病毒性减毒活疫苗感染性滴度保存的热力学方向与限度

The thermodynamics stabilization tendency and limit for the infectious titer of an attenuated virus vaccine

婴幼儿期是人一生中的生理免疫无能时期,病毒感染会威胁到新生儿的生存,仅1次自然感染即可能导致死亡.有效的疫苗接种对阻止这种结局的发生,提供了肯定性的免疫保护作用.这种针对自然病毒感染提供的特异性免疫保护作用是抗原依赖性的,活苗的免疫接种,则主要依赖于其感染性滴度.感染性滴度,指单位人份疫苗中含有的具感染性病毒颗粒个体的总数,是衡量病毒性减毒活苗有效性最重要的生物学指标.在很多情况下,病毒感染性因自身具有自发丢失性质而难以保存,这种不稳定性质在客观上对宿主的受免疫保护效果,包括以感染复制为基础的疫苗大规模病毒培养生产过程,都潜存极大的负面影响.从病毒感染的分子生物学机理及生物大分子热力学性质视角,对病毒感染性(滴度)的稳定性本质、稳定化方向及限度进行了必要探索.

Infancy and childhood is a period in one's life when he is physiological disimmunocompetence. Viral infection might imperil his life, and only once infection may cause him to die. Active vaccination can supply immunization protection in the affirmative and prevents the outcome from death. The specific immunization protection against natural viral infection depends upon antigens. For an attenuated virus vaccine, the specific protection depends upon its infectious titer. The infectious titer means the quantity of individual infectious virus contained in a dosage of an attenuated virus vaccine, which is the most important biological index for this kind of vaccines. In most cases, the infectious properties of virus will be lost spontaneously and is too difficult to keep over a long period of time. The instability of the infectious properties influences extremely on the actual immunization effect of a final host, including what based on the virus infectious properties - the virus culture process for vaccine production and their storage procedures, etc. By means of the essential mechanism of the molecular biology of viral infection and the thermodynamics properties of the biomacromolecules, this article studied the stability s essence of the viral infection properties, its stabilizing tendency and limit.