Tissue Transglutaminase (tTG; Ec)

Diseases:
Celiac Disease
 

Celiac disease is an enteropathy that is characterized by intestinal lesions of variable severity. Tissue-type transglutaminase (tTG) is believed to be the predominant autoantigen for celiac disease, and the corresponding autoantibodies show higher sensitivity and specificity than anti-gliadin antibodies. Highly pure recombinant human tTG is now available to replace the traditionally used tTG fraction from guinea pig.

Tissue-type transglutaminase antigens from DIARECT have been specifically modified for improved handling: exchange of an active site amino acid eliminates the protein cross-linking activity of the enzyme, while maintaining the native three-dimensional structure and the enzymes secondary GTPase activity. This engineering assures reproducible properties of the antigen preparations by eliminating variable and ill-defined covalent aggregates of tTG antigen and host-cell proteins.

Two recombinant human tissue transglutaminase products are available from DIARECT, expressed in baculovirus / Sf9 insect cells and E.coli respectively. 

相關疾?。蝴熧|過敏癥麩質過敏癥又叫做乳糜瀉，是指在遺傳性的易感個體中，一種在小腸炎癥條件下導致的對攝入一定的飲食谷蛋白——麥醇溶蛋白過敏癥。該疾病的發病機制來自環境的，遺傳的和免疫的因素的相互作用的結果。對該種病人唯一的治療辦法就是終生禁止含麥醇溶蛋白食物的飲用，這樣能使腸黏液得到恢復。組織型谷氨酰胺轉移酶做為抗原可檢測出自身抗體，促使發病機制得到更好的理解并且促進了重要的血清學測試的發展。麩質過敏癥是一種以不同程度腸損傷為特征的腸病。組織型谷氨酰胺轉移酶（tTG）被認為是麩質過敏癥的主要抗原，其相應的抗體比其他抗麥膠蛋白抗體具有更高的靈敏性和特異性。高純度的重組人tTG現可用來替換傳統的荷蘭豬tTG片段。DIARECT生產的tTG抗原特別改進了工藝：替換掉了一個氨基酸活性位點以消除酶的交叉反應活性，同時保持了蛋白的天然三維結構和酶的次級GTP酶活性。該工程通過消除可變的不清楚的tTG抗原和宿主蛋白的共價聚合，保證了抗原的可再制性。

DIARECT生產的兩種tTG抗原分別在昆蟲細胞和大腸桿菌表達系統中表達。