Vaccine potential of the <i>Y. pestis</i> Kim53Δ<i>nlpD</i> strain against bubonic plague.

aMice were immunized subcutaneously with 105 cfu of the indicated Y. pestis strains. bAnti-F1 and anti-V titers were determined by ELISA. cFifty days post immunization, mice were challenged subcutaneously with 105 LD50 of the virulent Y. pestis Kimberley53 strain (1 LD50 = 1–3 cfu).a. 以10^5菌落形成单位（cfu）的指定鼠疫耶尔森菌（Y. pestis）菌株对小鼠进行皮下免疫。 b. 通过酶联免疫吸附试验（ELISA）检测抗F1抗体与抗V抗体的效价。 c. 免疫后第50天，以10^5半数致死量（LD50）的强毒型鼠疫耶尔森菌Kimberley53菌株对小鼠进行皮下攻毒（1 LD50=1~3 cfu）。