Locally produced anti-phosphorylcholine and anti-oxidized low-density lipoprotein antibodies in gingival crevicular fluid from aggressive periodontitis patients.
BACKGROUND
Sera from patients with periodontal attachment loss contain higher concentrations of IgG anti-phosphorylcholine (anti-PC) than sera from healthy subjects. Furthermore, a large proportion of plaque bacteria bear PC-containing surface antigens, implicating the oral flora as a source of immunogen for anti-PC. Additionally, anti-PC is cross-reactive with a variety of oral bacterial antigens and human antigens such as oxidized low-density lipoprotein (oxLDL). We hypothesized that, if the oral flora is a source of PC antigens, then we should be able to detect local anti-PC and anti-oxLDL production in gingival crevicular fluid (GCF).


METHODS
To test this, we collected 66 GCF samples from 15 patients with aggressive periodontitis and examined both the GCF samples and serum samples for their content of IgG anti-PC, IgG anti-LDL, and IgG anti-oxLDL by enzyme-linked immunosorbent assay. We also determined levels of anti-tetanus toxoid (anti-TT) as a non-oral antigen control. Serum and GCF concentrations of serum albumin (HSA) were also determined for use as a dilution marker. A conservative GCF:serum antibody ratio of greater than 1.5 was considered to be evidence of local antibody production.


RESULTS
For the non-oral antigen TT, only one out of 62 samples contained locally produced antibody. Eight out of 64 samples (7 from a single subject) demonstrated local production of anti-LDL. In contrast, 28 out of 66 samples demonstrated local production of anti-PC, and 47 out of 66 samples contained locally produced anti-oxLDL. It was observed that A. actinomycetemcomitans strains containing or devoid of PC could absorb anti-oxLDL from human sera. Although there was a correlation between the ratios of anti-PC and anti-oxLDL (Spearman's rho = 0.35, P = 0.0037), local production of both antibodies was found in only 17 out of 65 samples, indicating that these antibodies are not always reflective of reactivity to the same antigens.


CONCLUSIONS
The local production of anti-PC and anti-oxLDL further implicates the oral flora as a source of antigen that may mediate immune reactions of relevance to cardiovascular and other systemic diseases.
Schenkein
Harvey A
HA
Virginia Commonwealth University School of Dentistry, Clinical Research Center for Periodontal Disease, Richmond, VA 23298-0566, USA. haschenk@vcu.edu
Berry
C Rennie
CR
Burmeister
John A
JA
Brooks
Carol N
CN
Best
Al M
AM
Tew
John G
JG
D000208:Acute Disease; D000328:Adult; D000704:Analysis of Variance; D000907:Antibodies, Bacterial / Q000097:blood / Q000276:immunology*; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005883:Gingival Crevicular Fluid / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D008077:Lipoproteins, LDL / Q000097:blood / Q000276:immunology*; D008297:Male; D010518:Periodontitis / Q000097:blood / Q000276:immunology* / Q000382:microbiology; D010767:Phosphorylcholine / Q000097:blood / Q000276:immunology*; D012709:Serum Albumin / Q000276:immunology; D013745:Tetanus Toxoid / Q000097:blood / Q000276:immunology
D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D008077:Lipoproteins, LDL; D012709:Serum Albumin; D013745:Tetanus Toxoid; C099252:oxidized low density lipoprotein; D010767:Phosphorylcholine