Insulin release from cultured B-cells

Established RlNm5F and lN111 R1 and newly available HlT-T15 and UMR 407/3 B-cell lines have been successfully maintained in vitro. With the exclusion of UMR 407/3 cells, all lines were continuously propagable. Doubling times and plating efficiencies for HlT-T15, RlNm5F, lN111 R1 and UMR 407/3 cells were 20 hours and 85%, 31 hours and 76%, 24 hours and 80% and 38 hours and 94% respectively. All the cell lines were anchorage dependent, but only UMR 407/3 cells grew to confluence. Only HlT-T15 and UMR 407/3 cells produced a true insulin response to glucose but glucose markedly increased the rate of D-[U14C]glucose oxidation by all the cell lines. Glucose induced insulin release from HlT-T15 cells was biphasic with an exaggerated first phase. Insulin release from HlT-T15, RlNm5F and IN111 R1 cells was stimulated by amino acids and sulphonylureas. Glucagon stimulated insulin release from HlT-T15 and RlNm5F cells while somatostatin and pancreatic polypeptide inhibited release. These observations suggest that net insulin release from the whole islet may be the result of significant paracrine interaction. HlT-T15 and RlNm5F cell insulin release was stimulated by forskolin and inhibited by imidazole. Ca2+ channel blockade and calmodulin inhibition suppressed insulin release from HlT-T15, RlNm5F and IN111 R1 cells. In addition phorbol esters stimulated insulin release from RlNm5F cells. These data implicate cAMP, Ca2+ and protein kinase-C in the regulation of insulin release from cultured B-cells. Acetylcholine increased insulin release from HlT-T15 and RlNm5F cells. Inhibition of the response by atropine confirmed the involvement of muscarinic receptors. HlT-T15 cell insulin release was also inhibited by adrenaline. These observations suggest a possible role for the autonomic nervous system in the modulation of insulin release. Preliminary studies with a human insulinoma maintained in monolayer culture have demonstrated a limited life span of some seven weeks, a continuous low level of insulin release but no insulin response to glucose challenge.

Is there a role for telemedicine in adult allergy services?

Telemedicine refers to the application of telecommunication and information technology (IT) in the delivery of health and clinical care at a distance or remotely and can be broadly considered in two modalities: store-and-forward and real-time interactive services. Preliminary studies have shown promising results in radiology, dermatology, intensive care, diabetes, rheumatology and primary care. However, the evidence is limited and hampered by small sample sizes, paucity of randomised controlled studies and lack of data relating to cost-effectiveness, health related quality of life and patient and clinician satisfaction. This review appraises the evidence from studies that have employed telemedicine tools in other disciplines and makes suggestions for its potential applications in specific clinical scenarios in adult allergy services. Possible examples include: triaging patients to determine the need for allergy tests; pre-assessment for specialised treatments such as allergen immunotherapy; follow up to assess treatment response and side effects; and education in self-management plan including training updates for self-injectable adrenaline and nasal spray use. This approach might improve access for those with limited mobility or living far away from regional centres, as well as bringing convenience and cost savings for the patient and service provider. These potential benefits need to be carefully weighed against evidence of service safety and quality. Keys to success include delineation of appropriate clinical scenarios, patient selection, training, IT support and robust information governance framework. Well-designed prospective studies are needed to evaluate its role. This article is protected by copyright. All rights reserved.