Wasp sting-associated cold urticaria.
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Biomedical subjects
Publications and source records attributed to C Hauser.
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The orphan receptor ARP-1/COUP-TFII, a member of the chicken ovalbumin upstream promoter transcription factor (COUP-TF) subfamily of nuclear receptors, strongly represses transcriptional activity of numerous genes, including several apolipoprotein-encoding genes. Recently it has been demonstrated that the mechanism by which COUP-TFs reduce transcriptional activity involves active repression and transrepression. To map the domains of ARP-1/COUP-TFII required for repressor activity, a detailed deletion analysis of the protein was performed. Chimeric proteins in which various segments of the ARP-1/COUP-TFII carboxy terminus were fused to the GAL4 DNA binding domain were used to characterize its active repression domain. The smallest segment confering active repressor activity to a heterologous DNA binding domain was found to comprise residues 210 to 414. This domain encompasses the region of ARP-1/COUP-TFII corresponding to helices 3 to 12 in the recently published crystal structure of other members of the nuclear receptor superfamily. It includes the AF-2 AD core domain formed by helix 12 but not the hinge region, which is essential for interaction with a corepressor in the case of the thyroid hormone and retinoic acid receptor. Attachment of the nuclear localization signal from the simian virus 40 large T antigen (Flu tag) to the amino terminus of ARP-1/COUP-TFII abolished its ability to bind to DNA without affecting its repressor activity. By using a series of Flu-tagged mutants, the domains required for transrepressor activity of the protein were mapped. They include the DNA binding domain and the segment spanning residues 193 to 399. Transcriptional activity induced by liver-enriched transactivators such as hepatocyte nuclear factor 3 (HNF-3), C/EBP, or HNF-4 was repressed by ARP-1/COUP-TFII independent of the presence of its cognate binding site, while basal transcription or transcriptional activity induced by ATF or Sp1 was not perturbed by the protein. In conclusion, our results demonstrate that the domains of ARP-1/COUP-TFII required for active repression and transrepression do not coincide. Moreover, they strongly suggest that transrepression is the predominant mechanism underlying repressor activity of ARP-1/COUP-TFII. This mechanism most likely involves interaction of the protein with one or several transcriptional coactivator proteins which are employed by various liver-enriched transactivators but not by ubiquitous factors such as Sp1 or ATF.
The presence and regulation of pituitary adenylate cyclase activating peptide (PACAP) was investigated in the adult rat superior cervical ganglion. Double-labelling immunofluorescence using specific antibodies against PACAP and vasoactive intestinal peptide (VIP) revealed a dense innervation of postganglionic sympathetic neurones by PACAP-immunoreactive but VIP-negative nerve endings that mainly were of preganglionic origin since they disappeared after transection of the cervical sympathetic trunk. Since PACAP regulates transmitter synthesis and release in sympathetic neurones in vitro, this finding provides a morphological correlate for modulatory effects of PACAP in vivo. Few neurones contained PACAP under normal conditions. However, the number of PACAP-positive neurones increased in response to axotomy of the postganglionic nerves. Many of the newly PACAP-positive neurones also contained VIP, suggesting that both peptides are regulated by similar mechanisms.
BACKGROUND: As the cutaneous lymphocyte-associated antigen appears to detect circulating T cells that migrate to the skin in atopic dermatitis but not T cells that migrate to mucosal sites in allergic asthma and rhinitis, we investigated T-cell activation markers and CD30 on the cutaneous lymphocyte-associated antigen-positive circulating T-cell subset in atopic dermatitis to see whether these markers are different from those in normal controls and related to disease activity. DESIGN: Open study. SETTING: University referral center. PATIENTS: Twelve patients with atopic dermatitis and 12 healthy controls. INTERVENTION: Combined UV-A and UV-B treatment for 2 months. MAIN OUTCOMES MEASURES: Percentage of circulating cutaneous lymphocyte-associated antigen-positive T cells that express HLA-DR, interleukin-2 receptor, CD69, CD71, and CD30 (triple-color flow cytometric analysis). Clinical score, Dermatology Life Quality Index, pruritus score, and consumption of topical corticosteroids were determined. RESULTS: Increased relative numbers of cutaneous lymphocyte-associated antigen-positive T cells expressing HLA-DR, interleukin-2 receptor, and CD30 were found in patients with atopic dermatitis before treatment. Treatment with UV-A and UV-B was associated with clinical improvement and a decrease of levels of HLA-DR, interleukin-2 receptor, and CD30 in cutaneous lymphocyte-associated antigen-positive T cells. HLA-DR on cutaneous lymphocyte-associated antigen-positive T cells correlated significantly with the clinical score. CONCLUSION: Expression of HLA-DR and interleukin-2 receptor is a sensitive marker of disease activity in atopic dermatitis. Apart from giving information on disease activity in atopic dermatitis, the availability of skin-seeking T cells in the blood offers the opportunity to obtain further information on T cells that may have effector function in the skin.
