Vega Laura E Orozco, Rodríguez Sergio D, Alarcón Germinal J Cantó, Flores Rafael López, Ocampo Rafael Jiménez, Ortiz Miguel Angel García, de la Torre Jesús Francisco Preciado, Ramírez Edmundo E Rojas
Campo Experimental Pichucalco, INIFAP, Km 8, Carr. Pichucalco-Teapa, Chiapas, Mexico.
Vaccine. 2007 Jan 5;25(3):519-25. doi: 10.1016/j.vaccine.2006.07.049. Epub 2006 Aug 7.
Twenty four Hereford heifers free of anaplasmosis were allotted into three groups of eight animals each and inoculated three times with adjuvant in Puck saline as control or 50 microg and 100 microg of total protein of Anaplasma marginale initial bodies from three Mexican strains which share the same variable region of msp1alpha and msp4. Inoculation with the adjuvant or the immunogen at either of the two protein doses did not induce any undesirable changes attributable to inoculation in vaccinates or controls. On day 78 post vaccination animals were released in a ranch where bovine Anaplasmosis is endemic. The A. marginale strain prevalent in this ranch shares some of the msp1alpha tandem repeats with and the strains used in the vaccine. After release, all animals became infested with Boophilus microplus ticks and flies. During the challenge period, between days 279 and 300, loss of PCV due to clinical anaplasmosis in control animals was statistically higher from vaccinated animals. Likewise, controls mean peak rickettsemia was also significantly higher (p< or =0.01) than vaccinates' rickettsemias. The antibody responses of all vaccinates after the third vaccination reached OD values above 2.0 on day 49 and were different from controls (p<0.01). IgG(2) responses from both groups of vaccinates were different from controls (p<0.01). Vaccinates which required treatment, also showed the lowest IgG(2) and substantial IgG(1) responses. After contact with the rickettsia, controls developed clinical disease and 7 out of 8 required treatment, while vaccinates in general showed no substantial changes in hematocrit or rickettsemia and only one animal in each group required treatment. Our present results show that vaccination with either 50 microg or 100 microg of protein from purified IB derived from three strains induced protection to resist the challenge with the a field strain that shares some of the tandem repeats of MSP1a.
将24头无无形体病的赫里福德小母牛分成三组，每组8头，分别用帕克氏盐水中的佐剂作为对照进行三次接种，或用来自三个墨西哥菌株的50微克和100微克边缘无形体初始体总蛋白进行接种，这三个菌株共享msp1α和msp4的相同可变区。用佐剂或两种蛋白剂量中的任何一种免疫原接种，均未在接种疫苗的动物或对照中引起任何归因于接种的不良变化。在接种疫苗后第78天，将动物放归到牛无形体病流行的牧场。该牧场中流行的边缘无形体菌株与疫苗中使用的菌株共享一些msp1α串联重复序列。放归后，所有动物都感染了微小牛蜱和苍蝇。在攻击期，即第279天至300天之间，对照动物因临床无形体病导致的红细胞压积损失在统计学上高于接种疫苗的动物。同样，对照动物的平均立克次体血症峰值也显著高于（p≤0.01）接种疫苗动物的立克次体血症。所有接种疫苗的动物在第三次接种后的抗体反应在第49天达到OD值高于2.0，且与对照不同（p<0.01）。两组接种疫苗动物的IgG(₂)反应均与对照不同（p<0.01）。需要治疗的接种疫苗动物也表现出最低的IgG(₂)和大量的IgG(₁)反应。与立克次体接触后，对照动物出现临床疾病，8头中有7头需要治疗，而接种疫苗的动物总体上红细胞压积或立克次体血症没有明显变化，每组只有1头动物需要治疗。我们目前的结果表明，用来自三个菌株的纯化初始体的50微克或100微克蛋白进行接种可诱导保护，以抵抗与共享MSP1a一些串联重复序列的田间菌株的攻击。
