Destruction of human microvascular endothelial cell capillary-like microtubules by Brazilian purpuric fever-associated Haemophilus influenzae biogroup aegyptius.
When grown in the presence of Matrigel, monolayers of an immortalized human microvascular cell line (HMEC-1) form capillary-like microtubule networks. Previous work, using HMEC-1 monolayers, demonstrated a significant difference in in vitro cytotoxicity between Brazilian purpuric fever (BPF)-associated Haemophilus influenzae biogroup aegyptius (HAE) strains and non-BPF-associated HAE strains. The present study demonstrates that BPF-related cytotoxic differences can also be observed in HMEC-1 microtubule networks. At a multiplicity of infection (MOI) of 2 x 10(-2) bacteria/tissue culture cell, BPF-associated strain F3031 disrupted the microtubule network, producing random clumps of rounded cells at 48 h of incubation. Infection with non-BPF-associated strain F1947 at the same MOI produced no observable microtubule disruption. The ability of HMEC-1 microtubule model to differentiate virulent and avirulent HAE in vitro will further aid in the study of BPF pathogenesis. In addition, the fact that the HMEC-1 cells can be induced to form microtubules make it an excellent model system for the general study of many of the agents of vascular purpura.
Quinn
F D
FD
Emerging Bacterial and Mycotic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Ga 30333.
Weyant
R S
RS
Candal
F J
FJ
Ades
E W
EW
D001427:Bacterial Toxins / Q000633:toxicity*; D016923:Cell Death; D002460:Cell Line; D003094:Collagen; D004338:Drug Combinations; D004730:Endothelium, Vascular / Q000382:microbiology / Q000648:ultrastructure*; D006192:Haemophilus Infections / Q000382:microbiology; D006193:Haemophilus influenzae / Q000302:isolation & purification / Q000472:pathogenicity*; D006801:Humans; D007797:Laminin; D008870:Microtubules / Q000187:drug effects / Q000382:microbiology / Q000648:ultrastructure*; D011509:Proteoglycans; D011693:Purpura / Q000382:microbiology; D014774:Virulence
D001427:Bacterial Toxins; D004338:Drug Combinations; D007797:Laminin; D011509:Proteoglycans; C059485:matrigel; D003094:Collagen