Two chemotactic cytokines, monocyte chemoattractant protein-1 (MCP-1) and RANTES, possibly contribute to the recruitment and activation of leukocytes in inflamed tissues. The expression of these cytokine genes was evaluated in tissue sections from resected bowel segments of 14 patients with inflammatory bowel disease (IBD) and seven control patients by use of 35S-labelled antisense RNA probes. MCP-1 and RANTES transcripts were generally increased in the intestinal mucosa of patients with IBD, compared with controls. Whereas MCP-1 gene expression in the mucosa was restricted to the lamina propria, the gene coding for RANTES was expressed in intraepithelial lymphocytes and in the subepithelial lamina propria. Furthermore, MCP-1 mRNA, but not RANTES mRNA, was abundant in vessel-associated cells, such as endothelial cells, medial smooth muscle cells, and intraluminal cells; in smooth muscle cells of the intestinal tunica muscularis; and in cells of the myenteric plexus. Compared with controls, a significant increase of MCP-1-expressing cells was observed in tissue specimens from patients with IBD, in endothelial cells of venules, and in cells present in the lumen of intestinal vessels. Conversely, the expression of MCP-1 mRNA in smooth muscle cells and myenteric plexus cells appeared to be comparable in control and diseased intestines. The increased number of MCP-1 and RANTES mRNA-expressing cells in mucosa from patients with IBD suggests that these cytokines play a role in the pathogenesis of mucosal inflammation. Furthermore, the expression of the MCP-1 gene in vessel-associated cells may indicate its involvement in mechanisms regulating the adhesion of blood monocytes to endothelial cells.
We studied the involvement of chemokines that bind to G protein-coupled receptors in the migration of skin homing T cells across a bilayer vascular construct (BVC) consisting of a fibroblast matrix underneath an activated endothelial (EC) monolayer. Based on the expression of the cutaneous lymphocyte-associated antigen (CLA), a skin homing receptor, CD45R0+ T cells freshly isolated from blood or HUT-78 cutaneous T lymphoma cells were separated into CLA+ and CLA- subpopulations. These T cells were incubated on interleukin (IL)-1 beta and tumor necrosis factor-alpha-activated EC, and the number of transmigrated cells was determined. The chemokine IL-8 was selectively involved in the enhanced migration of CLA+ T cells across activated EC as demonstrated by blocking antibody to IL-8 but not to GRO-alpha, MCP-1 and RANTES. Identical results were obtained with both human umbilical vein EC (HUVEC) and microvascular skin EC (HDMEC). Pertussis toxin selectively inhibited the enhanced transendothelial migration (TEM) of CLA+ T cells, suggesting that CLA-dependent TEM depends on Gi protein-transmitted signals. Moreover, the IL-8 receptor B (IL-8RB) appeared to be functionally involved in TEM, as demonstrated by receptor desensitization with the CXC chemokines IL-8 and GRO-alpha and by blocking the IL-8RB with specific monoclonal antibodies. Although only the IL-8RB was involved in CLA-dependent TEM, mRNA encoding IL-8RA and IL-8RB was expressed by both CLA+ and CLA- T cells. This correlated with IL-8RA and IL-8RB surface expression on these cells. Thus, the IL-8RB is selectively functional in TEM of T cells expressing the skin homing receptor CLA. Our results demonstrate a critical role for IL-8 and possibly other IL-8RB ligands in addition to the IL-8RB in TEM and suggest the involvement of these molecules in the homing of specific T cells to inflamed skin.
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A case of contact urticaria associated with a serous rhinitis, dyspnea, wheezing, and a dry cough appearing after the application of a hair conditioner on the scalp is reported. Prick test results with the conditioner diluted at 1/16 and 1/8 were strongly positive (+3), as well as a prick test (+3) with one component of the conditioner called "hydrolyzed proteins," which contained hydrolyzed bovine collagen and stearyl trimethylammonium chloride.
