Change of glutamic acid decarboxylase antibody and protein tyrosine phosphatase antibody in Chinese patients with acute-onset type 1 diabetes mellitus.
BACKGROUND
Glutamic acid decarboxylase antibody (GADA) and protein tyrosine phosphatase antibody (IA-2A) are two major autoantibodies, which exert important roles in the process of type 1 diabetes mellitus (T1D). Our study aimed to investigate the changes in positivity and titers of GADA and IA-2A during the course of Chinese acute-onset T1D patients and their relationships with clinical features.


METHODS
Two hundreds and forty-seven Chinese newly diagnosed acute-onset T1D patients were consecutively recruited. GADA and IA-2A were detected at the time of diagnosis, one year later, 3-5 years later after diagnosis during the follow-up; all the clinical data were recorded and analyzed as well.


RESULTS
During the course of acute-onset T1D, the majority of patients remained stable for GADA or IA-2A, however, a few patients changed from positivity to negativity and fewer patients converted from negativity to positivity. The prevalence of GADA was 56.3% at diagnosis, decreasing to 50.5% one year later, and 43.3% 3-5 years later while the corresponding prevalence of IA-2A were 32.8%, 31.0% and 23.3%, respectively. The median GADA titers were 0.0825 at diagnosis, declining to 0.0585 one year later and 0.0383 3-5 years later (P < 0.001), while the corresponding median titers were 0.0016, 0.0010, 0.0014 for IA-2A, respectively. Fasting C-peptide (FCP) and postprandial C-peptide 2 hours (PCP2h) levels of GADA or IA-2A negativity persistence patients were higher than those of positivity persistence and negativity conversion patients (P < 0.05) which indicated GADA or IA-2A negativity persistence T1D patients had a less loss of β cell function.


CONCLUSIONS
Our data suggest that repeated detection of GADA and IA-2A are necessary for differential diagnosis of autoimmune diabetes and the indirect prediction of the β cell function in Chinese patients.
Diabetes Center, Institute of Metabolism and Endocrinology, Second Xiangya Hospital, Key Laboratory of Diabetes Immunology, Ministry of Education, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha, Hunan 410011, China.
Chen
C
Chao
Gan
G
Huang
Xia
X
Li
Lin
L
Yang
Jian
J
Lin
Ping
P
Jin
Shuo-Ming
SM
Luo
Yi-Yu
YY
Zhang
Ling-Ling
LL
Pan
Zhi-Guang
ZG
Zhou
D000293:Adolescent; D000328:Adult; D000368:Aged; D000906:Antibodies / Q000627:therapeutic use*; D044466:Asian People; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000188:drug therapy* / Q000276:immunology; D005260:Female; D005968:Glutamate Decarboxylase / Q000276:immunology*; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D017027:Protein Tyrosine Phosphatases / Q000276:immunology*; D055815:Young Adult
D000906:Antibodies; D005968:Glutamate Decarboxylase; D006442:Glycated Hemoglobin; D017027:Protein Tyrosine Phosphatases