Ultrastructural studies on dengue virus type 2 infection of cultured human monocytes.
BACKGROUND
Early interaction of dengue virus and monocyte/macrophages could be an important feature for virus dissemination after its initial entry via the mosquito vector. Since ultrastructural analysis of this interaction has not been reported, dengue type 2 (DEN2) virus-infected human monocyte cultures were studied at 1, 2, 4 and 6 hours after infection.


RESULTS
Typical dengue particles and fuzzy coated viral particles were 35 to 42 nm and 74 to 85 nm respectively. Viruses were engulfed by phagocytosis and macropicnocytosis leading to huge vacuoles and phagosomes inside the monocytes. Interaction of monocytes with DEN2 virus induced apoptosis, characterized by nuclear condensation and fragmentation, cellular shrinkage, blebbing and budding phenomena and phagocytosis of apoptotic cells by neighboring monocytes. This finding was confirmed by TUNEL. Ultrastructural features associated to DEN2 virus replication were not observed.


CONCLUSIONS
These data suggest that clearance of the virus by monocytes and cellular death are the main features during the initial interaction of DEN2 virus and monocytes and this could be important in the rapid elimination of the virus after infection by mosquito vector.
Mosquera
Jesus A
JA
Seccion de Inmunologia y Biologia Celular, Instituto de Investigaciones Clinicas Dr, Americo Negrette, Facultad de Medicina, Universidad del Zulia, Maracaibo, Venezuela. mosquera99ve@yahoo.com
Hernandez
Juan Pablo
JP
Valero
Nereida
N
Espina
Luz Marina
LM
Añez
German J
GJ
D017209:Apoptosis; D003716:Dengue Virus / Q000378:metabolism*; D006801:Humans; D009000:Monocytes / Q000648:ultrastructure* / Q000821:virology*; D010587:Phagocytosis