Scanning electron micrograph of Hodgkin's cells taken from the pleural effusions of a 55 year old, male patient with mixed cellularity Hodgkin's disease". The cells are grown in tissue culture. Hodgkin's disease is a cancer of the lymphoreticular system - the mediator of non- specific cell defence mechanisms & the immune response. The various cell lines of the system are all subject to cancerous changes. In Hodgkin's disease, the nature of the cell line is unknown, but in the most common form the cell population is mixed. Magnification: x1,000 at 8x10 inch size."