Objective To compare the diversity of mitochondrial genomes of Angiostrongylus cantonensis in the mainland of China. Methods According to the population genetic of A. cantonensis,seven female worms were selected to characterize the mi-tochondrial(MT)genomes. Twelve primer pairs based on known MT genome(GQ398121)were used for PCR. The target frag-ments were sequenced and aligned. The gene localization,genome structure,composition of nucleotide,distribution of variable sites,and phylogeny were analyzed by employing multiple softwares. Results Five distinct types were identified from seven com-plete MT genomes. They were similar in size and structure,i.e.,ranging 13 491-13 502 bp,including 12 protein-coding genes,2 ribosomal genes,22 tRNA genes,and 2 major non-coding regions. All the genes were localized at the same strand and had the same transcription direction. A total of 745 variable sites were identified,accounting for 5.5%. Among the variable sites,59 were deletion/insert mutations,105 transversions,and 581 transitions. The variable sites distributed evenly at the complete genome. Conclusion The study reveals the mutation profile in the whole MT genome of A. cantonensis and thus will facilitate the develop-ment of intraspecific differential diagnosis.

Phage antibody display technology is currently the most widely used in vitro antibody screening technology,which uses bacteriophages as a vector,and inserts exogenous antibody library genes into phage capsid protein genes,and expresses the capsid protein on the phage surface while also displays the antibody protein.Antibody drugs play an important role in tumor immunity and microbial immunity due to their targeting advantages,which is also an important driving force for them to become a hot spot in the field of pharmaceutical research and development.Therefore,this article reviews the background,basic principles,antibody library types and antibody fragment types of phage display technology,and looks forward to the latest progress and application prospects of fully human antibodies.