Bartonella quintana variably expressed outer membrane proteins mediate vascular endothelial growth factor secretion but not host cell adherence.
Level 5 - mechanism / opinion, no new human data
In vitro laboratory bench study evaluating cell culture mechanisms without human subjects.
PubMed 16926391 · doi:10.1128/IAI.00663-06
What was done
Researchers examined the interaction between several Bartonella quintana strains (JK-31, 2-D70, Toulouse, and Munich) and cultured human macrophage (THP-1) and epithelial (HeLa 229) cell lines. They measured vascular endothelial growth factor (VEGF) secretion (compared to B. henselae Marseille), evaluated cell surface expression of variable outer membrane proteins (Vomps) via immunofluorescence and electron microscopy, and measured host cell adherence rates.
What was found
Only B. quintana strain JK-31 induced VEGF secretion from THP-1 and HeLa 229 cells similar to B. henselae Marseille, whereas strains 2-D70, Toulouse, and Munich failed to induce secretion. Strains lacking VEGF induction did not express Vomps on their surfaces. The induction of VEGF secretion by strain JK-31 was not accompanied by increased host cell adherence rates compared with Vomp-negative strains. No exact numerical values or statistics were reported in the abstract.
Why it matters
This study indicates that B. quintana Vomps drive host angiogenic reprogramming via VEGF upregulation rather than facilitating host cell adhesion.
Limits
The findings are limited to in vitro cell line models without in vivo validation. The abstract reports no numerical values, sample sizes, replicate counts, or measures of variance.
Cited by
- supports Elevated VEGF levels occur in Long COVID, Bartonella infections, and cancer.