Immunoglobulin signal transduction guides the specificity of B cell-T cell interactions and is blocked in tolerant self-reactive B cells.

The specificity of antibody (Ab) responses depends on focusing helper T (Th) lymphocyte signals to suitable B lymphocytes capable of binding foreign antigens (Ags), and away from nonspecific or self-reactive B cells. To investigate the molecular mechanisms that prevent the activation of self-reactive B lymphocytes, the activation requirements of B cells specific for the Ag hen egg lysozyme (HEL) obtained from immunoglobulin (Ig)-transgenic mice were compared with those of functionally tolerant B cells isolated from Ig-transgenic mice which also express soluble HEL. To eliminate the need for surface (s)Ig-mediated Ag uptake and presentation and allow the effects of sIg signaling to be studied in isolation, we assessed the ability of allogeneic T cells from bm12 strain mice to provide in vivo help to C57BL/6 strain-transgenic B cells. Interestingly, non-tolerant Ig-transgenic B cells required both allogeneic Th cells and binding of soluble HEL for efficient activation and Ab production. By contrast, tolerant self-reactive B cells from Ig/HEL double transgenic mice responded poorly to the same combination of allogeneic T cells and soluble HEL. The tolerant B cells were nevertheless normally responsive to stimulation with interleukin 4 and anti-CD40 Abs in vitro, suggesting that they retained the capacity to respond to mediators of T cell help. However, the tolerant B cells exhibited a proximal block in the sIg signaling pathway which prevented activation of receptor-associated tyrosine kinases in response to the binding of soluble HEL. The functional significance of this sIg signaling defect was confirmed by using a more potent membrane-bound form of HEL capable of triggering sIg signaling in tolerant B cells, which markedly restored their ability to collaborate with allogeneic Th cells and produce Ab. These findings indicate that Ag-specific B cells require two signals for mounting a T cell-dependent Ab response and identify regulation of sIg signaling as a mechanism for controlling self-reactive B cells

An investigation of completion times on the Screener and Opioid Assessment for Patients with Pain - revised (SOAPP-R)

BACKGROUND: Respondents' scores to the Screener and Opioid Assessment for Patients with Pain - revised (SOAPP-R) have been shown to be predictive of aberrant drug-related behavior (ADB). However, research is lacking on whether an individual's completion time (the amount of time that he/she takes to finish the screener) has utility in predicting ADB, despite the fact that response speed has been useful in predicting behavior in other fields. The purpose of this study was to evaluate the degree to which SOAPP-R completion time is predictive of ADB.MATERIALS AND METHODS: This retrospective study analyzed completion-time data from 82 adult emergency department patients who completed the SOAPP-R on a tablet computer. The utility of SOAPP-R completion times in predicting ADB was assessed via logistic regression and the area under the curve (AUC) statistic. An external measure of ADB using Prescription Drug Monitoring Program data defined ADB to have occurred in individuals with at least four opioid prescriptions and at least four prescribers in 12 months. RESULTS: Although there was a slight trend for individuals with greater completion times to have greater odds of ADB (odds ratio 1.004 in simple logistic regression), the association between SOAPP-R completion time and ADB was not statistically significant in either simple logistic regression (P=0.307) or multiple logistic regression adjusting for SOAPP-R score (P=0.419). AUC values for the prediction of ADB using completion time alone, SOAPP-R score alone, and both completion time and SOAPP-R score were 0.63, 0.64, and 0.65, respectively. CONCLUSION: There was no significant evidence that SOAPP-R completion times were predictive of ADB among emergency department patients. However, the AUC value for completion times was only slightly less than that for SOAPP-R total scores

A protective role for IL-13 receptor α 1 in bleomycin-induced pulmonary injury and repair.

Molecular mechanisms that regulate lung repair vs. progressive scarring in pulmonary fibrosis remain elusive. Interleukin (IL)-4 and IL-13 are pro-fibrotic cytokines that share common receptor chains including IL-13 receptor (R) α1 and are key pharmacological targets in fibrotic diseases. However, the roles of IL-13Rα1 in mediating lung injury/repair are unclear. We report dysregulated levels of IL-13 receptors in the lungs of bleomycin-treated mice and to some extent in idiopathic pulmonary fibrosis patients. Transcriptional profiling demonstrated an epithelial cell-associated gene signature that was homeostatically dependent on IL-13Rα1 expression. IL-13Rα1 regulated a striking array of genes in the lung following bleomycin administration and Il13ra1 deficiency resulted in exacerbated bleomycin-induced disease. Increased pathology in bleomycin-treated Il13ra1(-/-) mice was due to IL-13Rα1 expression in structural and hematopoietic cells but not due to increased responsiveness to IL-17, IL-4, IL-13, increased IL-13Rα2 or type 1 IL-4R signaling. These data highlight underappreciated protective roles for IL-13Rα1 in lung injury and homeostasis