3 research outputs found
A study of lymphocyte functions in multiple myelopma
Multiple myeloma (MM) is a lymphoproliferative disorder which is
characterized by an accumulation of clonotypic plasma, cells in the bone
marrow leading to an overproduction of monoclonal immunoglobulin (mIg).
The disease often implies a poor prognosis. lg-reactive T-cells in MM
have been described previously and lg- and dendritic cell (DC)-based
immunotherapies in order to elicit and-rumour activity have been
attempted in MM. DCs are efficient antigen presenting cells and important
in both innate and adaptive immunity. The present study aimed at
investigating lymphocyte functions underlying immune mechanisms
associated with MM.
In the first part of the study we show that mature monocyte-derived DCS
from MM patients are susceptible to autologous natural killer (NK,) cell
lysis. When NK cells were activated with lower concentrations of IL-2, NK
cell-mediated lysis was significantly higher as compared with NK lysis
from controls, thus suggesting that DCs in MM patients may be prone to
recognition and eradication by NK cells. The second part of the study
focuses on specific T-cell immunity in MM. DCs loaded with mIg was
cocultured with autologous T-cells and the proliferation was monitored
over time. The results show a proliferation of CD4+ T-cells in response
to mIg-loaded antigen presenting cells, which could be for most cases
inhibited with anti-DR blocking antibody, indicating a MHC class
II-restricted response. The cytokine pattern showed negative or low
levels of INF-gamma production and varying and enhanced levels of IL4,
IL-6 and/or IL10, which suggests a lack of T helper (Th) type 1
activation and a tendency to a Th2 polarization. These observations point
to immunoregulatory mechanisms in MM which may be of importance for
iminunotherapies