Molecular characterization of the intact mouse muscle spindle using a multi-omics approach.

The proprioceptive system is essential for the control of coordinated movement, posture, and skeletal integrity. The sense of proprioception is produced in the brain using peripheral sensory input from receptors such as the muscle spindle, which detects changes in the length of skeletal muscles. Despite its importance, the molecular composition of the muscle spindle is largely unknown. In this study, we generated comprehensive transcriptomic and proteomic datasets of the entire muscle spindle isolated from the murine deep masseter muscle. We then associated differentially expressed genes with the various tissues composing the spindle using bioinformatic analysis. Immunostaining verified these predictions, thus establishing new markers for the different spindle tissues. Utilizing these markers, we identified the differentiation stages the spindle capsule cells undergo during development. Together, these findings provide comprehensive molecular characterization of the intact spindle as well as new tools to study its development and function in health and disease.

Transneuronal Dpr12/DIP-δ interactions facilitate compartmentalized dopaminergic innervation of Drosophila mushroom body axons.

The mechanisms controlling wiring of neuronal networks are not completely understood. The stereotypic architecture of the Drosophila mushroom body (MB) offers a unique system to study circuit assembly. The adult medial MB γ-lobe is comprised of a long bundle of axons that wire with specific modulatory and output neurons in a tiled manner, defining five distinct zones. We found that the immunoglobulin superfamily protein Dpr12 is cell-autonomously required in γ-neurons for their developmental regrowth into the distal γ4/5 zones, where both Dpr12 and its interacting protein, DIP-δ, are enriched. DIP-δ functions in a subset of dopaminergic neurons that wire with γ-neurons within the γ4/5 zone. During metamorphosis, these dopaminergic projections arrive to the γ4/5 zone prior to γ-axons, suggesting that γ-axons extend through a prepatterned region. Thus, Dpr12/DIP-δ transneuronal interaction is required for γ4/5 zone formation. Our study sheds light onto molecular and cellular mechanisms underlying circuit formation within subcellular resolution.

Beta-glycoglycosphingolipid-induced augmentation of the anti-HBV immune response is associated with altered CD8 and NKT lymphocyte distribution: a novel adjuvant for HBV vaccination.

BACKGROUND: Non-responsiveness towards the currently used hepatitis B virus (HBV) vaccine is a major problem in attempts to protect against HBV infection. Several methods have been tested to overcome the lack of an effective immune response towards HBV antigens. Adjuvants that augment the immunologic reaction are essential components of the vaccines. Beta-glycosphingolipids exert a natural killer T cell (NKT)-mediated immunomodulatory effect in various disorders. AIMS: The aim of the present study was to test the ability of these compounds to augment the immune response towards HBV antigens, making them potential adjuvants for HBV vaccines. Six groups of mice were injected with different formulations of an HBV vaccine, along with various doses of beta-glucosylceramide (beta-GC), beta-lactosylceramide (beta-LC), or a combination of both (IGL) in different doses. The effect of beta-glycosphingolipids on the immune response towards HBV was tested by fluorescence-activated cell sorting analysis of hepatic and splenic NKT and CD8 lymphocytes, and serum cytokine levels. RESULTS: Beta-sphingolipid treatment altered the hepatic NKT and CD8 lymphocyte distribution. beta-LC, beta-GC, and the combination of both augmented anti-HBV immunity, increasing both the anti-HBs titers and the percentage of mice exhibiting high titers. This effect was associated with altered hepatic NKT and CD8+ lymphocyte distribution. CONCLUSIONS: In summary, beta-glycosphingolipids increased the anti-HBV immune response in association with an altered NKT and CD8 lymphocyte distribution, making beta-glycosphingolipids potential potent adjuvants for overcoming non-responsiveness to HBV vaccination and augmenting the anti-viral immune response.

Acute hepatitis A infection in pregnancy is associated with high rates of gestational complications and preterm labor.

BACKGROUND & AIMS: Hepatitis A virus (HAV) infection is the most common cause of acute hepatitis but is rarely reported during pregnancy. Our aim was to evaluate the impact of acute HAV infection on pregnancy outcome. METHODS: Consecutive admissions of 79,458 pregnant females during a 25-year period were retrospectively reviewed. RESULTS: Thirteen cases of second and third trimester HAV infection were found and evaluated. Nine of the 13 patients (69%) developed gestational complications, including premature contractions (n = 4), placental separation (n = 2), premature rupture of membranes (n = 2), and vaginal bleeding (n = 1). In 8 of these patients, complications led to preterm labor, at a median of 34 gestational weeks (range, 31-37 weeks). Delivery was vaginal in 12 of the 13 cases; fetal distress was noted in a single case, and meconium in amniotic fluid in 2 cases. Median birth weight was 1778 grams and 3040 grams in preterm and term deliveries, respectively (P < .05). Child outcome was favorable in all cases. In 4 cases, neonatal serum HAV RNA levels were measured and found negative. The presence of fever and hypoalbuminemia were associated with delivery at an earlier gestational week. There was a positive relation between gestational week at diagnosis of HAV infection and birth week (r = 0.68, P = .02), suggesting a causality relationship. All mothers featured full recovery from HAV infection. CONCLUSIONS: Acute HAV infection during pregnancy is associated with high risk of maternal complications and preterm labor. HAV serology and maternal vaccination during prepregnancy evaluation should be considered in areas of the world in which susceptible adult populations exist.