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Objective To investigate the role of tumor draining lymph nodes (TDLN) in the generation of memory CD8+ T cells under the context of neoadjuvant anti-PD-L1 therapy. Methods A mouse transplanted model of CT26/MC38-OVA colon cancer was established to recapitulate clinic neoadjuvant anti-PD-L1 therapy, and then the tumor masses and TDLN were removed in 15 d after transplantation. On day 30 after surgery, the effect of TDLN on the formation of immune memory was assessed under the condition of neoadjuvant PD-L1 antibody therapy by tumor re-challenge. The effect of neoadjuvant PD-L1 on tumor-specific CD8+ T cells was investigated by adoptive transfer CD45.1+ OT-Ⅰ cells. The distribution and phenotype of CD45+ CD8+T cells in various tissues were determined by flow cytometry at the time of surgery (effector phase) and 30 d after surgery (memory phase). Results The tumor mass was reduced significantly after receiving neoadjuvant anti-PD-L1 therapy (P < 0.05). After tumor re-challenge, tumor growth was significantly slowed in the mice treated with neoadjuvant PD-L antibody, whereas TDLN resection accelerated the tumor growth (P < 0.05). However, long-term survival of tumor re-challenge showed that all tumors were eventually subsided, whether or not the mice treated with neoadjuvant PD-L antibody. The results of adoptive reinjection indicated that the number of CD45.1+ CD8+ T cells being stored in TDLN and no-draining lymph nodes (NLN) was the highest (P < 0.05). Tcm (T central memory) cells and Trm (tissue-resident memory) cells were mainly distributed in TDLN and NLN in memory phase (P < 0.05). The distribution and memory phenotype of CD45.1+ CD8+ T cells in TDLN and NLN had no obvous changes after neoadjuvant anti-PD-L1 therapy. Conclusion TDLN is the primary site for the storage of memory CD8+ T cells, but under the condition of neoadjuvant PD-L1 antibody treatment, TDLN resection does not affect their long-term anti-tumor immunity.

Mycobacterium tuberculosis( Mtb) is a pathogen of tuberculosis, and 1-deoxy-ID-xylulose- 5-phosphate reductoisomerase (DXR) is a key rate-limiting enzyme in the metabolism of Mtb, so it is thought to be a potential antibacterial target. This paper collects 35 fosmidomycin derivatives with in vitro inhibitory activity against Mycobacterium tuberculosis1-deoxy-D-xylulose-5-phosphate reductoisomerase (mtDXR), conducts a three dimensional quantitative structure-activity relationship between them by using comparative molecular field analysis ( CoMFA ) and comparative molecular similarity indices analysis (CoMSIA), and establishes corresponding models. The results show that, for CoMFA model, the best principal component value n is 7, the cross validation coefficient q² is 0.601, and the correlation coefficient r² is 0.979. For CoMSIA model, the best principalcomponent value n is 8, the cross validation coefficient q² is 0.609, and the correlation coefficient r² is 0.983. The data show that both CoMFA and CoMSIA models have good predictability. Meanwhile, the molecular docking method is introduced to further investigate the non-bonding interaction between these small molecule inhibitors of fosmidomycin and amino acid residues on target active sites. Combined with contour maps of 3D-QSAR, the modification areas of molecular structure of these compounds are determined which can be processed and optimized. On the basis of these work, this paper designs 14 new fosmidomycin derivatives, predicts their activity, and obtains a new compound 27m with higher predictive activity. The conclusions derived from this paper provide a theoretical basis and important reference for the further development of new mtDXR inhibitors. [ABSTRACT FROM AUTHOR]

Prokaryotic expression vector of mouse HPV16E6 gene was constructed. A pair of primers were designed according to the digestion sites in plasmid pGEX-KG and the HPV16E6 gene sequence published by GenBank. The DNA fragment of 321bp was amplified by PCR from the HPV recombinant plasmid with HPV16E6 gene, then cloned into pGEX-KG and transformed into the host E. coli strain JM109. The fragment was conformed to the original sequence, which indicated that fusion expression vector pGEX-KG-HPV16E6 was constructed. The pGEX-KG-HPV16E6 plasmid was taken and transformed into BL21(DE3) for expression. Induced by IPTG at 37 degrees C, the expression product of HPV16E6 gene was identified by SDS-PAGE and Western blot. HPV16E6 fusion protein had been expressed successfully in the form of inclusion bodies, the molecular weight of fusion protein being 38 kD. Meanwhile, the optimum condition of HPV16E6 fusion protein expression was induced with 1.0 mmol/L IPTG for 4h. The fusion protein reacted specifically with the antibodies against HPV16E6. HPV16E6 gene was successfully expressed in E. coli, which could be used as a basis for preparing HPV16E6 vaccine in human.

Anoxygenic phototrophic bacteria (APB) are good model organisms used to study the origin and evolution of life, photosynthesis and nitrogen fixation mechanism. With increasingly available genetic information and establishment of sequencing techniques for nucleic acid, more attention has been paid to exploration of APB resources from various habitats especially extremely environment. The pace of new species description has been increasing in recent years, and some new taxonomic taxa are also proposed, therefore, it is necessary to redefine APB and provide the newest taxonomic system of APB. We reviewed the problems and prospect about taxonomy of anoxygenic phototrophic bacteria. The definition, situation of the taxonomy, characteristics for APB identification are noted and commented from the discovery of APB up to now.