 directional resistivity measurements. Gangliosides are sialic acid containing glycosphingolipids composed of a complex carbohydrate moiety linked to a hydrophobic ceramide portion. Embedded within the outer leaflet of the cell membrane, the carbohydrate chain is exposed to the extracellular matrix. Qualitative and quantitative changes in ganglioside composition during cell differentiation and proliferation have been observed and seem to reflect the state of malignant transformation of cancers of neuroectodermal origin (Hakomori 1985). Malignant melanoma cells express a variety of complex gangliosides in addition to GM3, the major ganglioside in normal melanoctyes (Carubia et al. 1984). Altered ganglioside metabolism in melanoma causes additional expression of GD3, GD2, GM2, 9-0-Acetyl-GD3 and GT3 (Hamilton et al. 1993; Tsuchida et al., 1987). Treatment of patients with anti-GD3 monoclonal antibodies resulted in inflammation at the tumor site and partial regression of metastasis was seen occasionally, suggesting, that gangliosides are suitable targets for immune attack (Houghton et al., 1985). The generation of human MAb's reactive with GD3 from melanoma patients (Yamaguchi et al., 1987) support the idea, that gangliosides are potential immunogens as well. In studies aimed at inducing a humoral response against gangliosides in melanoma patients by active immunization, GM2/BCG vaccines seemed to be most effective (Livingston et al., 1987; Livingston et al., 1989). In a randomized study with 122 melanoma patients, who were disease-free after surgery, that it was showed that, out of 64 patients treated with BCG alone and 58 patients with GM2/BCG, the majority of patients (86%) receiving the GH2 vaccine produced antibodies. Patients that produced anti-GM2 antibodies had a significantly longer disease free and overall survival than antibody negative patients. Comparing the two arms of the trial, patients receiving the GM2/BCG vaccine had a 17% improvement in disease-free interval and 9% improvement in survival when compared to the BCG control group, though neither result was statistically significant (Livingston et al., 1993a). Unfortunately, the immune response was only of short duration, mostly IgM and of moderate titer. This suggested that GM2 was recognized as a T-cell independent antigen as a consequence of carbohydrate antigens (Livingston et al., 1989) and also because gangliosides are auto antigens expressed on
directional resistivity measurements. Gangliosides are sialic acid containing glycosphingolipids write of a complex carbohydrate moiety connect to a hydrophobic ceramide portion. Embedded within the outer booklet of the cell membrane, the carbohydrate chain is disclose to the extracellular matrix. Qualitative and quantitative changes in ganglioside composition during cellular telephone specialization and proliferation have been observed and seem to chew over the state of malignant transformation of cancers of neuroectodermal lineage (Hakomori 1985). Malignant melanoma cell express a variety of complex gangliosides in addition to GM3, the major ganglioside in normal melanoctyes (Carubia et al. 1984). Altered ganglioside metabolism in melanoma cause additional expression of GD3, GD2, GM2, 9 - 0 - Acetyl - GD3 and GT3 (Hamilton et al. 1993; Tsuchida et al. , 1987). Treatment of affected role with anti - GD3 monoclonal antibodies resulted in inflammation at the tumor site and fond regression of metastasis was visualize occasionally, suggesting, that gangliosides are suitable targets for immune fire (Houghton et al. , 1985). The generation of human MAb's reactive with GD3 from melanoma patients (Yamaguchi et al. , 1987) support the idea, that gangliosides are potential immunogens as well. In studies aimed at inducing a humoral response against gangliosides in melanoma patients by active immunization, GM2 / BCG vaccines seemed to be most effective (Livingston et al. , 1987; Livingston et al. , 1989). In a randomized study with 122 melanoma patient, who were disease - free after surgery, that it was show that, out of 64 patient treated with BCG alone and 58 patients with GM2 / BCG, the majority of patient (86 %) receiving the GH2 vaccine produced antibodies. Patients that grow anti - GM2 antibodies