Product Citations: 6

Immunotherapy is considered one of the most promising treatments for lung cancer. The cell signalling molecules melanoma differentiation-associated protein 5 (MDA5) and retinoic acid-inducible gene I protein (RIG‑I) are essential receptors that recognise intracellular pathogen-associated nucleic acids, whereas interferon regulatory factor 3 (IRF3) controls the expression of innate immunity-associated genes in macrophages. However, the innate immune response to polyinosinic:polycytidylic acid [Poly(I:C)] in lung cancer remains to be elucidated. In the present study, western blot analysis, reverse transcription-quantitative polymerase chain reaction, RNA interference, IRF3 plasmid construction, ELISA and apoptosis analysis were employed to study the innate immune response and apoptosis of non‑small cell lung cancer (NSCLC) cells. Poly(I:C) transfection in NSCLC cells triggered apoptosis via the extrinsic apoptotic pathway, and activated the innate immune response by promoting interferon-β and C-X-C motif chemokine ligand 10 expression. Treatment with the IκB kinase ε/tumour necrosis factor receptor-associated factor family member-associated nuclear factor-κB activator-binding kinase 1 inhibitor BX795, which inhibits IRF3 phosphorylation, or transfection with small interfering RNA/short hairpin RNA to downregulate MDA5, RIG‑I or IRF3, prior to Poly(I:C) transfection inhibited the innate immune response and apoptotic pathway. Conversely, IRF3 overexpression promoted activation of the apoptotic pathway, thus indicating that the MDA5/RIG‑I/IRF3 axis may mediate responses to Poly(I:C) transfection. Furthermore, phosphorylation of the transcription factor signal transducer and activator of transcription 1 (STAT1) was associated with the alterations in IRF3 phosphorylation and apoptosis, thus suggesting that STAT1 may be involved in Poly(I:C)-induced apoptosis. In NSCLC surgical samples, MDA5, RIG‑I and IRF3 were highly expressed, whereas the expression levels of phosphorylated‑IRF3 were reduced. These findings indicated that the function of the MDA5/RIG‑I/IRF3 axis may be impaired in some lung cancers. In conclusion, the present findings suggested that the MDA5/RIG‑I/IRF3 axis, which is associated with innate immunity, is intact in NSCLC cells, and IRF3 is involved in regulating the apoptotic pathway in NSCLC cells.

  • Cancer Research
  • Immunology and Microbiology

We investigated whether the previously reported preventive effect of maternal ω-3 fatty acid supplementation on IgE-associated allergic disease in infancy may be mediated by facilitating a balanced circulating Th2/Th1 chemokine profile in the infant. Vaccine-induced immune responses at 2 y of age were also evaluated. Pregnant women, at risk of having an allergic infant, were randomized to daily supplementation with 1.6 g eicosapentaenoic acid and 1.1 g docosahexaenoic acid or placebo from the 25th gestational week through 3.5 mo of breastfeeding. Infant plasma was analyzed for chemokines (cord blood, 3, 12, 24 mo) and anti-tetanus and anti-diphtheria IgG (24 mo). High Th2-associated CC-chemokine ligand 17 (CCL17) levels were associated with infant allergic disease (p < 0.05). In infants without, but not with, maternal history of allergy, the ω-3 supplementation was related to lower CCL17/CXC-chemokine ligand 11 (CXCL11) (Th2/Th1) ratios (p < 0.05). Furthermore, in nonallergic, but not in allergic infants, ω-3 supplementation was linked with higher Th1-associated CXCL11 levels (p < 0.05), as well as increased IgG titers to diphtheria (p = 0.01) and tetanus (p = 0.05) toxins. Thus, the prospect of balancing the infant immune system toward a less Th2-dominated response, by maternal ω-3 fatty acid supplementation, seems to be influenced by allergic status.

  • Endocrinology and Physiology
  • Immunology and Microbiology

IFN-gamma is a pleiotropic cytokine importantly involved in the development of skin inflammatory responses. Epidermal keratinocytes are extremely susceptible to IFN-gamma action, but, once transduced with the suppressors of cytokine signaling (SOCS)1 molecule, they can no longer express a number of IFN-gamma-inducible signal transducer and activator of transcription (STAT)1-dependent genes. Extracellular-signal-regulated kinase (ERK)1/2 pathway is also involved in the protection of keratinocytes from the proinflammatory effect of IFN-gamma. Here we show that, after IFN-gamma stimulation, SOCS1 inhibited IFN-gamma receptor and STAT1 phosphorylation but maintained ERK1/2 activation. SOCS1 was also necessary for the IFN-gamma-induced RAS and Raf-1 activities in keratinocytes. The enhanced ERK1/2 pathway in SOCS1-overexpressing keratinocytes was in part responsible for their inability to respond to IFN-gamma, in terms of CXCL10 and CCL2 production, and for the high production of CXCL8. Moreover, SOCS1 interacted with the RAS inhibitor p120 RasGAP and promoted its degradation after IFN-gamma stimulation. We hypothesize that SOCS1 functions as suppressor of IFN-gamma signaling, not only by inhibiting STAT1 activation but also by sustaining ERK1/2-dependent antiinflammatory pathways.

  • Immunology and Microbiology

DAMGO-induced expression of chemokines and chemokine receptors: the role of TGF-beta1.

In Journal of Leukocyte Biology on 1 April 2008 by Happel, C., Steele, A. D., et al.

Studies from a number of laboratories suggest that modulation of cytokine expression plays an integral role in the immunomodulatory activity of opioids. Previously, our laboratory reported that activation of the mu-opioid receptor induced the expression of CCL2, CCL5, and CXCL10, as well as CCR5 and CXCR4. Previous work has also suggested the possibility that TGF-beta may participate in the opioid-induced regulation of immune competence, and in the present study, we set out to determine the role of this cytokine in the control of chemokine and chemokine receptor expression. We found that D-ala(2),N-Me-Phe(4)-Gly-ol(5)enkephalin (DAMGO), a highly selective mu-opioid agonist, induced the expression of TGF-beta1 expression at the protein and mRNA levels. In turn, the addition of TGF-beta1 was found to induce CCL5 and CXCR4 expression but not CCL2, CXCL10, or CCR5. Further analysis showed that pretreatment with neutralizing anti-TGF-beta1 blocked the ability of DAMGO to induce CCL5 or CXCR4. Similarly, pretreatment with cycloheximide prevented CCL5 or CXCR4 mRNA expression, consistent with the observation that DAMGO induction of chemokine and chemokine receptor expression requires newly synthesized TGF-beta1 protein. These results describe a common molecular basis for the activation of chemokine and chemokine receptor expression and may permit the development of strategies to inhibit certain undesirable immunological properties of micro-opioid agonists such as morphine and heroin.

  • Immunology and Microbiology

Paired synovial tissue samples were obtained from both clinically uninvolved (CU) and clinically involved (CI) knee joints of eight rheumatoid arthritis (RA) patients. In addition, biopsies were taken from five control subjects. We observed the expression of the chemokines CXCL8, CXCL9, CXCL10, CCL2 and CCL4 in CI and CU joints of RA patients. In particular, CXCL8 protein levels were specifically increased in CI joints compared with CU joints, which was confirmed by immunohistochemistry and in situ hybridization.

  • Immunology and Microbiology
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