Antibodies against N-homocysteinylated proteins and their determinants in patients on long-term hemodialysis.
BACKGROUND
The factors that determine the level of antibodies against N-homocysteinylated (N-Hcy) proteins have not been established so far. The clinical significance of these antibodies and their effect on cardiovascular (CV) risk in patients with end-stage renal disease (ESRD) are still unknown.


OBJECTIVE
The aim of this study was to identify the factors that determine the level of antibodies against N-Hcyalbumin and N-Hcy hemoglobin in patients on long-term hemodialysis (HD).


METHODS
The study involved 247 subjects on long-term HD (110 women, 137 men; age range, 23-89 years) and 60 controls matched for age, sex, and CV risk factors (serum creatinine level <140 micromol/l). Serum antibodies against N-Hcyalbumin and N-Hcyhemoglobin were determined using an in-house enzyme-linked immunosorbent assay. Total homocysteine (tHcy), folate, and 8-isoprostaglandin F2alpha (8-iso-PGF(2alpha)) were also measured.


RESULTS
Patients on HD had higher serum levels of anti-N-Hcy-albumin (absorbancy at 490 nm: 0.56 [0.49-0.623] vs. 0.259 [0.198-0.338], P <0.0001) and anti-N-Hcy-hemoglobin antibodies (0.659 [0.597-0.723] vs. 0.379 [0.289-0.442], P <0.0001) as compared with controls. The level of both antibodies correlated with tHcy (r = 0.56, P <0.0001 and r = 0.67, P <0.0001, respectively), 8-iso-PGF(2alpha) (r = 0.48, P <0.0001 and r = 0.63, P <0.0001, respectively), and folate (r = -0.18, P = 0.0054 and r = -0.38, P <0.0001, respectively), but not with HD duration, the initial cause of ESRD, and CV comorbidity.


CONCLUSIONS
In HD patients, tHcy is an independent predictor of antibodies against N-Hcy proteins. Folate and 8-iso-PGF(2alpha) concentrations were not independently associated with the levels of both antibodies.
Kolarz
Maciej
M
Hemodialysis Unit, Avitum Poland, Miechów, Poland. mkol@mp.pl
Wyroślak
Janusz
J
Zbróg
Zbigniew
Z
Kraśniak
Andrzej
A
Rogulska
Joanna
J
Padjas
Agnieszka
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000906:Antibodies / Q000032:analysis*; D005260:Female; D006454:Hemoglobins / Q000276:immunology*; D006710:Homocysteine / Q000031:analogs & derivatives* / Q000276:immunology; D006801:Humans; D007676:Kidney Failure, Chronic / Q000276:immunology* / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D018384:Oxidative Stress / Q000276:immunology; D006435:Renal Dialysis / Q000009:adverse effects*; D012709:Serum Albumin / Q000276:immunology*; D055815:Young Adult
D000906:Antibodies; D006454:Hemoglobins; C502359:N-homocysteinylated albumin; D012709:Serum Albumin; D006710:Homocysteine