Nghiên cứu tạo kháng nguyên tái tổ hợp Staphylococcal Enterotoxin B (SEB) từ đoạn gen đột biến điểm SEB dài 534 nucleotide

Tgp chi Cong ngh? Sinh hgc 12(1): 173-180, 2014

NGHIEN CUlJ TAG iCHANG NGUYEN TAI TO HOP STAPHYLOCOCCAL

ENTEROTOXIN B (SEB) TlT DOAN GEN DO T BIEN DIE M SE B DAI 534 NUCLEOTIDE

TVan Minh Tri', Nguyin Thj Hoai Thu^ Biii Van Ngoc^ Le Trong Van', Pham Thdy Linh^ Nghiem

Nggc Minh^

' Vi^n Ky thudt Hoa sinh vd Tdi li^u nghiep vu. Bg Cong an

^Vi4n Cong nghe sinh hgc, Vien Hdn Idm Khoa hgc vd Cong nghe Viet Nam

Ngaynhanbai: 08.02.2014

Ngaynhandang: 19.3.2014

TOM TAT

Cic doc to nipt Staphylococcal enterotoxins (SEs) la nguyen nhan chinh gay ngo dpc thuc pham tren toan

the gidi. Trong d6, npi dpc to Staphylococcal enterotoxin B (SEB) la nguyen nhan chii yeu va duoc liet ke vao

danh myc vii khi sinh hoc sir dung trong chien traith va khiing bo sinh hpc, Vi vay, viec phat hien nhanh, chinh

xic dpc to rupt SEB la rat quan trpng, Trong nghien ciiu nay, chiing toi da tiln hanh bilu hien gen SEB mang

bon dpi bien diem tai cac vi tri bp ba ma hoa lan lupt la 12, 32, 105 va 121, co kich thuoc 534 nucleotide vk

tinh sach de t?o ra nguon khang nguyen tai t6 hgp SEB khong doc hoac co dpc tinh thSp dl gay dap iing rmln

dich, tao khing the don dong, da dong bat cap dac hieu vai SEB tir nhien tii do co thl tao dupc que thiir phat

hi|n nhanh dpc to nay Kit qua cho thSy trong dieu kien nuoi ciy co chit cam iing, dong E. coli BL21 (DE3)

mang vector pET22b+/mtSEB534 da sinh tfing hpp protein ngoai lai manh co kich thuoc khoang 22 kDa tuong

ling v6i protein mtSEB534, Viec thay ddi cac dieu kien bieu hien nhu n6ng do chit cam iing IPTG, nhiet dp da

ISm tang hkm lupng mtSEB534 len 16,9 mg/lOO ml moi truang nuoi cay dua U-en viec phan tich biing phiin

mem Quantity one 4,6.7 (Bio-Rad, My). SEB534 tai to hop da dupc tinh chl thanh cong bing cpt sic ky ii luc

HisTrapNiken v6i hieu suat dat 10 mg SEB534 Hnh sach trong 100 ml moi truong vai do tinh sach Uen 95%.

Tit' khda: Bieu hi^n protein tdi to hgp, Escherichia coh. mtSEB534, protein the viii. Quantity one

Ty cau vang Staphylococcus aureus la mpt trong

nhOng nguyen nhan chinh gay ngp dpc thuc pham

tren loan cau do chiing tiet ra cac dpc to rupt

staphylococcal enterotoxins (SEs). Trong do, doc to

Staphylococcal enterotoxin B (SEB) la tac nhan chii

yeu dupc li?I v^o danh sach cac loai vu khi smh hoc

(Agrawal et al, 2012). SEB co dpc tinh manh vai

lieu gay chk 50% (LD50) la 0,02 (ig^g (Gleason,

2013). SEB tk ban vdi nhiet (Jones, Khan, 1986) va

dupc coi la mpl "sieu khang nguyen" ciia vi khuan vi

n6 c6 the 1^0 thanh mpt "cau noi" giiia MHC lop II

cua cic te bao trinh dien khang nguyen voi vimg Vp

ciia c^c thu the t^ bao T nhu CD 4, CD 8; tir do, kich

thich ho^il hoa cac te bao T bieu hien cac doan gen

Vp mi khong can Ihiet phai co qua Irinh thuc bao va

Irinh di?n thong thuang. Sieu khang nguyen bam

tryc tiep vao phiic hpp MHC lap II tai vi Iri khac vai

vj Iri bam thong thuang ciia khang nguyen. Ttr do

u6c tinh khoang 1/5 so te bao T uong co the bi kich

thich s4n xuit cytokin nhu cytokine, inlerleukin 2

(IL-2), cic yeu t6 hogi tir khoi u p (TNF-P). va cac

interferon mpt each 6 at gay nen hien Urong soc dpc

cho CO the Vi vay, khi bi nhiem doc SEB qua duimg

an uong, benh nhan co cac trieu chirng nhu chan an,

buon non, non, va tieu chay. Cac trieu chirng nay

xuat hien la do cac cytokine trong cac te bao T ciia

bieu mo ruot duac smh ra 6 at (Gleason, 2013). Vi

vay, viec phat hien cac thuc pham nhiem SEB la can

thiel de giam thieu chi phi y te do nhiem doc Ihuc

pham cung nhu de bao ve siic khoe cpng dong.

Hien nay co nhieu phuong phap co the phat hien

SEB nhu phucmg phap PCR phat hien gen ma hoa

SEB CO mat trong Ihuc pham hoac phuang phap

chan doan mien dichdua tren phan iing dac hieu giiia

khang nguyen-khang the nhu phuang phap ELISA,

Western blot,.,, Tuy nhien, dang sac ki mien dich

(Immunochoromatography test hay lateral flow test

strip) cho ket qua Irong thoi gian ngan khoang tir 5

den 10 phiit, dp nhay co (ng/ml) va dp dac hieu cao

luon duoc uu tien lua chpn hang dau de Hen hanh

kiem tra sang loc giiip phat hien nhanh cac tie nhan

sinh hpc nguy hiem nhu cac loai dpc to, vi khuin,

virus . Hien nay, tren thj trudng co ban sSn mpt so

kit Ihucmg mai de phal hien true tiep cac SEs nhu'

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