This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The above paper describes binding of various glycoclusters and glycodendrimers, respectively, to the rat natural killer cell receptor NKR-P1A and its precipitation. Unfortunately, an investigation has discovered recently that the author responsible for the immunological experiments – Prof. Karel Bezouška - has been fabricating the results and most plausibly also manipulating experimental material in collaborating laboratories. Based on the findings of the Joint Ethical Committee of the Institute of Microbiology, Acad. Sci. of the Czech Republic, and Charles University in Prague and based on Prof. Bezouška's written declaration sent to the Director of the Institute of Microbiology, September 19, 2013 (in which he pleads guilty of his scientific misconduct) the authors are forced to consider all the data on the binding of saccharides to the NKR-P1 receptor erroneous. Therefore, the authors request the retraction of the above publication. The authors of this article would like to apologize to all affected parties. Link to the institute's press release: http://www.biomed.cas.cz/mbu/doc/VyjadreniEK.PDF