I. Tng qut v INTERFERON 1.

1 Gii thiu v interferon Interferon (IFN) c Isaacs v Linderman pht hin nm 1957, y l mt cht do t bo bch cu v lympho bo sinh ra, c bn cht protein, c ng dng lm thuc phng v iu tr cc bnh nhim trng do virut v ung th. C 3 loi IFN l a, b v g (gamma). Interferon (IFN) l cc protein c to ra bi h thng min dch p ng vi vic c th nhim virus, cc t bo ngoi lai, khng nguyn v.v.. Chng ng vai tr quan trng trong c ch bo v, khng ca c th. Interferon l mt nhm cc protein t nhin c sn xut bi cc t bo ca h thng min dch hu ht cc ng vt nhm chng li cc tc nhn ngoi lai nh vi rt, vi khun, k sinh trng v t bo ung th. Interferon thuc mt lp ln ca glycoprotein c bit n di ci tn cytokine (cht hot ho t bo). Interferon ng vai tr quan trng trong ca ng min dch u tin ca c th. N l mt phn ca h thng min dch khng c hiu (non-specific immune system) v c kch hot bi giai on u ca qu trnh cm nhim trc khi h min dch c hiu (specific immune system) c thi gian p ng. Interferon (IFN s) l protein sinh ra bi t bo lympho p ng vi s hin din ca tc nhn gy bnh chng hn nh vi rt , vi khun , k sinh trng , hoc khi u t bo. Chng cho php s giao tip gia cc t bo kch hot h thng phng th bo v ca h min dch tiu dit cc mm bnh hoc c khi u. IFNs thuc v lp ln ca glycoprotein gi l cytokine IFNs cn c cc chc nng khc: kch hot t bo min dch, chng hn nh cc t bo git t nhin v i thc bo , chng lm tng s cng nhn ca nhim trng hoc cc t bo khi u ln iu tit hot ng khng nguyn cho t bo

lympho T , v chng lm tng kh nng ca cc t bo ch khng b ly nhim chng li s nhim trng mi t virus (chng ly lan). Mt s triu chng ch yu chng hn nh au c bp v st, c lin quan n vic sn xut cc IFNs trong nhim trng. Khong mi IFNs khc nhau c xc nh v tm thy trong ng vt c v, by trong s ny c p dng cho con ngi Chng thng c phn chia gia ba loi IFN: loi I IFN, Type II IFN, v loi III IFN. IFNs 1.2 Cc loi interferon C 3 loi chnh

Loi I : Tt c cc loi I IFNs gn vo th th t bo phc tp mt b mt c bit c gi l IFN- th ( IFNAR ) m bao gm IFNAR1 v IFNAR2 dy chuyn. .Cc interferon loi I tn ti trong con ngi l IFN-, IFN- v IFN-.

Loi II : lin kt vi IFNGR.interferon loi II tn ti trong ngi l IFN- . Loi III : Tn hiu thng qua mt phc tp th bao gm IL10R2 (cn gi l CRF2-4) v IFNLR1 (cn gi l CRF2-12), interferon loi III t ph bin hn loi I v loi II. Chng thng c chung cc tc dng nh:khng vi rt, khng khi u, hot

ha i thc bo v t bo lympho NK (Natural Killer), tng cng s biu hin ca cc phn t MHC (MHC Major histocompatibility complex- h khng nguyn c t chc phc tp) lp I v II. Interferon alpha v beta c sn sinh bi nhiu loi t bo bao gm t bo T, B, i thc bo, nguyn bo x, t bo mng trong, nguyn bo xng v cc

loi khc. Chng u c c tnh khng vi rt v c tnh khng ung th. Chng kch thch c i thc bo v t bo NK. Interferon gamma c lin quan n s iu ha min dch v phn ng vim. Ngoi 3 loi Interferon thng dng trn cn c Interferon omega- c cc t bo bch cu sn sinh ra ngay ti ni nhim trng v ti khi u.Cc Interferon ny kch hot 20-30 protein v nhiu chc nng ca chng vn cha c hiu bit y . Tuy nhin, c 3 protein ng vai tr quan trng trong vic kch hot trng thi khng vi rt c nghin cu rng ri. S xut hin ca 1 trong cc protein ny dn n s hot ho th hai ca chng (mt ribonuclease) c th ph hu mRNA (RNA thng tin) v s xut hin ca protein th 3 (mt protein kinase) dn n s c ch bc u tin ca qu trnh tng hp protein. iu ny kch hot qu trnh tng hp protein ca vi rt nhng cng lm c ch tng hp protein ca t bo ch. V vy, cc protein ny ch c to ra v hot ho khi cn. 1.3 Chc nng Interferon kch hot s tng hp dng khng hot ng ca cc protein trong t bo ch. Double- stranded ARN l nhn t hot ho cc protein ny. N trc tip hot ho 25 oligo A synthase v protein kinase R v hot ho gin tip ribonuclease L. S hot ho cc protein ny i khi dn n s cht ca t bo nhng t nht qu trnh cm nhim vi rt c ngn chn. S nng cao phn ng min dch ti Vacxin Bi Lnh vc Pht minh ALPHA Cht khng th Pht minh ny lin quan n s Nng cao Vacxin c bit cho vic p dng trong ln. Tt c cc interferon c chung mt s hiu ng, chng l cc tc nhn khng vi-rt v c th chng li cc khi u . Khi mt t bo b nhim bnh t mt cytolytic virus, cc ht virus c phng thch c th ly nhim sang cc t bo ln cn.

