Oyen W J, Claessens R A, van der Meer J W, Corstens F H
Department of Nuclear Medicine, University Hospital Nijmegen, The Netherlands.
J Nucl Med. 1992 Mar;33(3):388-94.
The purpose of this study was to evaluate the role of both protein and radionuclide in the accumulation of 111In-labeled human immunoglobulin G (IgG) in infectious foci. In rats with a calf muscle infection, biodistribution was determined 2, 6, 24, and 48 hr after injection of a radiopharmaceutical. For IgG, human serum albumin (HSA) and human immunoglobulin A (IgA), all labeled with 111In, target-to-background (T/B) ratios were similar throughout the study. However, absolute abscess uptake of 111In-IgA was significantly lower. For IgG labeled with 111In, 123I, or 99mTc, similar T/B ratios were found up to 24 hr. After 48 hr, the T/B ratio of 111In-IgG was significantly higher than the T/B ratio of 123I-IgG. The absolute abscess uptake of 111In-IgG was higher than that of 99mTc-IgG at 24 hr and 123I-IgG at 48 hr. In conclusion, the radionuclide appears to be of major importance in the accumulation of radiolabeled proteins in infectious foci. Protein mainly influences blood clearance and distribution in organs. The Fc-gamma receptor is not crucial for accumulation in infectious foci.
本研究的目的是评估蛋白质和放射性核素在111In标记的人免疫球蛋白G（IgG）在感染灶蓄积中的作用。在患有小腿肌肉感染的大鼠中，注射放射性药物后2、6、24和48小时测定生物分布。对于均用111In标记的IgG、人血清白蛋白（HSA）和人免疫球蛋白A（IgA），在整个研究过程中，靶本比（T/B）相似。然而，111In-IgA在脓肿中的绝对摄取量显著较低。对于用111In、123I或99mTc标记的IgG，在24小时内发现相似的T/B比。48小时后，111In-IgG的T/B比显著高于123I-IgG的T/B比。111In-IgG在脓肿中的绝对摄取量在24小时时高于99mTc-IgG，在48小时时高于123I-IgG。总之，放射性核素似乎在放射性标记蛋白质在感染灶的蓄积中起主要作用。蛋白质主要影响血液清除率和在器官中的分布。Fc-γ受体对在感染灶的蓄积并不关键。
