Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023241 (Legionella)
 6,990 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have reported that injection of marijuana cannabinoids, such as Delta(9)-tetrahydrocannabinol (THC), into mice, followed by infection with Legionella pneumophila (Lp), suppresses the development of cell-mediated immunity T helper 1 (Th1) activity. These effects are accompanied by suppression of interleukin (IL)-12 and interferon (IFN) gamma production and enhancement of IL-4 production suggesting THC-induced T helper cell biasing. In the current report, other T helper cell biasing mechanisms were studied. Mice were injected with THC followed 18 h later by a challenge infection with Lp. Two-hour post-infection, spleens were removed and analyzed for mRNA to either IL-12Rbeta2 or GATA3 gene products. The results showed that THC suppressed IL-12Rbeta2 but increased GATA3. Receptor antagonists for CB1 (SR141716A, SR1) and CB2 (SR144528, SR2) were also injected to analyze the involvement of cannabinoid receptors. It was determined that SR1 attenuated the THC suppression of IL-12Rbeta2, while SR2 attenuated the increase in GATA3 mRNA. These results suggest that THC suppresses Th1 biasing activity such as IL-12Rbeta2 by a CB1 mediated mechanism and enhances the Th2 biasing activity, GATA3, by a CB2 mechanism. This dichotomy of receptor involvement might result from differential expression and/or signaling function of CB1 and CB2 on Th1 and Th2 cells.
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PMID:Cannabinoid receptors and T helper cells. 1474 35

Legionella pneumophila infection of mice induces proinflammatory cytokines and Th1 immunity as well as rapid increases in serum levels of IL-12 and IFNgamma and splenic IL-12Rbeta2 expression. Delta-9-tetrahydrocannabinol (THC) treatment prior to infection causes a shift from Th1 to Th2 immunity and here we demonstrate that CB(1) and CB(2) cannabinoid receptors mediate different aspects of the shift. Using cannabinoid receptor antagonists and cannabinoid receptor gene deficient mice (CB(1) (-/-) and CB(2) (-/-)), we showed that both CB(1) and CB(2) receptors were involved in the THC-induced attenuation of serum IL-12 and IFNgamma. IFNgamma production is dependent upon signaling through IL-12Rbeta2 (beta2) and THC treatment suppressed splenic beta2 message; moreover, this effect was CB(1) but not CB(2)-dependent from studies with receptor antagonists and CB1(-/-) and CB2(-/-) mice. Furthermore, observed increases in IL-4 induced by THC, were not involved in the drug effect on beta2 from studies with IL-4 deficient mice. The GATA-3 transcription factor is necessary for IL-4 production and is selectively expressed in Th2 cells. GATA-3 message levels were elevated in spleens of THC-treated and L. pneumophila-infected mice and the effect was shown to be CB(2) but not CB(1)-dependent. Furthermore, GATA-3 regulatory factors were modulated in that Notch ligand Delta4 mRNA was decreased and Jagged1 increased by THC also in a CB2-dependent manner and splenic NFkappaB p65 was increased. Together, these results indicate that CB(1) and CB(2) mediate the THC-induced shift in T helper activity in L. pneumophila-infected mice, with CB(1) involved in suppressing IL-12Rbeta2 and CB(2) involved in enhancing GATA-3.
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PMID:CB(1) and CB(2) cannabinoid receptors mediate different aspects of delta-9-tetrahydrocannabinol (THC)-induced T helper cell shift following immune activation by Legionella pneumophila infection. 1879 85