Human leukocyte antigen (HLA)-B, DRB1, and DQB1 allotypes associated with disease and protection of trachoma endemic villagers.
OBJECTIVE
Trachoma remains the leading preventable infectious cause of blindness in developing countries. Human leukocyte antigen (HLA) associations with ocular disease severity and persistent Chlamydia trachomatis infection of Tanzanians living in trachoma-endemic villages were examined to determine possible protective candidate allotypes for vaccine development.


METHODS
Buccal swab scrapes were taken from subjects in the Trichiasis Study Group (TSG), which studied females only, and the Family Trachoma Study (FTS), which compared persistently infected probands who had severe disease with disease-free siblings and parents. DNA was purified for polymerase chain reaction sequence-specific oligonucleotide identification of HLA-DRB1, DQB1, and B allotypes. Infection was detected from conjunctival scrapes using a C. trachomatis-specific PCR-enzyme immunoassay for the MOMP-1 gene.


RESULTS
In the TSG, DR*B11 (odds ratio [OR], 0.48; 95% confidence interval [CI], 0.26-0.90; P=0.02) was significantly associated with lack of trichiasis, whereas HLA-B*07 (OR, 3.26; 95% CI, 1.42-7.49; P=0.004) and HLA-B*08 (OR, 5.12; 95% CI, 1.74-15.05; P=0.001) were associated with trichiasis. In addition, HLA-B*14 was significantly associated with inflammatory trachoma + follicular trachoma (OR, 3.76; 95% CI, 1.70-8.33; P=0.04). There were no significant allele frequencies for the FTS.


CONCLUSIONS
The data suggest that HLA-DRB*11 may offer protection from trichiasis in trachoma hyperendemic villages. Complete allotype identification and designation of its respective protective CD4(+) T-cell antigens could provide a testable candidate vaccine for blindness prevention. Additionally, buccal swab DNA was sufficiently stable when acquired under harsh field conditions and stored long term in the freezer for low-resolution HLA typing.
Abbas
Muneer
M
National Human Genome Center, Howard University, Washington, DC, USA.
Bobo
Linda D
LD
Hsieh
Yu-Hsiang
YH
Berka
Noureddine
N
Dunston
Georgia
G
Bonney
George E
GE
Apprey
Victor
V
Quinn
Thomas C
TC
West
Sheila K
SK
D000293:Adolescent; D000328:Adult; D000483:Alleles; D002692:Chlamydia trachomatis / Q000472:pathogenicity; D004269:DNA, Bacterial / Q000032:analysis; D019353:Endemic Diseases; D005260:Female; D005434:Flow Cytometry; D005787:Gene Frequency; D005838:Genotype; D015235:HLA-B Antigens / Q000235:genetics*; D006683:HLA-DQ Antigens / Q000235:genetics*; D059866:HLA-DQ beta-Chains; D006684:HLA-DR Antigens / Q000235:genetics*; D059811:HLA-DRB1 Chains; D006650:Histocompatibility Testing; D006801:Humans; D009061:Mouth Mucosa; D009693:Nucleic Acid Hybridization; D018272:Porins / Q000235:genetics; D012424:Rural Population; D013636:Tanzania / Q000453:epidemiology; D014141:Trachoma / Q000453:epidemiology / Q000235:genetics* / Q000517:prevention & control*
D004269:DNA, Bacterial; D015235:HLA-B Antigens; D006683:HLA-DQ Antigens; D059866:HLA-DQ beta-Chains; C069051:HLA-DQB1 antigen; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; C508422:HLA-DRB1*11 antigen; D018272:Porins; C071677:omp1 protein, Chlamydia trachomatis