Tuy nhin, t bo nhim bnh c th cnh bo cho cc t bo ln cn bit s hin din ca virus bng cch gii phng interferon Cc t bo ln cn, p ng vi interferon, sn xut s lng ln ca mt enzyme c gi l protein kinase R (PKR), enzyme phosphoryl ny l mt protein c gi l EIF-2 p ng vi virus ly nhim mi; EIF-2 l mt nhn in hnh dch yu t khi u hnh thnh mt phc hp khng hot ng vi cc protein khc, gi l eIF2B , lm gim tng hp protein trong t bo. Mt enzyme t bo, RNase L -cng gy ra sau PKR kch hot, ph hy RNA trong t bo gim bt s tng hp protein ca c hai v my ch lu tr gen ca virus. c ch tng hp protein tiu dit c cc vi rt v t bo ch b nhim bnh. Ngoi ra, interferon kch thch sn xut hng trm loi protein khc - c gi chung l interferon-gen kch thch (ISGs)-m c vai tr trong vic khng virus.H cng hn ch ly lan ca virus bng cch tng p53 hot ng, m git cht virus t bo b nhim bng cch thc y s t hy dit Tc dng ca IFN trn p53 cng lin kt vi vai tr bo v chng li bnh ung th nht nh. 1.4 Cm ng ca interferon Sn xut interferon ch yu chng li cc vi khun, chng hn nh vi rt v vi khun, v cc sn phm ca chng. Lin kt cc phn t duy nht c tm thy vi khun, virus glycoprotein , virus RNA , vi khun ni c t (lipopolysaccharide), vi khun tin mao , CpG motif - by th nhn dng mu , nh mng b rng buc Toll nh th hoc cc th th t bo cht RIG-I hoc MDA5 , c th kch hot pht hnh IFNs. Ging nh receptor 3 ( TLR3 ) l quan trng i vi gy kch thch interferon p ng vi s c mt ca si i RNA virus , cc phi t cho cc th th ny l si i RNA (dsRNA) .

Sau khi dsRNA gn kt, th th ny kch hot cc yu t phin m IRF3 v NF-B , l yu t quan trng bt u tng hp protein vim nhiu.Gii phng ca IFN t cc t bo ny cng gy ra bi tc nhn gy phn bo. Cytokine khc, chng hn nh interleukin 1 , interleukin 2 , interleukin-12 , yu t hoi t khi u , kch thch t khun lc , cng c th tng cng sn xut interferon. 1.5 Virus khng interferon Nhiu vi-rt tin ha cc c ch chng li hot ng interferon. Chng ph v phn ng bng cch ngn chn tn hiu IFN cui cng vi cc trng hp xy ra sau khi gn vo th th ca cytokine, bng cch ngn chn IFN sn xut thm, v bng cch c ch cc chc nng ca protein c gy ra bi IFN. Virus c ch tn hiu IFN bao gm virus vim no Nht Bn (JEV), virus st xut huyt loi 2 (DEN-2) v h vi rt herpesvirus, chng hn nh cytomegalovirus (HCMV) v Kaposi's-lin herpesvirus sarcoma (KSHV hay HHV8) ngi, protein virus c chng minh nh hng n tn hiu IFN bao gm EBV khng nguyn nhn 1 (EBNA1) v EBV khng nguyn nhn 2 (EBNA-2) t Epstein-Barr virus , cc khng nguyn T ln ca Polyomavirus , cc protein E7 ca con ngi papillomavirus (HPV), v B18R protein ca virus vaccinia . Gim- hot ng IFN c th ngn chn tn hiu thng qua STAT1 , STAT2 , hoc IRF9 (nh vi JEV nhim trng) hoc thng qua cc ng Jak-STAT ( nh vi nhim trng-2 DEN). Mt s poxviruses m ha IFN th homologs ha tan nh cc protein B18R ca virus vaccinia lin kt vi v ngn chn IFN tng tc vi th th ca t bo ca mnh, cn tr giao tip gia mc tiu ny cytokine v cc t bo ca n. Mt s virus c th m ha protein lin kt vi si i RNA (dsRNA) ngn chn cc hot ng ca RNA-ph thuc kinase protein , y l c ch reovirus thng qua s dng sigma ca 3 (3) protein, v virus vaccinia s dng bng cch s dng gen sn

