Identification of Receptors and Signaling Changes Involved in the Activation of U937, Mono-Mac-6 and THP-1 Cell Lines After Treating with Heat Shock Protein 70 (Hsp70), CD23 and CD36
Abstract
Abstract
Cluster of differentiation 23 (CD23) and 36 (CD36) are important cell surface proteins related to phagocytosis expressed on a variety of differentiated cell types especially monocytes/macrophages. Thus, they are critical in cell-cell signaling and communication between cells and their outside environments. The present laboratory study evaluated the effect of chemical modifiers (HSP70 heat — shock protein 70, malondialdehyde—MDA, HSP70-MDA) on the expression of the CD23 and CD36 receptors in the monocytic cell lines (U937, Mono-Mac-6 and THP-1) by measuring their FL1-CD23 and CD36 by flow cytometer. This was evaluated along with their effects on size and granularity of the monocytic cell by measuring their forward scatter (FSC) and side scatter (SSC), respectively by flow cytometer. Treatment with MDA, an oxidative stress maker, resulted in the activation of CD23 but not CD36. Treatment with other modifiers did not significantly activate CD23 and none activated CD36. In the monocytic cells, the forward scatter (FSC), which correlates to cell size was higher in untreated, followed by HSP70-treated, MDA-treated and lastly HSP70-MDA-treated cells. In general, the granularity of untreated cells (side scatter; SSC) was higher than treated monocytic cells indicating that the populations of modifier-treated monocytes/macrophages were made up of smaller agranular cells, while that of untreated cells was made up of larger agranular cells. There seems be a cross-talk between CD23 and CD36 cells, since activation of CD23 results in suppression of CD36 cells. Future studies should focus on elucidating further the seemingly cross-talk between CD23 and CD36 following treatment with a variety of modifier molecules