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Tsan, Min-Fu, and Baochong Gao. Cytokine function of heat shock proteins. Am J Physiol Cell Physiol 286: C739-C744, 2004; 10.1152/ajpcell.00364.2003.-Extensive work in the last 10 years has suggested that heat shock proteins (HSPs) may be potent activators of the innate immune system. It has been reported that Hsp60, Hsp70, Hsp90, and gp96 are capable of inducing the production of proinflammatory cytokines by the monocyte-macrophage system and the activation and maturation of dendritic cells (antigen-presenting cells) in a manner similar to the effects of lipopolysaccharide (LPS) and bacterial lipoprotein, e.g., via CD14/ Toll-like receptor2 (TLR2) and CD14/TLR4 receptor complex-mediated signal transduction pathways. However, recent evidence suggests that the reported cytokine effects of HSPs may be due to the contaminating LPS and LPS-associated molecules. The reasons for previous failure to recognize the contaminant(s) as being responsible for the reported HSP cytokine effects include failure to use highly purified, low-LPS preparations of HSPs; failure to recognize the heat sensitivity of LPS; and failure to consider contaminant(s) other than LPS. Thus it is essential that efforts should be directed to conclusively determine whether the reported HSP cytokine effects are due to HSPs or to contaminant(s) present in the HSP preparations before further exploring the implication and therapeutic potential of the putative cytokine function of HSPs. tumor necrosis factor-[alpha]; lipopolysaccharide; macrophages; innate immune system

Tumor necrosis factor-[alpha] (TNF-[alpha]), one of the major inflammatory cytokines, is known to influence endothelial cell migration. In this study, we demonstrate that exposure of calf pulmonary artery endothelial cells to TNF-[alpha] caused an increase in the formation of membrane protrusions and cell migration. Fluorescence microscopy revealed an increase in [[alpha].sub.v][[beta].sub.3] focal contacts but a decrease in [[alpha].sub.5][[beta].sub.1] focal contacts in TNF-[alpha]-treated cells. In addition, both cell-surface and total cellular expression of [[alpha].sub.v][[beta].sub.3]-integrins increased significantly, whereas the expression of [[alpha].sub.5][[beta].sub.1]-integrins was unaltered. Only focal contacts containing [[alpha].sub.v][[beta].sub.3]- but not [[alpha].sub.5][[beta].sub.1]-integrins were present in membrane protrusions of cells at the migration front. In contrast, robust focal contacts containing [[alpha].sub.5][[beta].sub.1]-integrins were present in cells behind the migration front. A blocking antibody to [[alpha].sub.v][[beta].sub.3], but not a blocking antibody to [[alpha].sub.5]-integrins, significantly inhibited TNF-[alpha]-induced cell migration. These results indicate that in response to TNF-[alpha], endothelial cells may increase the activation and ligation of [[alpha].sub.v][[beta].sub.3] while decreasing the activation and ligation of [[alpha].sub.5][[beta].sub.1]-integrins to facilitate cell migration, a process essential for vascular wound healing and angiogenesis. integrins; focal contacts; tumor necrosis factor-[alpha]

A study was conducted on the induction of manganese superoxide dismutase (SOD) in human monocytes without inflammatory cytokine production by a mutant Escherichia coli endotoxin. It was demonstrated that the endotoxin retained its full capacity to coagulate Limulus amoebocyte lysate compared with the wild-type E. coli endotoxin. However, it failed to induce production of tumor necrosis factor-alpha and macrophage inflammatory protein-1-alpha by monocytes and did not induce phosphorylation and nuclear translocation of protein kinase.

The tracheal insufflation of naked recombinant plasmids containing chloramphenicol acetyltransferase, a bacterial gene, resulted indirect in vivo transfection of the lungs. When the simian virus 40 (SV40) promoter/enhancer is used, there is no detectable transfection. Insufflation of plasmid DNA is as efficient as plasmid-liposome complexes in transfecting the lungs, but intravenous injection of plasmid alone or plasmid-liposome complexes is not successful.Thus intratracheal delivery of recombinant plasmid DNA has a potential implication for lung-specific gene therapy.

Increase in pulmonary Mn superoxide dismustase (SOD) mRNA by tumor necrosis factor (TNF) or interleukin-1 (IL-1) depends on the path of administration. Intratracheal (IT) insufflation of TNF or IL-1 preferentially increases the pulmonary levels while IV infusion has no effect on the lung, spleen or kidney. IT insufflation of IL-1 accelerates the rate of Mn SOD mRNA and is controlled at the transcriptional level.

Significant extension of the survival of rats exposed to 100% O2 and amelioration of O2-induced pulmonary injury resulted from endotoxin at a dosage of 5 micrograms. A preferential increase in pulmonary manganese superoxide dismutase (MnSoD) was related to endotoxin-induced O2 tolerance. Analysis of MnSoD and alveolar macrophages confirmed that tracheal insufflation of endotoxin provided protection from oxygen toxicity.

PAI-1 mRNA was injected in isolated rat lung fibroblasts and kidney epithelial cells by in vitro exposure to high oxygen partial pressure. High oxygen partial pressure was also applied to the pulmonary tissue of hyperoxic stressed rats. These experiments were conducted to determine whether cells from lungs were vulnerable to hyperoxia-initiated PAI-1 upregulation and also if hyperoxia-induced elevations in PAI-1 expression revealed in vitro also occurred in vivo. p52(PAI-1) mRNA levels were increased in cultured rat cells from kidneys and lung fibroblasts.

