转基因植物疫苗研究进展

众多研究表明,病毒的抗原决定簇及细菌毒素亚单位均能在转基因植物中成功表达,并保持良好的免疫原性.与现有的疫苗生产体系相比,植物生产疫苗具有安全、经济、稳定、高效等优势.本文概述了利用不同受体植物生产疫苗的研究现状、免疫原性评价及免疫原基因的优化表达策略.     

Ovipositional response ofHelicoverpa armigera to different cotton genotypes

The ovipositional response ofHelicoverpa armigera (Hübner) to different cotton varieties and species was studied under caged conditions. Maximum oviposition (51.6 eggs/female) was recorded on LH 900, a variety ofGossypium hirsutum, and minimum oviposition (3.0 eggs/female) on G 27, a variety ofG. arboreum. Oviposition, in general, was low (3 to 6.5 eggs/female) onarboreum cottons as compared withhirsutum. Of the number of factors found to affect the oviposition ofH. armigera, the trichome length on the upper surface of the leaf, rather than the density, was positively correlated (r = 0.687*). Among different months in the cropping season, oviposition was maximum (552.7) during April. Oviposition was higher on leaves than on other plant parts.     

The Pattern of Enteroviral Infections in a Herd of Swine

Twenty-six pigs from four litters in a healthy herd of swine were examined periodically for the fecal excretion of viruses by the use of porcine kidney cell cultures. Viruses were initially isolated from all pigs between 34 to 64 days of age. The pigs within each litter began shedding virus in their feces approximately at the same time, usually within one week, and the type of virus initially recovered was usually the same. Subsequently, waves of infection with different enteroviruses appeared to occur during the observation period of six months. At least six antigenically different viruses were isolated from this herd over a 26-month period. Most, if not all, of these viruses were considered to belong to the enterovirus group. No disease was associated with these enteroviral infections.

The colostrum and milk of sows contained significant amounts of enteroviral antibodies. Prior to nursing, the serum of new-born pig contained no enteroviral antibodies but, shortly after nursing, high titers of such antibodies were present in the serum. Antibodies were detected in the feces of suckling pigs.