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O estudo de conidiobolomicose ovina tem sido realizado nos seus aspectos clínicos, epidemiológicos, patológicos e moleculares. Informações, entretanto, sobre a resposta imune do hospedeiro na infecção por Conidiobolus lampraugessão inexistentes. Este estudo teve por objetivo a identificação de proteínas imunorreativas que possam desempenhar papel importante na resposta imune de ovinos naturalmente infectados por C. lamprauges. Para a caracterização protéica e imunológica foi utilizada a cepa de C. lamprauges(FIOCRUZ-INCQS 40316) isolada de ovino com sinais clínicos de conidiobolomicose no Estado do MT e cinco amostras de soro de ovinos infectados naturalmente pelo fungo. A presença de anticorpos IgG foi observada em todos os animais doentes com títulos reagentes em diluições de até 1:1.600. Na técnica do immunoblot, o perfil antigênico frente aos soros ovinos com a doença apresentou doze bandas reativas, com massas moleculares variando de 35 a 198 kDa. Dentre estas, a proteína de 198 kDa foi reativa em 3 soros de ovinos e a de 53 kDa apresentou a maior intensidade comparativamente com outras bandas, sendo provavelmente imunodominante. Amostras de soro de animais sadios não apresentaram reatividade demostrando a especificidade da técnica. A presença de proteínas antigênicas de C. lamprauges e IgG específicos em soros de ovinos observados no presente trabalho poderá auxiliar no desenvolvimento de métodos de diagnóstico precoces e na utilização de proteínas candidatas a vacinas para o controle e prevenção da infecção em animais e humanos.

The humoral immune response plays an important role in the clearance of Giardia lamblia. However, our knowledge about the specific antigens of G. lamblia that induce a protective immune response is limited. The purpose of this study was to identify and characterise the immunogenic proteins of G. lamblia in a mouse model. We generated monoclonal antibodies (moAbs) specific to G. lamblia (1B10, 2C9.D11, 3C10.E5, 3D10, 5G8.B5, 5F4, 4C7, 3C5 and 3C6) by fusing splenocytes derived from infected mice. Most of these moAbs recognised a band of ± 71 kDa (5G8 protein) and this protein was also recognised by serum from the infected mice. We found that the moAbs recognised conformational epitopes of the 5G8 protein and that this antigen is expressed on the cell surface and inside trophozoites. Additionally, antibodies specific to the 5G8 protein induced strong agglutination (> 70-90%) of trophozoites. We have thus identified a highly immunogenic antigen of G. lamblia that is recognised by the immune system of infected mice. In summary, this study describes the identification and partial characterisation of an immunogenic protein of G. lamblia. Additionally, we generated a panel of moAbs specific for this protein that will be useful for the biochemical and immunological characterisation of this immunologically interesting Giardia molecule.

Vibrio vulnificus (V. vulnificus)は，世界中の沿岸海水中に広く生息し，本菌に汚染された魚介類の生食や創傷からの菌の侵入により感染する．発熱，四肢の壊死性筋膜炎等の症状を呈し，短期間で死に至る極めて予後不良の疾患である．V. vulnificus感染症患者の多くは基礎疾患に肝硬変や肝癌等の肝機能障害を有する．日和見感染症である本症において有効なワクチンの開発が重要であり，免疫原性の高い抗原の同定が必要である．今回我々は，V. vulnificusのヒト血清における免疫原性の高い抗原を確認することを目的とし，V. vulnificus感染症患者10名の血清を用いた菌溶解液(V. vulnificus7株，V. parahaemolyticus1株)のimmunoblottingを施行し，感染による抗体産生を分析した．発症時からすでに見られる62-kDaのbandは，患者のみならずV. vulnificus感染症未発症の慢性肝機能障害者及び肝機能正常者のいずれの血清を用いたimmunoblottingにおいても共通して認められた．また，Escherichia.coliやKlebsiella pneumoniaeを用いたimmunoblottingにおいても同様の反応を認め，交差反応を起こしている可能性も考えられた．今回の実験から，V. vulnificusの62-kDaの蛋白がヒトにおける免疫原性の高い抗原の一つであることが予想された．, Vibrio vulnificus infection can cause necrotizing fasciitis and sepsis and can develop within a few days despite intensive care. The mortality rate is up to 60% in vulnerable people. Most patients infected with this microbe have chronic liver disease, especially liver cirrhosis or cancer, as an underlying disease. V. vulnificus infection is opportunistic, and there is an urgent need to develop an anti-V. vulnificus vaccine. Thus, it is important to identify immunogenic antigens. We collected human sera from three subject groups : patients with V. vulnificus infection, patients with chronic liver disease but without V. vulnificus infection, and healthy volunteers with normal liver function. Immunoblots of cytosolic and membrane proteins of seven strains of V. vulnificus and one of V. parahaemolyticus were performed with sera from these groups. Although we could not demonstrate differences in antibody response between the groups, all sera showed a strong antibody response to a 62-kDa protein that was common to all strains examined. Immunoblots of Escherichia coli and Klebsiella pneumoniae also showed strong antibody response to this 62-kDa protein, and the possibility of cross-reaction cannot be denied. We identified this 62-kDa protein as an immunogenic antigen of V. vulnificus for humans.

近交系WHT/Htマウスの自然発生扁平上皮癌細胞よりブタノールにて抽出した粗抽出液の性状を解析するため,これをDEAE-Sephacel column chromatographtyにて部分精製し,リンパ球腫瘍抗原混合培養反応(Mixed lymphocyte-tumor antigen culture reaction)により検索した.1)粗抽出液をDEAE-Sephacel column chromatographyにて部分精製すると,NaClの濃度によりP1,P2,P3,P4の4画分に分離溶出された.2)各画分についてリンパ球-腫瘍抗原混合培養反応にて検索した結果,P3で蛋白量が10-1 μgの時〔3H〕-thymidineの取り込みが有意に高値を示し,その等電点は弱酸性であった.3) P3画分をSDS-ポリアクリルアミドゲル電気泳動したところ,約18Kのバンドが最も濃染した.4) P1,P4にて〔3H〕-Thymidineの取り込みが抑制されたことよりP3にはimmunogenic antigen P1,P4にはsuppressogenic antigenの存在が示唆された