0000000000628595
AUTHOR
K Reske
Potassium-inhibited processing of IL-1 beta in human monocytes.
Agents that deplete cells of K+ without grossly disrupting the plasma membrane were found to stimulate the cleavage of pro-interleukin (IL)-1 beta to mature IL-1 beta. Agents examined in this study included staphylococcal alpha-toxin and gramicidin, both of which selectively permeabilize plasma membranes for monovalent ions, the ionophores nigericin and valinomycin, and the Na+/K+ ATPase inhibitor ouabain. K+ depletion by brief hypotonic shock also triggered processing of pro-IL-1 beta. The central role of K+ depletion for inducing IL-1 beta maturation was demonstrated in cells permeabilized with alpha-toxin: processing of pro-IL-1 beta was totally blocked when cells were suspended in mediu…
Non-coordinate synthesis of MHC class II proteins and invariant chains by epidermal Langerhans cells derived from short-term in vitro culture
Epidermal cells (EC) prepared from Lewis rat skin contained 2-3% class II+, LCA+ Langerhans cells (LC). LC enriched from freshly isolated EC suspensions proved highly effective accessory cells when presenting the nominal antigen OVA to an RT1.Bl-restricted ovalbumin (OVA)-specific rat T cell clone. Short-term preculture of the EC resulted in diminished OVA presenting capacity of the LC. Flow cytometry (FCM) analysis of class II and gamma chain expression revealed an up-regulation of class II on the LC's cell surface, consistent with earlier findings in mouse and human. However, while the presence of gamma chains in mouse LC was reported to decline to negligible levels during culture we obse…