INVESTIGADORES
GAMBERALE Romina
congresos y reuniones científicas
Título:
1. NK cells in CLL: defective expression of CD62L and IFNg production.
Autor/es:
ZANETTI SAMANTA ROMINA; MORANDE PABLO; BORGE MERCEDES; NANNINI PAULA ROMINA; GAMBERALE ROMINA; ZWIERNER NORBERTO; GIORDANO MIRTA
Lugar:
caba
Reunión:
Congreso; 1° French-Argentine Immunology Congress,; 2010
Resumen:
Patients with CLL exhibit a
progressive deficiency in the immune response which has been associated to
autoimmune disorders, recurrent infections and second malignancies. Given the
key role of NK cells in immunesurveillance, we have evaluated the expression of
CD62L and CCR7, two molecules involved in NK migration to secondary lymphoid
tissues in CD56+CD3- cells from CLL patients and healthy age-matched donors. By
flow cytometric analysis we observed a lower proportion of CD62L+ cells in
peripheral blood NK cells from CLL patients (30.4 ± 1.6) compared to healthy
donors 44.8 ± 2.6 (results are expressed as the mean ± SD, n= 28 and 45
respectively, p<0.01). In regard to NK cells expressing CCR7, we found a
comparable low proportion of positive cells in both groups (6.8 ± 3.4 versus 19.2
± 6.9, healthy donors vs CLL patients, n= 11 and 12 respectively, not
significant), except for three CLL patients who had more than 40% of
CD56+CD3-CCR7+ cells. We also analyzed the functional activity of NK cells from
CLL patients by evaluating their capacity to produce IFN when activated with
Poly I:C, a TLR-3 specific agonist. To this aim, we incubated peripheral blood
mononuclear cells for 24 h in the presence of poly I:C (50 ug/ml) and
determined the proportion of NK that produced IFN by flow cytometry. There was
no difference in spontaneous IFN production between NK cells from healthy
donors and CLL patients (% CD56+CD3-INF+ cells 1.8 ± 0.3 vs 1.7 ± 0.4, n=17
and 19 respectively). By contrast, NK cells from CLL patients showed an
impaired response to poly I:C stimulation (% CD56+CD3-INF+ cells 17.0 ± 2.8 vs
9.5 ± 2.5, p<0.01). In conclusion, our findings indicate that NK cells from
CLL patients present phenotypic and functional defects that may be implicated
in the high incidence of second malignancies in this pathology.