It was recently reported that cAMP upregulated IL-4 in T cell lines generated in vitro and expressing an unrestricted lymphokine pattern. In order to study the effect of cAMP on IL-4 released by freshly isolated T cell populations, we tested various T cell subsets that have previously been reported to synthesize this lymphokine. We found that cAMP upregulated IL-4 release from in vivo activated single CD4+ peripheral T cells and CD4+CD8-HSAlowNK1.1- thymocytes stimulated with ionomycin and phorbol ester. Furthermore, as in conventional single CD4+ or CD8+ thymocytes, cAMP enhanced IL-4 production in CD4+CD8-NK1.1+ thymocytes. This latter subset has recently been shown to belong to a independent T cell lineage that is positively selected by MHC class I molecules, recognizes CD1 and expresses a restricted T cell receptor repertoire. In contrast, cAMP appeared not to upregulate IL-4 in a third independent T cell lineage. This was suggested by the observation that cAMP did not increase IL-4 in CD3+CD4-CD8- thymocytes, which are thought not to give rise to conventional single CD4+ or CD8+ T cells. It therefore appears that cAMP is coupled differently to IL-4, depending on the T cell lineage. In contrast, in all IL-4 producing stages of conventional T cells, IL-4 is consistently upregulated by cAMP.
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The receptor erbB2/neu is a member of the epidermal growth factor receptor (EGFR or erbB) family that also includes erbB3 and erbB4. Amplification of the erbB2/neu gene is found in many cancer types and its overexpression is correlated with a poor prognosis for breast and ovarian cancer patients. Investigation of the biology of erbB2 led to the identification of a family of ligands termed neuregulins which included the neu-differentiation factors, the heregulins, a ligand with acetylcholine-receptor-inducing activity and glial growth factor. Several lines of evidence suggest that heterodimerization of erbB2 with other erbB receptors is required for neuregulin signalling. Here we investigate the developmental role of erbB2 in mammalian development in mice carrying an erbB2 null allele. We find that mutant embryos die before E11, probably as a result of dysfunctions associated with a lack of cardiac trabeculae. Development of cranial neural-crest-derived sensory ganglia was markedly affected. DiI retrograde tracing revealed that the development of motor nerves was also compromised. Our results demonstrate the importance of erbB2 in neural and cardiac development.
The cutaneous lymphocyte-associated antigen (CLA) is the major T cell ligand for the vascular adhesion molecule E-selectin, and it has been proposed to be involved in the selective targeting of memory T cells reactive with skin-associated Ag to cutaneous inflammatory sites. To further investigate the relation of CLA and cutaneous T cell responses, we analyzed the CLA phenotype of circulating memory T cells in patients with allergic contact dermatitis and atopic dermatitis (AD) alone vs in patients manifesting bronchopulmonary atopy (asthma with or without AD) and nonallergic individuals. Significant T cell proliferative responses to Ni, a contact allergen, and to the house dust mite (HDM), an allergen to which sensitization is often observed in AD and/or asthma, was noted only in allergic and atopic individuals, respectively. When the minor circulating CLA+CD3+CD45RO+ subset was separated from the major CLA-CD3+CD45RO+ subpopulation in Ni-sensitive subjects, the Ni-dependent memory T cell response was largely confined to the CLA+ subset. A similar restriction of the T cell proliferative response to the CLA+ memory subset was observed for HDM in patients with AD alone. In HDM-sensitive patients with asthma with or without AD, however, the CLA- subset exhibited a strong antigen-dependent proliferation, in contrast to patients with AD alone, whose CLA- subset proliferated very weakly to HDM. In asthma with or without AD, the HDM-dependent proliferation slightly predominated in the CLA- when compared to the CLA+ subset. The functional linkage between CLA expression and disease-associated T cell effector function in AD was also demonstrated by the finding that the circulating CLA+ T cell subset in AD patients, but not nonatopic controls, selectively showed both evidence of prior activation (human histocompatibility antigen-DR expression) and spontaneous production of interleukin 4 but not interferon-gamma. Taken together, these observations demonstrate the correlation of CLA expression on circulating memory T cells and disease-associated memory T cell responses in cutaneous hypersensitivity, and they suggest the existence of mechanisms capable of sorting particular T cell Ag specificities and lymphokine patterns into homing receptor-defined memory subsets.
