LeGrue S J
Cancer Immunol Immunother. 1984;17(2):135-41. doi: 10.1007/BF00200050.
The purpose of this study was to examine (1) the association of tumor extract proteins with phospholipid vesicles of varying physiochemical properties, and (2) the adjuvant and carrier properties of liposome-borne tumor antigens in the in vivo induction of an antitumor immune response. Cell surface antigens of the 3-methylcholanthrene-induced fibrosarcoma of C3H/HeJ mice, MCA-F, were extracted using 2.5% 1-butanol. Crude and electrofocused antigen preparations capable of eliciting a protective antitumor immune response were used to prepare liposome vaccines. The incorporation of extract proteins into liposomes formed by butanol dialysis (BVD) was three- to five-fold greater than the encapsulation of protein into the aqueous compartment of multilamellar vesicles (MLV). The electrochemical properties of the BDV had a significant effect on the induction of an antitumor response: Antigens borne on negatively charged, but not uncharged, liposomes were effective in protecting hosts against supralethal tumor challenge, and displayed a specific activity 20- to 50-fold greater than soluble antigen. Antigens carried by MLV were not effective in generating an immunoprotective response. The lipophilic characteristics of butanol-extracted antigens allowed (1) the passive adsorption of immunoprotective tumor antigen onto the surface of preformed vesicles, and (2) adsorption of MCA-F antigen onto the surface of an antigenically distinct tumor MCA-D. In the latter experiment, adsorption of MCA-F-specific antigen onto MCA-D cells resulted in a change in the membrane antigen phenotype as measured by indirect immunofluorescence. Although butanol released a lipophilic moiety from cells which spontaneously reassociated with phospholipid bilayers, no evidence for a lipoidal antigen was obtained when tumor-derived lipids were used as immunogens. This study demonstrates that butanol-extracted tumor antigen is lipophilic without being a lipid, and that negatively charged liposomes can be effective as carriers and adjuvants for tumor antigens in the induction of an antitumor immune response.
（1）肿瘤提取物蛋白与具有不同物理化学性质的磷脂囊泡之间的关联；（2）脂质体携带的肿瘤抗原在体内诱导抗肿瘤免疫反应中的佐剂和载体特性。使用2.5%的正丁醇提取C3H/HeJ小鼠经3-甲基胆蒽诱导的纤维肉瘤（MCA-F）的细胞表面抗原。能够引发保护性抗肿瘤免疫反应的粗制和经电聚焦的抗原制剂被用于制备脂质体疫苗。通过正丁醇透析（BVD）形成的脂质体中提取物蛋白的掺入量比多泡囊泡（MLV）水相部分中蛋白的包封量高三至五倍。BDV的电化学性质对抗肿瘤反应的诱导有显著影响：带负电荷而非不带电荷的脂质体携带的抗原能有效保护宿主抵御超致死剂量的肿瘤攻击，且其比活性比可溶性抗原高20至50倍。MLV携带的抗原在产生免疫保护反应方面无效。正丁醇提取的抗原的亲脂特性使得：（1）免疫保护性肿瘤抗原被动吸附到预先形成的囊泡表面；（2）MCA-F抗原吸附到抗原性不同的肿瘤MCA-D表面。在后一个实验中，通过间接免疫荧光检测，MCA-F特异性抗原吸附到MCA-D细胞上导致膜抗原表型发生变化。尽管正丁醇从细胞中释放出一个亲脂部分，该部分会自发地与磷脂双层重新结合，但当使用肿瘤衍生脂质作为免疫原时，未获得脂质抗原的证据。本研究表明，正丁醇提取的肿瘤抗原是亲脂性的，但不是脂质，并且带负电荷的脂质体可作为肿瘤抗原的有效载体和佐剂用于诱导抗肿瘤免疫反应。
