Studies on colony-stimulating factor (CSF): role of the kidney in clearing serum CSF

Corticosteroids and granulopoiesis: effects upon in vitro colony formation

6 alpha Methylprednisolone (MP) and prednisone treatment of mice and man causes reduced in vitro colony formation in soft agar in the presence of added colony stimulating activity (CSA). MP or prednisone administration sharply reduces the amount of CSA released from white blood cell feeder layers and the CSA released into the serum of mice given endotoxin. The reduction in colony formation by the marrow of MP treated subjects is explained by the diminished endogenous CSA elaboration by CSA producing cells over the seven day assay period; the colony forming cells (CFC) are capable of responding to increased added CSA. There is no evidence for diminished in vivo granulopoiesis following MP treatment; hence in vitro colony formation is not a valid corollary of in vivo granulopoiesis in the presence of high dose corticosteroid treatment.

Stimulation of human haemopoietic cells by colony stimulating factors: adherent cell dependent colony stimulating activity in human serum

The number of granulocyte-macrophage clones formed in agar culture of bone marrow is dependent on levels of colony stimulating activity (CSA) a proposed in vivo haemopoietic regulator. A dose-response relationship for stimulation of human haemopoietic cells by CSA is demonstrated, which could be explained by thresholds of stimulation to cell division following a normal distribution. A simple method for the comparison of activities of test and control sources of CSA is presented. The apparent potentiating effect of the addition of two sources of CSA is explained by this dose-response relationhip. Haemopoietic cells from patients with chronic granulocytic or acute myeloid leukaemia showed the same dose-response relationship. CSA levels in normal human sera were greatly reduced by assay in the absence of adequate numbers of bone marrow "adherent cells" (cells adherent to nylon or plastic) or peripheral blood leucocytes, suggesting the presence of two kinds of CSA in human serum, one dependent on the presence of bone marrow adherent cells and one effective in their absence. Reduction of numbers of nonspecific esterase positive cells in the bone marrow sample correlated with reduction in the stimulating effect of serum. In all sera tested, adherent cell dependent CSA was the major component.

Alteration of colony-stimulating factor output, endotoxemia, and granulopoiesis in cyclic neutropenia

Cellular and humoral factors involved in the regulation of granulopoiesis were evaluated in two patients with cyclic neutropenia by utilizing the agar-gel marrow culture technique to serially study marrow granulocytic colony-forming capacity (CFC) and the urinary output of colony-stimulating factor (CSF). CSF output varied inversely with peripheral neutrophil counts and directly with monocyte counts and evidence for infection (endotoxemia and/or staphylococcal abscesses). Following autologous infusion of one patient's plasma obtained during a period of neutropenia, increased urinary excretion of CSF occurred concomitant with increments in both marrow CFC and the proportion of granulocytic progenitor cells in DNA synthesis. Neutrophil periodicity was not altered by the administration of the neutropenic plasma. These findings are consistent with the hypothesis that cyclic neutropenia is caused by a quantitatively decreased entry of stem cells or granulocytic progenitor cells into granulopoiesis.

Inhibition of cell proliferation in renal failure and its significance to the uraemic syndrome: a review

The effect of acute and chronic renal failure on cell proliferation in rapidly dividing tissues has been examined in man and animal models. The evidence reviewed supports the hypothesis that renal failure results in a general inhibition of cell proliferation. Cell population kinetic studies of gastrointestinal and skin epithelia in experimental acute renal failure show a prolongation of the cell generation cycle. Less detailed investigations of other proliferative cell systems indicate an inhibitory effect on proliferation within the generative compartment of the erythroid series, lymphoid tissue, seminiferous epithelia and wound granulation tissue. This inhibition appears partly responsible for anaemia and impaired wound healing and may contribute to the abnormal immune responses, gastrointestinal tract lesions and male sterility found in renal failure.