different characteristics in anatomy and pathophysiology. Different species respond differently to the test material. The sex, age, weight, and physical health of the animal can also affect the experimental results. Healthy laboratory animals tolerate various stimuli better than unhealthy animals. Animal breeding environment and nutritional factors: Animal breeding environmental factors, including temperature, humidity, ventilation rate, air cleanliness, light, noise, etc., have an impact on the health of experimental animals. If the animals involved in the experiment are malnourished, the results will be unreliable. Worker proficiency and technical procedures involving laboratory animals.

　　ABSL-3 Key elements of animal laboratory management practices: training and experience of project team members; worker health and safety; disposal of animal carcasses and waste; laboratory management practices; sourcing healthy laboratory animals from qualified laboratory animal suppliers ; Setting up quarantine and domestication periods for laboratory animals; scientific care of laboratory animals; preventing infected animals from escaping; setting up devices to prevent wild rodents from entering the facility;

　　Safety management practices: pathogenic microorganism safety management; personnel access management; prevention of infectious aerosols; safe use of sharp objects; avoidance of animal bites or scratches; development of good standard operating procedures for animal experiments involving highly infectious drugs; Safe disposal of waste; emergency response; chemical safety management procedures; physical hazards safety management procedures; facility and equipment management; personnel training.

　　Conclusion: The management goal of the ABSL-3 laboratory is to ensure the safety of animal experiments with highly infectious drugs and obtain high-quality experimental data. To achieve this, we need to develop a comprehensive biosafety concept that includes both a comprehensive consideration of safety (workers, environment) and a comprehensive consideration of data quality. These two aspects are critical for the successful implementation of animal experiments on ABSL-3. Comprehensive measures should be taken to do a good job in AUP review, laboratory animal management, laboratory safety management, facility and equipment management, and personnel training. These measures can not only ensure the safety of ABSL-3, but also ensure the results of scientific animal experiments.