Pengembangan uji serologis metode ELISA imunoglobulin-A terhadap Early Antigen virus Epstein-Barr (EBV-EA IgA) untuk deteksi kanker nasofaring

PARAMITA, Dewi Kartikawati, Prof.dr. S. Mubarika, M.Med.Sc.,PhD

2003 | Tesis | S2 Bioteknologi

Nasopharyngeal carcinoma (NPC) is a tumor derived from epithelium surface of nasopharynx. Epidemiologically, one of the most striking characteristics of the disease is its geographical distribution. In South East China, the incidence varies from 30-80 per 100.000 per year. In Indonesia, NPC is the 3"^ among other malignancies. All histological types of NPC are related with Epstein-Barr Virus. One of NPC type that classified by WHO as undifferentiated carcinoma (type 3), is 100% related with EBV. This type is the most profound cases among other NPC types in Indonesia. Most of NPC patients in Indonesia come to the hospital at the latest stage, which cause unsatisfactory therapy. In order to overcome this problem, an affordable early diagnostic using simple and relatively cheap method is needed. In this investigation. Early Antigen (EA) of Epstein-Barr Virus, which is expressed at the beginning of tumorigenesis is used and to detect in the early stage of NPC using Enzyme-Linked Immunosorbent Assay (ELISA) method. The aim of this research was to develop serological test using ELISA IgA to the early antigen extracted from EA nuclear. EA nuclear derived from HH514-cl6 EBV infected cell line that induced by tumor promoting agent and phosphonoacetic acid (PAA) was precipitated by NaCl in different concentrations. The extract that contained EA proteins but no EBNAl and VCA proteins was produced. The concentration of this extract was measured with micro BCA protein assay kit. Checkerboard was made to determine the appropriate concentration of antigen and amount of antibody in the serum. Optimization of the ELISA was done to standardize blocking buffer, sample and conjugated diluents. One hundred and twenty one (121) NPC sera and one hundred and twenty six (126) normal sera were tested using this technique. The best result was shown in the extract of 0.3M NaCl, containing EA proteins (pl38, DNase and complex EAd p47-p54) and no EBNA-1 and VCA proteins. This extract also contained immediate early protein such as ZEBRA. The ELISA IgA test could differentiate NPC and normal sera, and showed 89.26% analytical sensitivity and 97.62% analytical specificity.

Kata Kunci : Bioteknologi,Virus EBV,EA IgA,Deteksi Kanker Nasofaring