Apoptosis and pathogenesis of avian influenza A (H5N1) virus in humans.
The pathogenesis of avian influenza A (H5N1) virus in humans has not been clearly elucidated. Apoptosis may also play an important role. We studied autopsy specimens from 2 patients who died of infection with this virus. Apoptosis was observed in alveolar epithelial cells, which is the major target cell type for the viral replication. Numerous apoptotic leukocytes were observed in the lung of a patient who died on day 6 of illness. Our data suggest that apoptosis may play a major role in the pathogenesis of influenza (H5N1) virus in humans by destroying alveolar epithelial cells. This pathogenesis causes pneumonia and destroys leukocytes, leading to leukopenia, which is a prominent clinical feature of influenza (H5N1) virus in humans. Whether observed apoptotic cells were a direct result of the viral replication or a consequence of an overactivation of the immune system requires further studies.
Uiprasertkul
Mongkol
M
Department of Microbiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Kitphati
Rungrueng
R
Puthavathana
Pilaipan
P
Kriwong
Romchat
R
Kongchanagul
Alita
A
Ungchusak
Kumnuan
K
Angkasekwinai
Suwimon
S
Chokephaibulkit
Kulkanya
K
Srisook
Kanittar
K
Vanprapar
Nirun
N
Auewarakul
Prasert
P
D017209:Apoptosis; D001344:Autopsy; D006801:Humans; D053124:Influenza A Virus, H5N1 Subtype / Q000472:pathogenicity*; D007251:Influenza, Human / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011650:Pulmonary Alveoli / Q000473:pathology / Q000821:virology; D012367:RNA, Viral / Q000032:analysis; D020545:Respiratory Mucosa / Q000473:pathology / Q000821:virology; D013785:Thailand
D012367:RNA, Viral