Retinal macrophages and (or) microglial cells play important roles in regulating inflammation,angiogenesis and tissue repairing,thus affect the development and prognosis of ischemic retinal disease,ocular immune diseases and ocular tumors.Reversing the polarization imbalance of these cells may provide new therapeutic strategies for ischemic retinal disease and ocular immune diseases.The duality of the polarization direction of these cells is still controversial in the inflammatory reaction and pathological angiogenesis of ischemic retinal disease.Meanwhile,the plasticity and diversity of the function need to be further studied and discussed.

Knockout is an important method for gene function study, while vector is the core of gene knockout. In order to obtain an effective vector for rapid construction of mutant and essentiality identification of the corresponding gene, we constructed a recombinant plasmid named plDM-T based on the temperature-sensitive and replication- defective plasmid plDM1 by inserting an Xcm I adapter into the EcoR I and Pst I sites of pIDM1. Digesting with Xcm I, pIDM-T can be prepared as a linear T-vector for PCR products cloning and be used to knockout the corresponding gene in the genome with insertion duplication mutagenesis. After the verification of temperature sensitivity of the replication of the plasmid, we cloned two Salmonella pullorum genes eno and ybdr into the constructed pIDM-T, and two recombinant plasmids pIDM-T_eno and pIDM-T_ybdr were identified. The recombinant plasmids were then transformed into S. pullorum strain CVCC527 and the IPC (Integration rate per cell) values were calculated. As a result, we identified the eno gene as an essential gene and the ybdr as a non-essential gene in CVCC527. We verified the correctness of recombination site in ybdr recombinant 527 clones (Sal delta ybdr) by PCR and sequencing. The pIDM-T vector can be used for gene knockout in S. pullorum, as well as the identification of essentiality of the corresponding genes, which offers an effective and rapid tool for gene function study in Salmonella.
Cloning, Molecular ; Gene Knockout Techniques ; Genetic Vectors ; genetics ; metabolism ; Plasmids ; genetics ; Recombinant Proteins ; genetics ; metabolism ; Recombination, Genetic ; Salmonella ; classification ; genetics