phm ca gen E3L ca n, p25.Kh nng ca interferon sn xut protein t gen kch thch interferon (ISGs) cng c th b nh hng. Sn xut protein kinase R , v d, c th b gin on trong cc t bo nhim bnh vi JEV hoc flaviviruses . Mt s loi virus thot khi cc hot ng chng virus ca interferon bi gen (v do protein) t bin. Cc virus cm H5N1, cn c gi l cm gia cm, c kh nng chng interferon khng virus v cc cytokine khc c phn b cho mt n axit amin thay i trong protein ca n khng kt cu 1 (NS1), mc d c ch chnh xc v cch thc ny trao min dch l khng r rng. 1.6 Interferon iu tr bnh Cc hiu ng min dch ca interferon c khai thc iu tr mt s bnh nh b ngoi ung th biu m t bo y , u nh trong v ngoi, mn cc sinh dc, kh trng chng ung th, ma ty, v iu tr mt s bnh t min. Interferon beta-1a v interferon beta-1b c s dng iu tr v kim sot bnh a x cng , mt chng ri lon t min . iu tr ny c hiu lc cho lm chm tin trin bnh v cc hot ng trong ti-chuyn bnh a x cng v gim thiu cc cuc tn cng trong tin bnh a x cng th cp. Interferon tr liu c s dng (kt hp vi ha v x tr) nh iu tr cho nhiu bnh ung th. iu tr ny hiu qu nht iu tr bnh c tnh huyt hc , bnh bch cu v u lympho bao gm c bnh bch cu t bo lng , bnh bch cu myeloid mn tnh , ung th hch nodular , T-da t bo ung th hch . Bnh nhn thng xuyn nhn c melanomas ti t hp IFN-2b.

C hai bnh vim gan B v vim gan C c iu tr bng IFN-, thng kt hp vi khng thuc khc. Mt s ca nhng ngi c iu tr bng interferon c p ng virus hc bn vng v c th loi b vi rt vim gan. Chng gy hi nht - virus vim gan C genotype I - ch x l khong 50% thi gian ca cc tiu chun v chm sc iu tr interferon-/ribavirin. C th Vi iu tr, sinh thit cho thy gim thit hi gan v x gan . Mt s bng chng cho thy interferon ngay lp tc sau khi nhim c th ngn nga bnh vim gan C, mc d chn on sm bnh l kh khn v cc triu chng th cht l tha tht trong bnh vim gan C sm. Kim sot bnh vim gan C do IFN c kt hp vi gim ung th biu m t bo gan . Vi liu lng thp interferon c s dng rng ri ng u v Nga nh l mt phng php ngn nga v iu tr cc bnh do virus ng h hp nh cm lnh v cm . Tuy nhin, c ch ca tc dung ca interferon khng c hiu r, ngi ta cho rng liu lng phi ln c c tc dng v virus. Mc d hu ht cc nh khoa hc phng Ty ang hoi nghi v bt k khiu ni v hiu qu ca n, pht hin gn y cho thy interferon p dng i vi nim mc c th hot ng nh mt cht b tr chng li virus cm, thc y h thng p ng min dch c th chng li virus. Mt vc-xin cm interferon l cht b tr s dng hin ang c th nghim lm sng M. II. INTERFERON ALPHA 2B 2.1 Tng quan Interferon l mt nhm cc protein t nhin c sn xut bi cc t bo ca h min dch hu ht cc ng vt nhm chng li cc tc nhn ngoi lai nh virus, vi khun, k sinh trng v t bo ung th. N ch c tng hp khi c mt cc cht sinh interferon (cn gi l interferonogen). Interferon thuc mt lp ln

