| Abstract: | When blood monocytes from sheep are grown upon glass in 100% autologous plasma they divide with low mitotic indices, but if the plasma is taken from the sheep three or four days after the implantation of a small Teflon or stainless steel cylinder, the maximum mitotic indices of the monocytes cultured in that plasma rise. Plasma collected from the sheep in the first two days after operation is often toxic to cultured autologous monocytes. An equivalent sham operation increases the mitogenicity of the plasma, but without a preceding toxic period. No consistent effects upon the numbers of circulating blood monocytes were noted following implantation operations. A hypothesis is presented which suggests that blood monocyte multiplication in vivo and in vitro is dependent upon (a) a lesion which causes cell attachment, and (b) a humoral component of the plasma which stimulates mitosis. Surgery, and the implantation of foreign materials will increase the concentration of such a substance in plasma. |
