Expression profile of Eph receptors and ephrin ligands in healthy human B lymphocytes and chronic lymphocytic leukemia B-cells
LEUKEMIA RESEARCH
Authors: Alonso-C, Luis M.; Trinidad, Eva M.; de Garcillan, Beatriz; Ballesteros, Monica; Castellanos, Milagros; Cotillo, Ignacio; Munoz, Juan J.; Zapata, Agustin G.
Abstract
Increasing information relates some Eph receptors and their ligands, ephrins (EFN), with the immune system. Herein, we found that normal B-cells from peripheral blood (PB) and lymph nodes (LN) showed a differential expression of certain Eph/EFN members, some of them being modulated upon in vitro stimulation including EFNA1, EFNA4, EphB6 and EphA10. In contrast, PB CLL B-cells showed a more heterogeneous Eph/EFN profile than their normal PB B-cell counterparts, expressing Eph/EFN members frequently found within the LN and activated B-cells, specially EFNA4, EphB6 and EphA10. Two of them, EphB6 and EFNA4 were further related with the clinical course of CLL patients. EphB6 expression correlated with a high content of ZAP-70 mRNA and a poor prognosis. High serum levels of a soluble EFNA4 isoform positively correlated with increasing peripheral blood lymphocyte counts and lymphadenopathy. These findings suggest that Eph/EFN might be relevant in normal B-cell biology and could represent new potential prognostic markers and therapeutic targets for CLL. (c) 2008 Elsevier Ltd. All rights reserved.
Molecular dissection of cone photoreceptor-enriched genes encoding transmembrane and secretory proteins
JOURNAL OF NEUROSCIENCE RESEARCH
Authors: Papal, Samantha; Monti, Christopher E.; Tennison, Mackenzie E.; Swaroop, Anand
Abstract
Cone photoreceptors mediate color perception and daylight vision through intricate synaptic circuitry. In most mammalian retina, cones are greatly outnumbered by rods and exhibit inter-dependence for functional maintenance and survival. Currently, we have limited understanding of cone-specific molecular components that mediate response to extrinsic signaling factors or are involved in communication with rods and other retinal cells. To fulfill this gap, we compared the recently-published transcriptomes of developing S-cone-like photoreceptors from the Nrl(-/-) mouse retina with those of rods and identified candidate genes responsible for cone cell functions and communication. We generated an in silico expression profile of 823 genes that encode candidate transmembrane and secretory proteins and are up-regulated in Nrl(-/-) cone photoreceptors compared to wild type cones. In situ hybridization analysis validated high expression of seven of the selected candidate genes in the Nrl(-/-) retina. To examine their relevance to cone function, we performed in vivo knockdown of Epha10 in the Nrl(-/-) retina and demonstrated aberrant morphology and mislocalization of the photoreceptor cell bodies. Thus, the receptor tyrosine kinase Ephrin type-A receptor 10 appears to influence cone morphogenesis. Our studies reveal novel cone-enriched genes involved in interaction of cones with other retinal cell types and provide a framework for examining molecular pathways associated with intercellular communication.