Bisphosphonate effect on murine whole draining lymph nodes before and 8 hours after VSV infection. Mus musculus

Bisphosphonates are a class of drugs that are widely used to inhibit loss of bone mass in patients. We show that the administration of clinically relevant doses of bisphosphonates in mice increases antibody responses to live and inactive viruses, proteins, haptens and existing commercial vaccine formulations. Bisphosphonates exert this adjuvant-like activity in the absence of CD4+ and γδ T cells, neutrophils or dendritic cells and their effect does not rely on local macrophage depletion nor does it depend upon Toll-like receptor signaling or the inflammasome. Rather, bisphosphonates target directly B cells and enhance B cell expansion and antibody production upon antigen encounter. These data establish bisphosphonates as a novel class of adjuvants that boost humoral immune responses. Of note, gene-expression profile analysis shows that bisphosphonate treatment up-regulates a number of B cell-specific transcripts and gene sets associated with B cell function, suggesting that bisphosphonates might directly target B cells. Overall design: C57Bl/6 mice received intrafoodpad injections of Clodronate (CLD, 2mg) or vehicle control (PBS) 3 and 1 day prior to infection with VSV serotype Indiana in the same footpad. Popliteal lymph nodes were harvested immediately before or 8 hours after the infection. Total RNA was extracted and prepared for hybridization on Affymetrix microarrays.

双膦酸盐（Bisphosphonates）是一类被广泛用于抑制患者骨量流失的药物。本研究证实，在小鼠体内给予临床相关剂量的双膦酸盐，可增强其对活病毒、灭活病毒、蛋白质、半抗原以及现有商用疫苗制剂的抗体应答。双膦酸盐的这类佐剂样活性不依赖CD4+ T细胞、γδ T细胞、中性粒细胞或树突状细胞；其作用既不依赖局部巨噬细胞耗竭，也不依赖Toll样受体信号通路或炎性小体（inflammasome）。相反，双膦酸盐可直接靶向B细胞，在抗原接触后增强B细胞增殖与抗体产生。上述数据确立双膦酸盐为一类可增强体液免疫应答的新型佐剂。值得注意的是，基因表达谱分析显示，双膦酸盐处理可上调多种B细胞特异性转录本以及与B细胞功能相关的基因集，提示双膦酸盐或可直接靶向B细胞。实验设计：C57Bl/6小鼠在同一足垫接种水疱性口炎病毒（Vesicular Stomatitis Virus, VSV）印第安纳血清型的3天和1天前，分别经足垫内注射氯膦酸盐（Clodronate，CLD，2mg）或溶剂对照磷酸盐缓冲液（Phosphate Buffered Saline, PBS）。分别于感染前即刻及感染后8小时采集腘窝淋巴结。提取总RNA并制备样本，用于Affymetrix微阵列杂交检测。