Regional variation in anti-endotoxin core antibody levels in healthy and preoperative surgical populations

Introduction

Endotoxin has a central role in sepsis and organ dysfunction after surgery. Levels of one of our natural defences against endotoxin, antibodies to endotoxin core (EndoCAb), are independent predictors of postoperative outcome [1]. There is a heterogeneity in EndoCAb levels between European and North American healthy donor populations that remains unexplained [2].

Methods

Blood samples from healthy blood donors were collected in London, UK and compared with levels of baseline EndoCAb in previous studies. An ELISA assay of serum EndoCAb IgG (n = 165) and IgM (n = 65*) levels was performed and expressed as median units per ml (MU/ml) [3].

Results

The median serum EndoCAb IgG and IgM levels in this population were 189.7 (41.8–1023) MU/ml and 222.5 (42.3–913.9) MU/ml, respectively (Fig. 1).

Figure 1

Conclusion

EndoCAb levels are higher in London healthy donors than in the Scottish population. US cardiac patients show higher IgG levels than UK cardiac patients and Scottish healthy donors, but are similar to London healthy donors. US surgery patients show higher IgM levels than all groups but are similar to London healthy donors. Differences may be due to prior exposure to endotoxin, different disease process, differences in sampling and patient management, or genetic variation between countries. We are collecting further healthy donor samples to assess a larger cohort of EndoCAb levels in London.