Development of a sub-unit vaccine to protect swine against the infections caused by Streptococcus suis

猪链球菌是引起断奶仔猪细菌性疾病的重要原因之一。受影响的动物患有脑膜炎(受影响的大脑)、心内膜炎(受影响的心脏)、关节炎(受影响的关节)和败血症(全身感染)。猪链球菌有35个血清型(相同的细菌但不同的抗原)。其中一些血清型(如2型)也可影响人类(从猪传播)，导致严重疾病。通常，兽医使用抗生素来治疗甚至保护动物。然而，抗生素的大量使用导致了对抗生素耐药性的增加，目前已有许多猪链球菌产生耐药性。不幸的是，市场上没有有效的疫苗来预防这种感染。我们已经确定了一种名为“SAO”的蛋白质，它可以保护猪免受猪链球菌2型细菌株的侵袭。目前尚不清楚它是否对其他菌株和其他导致猪疾病的血清型具有保护作用。还应改进SAO蛋白的生产，以获得可接受的产量，以便有足够的材料在大型疫苗试验中进行测试。此外，这种蛋白质应该与一种非常好的提高或帮助动物免疫反应的药理学试剂(称为“佐剂”)混合在一起。需要找到一种可以在猪身上商业化使用的SAO蛋白的良好佐剂。

Streptococcus suis is one of the most important causes of bacterial disease in post-weaned piglets. Affected animals suffer from meningitis (affected brain), endocarditis (affected heart), arthritis (affected joints) and septicemia (general infection). There are 35 serotypes of S. suis (same bacteria but different antigens). Some of these serotypes (such as serotype 2) can also affect humans (transmission from pigs), causing serious disease. Usually, veterinarians use antibiotics to treat and even protect animals. However, the large use of antibiotic induces the increase of antibiotic-resistance and there are now many S. suis bacterial strains that are resistant. Unfortunately, there are no effective vaccines in the market to protect against this infection. We have identified a protein called "Sao" that protects pigs against a bacterial strain of S. suis serotype 2. It is not known if it protects against other strains and other serotypes that cause disease in pigs. Production of Sao protein should also be improved to obtain acceptable yields to have enough material to be tested in a large vaccine trial. In addition, this protein should be mixed with a very good pharmacological agent that increase or aid the immune response of animals (called "adjuvant"). A good adjuvant for Sao protein that is allowed to be commercially used in pigs needs to be found.