Swiprosin-1 Expression Is Up-Regulated through Protein Kinase C-theta and NF-kappaB Pathway in T Cells

Swiprosin-1 exhibits the highest expression in CD8+ T cells and immature B cells and has been proposed to play a role in lymphocyte biology through actin remodeling. However, regulation of swiprosin-1 gene expression is poorly understood. Here we report that swiprosin-1 is up-regulated in T cells by PKC pathway. Targeted inhibition of the specific protein kinase C (PKC) isotypes by siRNA revealed that PKC-theta is involved in the expression of swiprosin-1 in the human T cells. In contrast, down-regulation of swiprosin-1 by A23187 or ionomycin suggests that calcium-signaling plays a negative role. Interestingly, swiprosin-1 expression is only reduced by treatment with NF-kappaB inhibitors but not by NF-AT inhibitor, suggesting that the NF-kappaB pathway is critical for regulation of swiprosin-1 expression. Collectively, these results suggest that swiprosin-1 is a PKC-theta-inducible gene and that it may modulate the late phase of T cell activation after antigen challenge.

Cervical Vestibular-Evoked Myogenic Potentials Using Vibration and Sound in Normal Subjects / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The aim of this study was to investigate and compare the incidence and the characteristics of parameters of cervical vestibular-evoked myogenic potentials (cVEMPs) using air-conducted (AC) and bone-conducted (BC) stimulations in normal subjects. SUBJECTS AND METHOD: Twenty-four normal subjects (48 ears) with normal hearing and no previous history of dizziness were included. cVEMP responses were recorded by surface electrodes on sternocleidomastiod muscles in response to AC and BC stimuli sequentially. Variances of parameters, including thresholds, amplitudes and interaural amplitude difference ratios (IADR), were analyzed and compared. RESULTS: cVEMP responses were clearly observed in all 48 ears in both AC and BC cVEMP tests. There was no significant difference in latencies (p1 and n1). However, the thresholds in BC cVEMP testing were significantly lower than those in AC cVEMP testing, when compared to the maximum stimulation level. Interaural amplitude difference ratios showed no significant difference in between the two tests, although amplitudes at maximum stimulation intensity in BC cVEMP testing were significantly larger than those in AC cVEMP testing. CONCLUSION: This study shows that BC cVEMP testing shows lower thresholds compared to AC cVEMP testing in normal subjects, suggesting that the threshold value can be used as a parameter in detecting vestibular dysfunction in the clinic. Further studies in patients with various vestibular disorders are needed.