ca glycoprotein c bit n di ci tn cytokine (cht hot ho t bo). Interferon ng vai tr quan trng trong ca ng min dch, n l hng ro bo v u tin ca c th chng li virus v s pht trin bt thng ca t bo. N l mt phn ca h thng min dch khng c hiu (non-specific immune system) v c kch hot bi giai on u ca qu trnh cm nhim trc khi h min dch c hiu (specific immune system) c thi gian phn ng. Cn phn bit interferon ni sinh c sinh ra trong c th v interferon ngoi sinh do nui cy t bo ngoi c th. Interferon l mt loi cytokine, c t bo sn xut ra khi t bo cm th vi virus, cht ny c c tnh bng mi con ng c th c ch s hot ng ca mARN, dn n c ch s sinh sn ca virus, nh hng n sinh trng v pht trin (s phn ha) ca cc t bo khi u v t bo bnh thng nht nh no , do vy interferon c s dng nh mt cht iu tr khng c hiu cho mi nhim trng do virus. C 3 lp Interferon chnh: alpha, beta v gamma. Chng thng c chung cc tc dng sau: khng vi rt, khng khi u, hot ha i thc bo v t bo lympho NK (Natural Killer), tng cng s biu hin ca cc phn t MHC (MHCMajor histocompatibility complex- H khng nguyn c t chc phc tp) lp I v II. Interferon alpha v beta c sn sinh bi nhiu loi t bo bao gm t bo T, B, i thc bo, nguyn bo x, t bo mng trong, nguyn bo xng v cc loi khc. Chng u c c tnh khng vi rt v c tnh khng ung th. Chng kch thch c i thc bo v t bo NK. Interferon gamma c lin quan n s iu ha min dch v phn ng vim. ngi ch c duy nht mt loi Interferon gamma. N c sn sinh bi cc t bo T hot ng v t bo NK. Interferon gamma cng c vi tc dng khng vi rt v khng ung th nhng tc dng ny rt yu. Do vy, Interferon gamma khng c s dng iu tr ung th. Ngoi ra Interferon gamma cng c gii phng bi cc t bo T helper 1 v cc t bo bch cu mi v tr nhim trng - kt qu ca phn ng vim. N cng kch thch i thc bo

git vi khun c nhn chm. Interferon gamma c gii phng bi t bo T h tr 1- cng c vai tr iu ho quan trng i vi phn ng ca t bo T helper 2. Ngoi 3 loi Interferon thng dng trn cn c Interferon omega- c cc t bo bch cu sn sinh ra ngay ti ni nhim trng v ti khi u. 2.1 Cc type Interferon Da trn cc type th th m n c truyn qua, cc interferon ngi c phn loi thnh 3 type chnh.

Interferon type I: Tt c IFN I gn vo mt phc hp th th c bit b mt t bo c bit n nh l th th IFN- (IFNAR) bao gm chui IFNAR1 v IFNAR2. Cc interferon type I hin din ngi l IFN-, IFN and IFN-.

Interferon type II: gn vo IFNGR. ngi l IFN-. Interferon type III: thng tin qua mt phc hp th th bao gm IL10R2 (cng c gi l CRF2-4) v IFNLR1 (cng c gi l CRF2-12). Cch phn loi ny t thng dng hn cch phn loi theo type I v type II, v khng ging nh hai loi trn, hin ti n khng bao gm Vit tt theo k t u y khoa.

2.2 c tnh sinh hc

Interferon l nhng protein hoc dn xut ca protein c cht t glucid, vi khi lng phn t ln (2,5.104 106 dalton). Chng bn vng trc nhiu loi enzym: ribonucleaza, dezoxyribonucleaza nhng b phn gii bi proteaza v b ph hy bi nhit . c tnh sinh hc quan trng ca interferon l c tc dng c hiu i vi virus (interferon c sinh ra do mt loi virus c th km hm s nhn ln ca nhng virus khc).

2.3 S hnh thnh interferon Interferon khng phi ch sn sinh ra trong cc t bo b nhim virus m interferon cn c to thnh khi t bo b kch thch bi mt s cht l khc nh: axit nucleic, vi khun, c t ca vi khun, rikettsia, nguyn sinh ng vt. V vy s hnh thnh interferon l do s kch thch ca ngun thng tin l hay di tc ng ca bt c ngun thng tin ngoi lai no. Trong cc t bo khng b nhim virus, cc gen cu trc chu trch nhim tng hp interferon lun trng thi khng hot ng, tc l b km hm, do t bo bnh thng khng to nn interferon. Khi virus xm nhp hoc cc cht kch thch ngoi lai khc vo t bo, chng gii ta s km hm v hot ha cc gen cu trc ny, thng tin t gen cu trc ny c sao chp thnh mRNA tng ng ca t bo v chnh mRNA ny iu khin vic tng hp interferon. Interferon sau khi sinh ra mt phn li trong t bo, cn phn ln ngm qua vch t bo ra ngoi ngm vo cc t bo khc. 2.4 C ch hot ng ca Interferon Phn ln RNA v DNA virus iu nhy cm vi interferon nhng c ch v cng tc ng thay i ty loi virus. Interferon ch c tc dng chng virus bn trong t bo, khng c tc dng chng virus bn ngoi t bo, interferon khng trc tip m gin tip tc ng ln virus. Tc dng chng virus ca interferon thc cht khng phi l ngn cn s hp ph ca virus ln vch t bo cng nh ngn cn s xm nhp ca virus vo t bo, interferon khng c tc dng gii th virus. Interferon c th tc dng theo nhiu c ch khc nhau: c ch s gn virus vo receptor b mt t bo Ngn cn s thot v bc ca virus