The cutaneous lymphocyte-associated Ag (CLA) is expressed by a subset of circulating memory/effector T cells and by the vast majority of skin-infiltrating T cells. CLA is thought to target skin-associated T cells to inflammatory skin sites by interacting with endothelial cell ligand E-selectin (CD62E). We have examined adhesion molecules involved in the migration of human CLA+ and CLA- memory/effector T lymphocytes through IL-1- and TNF-alpha-activated and nonactivated HUVEC layers under static (nonflow) conditions. CLA-enriched memory/effector T lymphocytes migrated more actively across cytokine-activated HUVEC than CLA-depleted memory/effector T cells. This enhanced migration is dependent on the CLA/E-selectin interaction. mAb to very late Ag-4 (VLA-4) and vascular cell adhesion molecule-1 (VCAM-1) blocked the migration of CLA-enriched, but not of CLA-depleted, T cells across activated HUVEC. The observation that anti-VLA-4 and anti-CLA mAb did not show additional inhibition supports the concept that CLA and VLA-4 are sequentially involved in the extravasation. The fact that only CLA+ T cells were inhibited by the anti-VLA-4 mAb suggests that, in this system, CLA engagement is required for using the VLA-4/VCAM-1 pathway. Our studies demonstrate that CLA+ T cells use LFA-1/intercellular leukocyte adhesion molecule-1 (ICAM-1) for transmigration but that CLA expression is not required for the LFA-1/ICAM-1-dependent transmigration because anti-CD18/CD11a mAbs and anti-ICAM-1 mAbs were able to block T cell migration regardless of the activation state of HUVEC or the CLA expression by T cells. Taken together, our results suggest that CLA has a homing function in conducting the T cell to interact with LFA-1/ICAM-1 and/or VLA-4/VCAM-1; this results in enhanced adhesion and migration across cytokine-activated endothelial cells.
Intravenous administration of trinitrophenyl-modified isologous immunoglobulin-induced nonresponsiveness to subsequent epicutaneous painting of sensitizing doses of trinitrochlorobenzene. Isologous immunoglobulin with various degrees of trinitrophenyl substitution (11.2, 14.3, 27 and 47.3) prevented sensitization. The suppression of contact hypersensitivity was dependent on the dose of tolerogen and was hapten specific. Tolerance was inducible in mice of the strains CBA (H-2k), C57BL/6 (H-2b), and DBA/2 (H-2d) but not in Balb/C (H-2d) mice, suggesting that this trait maps outside the murine major histocompatibility complex. Tolerance induced by trinitrophenyl-modified immunoglobulin was associated with decreased hapten-induced proliferation of draining lymph-node cells. Unlike in other models of tolerance in which a decreased interleukin-2 to interleukin-4 ratio can be observed, administration of tolerizing trinitrophenylated immunoglobulin was associated with deficient hapten-induced release of both interleukin-2 and interleukin-4.
The cutaneous lymphocyte-associated antigen (CLA) is a carbohydrate epitope present on memory/effector T cells that infiltrate inflamed skin. E-selectin is the ligand for CLA and is induced under inflammation on endothelial cells. CLA was originally postulated as a phenotype marker for skin-associated T cells. We studied the specific in vitro response to skin-associated allergens of CLA+ and CLA-CD45RO+ T cells in atopic dermatitis (AD) and contact dermatitis (CD), which represent two well-characterized T cell-mediated cutaneous allergic inflammations. Whereas CLA+ T cells from AD patients preferentially responded to house dust mite (HDM) and CLA+ T cells from nickel CD patients showed an increased response to nickel, CLA-T cells showed very little response in both cases. In contrast, tetanus toxoid, a systemically acting antigen, induced a proliferative response in both CLA+ and CLA- cells. Interestingly the response to HDM in patients with asthma +/- AD was preferentially found in the CLA- subset indicating the involvement of different homing receptors for mucosal tissues. Moreover, CLA+ T cells showed enhanced migration through activated human umbilical vein endothelial cell monolayers compared to CLA- T cells. The CLA binding to E-selectin is initially responsible for the extravasation that also involves VLA-4/VCAM-1 and LFA-1/ICAM-1 interactions. We have recently identified IL-8 as an endothelial cell-derived chemokine and the IL-8 receptor type B which control CLA+ T cell migration. Such a CLA-mediated migration would localize memory/effector T cells that respond to antigens and reach the body through inflamed skin. Our data support the existence of a regionalization of the immune system and in particular of the skin immune system. It may allow an efficient distribution of the immune defense to different sites of the body.