Carbohydrates are more than an energy-storage. They are ubiquitously found on cells and most proteins, where they encode biological information. Lectins bind these carbohydrates and are essential for translating the encoded information into biological functions and processes. Hundreds of lectins are known, and they are found in all domains of life. For half a century, researchers have been preparing variants of lectins in which the binding sites are varied. In this way, the traits of the lectins such as the affinity, avidity and specificity towards their ligands as well as their biological efficacy were changed. These efforts helped to unravel the biological importance of lectins and resulted in improved variants for biotechnological exploitation and potential medical applications. This review gives an overview on the methods for the preparation of artificial lectins and complexes thereof and how reducing or increasing the number of binding sites affects their function.

碳水化合物不仅仅是一种能量储存。它们普遍存在于细胞和大多数蛋白质上，在那里它们编码生物信息。凝集素与这些碳水化合物结合，对于将编码信息转化为生物学功能和过程至关重要。已知有数百种凝集素，它们存在于生活的各个领域。半个世纪以来，研究人员一直在制备结合位点不同的凝集素变体。这样，凝集素对配体的亲和力、亲合力和特异性等特性以及它们的生物学功效都发生了变化。这些努力有助于揭示凝集素的生物学重要性，并导致改进的变体用于生物技术开发和潜在的医学应用。