Martín M G, Wu S V, Walsh J H
Department of Pediatrics, UCLA School of Medicine, Los Angeles, California 90095, USA.
Dig Dis Sci. 1997 May;42(5):1062-9. doi: 10.1023/a:1018853506830.
The intestine of the suckling rat has the unique capacity of absorbing immunoglobulins from maternal milk. We investigated intestinal Fc receptor mRNA expression and the absorption of orally administered antibodies to delineate the ontogeny and tissue specificity of this transport system. Duodenal expression of Fc receptor mRNA was at maximum levels between 1 and 19 days of age, but was not detectable during fetal life and in animals after weaning. Along the horizontal axis of the intestine, FcRn mRNA expression was maximum in the proximal duodenum and declined gradually in distal bowel. Similarly, absorption of orally administered antibody was low shortly after birth, but reached maximum levels at 14 days of age. By the time of weaning, antibody uptake had almost completely ceased. These data further delineate the temporal and spatial nature of the intestinal immunoglobulin transport system, and represent additional examples of how the intestinal Fc receptor is transcriptionally regulated.
乳鼠的肠道具有从母乳中吸收免疫球蛋白的独特能力。我们研究了肠道Fc受体mRNA的表达以及口服抗体的吸收情况，以阐明这种转运系统的个体发生和组织特异性。Fc受体mRNA在十二指肠的表达在出生后1至19天达到最高水平，但在胎儿期及断奶后的动物中无法检测到。沿着肠道横轴，FcRn mRNA表达在十二指肠近端最高，在远端肠段逐渐下降。同样，口服抗体的吸收在出生后不久较低，但在14日龄时达到最高水平。到断奶时，抗体摄取几乎完全停止。这些数据进一步阐明了肠道免疫球蛋白转运系统的时间和空间特性，并代表了肠道Fc受体转录调控方式的其他实例。
