分泌抗人IL－3、IL－5和GM－CSF受体β链人工合成多肽McAb杂交瘤细胞系的建立

PREPAKATION AND IDENTIFICATION OF HYBRIDOMAS SECRETING MOUSE McAbS AGAINST COMMONβCHAIN OF GMCSF、IL-3 AND IL-5 RECEPTOR

制备抗人ＩＬ－３、ＩＬ－５和ＧＭ－ＣＳＦ受体β链人工合成多肽Ｄ１、Ｄ２、Ｄ３和Ｄ４共３９株ＭｃＡｂ杂交瘤细胞系，并对其分泌ＭｃＡｂ的类与亚类、效价、特异性和上清的阻断活性进行了初步分析。ＭｃＡｂ上清阻断活性结果提示，至少部分ＭｃＡｂ可与天然的受体β链发生免疫反应，并可能有阻断ＧＭ－ＣＳＦ与β链结合作用。此外，还应用人工合成多肽片段，确定了２３株抗Ｄ１ＭｃＡｂ的大致识别表位。这些ＭｃＡｂ杂交瘤细胞系的获得为进一步研究受体β链的表达与调控、β链的结构与功能以及对于诊断和研究髓样白血病细胞的病理等均有十分重要的意义。

The aminoacid sequence of the common βsubunit of GM-CSF、IL-3 and IL-5 deducted from cloned cDNA predicated that this protein consists of 882 aminoacids plus a 16 amino acid signal sequence. Based on this aminoacid sequence, four peptides of D1、D2、D3 and D4, which comparised aminoacid residues 9～14, 115～225, 226～325 and 326～422, were synthesized respectively. A panel of monoclonal antibodies(McAbs)against receptor chain peptides D1、D2、D3 and D4 respectively were raised. The classes and subclasses, specificity and ascieties titer of McAbs were identified. It was shown that some hybridoma culture supernatants could block the proliferation of DMSO-iduced HL60 cells promoted by GM-CSF.Moreover,the mechanism by which McAbs to distinct epitopes had cross-reaction was analysed with a computer program. And the epitope maps of McAb against D1 were identified by reacting with sythetic fragments of βchain residues 45～75, 56～75 and 66～75. All McAbs against βchain might be useful for studing the pathogenesis of myeloid leukemic cells and investigation of signaling pathways stimulated by these cytokines.