Macrophage Activation… The Missing Link to Activation an immune response to Melanoma..Jim Breitfeller

"The development of Th1 cells producing high levels of IFN-gamma could not be induced with dendritic cells alone but required the addition of appropriately activated macrophages." Et al A. O'Gara March 23, 1993 "Dendritic cells and macrophages are required for Th1 development of CD4+ T cells from αβ TCR transgenic mice: IL-12 substitution f.or macrophages to stimulate IFN-γ production is IFN-γ-dependent"
Local IL-12 therapy stimulates Th cells to secrete Th1 cytokines. Exogenous IL-12 application creates an environment rich in IL-12 around the cancer site. In such a local environment, newly activated Th cells, responding to the presence of cancer, exit the blood and are influenced to become Th1 cells and secrete more Th1 cytokines and activate macrophages and NK cells. Activated macrophages will produce more IL-12 and via positive feedback, cell-mediated immunity can be promoted to battle the cancer thereby leading to the prevention of reoccurrence. As you can see, the activated macrophage secretes IL-12, IL-1a, IL-1b, and IL-6 along with a Chemoattractant, IP-10. Without macrophage activation, the immune response does not take place and the patient will relapse.(see graphic below)

With IL-1b and IL-6 missing, the T-Regulatory Cells (Tregs) rule the Tumor's Microenviroment. IL-6 controls Th17 immunity by inhibiting the conversion of naive CD4+ T cells into Foxp3+ regulatory T cells. IL-1β–Mediated Signals Preferentially Drive Conversion of Regulatory T Cells but Not Conventional T Cells into IL-17–Producing Cells (Danger Signal).So if the IL-1b signaling is missing,conversion of the Tregs never take place along with no Danger Signals.

Dr. Steven Rosenberg is using engineered T-cells that secrete IL-12 to stimulate Th cells to secrete Th1 cytokines. This sets in motion the positive feed back loop needed to initiate an immune response. His therapy is show great promise. “It is not the strongest of the species that survives, nor the most intelligent, but the one most responsive to change.” ~Charles Darwin~ Take Care, Jimmy B