immunology of infectious and parasitic diseases - XXXVII Congress ...

MATURATION AND ACTIVATION OF MURINE DENDRITIC CELLS stimulated
with CELL WALL COMPONENTS OF Paracoccidioides brasiliensis
YASMIN SOARES DE LIMA¹; ANA CAMILA OLIVEIRA SOUZA¹; RAFFAEL JUNIO
ARAÚJO DE CASTRO¹ ALDO HENRIQUE P. TAVARES², ANAMÉLIA L. BOCCA¹
1 Department of Cell Biology, University of Brasília, Brasília, Brazil; ²Ceilândia
College, University of Brasília, Brasília, Brazil.
Introduction: The cell wall of Paracoccidioides brasiliensis contains several
components capable to modulate the immune response of the host. The fungi cell
wall can be fractionated into two principal cell wall fractions: one composed mainly by
beta-1,3-glucan (F1) and another composed basically of alpha-1,3-glucan (F2). Beta-
1,3-glucan can recruit inflammatory cells, stimulate cytokine production and
granulomatous reaction. Alpha-1,3-glucan is in major related to the virulence of the
yeasts cells. The interaction between the immune cells and cell wall fractions can
induce different patterns of response. In this study, our objective was to evaluate the
influence of the cell wall fractions during in vitro dendritic cells maturation. Methods
and Results: Bone marrow cells of C57/bl6 mice were collected from femur and tibia
and differentiated into dendritic cells in the presence of GM-CSF. After 8 days of
differentiation, the cells were incubated for 24 hours with F1 and F2 fractions at
different concentrations. The expression of MHCII, CD83, DCSIGN and CD11c were
evaluated by FACS. The F1 fraction induced an increase in the CD11c - DCSIGN - and
MHCII + CD11c - cells, besides a decrease in the MHCII + CD11c + cells. The F2 fraction
in low concentrations increases the MHCII + CD11c + , MHCII + CD11c - , DCSIGN - CD11 - ,
CD83 + CD11c - and CD83 - CD11c - cells. Conclusion: By the proportion of
MHCII + CD11c + cells, these results indicate that F1 fraction inhibits the maturation of
dendritic cells, while F2 fraction probably induces an early maturation and a larger
capacity to present antigens.
Financial support: CNPq, FAPDF and CAPES.