had a significantly longer disease free and overall survival than antibody negative affected role. Comparing the two arms of the trial, patients receive the GM2 / BCG vaccine induce a 17% improvement in disease - free interval and 9% improvement in survival when compared to the BCG control group, though neither result was statistically meaning (Livingston et al. , 1993a). Unfortunately, the immune response was only of short duration, mostly IgM and of moderate titer. This suggested that GM2 was recognized as a T - cell independent antigen as a consequence of carbohydrate antigen (Livingston et al. , 1989) and also because gangliosides are auto antigens expressed on
 digectional resistivity mexsurements. Gangliosidev are aialic azid containing glycosphingolmpidw comkjsed of a complex zarbohydrwte moiery lmnked to a hydro'gobic ccxamids porciin. Embedded wijhin the outar leaflet of dhd eell membrane, the carbohydrate chain is exppsfd to the extrwcelktlar matrix. Qualitative and quantitatibe chanjes in gangliosode composition during celp divferentiation and oroliferatiin hwce been obsefved and stek to refledt the state of malignant transwormacion of canxees lx neuroectovermal origin (Hakomori 1985). Manignant melanoma cellx eeprews a variety of complxx gangliosides in aqdition tm YM3, the major gangliosudw in tormdl mdoanuctgex (Darubiw ev al. 1984). Altersd gangliosude metabolism in mtlagima causes adsitionwl expression of GD3, GD2, GM2, 9-0-Acetyl-GD3 and GT3 (Hajilton et al. 1993; Tsuchida wt al., 1987). Treatment of pwtients wyth anti-GD3 monoclonal antibodies resulted in infldmmatmov au bme tjnog site and partial regression of metastasis wwa xevn occasionally, smggesting, that ganblloxydes are suitxble tcdgsts for immune attwck (Houdhton et al., 1985). Tre grneration of human MAb's reaxtive with GB3 feom melanoma patieuts (Yamaguchn et ak., 1987) sulport the idea, that ganyliosises are potfntial imjjnogens as well. Kn xtgdies aimed at inducing a rumoral rxsponxe agaivst banglijsides in lelanoma patients by actlve ilmgnization, HM2/BCG vaccines seemed to be mosv effective (Lovhngvton et cl., 1987; Liyingston et al., 1989). In a randomizgd study cith 122 oelanoma pztients, who were dysease-free afdgr surgery, thet it was shoqed rhat, oug of 64 patients yreated wptk BCG alobe and 58 patients wlth GO2/GCG, the majoritv if patients (86%) reveixind nhe GR2 vaccine progucea avyibodkes. Patientw thay produced anti-GM2 andibosies had a signifivaktly longgr diseasq free and ovrrall survival thaj antmbody iegatife katients. Comparing the two arms of the tgiaj, patients rqceiying the GM2/BCG vaccine had a 17% improvement in disease-fcee interval and 9% improcement in survival chtn compared tp the BCG contsol group, though neirher result was suatistically significanf (Livitgstoj et al., 1993a). Unfortunately, the immune response was only of short duration, mowtly IjM and of modsratr titvr. Chix suggqstev vhat GM2 was recogmized as a T-cell independent anvigen as a cjnsequence of carbohydrate amtkgens (Livingsjon et al., 1989) and also becauss ganglipsides are auto antigens expresxed on
directional resistivity measurements. Gangliosides are sialic acid composed a complex moiety linked to within outer leaflet of cell membrane, the chain is exposed to the extracellular Qualitative and quantitative changes in ganglioside composition during cell differentiation and proliferation have observed and seem to reflect the state of malignant transformation of cancers of origin 1985). melanoma express a variety of complex gangliosides in addition to GM3, the major ganglioside in normal melanoctyes et al. 1984). Altered ganglioside metabolism in melanoma additional expression of GD3, GM2, 9-0-Acetyl-GD3 and GT3 (Hamilton al. Tsuchida et 1987). of with anti-GD3 monoclonal resulted in inflammation at the tumor site and partial regression of metastasis was seen occasionally, suggesting, that are suitable immune attack et 1985). generation of human with GD3 from melanoma patients (Yamaguchi support the idea, that gangliosides are potential immunogens well. In aimed at inducing a humoral response gangliosides in melanoma patients by active immunization, GM2/BCG seemed to be most effective (Livingston et al., 1987; Livingston et al., 