Open AccessHaemopoietic stem cells: spleen colony‐forming cells are normally actively proliferating
Author(s) -
Nečas E.,
Znojil V.,
Šefc L.
Publication year - 1990
Publication title -
cell proliferation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.647
H-Index - 74
eISSN - 1365-2184
pISSN - 0960-7722
DOI - 10.1111/j.1365-2184.1990.tb01351.x
Subject(s) - spleen , bone marrow , stem cell , biology , cyclophosphamide , dna synthesis , immunology , lipopolysaccharide , haematopoiesis , microbiology and biotechnology , dna , chemotherapy , biochemistry , genetics
. The haemopoietic stem cells forming spleen colonies (CFU‐S) had on average 30 to 40% of cells engaged in the DNA synthesis in normal mice continuously over 4 years. A majority of experiments aimed at the suppression of the CFU‐S proliferation, which included suppression of the T‐lymphocytes by means of cyclosporin A or by adult thymectomy, administration of antibacterial and antifungal agents and maintainance of mice in a sterile environment, suppression of antibody‐producing cells by a successive administration of the bacterial lipopolysaccharide and cyclophosphamide and attempts to increase the total number of CFU‐S in the body through massive transfusions of bone marrow cells or by grafting plugs of the bone marrow under the kidney capsulae, have not been sufficiently effective. A transient suppression of CFU‐S proliferation occurred during recovery of the haemopoietic tissue from damage caused by cyclophosphamide. The results support the view that changes in CFU‐S numbers and in the proportion of them in DNA synthesis may be positively correlated when CFU‐S numbers fluctuate physiologically about their normal values. The failure to manipulate the CFU‐S proliferation rate easily suggests that proliferation of these cells may not be under a strong ‘switch on ‐ switch off’ control.