Glutaminolysis is required in maintaining immune regulatory functions in B cells

IL-10-expressing regulatory B cells (B10 cells) are dysfunctional in patients with many immune disorders. The underlying mechanism remains to be further elucidated. Glutamine is an essential nutrient for cell metabolism. This study aims to elucidate the role of glutaminolysis in maintaining the immune regulatory capacity in B10 cells. Peripheral blood samples were collected from 50 patients with allergic rhinitis and 50 healthy control subjects. B cells were isolated from blood samples by cell sorting with flow cytometry. The role of glutaminolysis in regulating B10 cell activities was assessed by immunological and biochemical approaches. The results showed that B cells from patients with allergic rhinitis expressed low levels of the transporter of glutamine and neutral amino acid. Glutaminolysis was required in the IL-10 expression in B cells. The glutamine catabolism was required in B10 cell generation. The mTOR activation mediated the glutaminolysis-associated B10 cell induction, and the suppression of the B cell glycogen synthase kinase-3 (GSK3) activation. GSK3 activation suppressed IL-10 expression in B cells. Inhibition of GSK3 enhanced IL-10 expression in B cells and alleviated experimental allergic rhinitis by generating immune competent type 1 regulatory T cells.

Interaction between Ras and Bcl2L12 in B cells suppresses IL-10 expression

The pathogenesis of recurrent tonsillitis is to be further investigated. B cell-derived interleukin (IL)-10 plays a critical role in immune regulation. Ras activation plays an important role in cancer and many immune disorders. This study aims to investigate the role of Ras activation in down regulating IL-10 expression in tonsillar B cells. Surgically removed tonsil tissues were collected from patients with recurrent acute tonsillar inflammation; B cells were isolated from the tonsillar tissues by flow cytometry sorting to be analyzed by the Ras-specific enzyme-linked immunosorbent assay and pertinent immunological approaches. We found that, compared to peripheral B cells (pBC), B cells isolated from the tonsillar tissues with recurrent inflammation (tBC) showed higher Ras activation, lower IL-10 expression and higher Bcl2L12 expression. Bcl2L12 formed a complex with GAP (GTPase activating protein) to prevent Ras from deactivating. The Ras activation triggered the MAPK/Sp1 pathway to promote the Bcl2L12 expression in B cells. Bcl2L12 prevented the IL-10 expression in tBCs, that was counteracted by inhibition of Ras or the Ras signal transduction pathway. In conclusion, Bcl2L12 interacts with Ras activation to compromise immune tolerance in the tonsils by inhibiting the IL-10 expression in tBCs. Inhibition of Bcl2L12 can restore the IL-10 expression in tBCs.

A20-OVA Nanoparticles Inhibit Allergic Asthma in a Murine Model

The skewed T helper (Th) 2 response plays a critical role in the pathogenesis of allergic asthma. Regulatory T (Treg) cells and the regulatory cytokines are required in maintaining the homeostasis in the body. This study aims to determine the effects of a poly(lactic-co-glycolic) acid (PLGA)-ovalbumin (OVA)+A20 (a ubiquitin E3 ligase) nanovaccine on inhibiting allergic asthma in a murine model. In this study, A20 and OVA (a model antigen) were encapsulated into PLGA to be a nanovaccine (PLGA-OVA+A20). An allergic asthma murine model was developed with OVA as the specific antigen to test the role of PLGA-OVA+A20 nanovaccine in maintaining the immune homeostasis in the airway tissues. The results showed that PLGA-OVA+A20 nanovaccine inhibited the asthma responses in mice by suppressing Th2 inflammatory responses, promoting the generation of Treg cells in the airway tissues. We conclude that the PLGA-OVA+A20 nanovaccine has a marked inhibitory effect on the airway allergic response in sensitized mice by significantly promoting the generation of Treg cell and IL-10. The data suggest that PLGA-OVA+A20 has translational potential in the treatment of allergic asthma.

Feasibility of a remote monitoring system for home-based non-invasive positive pressure ventilation of children and infants

OBJECTIVE

We examined the safety, efficacy, and caregiver satisfaction of a remote monitoring system for home-based non-invasive positive pressure ventilation of children and infants with upper airway obstruction.

METHODS

Fourteen pediatric patients (age 50 days to 12 years) treated in our ENT unit from March 2009 to July 2011 and requiring home-based non-invasive positive pressure ventilation were enrolled in this feasibility study; one patient underwent CPAP and the other 13 patients underwent Bi-PAP. User satisfaction with the monitoring system was assessed by questionnaires given at regular intervals to parents and attending physicians. Compliance was determined by the number of days that parents uploaded data to the central server. In addition, the feasibility of the system was analyzed by comparing costs and time expenditures with traditional clinic visits.

RESULTS

The patients' parents (primary caregivers) uploaded data via the system on 93.3% of trial days, indicating good compliance. No system or device failures occurred. Both parents and physicians considered the system convenient and ease to use according to >80% of the returned questionnaires, indicating high user satisfaction. The mean distance between the patients' homes and the hospital was 113 ± 71 km, and parents required 371 ± 182 min to reach the hospital for a follow-up visit. In contrast, it took only 5.7 ± 3.1 min per day to transmit data (P<0.05 compared to hospital travel time). As of August 2011, average cost per patient was 632 Chinese yuan (¥), which was ¥924 (59.4%) lower than the cost of clinic visits (¥1556).

CONCLUSIONS

The remote monitoring system was safe, reliable, easy to use, cost effective, and widely acceptable to both parents and physicians. This system may allow for safe and effective home-based non-invasive positive pressure ventilation for children with upper airway obstructions in developing countries with limited health care budgets or for patients from remote regions.