Panneerselvam C, Haritos A A, Caldarella J, Horecker B L
Proc Natl Acad Sci U S A. 1987 Jul;84(13):4465-9. doi: 10.1073/pnas.84.13.4465.
The major cross-reacting peptide in human plasma detected with a radioimmunoassay (RIA) for thymosin alpha 1 was identified as prothymosin alpha, based on its elution properties in gel-filtration chromatography and its amino acid composition after purification by HPLC. A small quantity (less than 10%) of the total cross-reacting material was recovered in fractions corresponding to lower molecular weight thymosin alpha 1-like peptides. The total quantity of cross-reacting material detected in human blood, expressed as thymosin alpha 1 equivalents, was 11-14 pmol/ml (approximately 90% was recovered in the leukocyte fraction, approximately 10% was in the plasma fraction, and 1-2% was in the erythrocyte fraction). The peptide present in leukocytes was also identified as prothymosin alpha. After correction for the 5-times lower molar reactivity of prothymosin alpha in the thymosin alpha 1 RIA employed in these experiments, we estimate that the content of prothymosin alpha in human blood is 55-70 pmol/ml (0.6-0.8 microgram/ml). The relatively small quantities recovered in the erythrocyte and plasma fractions may be attributed to contamination of the former by leukocytes or to leakage from leukocytes into the plasma.
通过用于胸腺素α1的放射免疫分析（RIA）在人血浆中检测到的主要交叉反应肽，根据其在凝胶过滤色谱中的洗脱特性以及经高效液相色谱（HPLC）纯化后的氨基酸组成，被鉴定为前胸腺素α。在对应于较低分子量胸腺素α1样肽的级分中回收了少量（小于10%）的总交叉反应物质。以胸腺素α1当量表示，在人血液中检测到的交叉反应物质总量为11 - 14 pmol/ml（约90%在白细胞级分中回收，约10%在血浆级分中，1 - 2%在红细胞级分中）。白细胞中存在的肽也被鉴定为前胸腺素α。在这些实验中使用的胸腺素α1 RIA中，前胸腺素α的摩尔反应性比胸腺素α1低5倍，校正后，我们估计人血液中前胸腺素α的含量为55 - 70 pmol/ml（0.6 - 0.8微克/ml）。在红细胞和血浆级分中回收的量相对较少，可能归因于前者被白细胞污染或白细胞向血浆中的渗漏。