1989). In a with 122 melanoma patients, were disease-free after that was that, of 64 treated with BCG alone and 58 patients with GM2/BCG, the majority patients (86%) receiving the GH2 vaccine produced antibodies. Patients that antibodies a significantly longer free and overall survival antibody patients. Comparing the two the patients vaccine a improvement in disease-free interval 9% improvement in survival when to the BCG control statistically significant (Livingston et al., 1993a). Unfortunately, the response was only of short duration, mostly and of moderate titer. This suggested that GM2 was recognized as a independent antigen consequence of carbohydrate antigens (Livingston et al., 1989) also because gangliosides are antigens expressed on
 directional resistivity meaSurements. GAngliOsiDes ArE siaLic aCid containing gLYcosPhingolipids composed of A compLeX CarbOHyDrate Moiety lINkED To a HyDrOphObIC cEramiDe pOrtion. EMbedded witHin ThE outer leafleT Of The cell memBraNe, the carbohyDraTe chaiN iS exPOsed tO thE extrAcelluLAr matrIx. QualitaTiVE and quANtitatiVE ChAngeS in ganglioside comPOsITion during cell DifferEnTIaTIOn aNd pRoliferatiOn Have bEEn obserVEd AND SeeM To reflect the sTate of maligNAnt TransfOrMatIOn of caNcers Of NEurOectodermal OrigIn (HakomorI 1985). MaligNAnt melaNOma cellS expreSs a VarIety OF cOmPleX gANglIOsIdeS In aDdition tO Gm3, tHe majOr gaNGLIOsidE in NormAl melAnoctyes (CarubIa eT al. 1984). ALTerEd ganGliosIde mEtAboliSm in meLanomA cAuses additional ExprEssion of Gd3, GD2, gM2, 9-0-aceTyL-GD3 anD gT3 (HamiLtoN et Al. 1993; TsuchIda et al., 1987). tReaTmENT Of Patients with anti-GD3 MoNOClOnal antiBodies REsUlTEd in inflAmMatIon aT THe tumOr siTE aNd partiaL regreSSiOn Of metasTaSis was SeEn oCcaSionaLLy, suGgestiNg, that gaNglioSIdes are suitablE Targets for immUNe ATTaCK (HouGhtOn et al., 1985). The geNeraTIon oF humAN Mab's REactiVe witH Gd3 FrOM melanoma patients (YaMaGuchi eT al., 1987) suPport the idea, tHat ganglioSIDEs are potEntiAL iMMunogens as well. in stuDies aimed aT Inducing A humoRal respoNse againsT GAngliosiDes In mElaNomA PAtIents by active IMMuniZaTion, GM2/BcG vAccines SeeMed To bE moSt Effective (livingstOn Et Al., 1987; liVinGston ET al., 1989). In a raNdOmiZeD stUdy wiTH 122 melanOma paTienTs, WhO WerE diseasE-FrEE AfteR sUrGery, ThaT iT was sHoweD ThaT, out of 64 pAtients trEatED witH BcG Alone anD 58 patients with gM2/bCG, the majoRiTy oF patieNTS (86%) receiviNg the GH2 vaccine produced aNTibodieS. PaTientS thaT produced AntI-GM2 antIboDIes had A signiFicanTlY loNGEr disEASe FreE aNd overall sURVivAl thaN aNtibOdy negaTive patients. ComparINg tHe two arms of thE trIal, pATIeNts REcEIviNg THe Gm2/bcG vaccine had a 17% imProvement iN dISeAse-free intERvaL aNd 9% improVement iN survIVal when Compared tO the BCG coNtRol gROUp, tHough neithEr result Was statisTIcallY SiGnifiCanT (LivinGsTon Et al., 1993a). unfortUNatEly, thE immunE rEsponsE was oNlY of short Duration, mostly IgM and of mOderatE titeR. ThIs suggestEd tHAt Gm2 was recogNizeD as a T-cell iNdePenDent aNtiGEn as a ConsEQuEncE Of carBohyDRate antigENs (livINGsTon et al., 1989) and aLSO BecAuse gAngLIosideS are Auto antigens expreSSed on
 directional resistivity m easurement s. Ga ngl ios id es a re s ialic acid con t aini ng glycosphingolipidscompo se d  ofa  c omple x carbo h yd r a temo ie tyli n ke d toa h ydropho bic cerami depo rtion. Embed d ed  within th e o uter leaflet  of  the c el l m e mbran e,the c arbohy d rate c hain is e xp o sed to the ext r a ce llul ar matrix. Qualit a ti v e and quantita tive c ha n ge s ingan glioside c om posit i on duri n gc e l l d i fferentiation  and prolif e rat ion ha ve  be e n obse rvedan d  se em to refle ct t he stateof mal i gnant t r ansform ationofcan cers of  n eur oe c tod e rm alo rig in (Hako mo ri  1985 ). M a l i g nant  me lano ma ce lls express a  va riet y  of  comp lex g angl io sides  in ad ditio nto GM3, the maj or g angliosid e i nnor ma l mel a noctye s ( Car ubia et  al. 19 8 4).  A l t e re d ganglioside meta bo l i sm  in mela noma c a us es addition al  ex pres s i on of  GD3 ,  G D2, GM2,  9-0-A c et yl -GD3 an dGT3 (H am ilt onet al .  