The invention is based on the discovery that interleukin-1 alpha (IL-1 alpha) is expressed on the proinflammatory CD 14+CD 16+ monocyte subset. Importantly, since IL-1 alpha appears to be almost exclusively expressed on this monocyte subset and not other leukocytes, it represents an ideal marker for targeting the CD 14+CD 16+ monocyte subset. The effectiveness of an agent that depletes such pathogenic cells or modulates IL-1 alpha function on such cells type can be monitored by assessing CD 14+CD 16+ monocyte levels or functionality.
