
<ArticleTitle>Differential expression of <prot>cannabinoid <prot>CB(2)</prot> receptor</prot> mRNA in mouse immune cell subpopulations and following B cell stimulation.</ArticleTitle>
<AbstractText><prot>Cannabinoid <prot>CB(2)</prot> receptor</prot> is reported to be expressed in varying amounts in different human immune subpopulations. To examine the expression pattern of <prot>CB(2)</prot> in the mouse, immune cell subpopulations were purified and studied by semiquantitative Reverse Transcription-Polymerase Chain Reaction (RT-PCR). <prot>CB(2)</prot> mRNA was most abundant in splenic B cells, followed by macrophages and T cells. Furthermore, <prot>CB(2)</prot> was expressed in thioglycollate-elicited peritoneal macrophages, but not in resident peritoneal macrophages. In addition to these studies on receptor expression at basal activity, <prot>CB(2)</prot> mRNA expression was also studied following immune cell activation. Bacterial lipopolysaccharide stimulation downregulated <prot>CB(2)</prot> mRNA expression in splenocyte cultures in a dose-response manner, while stimulation through <prot>cluster of differentiation 40</prot> (<prot>CD40</prot>) using anti-<prot>CD40</prot> antibody upregulated the response and costimulation with <prot>interleukin-4</prot> attenuated the anti-<prot>CD40</prot> response. These results demonstrate that <prot>CB(2)</prot> mRNA expression differs among mouse immune subpopulations similar to what is observed in human immune cells. Furthermore, the results suggest that the signaling pathways activated by lipopolysaccharide and anti-<prot>CD40</prot> might have different effects on <prot>CB(2)</prot> mRNA expression.</AbstractText>
