Study on intralymphatic-targeted hyaluronic acid-modified nanoliposome: influence of formulation factors on the lymphatic targeting.

In this study, hyaluronic acid-modified docetaxel-loaded liposomes were prepared to evaluate the lymphatic targeting after subcutaneous administration, and formulation factors affecting the lymphatic targeting were examined, including free hyaluronic acid, molecular weight, hyaluronic acid-density and particle diameter. The high molecular weight hyaluronic acid-modified docetaxel-loaded liposomes (HA-LPs) and low molecular weight hyaluronic acid-modified docetaxel-loaded liposomes (LMWHA-LPs) were prepared via electrostatic attraction. The physicochemical properties and in vitro drug release were evaluated. The lymphatic drainage and the lymph node uptake were investigated by pharmacokinetics and distribution recovery of docetaxel in lymph nodes, injection site and plasma. The lymphatic targeting ability of optimized Cy7-loaded LMWHA-LPs (LMWHA-LPs/Cy7) was evaluated by near-infrared fluorescence imaging technique. The result showed that HA-LPs and LMWHA-LPs with suitable and stable physicochemical properties could be used for in vivo lymphatic targeting studies. Hyaluronic acid-modified liposome significantly increased the docetaxel recovery in lymph nodes, and displayed higher AUC(0-24h) and longer retention time compared to unmodified liposomes in vivo. In contrast, the presence of free hyaluronic acid hindered the lymphatic drainage and increased the plasma-drug concentration. Importantly, LMWHA-modification improved lymphatic drainage and lymph node uptake of liposomes compared with HA-modification. And Lymph node uptake of LMWHA-LPs depended mainly on LMWHA-density instead of particle size. The results of in vivo imaging showed that LMWHA-LPs/Cy7 significantly located in the lymphatic system. And both DTX-loaded and Cy7-loaded LMWHA-LPs had similar and stable lymphatic target level. Our investigation showed that LMWHA-LPs were a highly promising lymphatic targeting carrier for chemotherapy drugs and diagnostic fluorescence agents.

Sequence analysis of secretory antigen P53 and immunological identification of the recombinant product of Trichinella spiralis / 中华传染病杂志

Objective To analyze the immunological characteristics of Trichinella spiralis secretory antigen P53 and to evaluate its value in diagnosis of trichinellosis. Methods An open read frame of secretory antigen P53 was cloned from Trichinella spiralis by reverse transcriptasepolymerase chain reaction (RT-PCR) and then sequenced. Bioinformatics analysis was performed to search for its homologues in other helminths and predict its potential linear B cell epitopes and T cell epitopes. The sequence coding mature peptide was inserted into prokaryotic expression vector pET28a(+) and the purified recombinant product was identified by Western blot using serum samples of patients infected with Trichinella spiralis or other helminth. Results Bioinformaties analysis results showed that there was no P53 homologue in other helminths, which indicated that there were many linear B cell epitopes and T cell epitopes in TsP53. The recombinant P53 antigen only reacted with the serum samples of patients infected with Trichinella spiralis without any cross-reaction with the serum of patients infected with other helminths. Conclusion P53 has strong immunogenicity and immunoreactivity, which may be a promising candidate for developing Trichinella spiralis specific diagnostic method.