Microarray clustering

Multiple sclerosis (MS) is a devastating disease of the CNS that produces demyelination and inflammation. It is believed that its pathogenesis involves an immune reaction against various components of the myelin sheath. In a study by Lock et al. (2002), the gene expression patterns of brain lesions obtained during autopsies of MS patients were examined by microarray cluster analysis. A total of 1080 genes (from 7026 represented... 

We thank Dr. Richard R. Almon and Dr. Debra C. DuBois for collaborations on genomic assays and microarray cluster analysis. This work was supported by NIH Grants GM 24211 and GM 57980. 

Figure 2.8 Microarray cross-platform showing differentially expressed gene clusters obtained from Amersham, Agilent, and Affymetrix products. (From Barczak, A., etal., Genome Res., 13, 1775-1785, 2003 [Copyright 2003 Cold Spring Harbor Laboratory Press] and Tan, P.K. etal.. Nucleic Acid Res., 31(19), 5676-5684, 2003. With permission.)...

In summary, we find gene expression profiling with microarrays to be an exceptionally powerful and profound analytical fool. Not only is the technique useful for global analyses, for example, of mefabolic pathways and their interrelationships, but it also has the ability to focus upon (albeit assisted by clustering) and track important singular events that would otherwise remain hidden under a genomic backdrop. 

Figure 5.22 Investigating the pathogenesis of glaucoma based upon microarray gene expression clustering. (From Hernandez, M.R., GLIA, 38 45-64, 2002. With permission.)...

In the case of immunoglobulin, microarray data indicated the opposite effect that the Fc-receptor is elevated in chronic MS but not in acute lesions. Using Fcy-receptor knockout mice, the disease was found to be absent. Inter-venous immrmoglobulin therapy in the EAE mouse model was reported (see Lock, 2002, Reference 29). In summary. Lock et al. were able to apply the results of microarray-based gene expression clustering of a human disease pathological state (acute vs. chronic MS) to successfully identify fherapeutic targets for an animal model (EAE) potentially applicable to the human condition. 

Belov L, de la Vega O, dos Remedios CG, Mulligan SP, Christopherson RI. Immunophenotyping of leukemias using a cluster of differentiation antibody microarray. Cance Res 2001 61(ll) 4483-4489. 

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