Fox I H, Kaminska J, Edwards N L, Gelfand E, Rich K C, Arnold W N
Biochem Genet. 1980 Apr;18(3-4):221-34. doi: 10.1007/BF00484238.
Purine and pyrimidine metabolism was compared in erythrocytes from three patients from two families with purine nucleoside phosphorylase deficiency and T-cell immunodeficiency, one heterozygote subject for this enzyme deficiency, one patient with a complete deficiency of hypoxanthine-guanine phosphoribosyltransferase, and two normal subjects. The erythrocytes from the heterozygote subject were indistinguishable from the normal erythrocytes. The purine nucleoside phosphorylase deficient erythrocytes had a block in the conversion of inosine to hypoxanthine. The erythrocytes with 0.07% of normal purine nucleoside phosphorylase activity resembled erythrocytes with hypoxanthine-guanine phosphoribosyltransferase deficiency by having an elevated intracellular concentration of PP-ribose-P, increased synthesis of PP-ribose-P, and an elevated rate of carbon dioxide release from orotic acid during its conversion to UMP. Two hypotheses to account for the associated immunodeficiency--that the enzyme deficiency leads to a block of PP-ribose-P synthesis or inhibition of pyrimidine synthesis--could not be supported by observations in erythrocytes from both enzyme-deficient families.
对来自两个家族的三名嘌呤核苷磷酸化酶缺乏症和T细胞免疫缺陷患者、一名该酶缺乏症的杂合子受试者、一名次黄嘌呤 - 鸟嘌呤磷酸核糖基转移酶完全缺乏的患者以及两名正常受试者的红细胞中的嘌呤和嘧啶代谢进行了比较。杂合子受试者的红细胞与正常红细胞没有区别。嘌呤核苷磷酸化酶缺乏的红细胞在肌苷转化为次黄嘌呤的过程中存在障碍。具有正常嘌呤核苷磷酸化酶活性0.07%的红细胞，其细胞内PP - 核糖 - P浓度升高、PP - 核糖 - P合成增加，并且在乳清酸转化为UMP过程中二氧化碳释放速率升高，类似于次黄嘌呤 - 鸟嘌呤磷酸核糖基转移酶缺乏的红细胞。关于相关免疫缺陷的两种假说——即酶缺乏导致PP - 核糖 - P合成受阻或嘧啶合成受抑制——在两个酶缺乏家族的红细胞观察结果中均未得到支持。
