Abstract
A method is described in which washed whole cells of Corynebacterium parvum were chemically and enzymatically extracted to remove cytoplasm and cell-wall lipids. The resultant insoluble cell-wall residue possessed lympho-reticular stimulating properties as measured by their ability to increase spleen weight and protect against tumour-cell challenge. Analysis of the final product by chromatography and infrared spectroscopy has shown it to consist of carbohydrate and peptidoglycan, both of which appear to be necessary for the activities measured.