A comparison of spontaneous and CSF added CFU-MG colony formation in healthy, sick and hypotrophic pre-term infants.

Myelopoietic progenitor cells (CFU-MG) have been studied from peripheral blood of healthy, sick, and hypotrophic pre-term infants. Methylcellulose cultures were prepared simultaneously with and without exogenous colony stimulating factor. It was found that large numbers of circulating CFU-M are present at birth in healthy infants, smaller numbers in sick infants, and very few in hypotrophic infants. Exogenous CSF increases the number of colonies in cultures of healthy infants at birth. A limiting factor in spontaneous colony formation is the production of CSF by the cells in culture. This is particularly evident in sick infants. During the postnatal course similar levels of circulating CFUc, higher than in adult blood, are found in all three groups of pre-term infants.