 c ch s tng hp mRNA c ch s m ha cc protein virus,

i vi nhiu virus, hiu lc chnh ca interferon l c ch s tng hp protein virus. Sau khi nhim virus, t bo b cm ng v sn sinh ra interferon, interferon khng c tc dng bo v t bo m m ch bo v cc t bo bn cnh, cc t bo ny virus vn hp ph ln vch t bo v xm nhp vo bn trong t bo, nhng n giai on sao chp thng tin ca virus th interferon c tc dng c ch, km hm s tng hp mRNA ca virus, mRNA ca virus khng c tng hp th s chuyn ha axit nucleic v protein ca virus cng khng tin hnh c, do khng c virus mi c gii phng ra. Nguyn nhn l khi interferon ngm vo t bo gy cm ng hot ha mt on gen ca t bo ny nhm tng hp ra mt cht gi l protein khng virus (AVP: antivaral protein), chnh protein khng virus ny l nhn t cn tr s nhn ln ca virus, c th l cn tr phin dch thng tin t mRNA. Cc Interferon ny kch hot 20-30 protein v nhiu chc nng ca chng vn cha c hiu bit y . Tuy nhin, c 3 protein ng vai tr quan trng trong vic kch hot trng thi khng virus c nghin cu rng ri. S xut hin ca 1 trong cc protein ny (25 oligo A synthase) dn n s hot ho th hai ca chng (mt ribonuclease) c th ph hu mRNA (RNA thng tin) v s xut hin ca protein th 3 (mt protein kinase) dn n s c ch bc u tin ca qu trnh tng hp protein. iu ny c ch qu trnh tng hp protein ca virus nhng cng lm c ch tng hp protein ca t bo ch. V vy, cc protein ny ch c to ra v hot ho khi cn. Interferon kch hot s tng hp dng khng hot ng ca cc protein ny trong t bo ch. Double- stranded RNA l nhn t hot ho cc protein ny. N trc tip hot ho 25 oligo A synthase v protein kinase R

v hot ho gin tip ribonuclease L. S hot ho cc protein ny i khi dn n s cht ca t bo nhng t nht qu trnh cm nhim vi rt c ngn chn. c im interferon Khng th C ch hnh thnh C ch tc ng Bn cht Ni tc dng Tnh cht tc ng Tnh c hiu loi c hiu chng mm bnh Thi gian xut hin Thi gian c hiu lc Loi hnh min dch ng dng T bo b nhim virus Chng axit nucleic Protein Bn trong t bo Trc tip ln virus C Khng c Nhanh sau vi gi Ngn, mt ngay Qua trung gian t bo Can thip trc tip vcxin vo dch T bo c thm quyn min dch Chng bn thn vi khun, virus, protein khng nguyn Protein Bn ngoi t bo Trc tip ln virus, vi khun Khng C Chm sau vi ngy Vi thng n mt nm Min dch dch th C tc dng phng bnh bng vcxin v khng huyt thanh 2.5 Phn loi v ngun gc C 3 lp Interferon chnh: alpha, beta v gamma. Chng thng c chung cc tc dng nh: Khng vi rt, khng khi u, hot ha i thc bo v t bo lympho NK (Natural Killer), tng cng s biu hin ca cc phn t MHC ( MHC_Major histocompatibility complex- H khng nguyn c t chc phc tp) lp I v II. C th ng vt sn xut hai loi interferon l interferon I v interferon II. Interferon I c hot tnh khng virus bao gm interferon- (IFN-, khi lng phn t khong t 17-26 kDa, c bch cu sn xut) v interferon- (IFN-, khi lng phn t khong 21 kDa, c nguyn bo si sn xut). C hai loi IFN- v IFN- c tc dng chng li s sinh sn ca t bo, c bit l IFN-, kch thch hot ng cc t bo dit t nhin (NK) lm tng biu hin cc phn t HLA11 lp I. IFN- c ng dng iu tr ung th c hiu qu (c bit l ung th mu c

