Insulin oscillation oscillations. The insulin oscillations are generated by pulsatile release of the hormone from the pancreas. Insulin originates from beta cells located in the islets of Langerhans. Since each islet contains up to 2000 beta cells and there are one million islets in the pancreas it is apparent that pulsatile secretion requires sophisticated synchronization both within and among the islets of Langerhans. Pulsatile insulin secretion from individual beta cells is driven by oscillation of the calcium concentration in the cells. In beta cells lacking contact, the periodicity of these oscillations is rather variable (2-10 min). However, within an islet of Langerhans
Langerhans cell key mechanism by which HPV evades immune detection "in vivo". Specifically, HPV16 entry into Langerhans cells via the annexin A2/S100A10 heterotetramer results in suppressive signaling and lack of Langerhans cell-mediated immune responses. This Langerhans cell-targeted immune escape mechanism seems to be conserved among different HPV genotypes enabling these viruses to remain undetected in the absence of other inflammatory events. T cells exposed to these inactivated Langerhans cells are not anergic, and can be activated against HPV upon receiving the appropriate stimuli at a later time point. It was demonstrated that Langerhans cells in HPV-induced cervical lesions were spherical, lacked dendrites,