199 3; Tsu chida et  al., 1987). Treatme n t of patients wi t h  a n ti-G D3monoclonalanti b odie s re s ul ted in in flamm at i on at the tumor site a nd  parti al re gression of m etastasisw a s  seen oc casi o na l ly, suggesting , tha t ganglios i des aresuita ble targ ets for i m m une atta ck(Ho ugh ton e tal., 1985). T h e  gen er ation o f h uman MA b's  re act ive  w ith GD3 f rom mela no ma  p at ien ts (Y a maguchiet  al .,  19 87) s u pportthe i dea,  t ha t  ga ngliosi d es a re p ot en tial  im mu nogen s as wel l. In s tudies ai med at i nd uc ing a h umoral respon se  against g an gli osides i n melano ma patients by active i m munizat ion , GM2 /BCG  vaccines  se emed t o b e  mosteffect ive ( Li vin g s ton e t al .,19 87; Living s t onet al .,  198 9). Ina randomized study wit h 122 melanom a p atie n t s,  wh o  w e redi s eas e - free after surg ery, thatit wa s showed t h at,  o ut of 6 4 patie nts t r eated w ith BCG a lone and58  pat i e nts  with GM2/ BCG, the  majority of pa t ie nts ( 86% ) rece iv ing  theGH2 va c cin e pro ducedan tibodi es. P at ients th at produced anti-GM2 an tibodi es ha d a  signific ant l y l onger dis ease  free andove ral l sur viv a l tha n an t ib ody negat ivep atients.C om par i n gthe two arm s o f t he tr ial ,  patie ntsreceiving the GM2 / BCG vaccine ha d a1 7 % i mpr o veme nt  in disease-fr eein t e rval and  9 % improveme nt in su rv i val w hen co mpared  to the B CG contro l gr oup , thoughnei th e r resul twa s  stati stic al ly sig nifica n t (L i v ingston et al.,1993a ) .  Unfo r tun ately ,the imm u ne r esponse wa s only of s hort d urat ion,mostlyIg M andofmo derate tit e r. This s ugges ted tha tGM2was  recog nize d as aT-ce ll  in dependent a nt i ge na s a  con seque nc e of  carbohyd r ate anti gen s  (Livin gs ton e t al., 19 8 9 ) and also  be cause g anglioside s  are au t o ant igensexpres sed on
 directional_resistivity measurements._Gangliosides are sialic acid_containing glycosphingolipids_composed_of a_complex_carbohydrate moiety linked_to a hydrophobic_ceramide portion. Embedded within_the outer leaflet_of_the cell membrane, the carbohydrate chain is exposed to the extracellular matrix. Qualitative and_quantitative_changes in_ganglioside_composition_during cell differentiation and proliferation_have been observed and seem_to reflect_the state of malignant transformation of cancers of_neuroectodermal_origin (Hakomori 1985)._Malignant melanoma cells express a variety of complex gangliosides_in addition to GM3, the major_ganglioside in normal_melanoctyes_(Carubia_et al. 1984). Altered_ganglioside metabolism in melanoma causes additional_expression of GD3, GD2, GM2, 9-0-Acetyl-GD3_and GT3 (Hamilton et al. 1993; Tsuchida_et al., 1987). Treatment of patients_with anti-GD3 monoclonal antibodies resulted_in inflammation_at the tumor site and_partial regression of_metastasis was_seen occasionally, suggesting,_that gangliosides are suitable targets for_immune attack (Houghton_et al., 1985). The generation of_human_MAb's reactive with_GD3_from_melanoma patients_(Yamaguchi et al.,_1987)_support the_idea,_that gangliosides are potential immunogens as_well._In studies aimed at inducing a humoral_response against gangliosides in_melanoma_patients by active immunization,_GM2/BCG vaccines seemed to be_most effective (Livingston et al., 1987;_Livingston et_al., 1989)._In a randomized study with 122 melanoma patients, who were disease-free_after surgery, that it was showed_that, out of 64_patients treated_with_BCG alone and_58_patients with_GM2/BCG, the majority of patients (86%) receiving_the GH2_vaccine produced antibodies. Patients that produced_anti-GM2 antibodies had a_significantly_longer disease free and overall survival_than antibody negative patients. Comparing the_two arms of the trial,_patients_receiving_the GM2/BCG vaccine had a_17% improvement in disease-free interval and_9% improvement in_survival when compared to the BCG control_group,_though neither result was statistically significant_(Livingston_et al., 1993a). Unfortunately, the immune_response_was_only of short duration, mostly_IgM and of moderate titer. This_suggested that GM2 was recognized as a T-cell independent_antigen as a_consequence of carbohydrate antigens (Livingston_et_al.,_1989) and also because gangliosides are auto antigens expressed on