tnh, ung th biu m t bo thn), iu tr bnh nhim virus vim gan B v C mn tnh (c th cha khi t 40-50% s bnh nhn). Interferon- (IFN-, c khi lng phn t khong 25 kDa, c sn xut t cc lympho T CD4+12 (h1), T CD8+ v cc t bo NK) hot ha cho s biu hin ca cc phn t HLA lp II, lm thc y s bit ha cc t bo mono thnh cc i thc bo. Cc interferon ring bit c cc phm vi hot ng khc nhau trong cc loi khc nhau. Interferon- chng t hiu qu chng li bnh hairy-cell leukemia v vim gan C. Ngoi ra, n cn c hot tnh chng vim gan B mn tnh, cng nh iu tr bu sinh dc v mt vi bnh ung th nh ung th mu v ty xng. Thuc xt mi cha interferon- cung cp mt s cht bo v chng bnh cm lnh do cc rhinovirus gy ra. 2.6 Vai tr Con ngi pht hin ra rng: Interferon ng vai tr l hng ro bo v u tin ca c th chng li virus v s pht trin bt thng ca t bo. Nhn chung, Interferon c 7 hot tnh sau: Khng virus; iu ha min dch; Chng tng sinh khi c hi; Kch thch s bit ha t bo; iu ha sinh trng t bo; Gii c; Khng t bin. T 7 hot tnh ny, con ngi vn dng vo vic bo ch cc loi thuc cha bnh an ton v hiu qu. Cc interferon (IFN) l nhng protein khng virus c cc t bo sn xut khi c th nhim mt loi virus gy bnh no . Interferon- v Interferon- c ba chc nng chnh.

Kch thch cc t bo cha b nhim virus khng vi virus thng qua c ch hot ha cc gene lm hn ch tng hp cc ARN thng tin v hn ch tng hp cc protein ca virus.

Cc cytokine ny kch thch hu ht cc t bo ca c th tng biu hin phc hp ha hp t chc chnh lp I (MHC I) nh cc t bo ny khng vi tc dng ca t bo NK. Mt khc, IFN- v IFN- cng kch thch cc t bo mi nhim virus tng biu hin (MHC I) v d b tiu dit bi cc t bo CD8 c t bo.

Nhng phn t ny c kh nng hot ha cc t bo NK, nh s hot ha m cc t bo git t nhin (khng phn bit i tng) s hot ng c chn lc hn, ngha l ch tiu dit cc t bo nhim virus. Tc ng khng virus Nhiu virus cha ARN hoc AND b c ch bi IFN. V d virus AND nh:

herpes virus loi 1 v 2, cytomegalovirus. V d virus ARN nh: rhinovirus v virus hp bo phi. Ngoi ra, IFN c tc ng hip lc vi nhiu tc nhn khng virus. Tuy nhin, mc khng virus khng ch ph thuc vo loi virus m cn vo c tnh ca t bo ch, loi IFN, v t l virus nhim vi s t bo. Interferon gip t bo khng vi s nhim virus bng cch tc ng n cc giai on khc nhau trong chu k nhn bn ca virus. N c th c ch cc giai on sm (v d gn, nhp bo qua trung gian th th, mt bao, phin m), s dich m cc ARN thng tin, v s trng thnh ca virus bao gm c vic m chi ca virion trn mng t bo. Cc bng chng khc cho thy IFN lm gim kh nng nhim ca cc virion th h sau. Tc ng khng t bo Interferon c th c ch s tng trng ca nhiu loi t bo bnh thng v t bo ung th in vitro. Tc dng khng tng trng IFN ch yu c tnh kim hm ( v d ngn cn s phn bo) hn l tiu dit (v d trc tip git cht t bo). Tnh nhy cm vi tc dng c ch ca IFN thay i, ngay c i vi cc t bo c cng

kiu m hc; iu ny c th do s khc nhau v s th th IFN hay i lc ca IFN trn th th. S phi hp cc IFN v tc nhn ha tr liu c tnh hip lc hay cng lc trong vic khng khi u. S hip lc l kt qu ca mt chui cc yu t tng tc phc tp, bo gm bn cht ung th, c ch tc ng cc tc nhn dit t bo, v ch liu dng IFN v tc nhn ha tr liu. Tc ng hip lc ph thuc nhiu vo ch s dng, v d dng IFN trc hoc sau tc nhn ha tr liu, hoc dng ng thi. Nhiu tc nhn ha tr liu khng c tc ng hip lc vi IFN. Mt kha cnh quan trng trong tc ng khng t bo ca IFN l n c kh nng iu ha trng thi bit ha ca t bo, c th l c ch hay kch thch. Interferon cng tng tc hip lc vi cc tc nhn c ch bit ha khc. S cm ng bit ha t bo ung th c vai tr nht nh trong tc ng khng ung th ca IFN v mc bit ha t bo t l nghch vi tc phn bo. Tc dng khng ung th Interferon kch thch h min dch ca c th chng li khi ung th. C ch ca chng cho n nay vn cha c hiu r mt cch y . Tuy nhin, n c th theo cc c ch sau: - Tr hon hoc dng s phn chia ca cc t bo ung th Gim kh nng t bo v ca cc t bo ung th i vi h min dch ca c th. Tng cng kh nng min dch ca c th. Interferon thng c s dng iu tr mt s loi ung th bao gm: ung th thn, u hc t c tnh, ung th xng, ung th hch, u lympho bo v bnh bch cu.. Tc ng iu ha min dch Nhiu chc nng min dch c th nh hng bi IFN. Cc p ng min dch c th qua trung gian t bo hay khng th. Interferon c th hot ha hay c ch c chc nng min dch t bo v dch th: thng nng cao th c ch v thp th hot ha. Hot tnh cc t bo NK cng nh hot tnh dit v c ch khi u ca i

