Activates B lymphocytes and enhanced immune response: A promising adjuvant based on PLGA nanoparticle to improve the sensitivity of ZEN monoclonal antibody.

In preparing monoclonal antibodies by hybridoma cell technology, the quality of B lymphocytes used for cell fusion directly affects the sensitivity of monoclonal antibodies. To obtain B-lymphocytes producing high-quality specific antibodies for cell fusion during the immunization phase of the antigen, we prepared a TH2-Cell stimulatory delivery system as a novel adjuvant. Astragalus polysaccharide has a good ability to enhance antigenic immune response, and it was encapsulated in biocompatible materials PLGA as an immunostimulatory factor to form the delivery system (APS-PLGA). The preparation conditions of APSP were optimized using RSM to attain the highest utilization of APS. Immunization against ZEN-BSA antigen using APSP as an adjuvant to obtain B lymphocytes producing ZEN-specific antibodies for cell fusion. As results present, APSP could induce a stronger TH2 immune response through differentiating CD4 T cells and promoting IL-4 and IL-6 cytokines. Moreover, it could slow down the release efficiency of ZEN-BSA and enhance the targeting of ZEN-BSA to lymph nodes in vivo experiments. Ultimately, the sensitivity of mouse serum ZEN-specific antibodies was enhanced upon completion of immunization, indicating a significant upregulation of high-quality B lymphocyte expression. In the preparation of monoclonal antibodies, the proportion of positive wells for the first screening was 60%, and the inhibition rates of the antibodies were all similar (>50%). Then we obtained the ZEN monoclonal antibody with IC50 of 0.049 ng/mL, which was more sensitive than most antibodies prepared under conventional adjuvants. Finally, a TRFIAS strip assay was preliminarily established with a LOD value of 0.246 ng/mL.

Analysis of medical malpractice litigation following vertebral augmentation therapy in China from 2008 to 2018.

The first case of vertebral augmentation therapy in mainland China was reported in 2000. Since then, it has been widely used in China as a minimally invasive procedure to treat vertebral compression fractures. However, the characteristics of malpractice litigation involving vertebral augmentation therapy remains unclear. This study aims to analyze the characteristics of medical malpractice litigation involving vertebral augmentation therapy in mainland China for the past 10 years. Two online legal databases were queried for court verdicts involving vertebral augmentation therapy from Jan 2009 to Dec 2018 in mainland China. Each case file was then thoroughly reviewed and data pertaining to defendants, plaintiffs, case outcomes, allegations, and verdicts were abstracted, and descriptive analyses were performed. Level of evidence: LEVEL III. A total of 96 cases were enrolled for final analysis. The number of claims increased by five times during the past 10 years. More than two thirds (67.7%, n = 65) of the cases underwent percutaneous vertebroplasty, and 22.9% (n = 22) underwent percutaneous kyphoplasty, the rest (9.4%, n = 9) remained undefined. Paralysis was alleged in 35.4% of cases (n = 34), followed by significant physical injury (34.4%, n = 33). Cement leakage to spinal canal (44.8%, n = 43) is the most commonly cited reason for litigation, followed by incomplete informed consent (42.7%, n = 41), accidental dural puncture (20.8%, n = 20), unsatisfactory clinical outcome (18.8%, n = 18), and misdiagnosis (12.5%, n = 12). Acute pulmonary cement embolism (4.2%, n = 4), wrong-level vertebrae procedure (3.1%, n = 3) and postoperative infection (2.1%, n = 2) were less common causes for concern. Doctors successfully defended themselves only in 8 (8.3%) cases, which resulted in no indemnity payment. The rest 88 (91.7%) cases were closed with a mean verdict payout of 361,580 Yuan (51,654 US dollars). There is a quickly rising trend in the number of medical malpractice litigation involving vertebral augmentation therapy in China. Identifying the most common reasons for litigation and summarizing their characteristics may help decrease litigation rate and improve the patient experience.