<abstract xmlns="http://www.w3.org/1999/xhtml">

<sec><h3>BACKGOUND</h3>
<p>The prevalence of rheumatoid arthritis (RA) and its specific autoantibodies varies in different populations. This variability depends on the genetic polymorphism of the immune response genes among which the HLA system plays a major role.</p>
</sec>
<sec><h3>AIM</h3>
<p>We conducted a preliminary study of the distribution of HLA-DRB1 and HLA-DQB1 first field level alleles in a sample of 100 Albanian patients with RA.</p>
</sec>
<sec><h3>METHODS</h3>
<p>In this context, we studied the HLA-DRB1 and HLA-DQB1 first-level allele frequencies in 100 Albanian patients with RA and considering their rheumatoid factor (RF) and anti-citrullinated peptide antibodies (ACPA) serologic subgroups. We compared them with the respective frequencies in a population of 191 Albanian individuals without known pathology.</p>
</sec>
<sec><h3>RESULTS</h3>
<p>No differences were found between the controls and the RA patient group, but three statistically significant differences were found: an increase in DRB1<sup>*</sup>04 among ACPA-positive, RF-positive and ACPA-positive/ RF-positive patients, a significant decrease in DRB1<sup>*</sup>11 among ACPA-positive/RF-positive, and also a decrease in DRB1<sup>*</sup>13 among RF-positive patient subgroups. The frequencies of DRB1 allotypes in ACPA+ and RF+ patients compared to their counterpart ACPA− and RF−patient subgroups showed the predisposing effect of HLA-DRB1<sup>*</sup>04 for ACPA and RF seropositivity (p, respectively, 0.0008 and 0.0017) and the protective role of HLA-DRB1<sup>*</sup>11 for ACPA and RF positivity (p, respectively, 0.007 and 0.02). The same protective role from the RF positivity is also found with the HLA-DRB1<sup>*</sup>13 alleles (p = 0.007). As far as the DQB1 locus is concerned, a protective association has been found between the HLA-DQB1<sup>*</sup>06 alleles with both RF+ and RF+ ACPA+ positivity (p, respectively, 0.05 and 0.04) when comparing the control group with the respective RA patient subgroups. In ACPA+ and RF+ patients compared to the ACPA− and RF− patient subgroups, the only detected difference was between RF (+) and RF (−) patients (p =0.04).</p>
</sec>
<sec><h3>CONCLUSION</h3>
<p>The relatively low frequencies of DRB1<sup>*</sup>04 and high (DRB1<sup>*</sup>11 and DRB1<sup>*</sup>13) in the Albanian population might explain the rather low positivity rate of ACPA and RF antibodies among the Albanian RA patients. Our study demonstrates that DRB1<sup>*</sup>11, DRB1<sup>*</sup>13 and DQB1<sup>*</sup>06 may be negatively associated with RA. Conversely, DRB1<sup>*</sup>04 may confer susceptibility to RA in Albanian population.</p>
</sec>
</abstract>

BACKGOUND
The prevalence of rheumatoid arthritis (RA) and its specific autoantibodies varies in different populations. This variability depends on the genetic polymorphism of the immune response genes among which the HLA system plays a major role.

AIM
We conducted a preliminary study of the distribution of HLA-DRB1 and HLA-DQB1 first field level alleles in a sample of 100 Albanian patients with RA.

METHODS
In this context, we studied the HLA-DRB1 and HLA-DQB1 first-level allele frequencies in 100 Albanian patients with RA and considering their rheumatoid factor (RF) and anti-citrullinated peptide antibodies (ACPA) serologic subgroups. We compared them with the respective frequencies in a population of 191 Albanian individuals without known pathology.

RESULTS
No differences were found between the controls and the RA patient group, but three statistically significant differences were found: an increase in DRB1*04 among ACPA-positive, RF-positive and ACPA-positive/ RF-positive patients, a significant decrease in DRB1*11 among ACPA-positive/RF-positive, and also a decrease in DRB1*13 among RF-positive patient subgroups. The frequencies of DRB1 allotypes in ACPA+ and RF+ patients compared to their counterpart ACPA− and RF−patient subgroups showed the predisposing effect of HLA-DRB1*04 for ACPA and RF seropositivity (p, respectively, 0.0008 and 0.0017) and the protective role of HLA-DRB1*11 for ACPA and RF positivity (p, respectively, 0.007 and 0.02). The same protective role from the RF positivity is also found with the HLA-DRB1*13 alleles (p = 0.007). As far as the DQB1 locus is concerned, a protective association has been found between the HLA-DQB1*06 alleles with both RF+ and RF+ ACPA+ positivity (p, respectively, 0.05 and 0.04) when comparing the control group with the respective RA patient subgroups. In ACPA+ and RF+ patients compared to the ACPA− and RF− patient subgroups, the only detected difference was between RF (+) and RF (−) patients (p =0.04).

CONCLUSION
The relatively low frequencies of DRB1*04 and high (DRB1*11 and DRB1*13) in the Albanian population might explain the rather low positivity rate of ACPA and RF antibodies among the Albanian RA patients. Our study demonstrates that DRB1*11, DRB1*13 and DQB1*06 may be negatively associated with RA. Conversely, DRB1*04 may confer susceptibility to RA in Albanian population.

The Protective Effect of HLA-DRB1 and HLA-DQB1 Alleles to ACPA-Positive and RF-Positive RA in Albanian Population

South East European Journal of Immunology

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

BACKGOUND
The prevalence of rheumatoid arthritis (RA) and its specific autoantibodies varies in different populations. This variability depends on the genetic...

The Protective Effect of HLA-DRB1 and HLA-DQB1 Alleles to ACPA-Positive and RF-Positive RA in Albanian Population

Published Online: Jan 03, 2024

Page range: 24 - 28

Received: Apr 25, 2023

Accepted: May 24, 2023

DOI: https://doi.org/10.3889/seejim.2022.6037

Keywords
Rheumatoid arthritis, Human leukocyte antigens, Anti-citrullinated, Peptide antibodies, Rheumatoid factor

© 2023 Margarita Prifti-Kurti et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

The Protective Effect of HLA-DRB1 and HLA-DQB1 Alleles to ACPA-Positive and RF-Positive RA in Albanian Population

Published Online: Jan 03, 2024

Page range: 24 - 28

Received: Apr 25, 2023

Accepted: May 24, 2023

DOI: https://doi.org/10.3889/seejim.2022.6037

KeywordsRheumatoid arthritis, Human leukocyte antigens, Anti-citrullinated, Peptide antibodies, Rheumatoid factor

© 2023 Margarita Prifti-Kurti et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Keywords
Rheumatoid arthritis, Human leukocyte antigens, Anti-citrullinated, Peptide antibodies, Rheumatoid factor