thc bo c th c tng ln ng k bi c IFN alpha v IFN gamma. Cc t bo min dch khc c hot ha bi IFN bao gm lympho bo T, t bo c hot tnh tiu dit ph thuc khng th v t bo Mast. Cc interferon ca c ba loi cm ng s biu hin ca khng nguyn loi 1 ca phc hp ha hp m chnh ( MHC) v IFN gamma cm ng s biu hin ca khng nguyn MHC loi 2 . c tnh ny quan trng v khng nguyn MHC loi 1 ng vai tr trong s li gii ca cc t bo b nhim virus v t bo ung th, do lm tng s nhn din bi cc t bo T c. V chng u c kh nng hot ho t bo NK c th git cc t bo b nhim vi rt. Khng nguyn MHC loi 2 cn thit cho i thc bo hot ng nh t bo trnh din khng nguyn (antigen-presenting cell) do lm tng s ph by ca khng nguyn i vi t bo T helper. Interferon cn c th hot ho i thc bo chng li s nhim vi rt (hot ng khng vi rt bn trong) v git cc t bo khc nu chng b nhim vi rt (hot ng khng vi rt bn ngoi). Tuy nhin, c hai nhm khng nguyn MHC u quan trng t c p ng ti a. Tt c cc loi IFN dng nh c tc ng c ch sn xut khng th, mc d trong mt s iu kin nht nh v liu v thi gian c s gia tng sn xut khng th.

Interferon (IFN) l mt dng protein c chnh t bo trong c th sng tit ra khi c s xm nhim ca virus. Tuy c ch cha c bit nhng qua cc nghin cu tin lm sng v lm sng cho thy IFN ng vai tr quan trng trong vic ngn chn s pht trin ca virus trong c th. Hin nay, ng dng ni bt nht l dng IFN 2b trong iu tr vim gan siu vi C v vim gan siu vi B. 2.7 Sn xut interferon

Phn lp : 1. RNA phn on theo kch thc c phn lp t t bo bch cu ngi, sau phin m ngc v sau chn va v tr PstI ca plasmid Pbr322. 2. Khong 6.000 clon c to ra sau khi bin np vo vi khun Ecoli c chia thnh 12 l vi 512 dng trn mt l. 3. Mi l c lai vi ch phm mRNA ca IFN th.
4. mRNA a vo lai c tch khi th lai DNA mRNA v chuyn v h

thng tng hp protein ngoi bo. 5. Mi hn hp dc m iu kim tra hot tnh khng virus ca IFN. Cc ging c hot tnh IFN mang mt clon vi DNAbs lai vi mRNA ca IFN. 6. Cc ging dng c chia thnh tm nhm mi nhm c 64 dng v c kim tra li. qu trnh phn chia nhm ny c lp li cho n khi mt clon vi DNAbs hon chnh cho IFN ngi c xc nh.

Cu trc : IFN c m ha bi h 13 gen khc nhau. Cc thnh vin trong h IFN khc nhau v thnh phn v c tnh khng virus.

Promoter: Hu ht cc promoter c th iu khin mnh c s dng rng ri t operon lac v trp ca E. coli Ngoi ra cn c promoter tac mt bnar thit k in vitro gm vng 10 ca promoto lac v - 35 ca promoto trp.

Promoto tac v trc mi ci ch khc nhau mt cp bazo duy nht. Tac l promoto hot ng nht trong E. coli nhng t hot ng nht trong cc vi khun gram (-) khc. Nm l promote hot ng mnh th 2 trong E.coli v cng hot ng mnh cc vi khun khc. Ch : Khng c t bo nhn chun no c hiu qu vn nng thc hin cc bin i chnh xc trn mi protein. Trong mt s trng, mt s t bo ch gn nhng gc ng khng bnh thng( khng ph bin) vo ng (hoc sai) v tr acid amin to ra mt protein c tnh khng nguyn cc mnh hay mt protein thiu chc nng chnh xc. Tuy nhin d l mt protein c th khng t ti nhng tnh cht nghim ngt cn thit i vi mt tc nhn cha bnh nhng n vn c th c s dng cho nhng mc ch nghin cu hay mc ch cng nghip.