This study explores the effects of oxytocin receptor (OXTR) in the trigeminal ganglion (TG) on orofacial neuropathic pain. We demonstrate that OXTR activation in the TG relieves the orofacial ectopic pain as well as inhibits the upregulated expression of calcitonin gene-related peptide (CGRP), IL-1β, and TNFα in the TG and spinal trigeminal nucleus caudalis (SpVc) of rats with inferior alveolar nerve transection. OXTR, a G protein-coupled receptor, has been demonstrated to play a significant role in analgesia after activation by its canonical agonist oxytocin (OXT) in the dorsal root ganglion. However, the role of OXTR in the trigeminal nervous system on the orofacial neuropathic pain is still little known. In the present study, we aimed to investigate the regulation effect and mechanism of OXTR in the TG) and SpVc) on orofacial ectopic pain induced by trigeminal nerve injury. The inferior alveolar nerve (IAN) was transected to establish a ectopic pain model. A behavioral test with electronic von Frey filament demonstrated IAN transection (IANX) evoked mechanical hypersensitivity in the whisker pad from day 1 to at least day 14 after surgery. In addition, administration of OXT (50 and 100 μM) into the TG attenuated the mechanical hypersensitivity induced by IANX, which was reversed by pretreatment with L-368,899 (a selective antagonist of OXTR) into the TG. In addition, immunofluorescence showed the expression of OXTR in neurons in the TG and SpVc. Furthermore, Western blot analysis indicated that the upregulated expression of OXTR, CGRP, IL-1β, and TNFα in the TG and SpVc after IANX was inhibited by the administration of OXT into the TG. And the inhibition effect of OXT on the expression of CGRP, IL-1β, and TNFα was abolished by preapplication of OXTR antagonist L-368,899 into the TG. [ABSTRACT FROM AUTHOR]

Endotoxin (LPS) is a potent inducer of tumor necrosis factor-[Alpha] (TNF-[Alpha]) and manganese superoxide dismutase (MnSOD). Recent evidence suggests that LPS induction of TNF-[Alpha] and MnSOD mRNAs is mediated through distinct intracellular signal transduction pathways. Membrane CD14 (mCD14) and Toll-like receptor-4 (TLR4) mediate LPS induction of TNF-[Alpha] in macrophages. In the current study, we evaluated the role of mCD14 and TLR4 in LPS induction of MnSOD using peritoneal macrophages from CD14 knockout (CD14-KO) mice and mice with the Tlr4 gene point mutation (C3H/HeJ) or deletion (C57BL/10ScCr). We studied mCD14-dependent (1 and 10 ng/ml) and mCD14-independent (1,000 ng/ml) concentrations of LPS. Compared with control (BALB/c) macrophages, LPS at 1 and 10 ng/ml failed to induce TNF-[Alpha] or MnSOD mRNA in CD14-KO macrophages. However, LPS at 1,000 ng/ml induced TNF-[Alpha] and MnSOD mRNAs equally in macrophages from CD14-KO and control mice. LPS (1, 10, or 1,000 ng/ml) failed to induce TNF-[Alpha] or MnSOD mRNA and failed to activate nuclear factor-KB in C3H/HeJ or C57BL/ 10ScCr macrophages. Measurements of TNF-[Alpha] and MnSOD enzyme activity paralleled TNF-[Alpha] and MnSOD mRNA levels. These data demonstrate that, like TNF-[Alpha], induction of MnSOD by LPS is mediated by mCD14 and TLR4 in murine macrophages. tumor necrosis factor-[Alpha]; manganese superoxide dismutase; endotoxin resistance; nuclear factor-[Kappa] B; peritoneal macrophage

Extensive work in the last 10 years has suggested that heat shock proteins (HSPs) may be potent activators of the innate immune system. It has been reported that Hsp60, Hsp70, Hsp90, and gp96 are capable of inducing the production of proinflammatory cytokines by the monocyte-macrophage system and the activation and maturation of dendritic cells (antigen-presenting cells) in a manner similar to the effects of lipopolysaccharide (LPS) and bacterial lipoprotein, e.g., via CD14/ Toll-like receptor2 (TLR2) and CD14/TLR4 receptor complex-mediated signal transduction pathways. However, recent evidence suggests that the reported cytokine effects of HSPs may be due to the contaminating LPS and LPS-associated molecules. The reasons for previous failure to recognize the contaminant(s) as being responsible for the reported HSP cytokine effects include failure to use highly purified, low-LPS preparations of HSPs; failure to recognize the heat sensitivity of LPS; and failure to consider contaminant(s) other than LPS. Thus it is essential that efforts should be directed to conclusively determine whether the reported HSP cytokine effects are due to HSPs or to contaminant(s) present in the HSP preparations before further exploring the implication and therapeutic potential of the putative cytokine function of HSPs. [ABSTRACT FROM AUTHOR]

Examines the role of α[sub v]Β[sub 3]-integrin in tumor necrosis factor-α-induced endothelial cell migration. Formation of membrane protrusions and cell migration; Integrity of endothelium and repairing during angiogenesis; Regulation on the balance between adhesion and mitigation to changing environment in the blood stream.

Studies the role of membrane CD14 and Toll-like receptor-4 in the induction of tumor necrosis factor (TNF)-alpha and manganese superoxide dismutase (MnSOD) by endotoxin. Role of mCD14 in lipolysaccharide (LPS) induction of TNF-alpha and MnSOD; Effect of Tlr4 gene point mutation on LPS induction of TNF-alpha.