Diabetes Care, Vol 17, Issue 9 970-976, Copyright © 1994 by American Diabetes Association
Children with newly diagnosed IDDM have increased levels of antibodies to bovine serum albumin but not to ovalbumin. Childhood Diabetes in Finland Study Group
T Saukkonen, E Savilahti, O Vaarala, ET Virtala, J Tuomilehto and HK Akerblom
Children's Hospital, University of Helsinki, Finland.
OBJECTIVE--To study the humoral immune response to bovine serum albumin
(BSA) and ovalbumin (OA) in children with newly diagnosed insulin-dependent
diabetes mellitus (IDDM). RESEARCH DESIGN AND METHODS--We examined serum
samples from 505 children 0.8-14.9 years of age with newly diagnosed IDDM
for antibodies to BSA and OA by enzyme-linked immunosorbent assay (ELISA).
We also had two control groups: 85 unrelated control children (0.8-7.1
years of age) and 395 nondiabetic siblings (3.0-14.9 years of age). The
specificity of antibodies detected in ELISA was confirmed by immunoblotting
in a subset of sera with varying levels of antibodies. RESULTS--Diabetic
children < 7 years of age had a significantly higher level of IgG
(immunoglobulin) antibodies to BSA than did unrelated control children (P
< 0.0001). The difference was greatest in the youngest group of
children, 0.8-2.9 years of age. IgA antibodies to BSA were detected more
frequently among diabetic than control children (P = 0.0009). Levels of IgG
and IgA antibodies to ovalbumin did not differ between diabetic and control
children. Diabetic children 3.0-14.9 years of age also had higher levels of
IgG and IgA antibodies to BSA than did their age- and sex-matched
nondiabetic siblings (P = 0.02 and P < 0.0001, respectively). Those
siblings who contracted IDDM during the follow-up period (n = 15) had a
measurable level of IgA antibodies to BSA more often than did those who
remained nondiabetic (60 and 34%, respectively; P = 0.04). Neither before
nor after diagnosis of IDDM was there any significant trend in antibody
levels. CONCLUSIONS--A high level of antibodies to BSA commonly associates
with IDDM, whereas the humoral immune response to OA is similar in diabetic
and nondiabetic children.