Saptogino A, Becker W, Wolf F
Department of Nuclear Medicine, University of Erlangen-Nürnberg, FRG.
Nuklearmedizin. 1990 Mar;29(2):54-8.
99mTc-labelled polyclonal human immunoglobulin (HIG) has been shown to be able to localize inflammatory sites. Hypothetically these immunoglobulins bind directly to bacteria, HIG binds directly to Fc-receptors on the surface membrane of leucocytes or HIG simply passes vessels of increased permeability. To collect further information experiments were carried out in vitro with the blood of human volunteers. 0.5 mg 99mTc-HIG, 2 mg 99mTc-human albumin and 0.5 mg 99mTc-labelled murine monoclonal antigranulocyte antibodies were added to in vitro isolated human "mixed" leucocyte pellets and to 30 ml whole blood of 6 healthy volunteers. The whole blood and the directly labelled leucocyte pellet were layered and separated on a discontinuous Percoll/plasma gradient. The activity distribution was measured within the gradient. The 99mTc-HIG labelled gradients showed a significant uptake of the activity within the monocyte band whereas the 99mTc-albumin gradients showed no specific albumin uptake in any cellular band. The 99mTc-antibody labelled gradients showed a significantly increased uptake on granulocytes. It is concluded that in man a specific monocyte-associated uptake and binding mechanism of 99mTc-HIG plays an important role in the localisation of inflamed sites.
99m锝标记的多克隆人免疫球蛋白（HIG）已被证明能够定位炎症部位。据推测，这些免疫球蛋白直接与细菌结合，HIG直接与白细胞表面膜上的Fc受体结合，或者HIG只是通过通透性增加的血管。为了收集更多信息，对人类志愿者的血液进行了体外实验。将0.5毫克99m锝-HIG、2毫克99m锝-人白蛋白和0.5毫克99m锝标记的鼠单克隆抗粒细胞抗体添加到体外分离的人类“混合”白细胞沉淀以及6名健康志愿者的30毫升全血中。将全血和直接标记的白细胞沉淀在不连续的Percoll/血浆梯度上分层并分离。测量梯度内的活性分布。99m锝-HIG标记的梯度显示单核细胞带内有明显的活性摄取，而99m锝-白蛋白梯度在任何细胞带中均未显示出特异性白蛋白摄取。99m锝-抗体标记的梯度显示粒细胞摄取明显增加。结论是，在人类中，99m锝-HIG的特异性单核细胞相关摄取和结合机制在炎症部位的定位中起重要作用。
