Cytokine production by peripheral blood monocytes and T cells during haemopoietic recovery after intensive chemotherapy

Summary We studied the production of cytokines by peripheral blood monocytes and T cells during the period of haematological recovery following intensive chemotherapy. Twelve adults with haematological malignancies received consolidation chemotherapy of complete remission. Monocytes and T cells were collected during the phase of recovery from intensive chemotherapy, and were incubated for 24 h in a culture medium with 10% FCS. Concentrations of cytokines in the culture supernatant were measured with an enzymelinked immunosorbent assay. During the recovery phase, concentrations of IL‐6, G‐CSF and IL‐1β in the culture supernatant of the collected monocytes significantly exceeded those of the monocytes obtained from normal healthy subjects. Similarly, the concentrations of GM‐CSF and IFN‐γ in the supernatant of recovery phase T cells significantly exceeded those of normal T cells. Plasma levels of these cytokines were also elevated. These data suggest that the monocytes and T cells may be activated in vivo to produce haemopoietic cytolines during haematological recovery, and that, during haematological recovery, the monocytes and T cells may be actively involved in the induction of haematopoiesis following the myelosuppression induced by chemotherapy.