Microarray screening of RNA samples from two human myeloma and two human lymphoma cell lines

This laboratory studies the T cell recognition of glycolipid antigens, including the biochemical characterization of glycolipid antigens, the cell biology of glycolipid antigen presenting machinery, the chemical synthesis of self and foreign glycolipids, and the cellular immunology that might shed light on finding glycolipid targets for adjuvant and vaccine development. In myeloid patients, the suppression of NKT cells has been reported. This suppression is mediated by endogenous glycolipid antigens presented by CD1d, a non-classic MHC molecule. Tumor B cells express CD1d molecule and preserve the capacity in presenting glycolipid antigens to NKT cells. However, the identity of the tumor glycolipid antigens remain unknown. We recently identified isoglobotrihexosylceramide (iGb3), as one endogenous ligand for human NKT cells. We have also purified iGb3 from thymuses of pediatric patients. Thus we hypothesize that iGb3 might be directly linked to the NKT suppression in myeloma patients. The processing of iGb3 requires the “assembly line” of glycosyltransferases, the glycosidases and sphingolipid activator proteins. The loading of iGb3 antigen is dependent on lipid transfer proteins such as saposins, and the more recently characterized CD1e molecule. Thus we used the Glyo-chip approach to have a systemic survey of the above enzyme and protein components. We hope to find clues to help us in understanding the glycolipid antigen presentation in tumor B cells. EXPERIMENT: We purified RNA from 2 myeloma cell lines (U226 and 8226) by the RNAqueous kit from Ambion, TX. RNA was also purified from 2 lymphoma cell lines (Daudi and RL). 4 samples were provided to Core E of Consortium of Functional Genomics for Glyco-chip version 2 array.