The B7-H4 molecule, a unique negative regulator of T lymphocytes which is overexpressed on the surface of various tumorcells, is a particularly important target candidate for tumor therapy because it can be blocked with anti-B7-H4 antibodies toinhibit the B7-H4 signaling pathway. Our previous work established an anti-B7-H4 single-chain variable fragment (scFv)library, so we have now amplified the genes encoding anti-B7-H4-scFv and human IgG1 CH3 and ligated them by overlapextension PCR to obtain a recombinant gene. After sequencing, the gene was cloned into the expression vector pET43.1aand expression was induced in E. coli BL21 (DE3) by isopropyl-b-D-1-thiogalactopyranoside (IPTG). The protein waspurified on a nickel-nitrilotriacetic acid (Ni-NTA) resin column and its antigen specificity and affinity were examined byELISA and western blotting. We also established a Lewis lung cancer model in C57BL/6 mice to further identify thebiological function of the scFv protein in vivo. The results showed that tumor volume, body weight and necrotic tissues inthe control group were significantly greater than in the experimental group, indicating that selected scFvs had goodbiological activity and could inhibit tumor growth in tumor-bearing mice. Our work thus offers a new approach for thedevelopment of cancer-targeted therapy.

miRNAs are important regulatory components involving in many biological processes, including plantdevelopment, vegetative and reproductive growth, and stress response. However, identification and characterizationof miRNAs still remain limited for conifer species. In this study, with deep sequencing, we obtained1,314,450 unique reads with 18–30 nt length from a stress-tolerant conifer, Sabina chinensis. We identified 37conserved and 103 novel miRNAs, their unique characteristics were further analyzed, and 10 randomlyselected were validated by qRT-PCR. Through miRNA target predictions and annotations, we found miRNAmay have several targets as well a target could be regulated by several miRNAs, and a total of 2,397 mRNAswere predicted to be targets of the 140 miRNAs. These targets included not only important transcription factorssuch as auxin response factors, but also indispensable non-transcriptional factor proteins. Pathway-basedanalysis showed that S. chinensis miRNAs are involved in 172 metabolic pathways, of which 3 were discoveredin adaptation-related pathways, indicating their possible relevance to the species’ stress-tolerancecharacteristics. This study is expected to lay the foundation for exploring the regulative roles of miRNAs indevelopment, growth, and response to environmental stresses of S. chinensis.