Ln men: Khi s dng h thng biu hin E.coli cho vic sn xut protein ti t hp cn cc iu kin sau:
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Oxi: i hi hm lng oxi ha tan ln, nhu cu oxi ti a trong ln

men ph thuc vo sinh khi t bo, v oxi ha tan km trong nc nn n phi c cung cp lin tc thng dng khng kh kh trng a vo mi trng ln men. Tuy nhin khi a khng kh vo s sinh bt do qu trnh sc kh (bt s gy kh khn trong qu trnh ln men nh: T l nhim cao, tc sinh trng ca t bo gim). V th cn phi theo di lng lin tc oxi ha tan. pH: 5,5 6,5. Ph mi trng phi c gim st lien tc bo m

pH khng b chnh lch qu ln trong qu trnh ln men. Nhit : Cn duy tr trong khong nhit nht nh v nm trong

khong ti u. Nu nhit mi trng ln men thp hn nhit ti u th t bo

s sinh trng chm v sn lng cho ra t bo gim. Ngc li, nu nhit ln men cao nhng cha n mc gy cht s lm gim nng sut v hot tnh ca protein.
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Ch khuy: L yu t quan trng nh hng n nhiu kha cnh

ca qu trnh ln men, bao gm c vic cung cp mi trng dinh dng y v ngn cn s tch t ca cc sn phm ph, c hi ca qu trnh trao i cht ti nhng ni c trn km trong ni ln men,
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Loi vi sinh vt bin i gen hay chng vi sinh vt cng c nh hng

rt ln n sn lng, nng sut, hot tnh cng nh cht lng sn phm ( E.coli c rt chng loi, chng E.coli thng c s dng cho qu trnh ny l chng IFN alpha 5 c chit t E.coli bng cch acid ha v trung ha v pH trung tnh. IFN trong dch chit c hp ph trn silica gel v gii ra bng cch h pH xung 2,0, bc ny lm tng hot tnh ln 10 ln. Sc k silica gel cng loi b phn ln acid nucleic trong phn on khng gn. Sc k Matrex Gel Blue A tinh ch thm 3,3 ln. Tip theo, IFN c hp ph trn nha trao i anion (v d DEAE Sepharose) v gii ra vi than pH t 8,0 n 6,0, lm tng hot tnh c hiu ln 10 ln na. Dch gii hp ph DEAE Sepharose c tinh ch thm trn ct khng th n dng c nh, YOK Sepharose. Vic gii hp ph c tin hnh vi sodium citrate 0,1M, pH 2,0. Hot tnh c hiu cui cng t c 1,9x108 IU /mg . Tch chit E.coli bng nghin c hc Kt lng bng polyethylenimine Kt lng vi sulfatammon Thm tch (tch cc thnh phn trong cht lng)

Sc k nh cht hp ph min dch (immunoadsorption) (cc khng nguyn n dng)

TNH HNH S DNG Hin nay, hn 3% dn s th gii b nhim virus gy vim gan siu vi C v hn 2 t ngi b nhim virus gy vim gan siu vi B. Tnh ring ti Vit Nam, s ngi ang nhim virus gy vim gan siu vi B v vim gan siu vi C chim n hn 25% dn s. C th thy nhu cu Interferon vn c xem l loi thuc c bn v duy nht c s dng rng ri trong iu tr bnh vim gan siu vi B v vim gan siu vi C, l rt cao. Vit Nam ang lu hnh 6 loi thuc interferon vi cc tn bit dc nh RoferonA (ca hng Roche, Thy S), IntronA (M), Shanthaferon (n ), La feron (Ucraina), Alpha Feron (Jedang - Hn Quc) v Superferon v IVACFeron (Interferon alpha 2b do Vin Vaccine v Sinh phm Nha Trang nhp v ng gi). Tt c cc loi thuc Interferon ny u phi nhp t nc ngoi, dn n vic iu tr bng Interferon (ko di trong vng 4-6 thng, mi tun iu tr 2-3 ln, mi ln tn 1-4 triu ng) l qu cao i vi mc thu nhp ca ngi Vit Nam. Trc tnh hnh thc t nh vy, cng nh theo chin lc ca Trung tm CNSH Thnh ph HCM l sn xut cc loi dc sinh hc c nhu cu cao trong nc vi gi thnh thp hn nhiu so vi gi nhp khu da trn cc bn quyn ca cc loi thuc ny ht hn v sp ht hn, Trung tm bc u nghin cu vic to dng v biu hin Interferon alpha 2b ca ngi trn h thng nm men Pichia pastoris.