Association of various inflammatory diseases with human leukocyte antigens B27, B7, Bw4 and Bw6 in patients with SSA

Association of Genetic Marker HLA-B27 with Spondyloarthritis In A Tertiary Care Centre In South India

Human leukocyte antigens (HLA) are gene products found in the major histocompatibility complex, aiding in differentiation of “self” from “non-self” antigens, and is crucial for the communication between immune cells of the human body. HLA-B27, in specific, has a strong interrelation with different types of Spondyloarthritis (SpA). The aim of this study is to study the frequency of HLA-B27 in suspected Spondyloarthritis patients presenting with axial and peripheral joint involvement, who attended our tertiary care centre from August-2017 to January-2021. Patients fulfilling Assessment of Spondyloarthritis International Society (ASAS) criteria for Spondyloarthritis were included in the study, and were further classified into Spondyloarthritis sub-groups. Blood samples were collected for CRP and ESR tests along with HLA-B27 detection by RT-PCR method. Magnetic resonance imaging was done for sacroiliac joints in patients with lower back pain. Analysis of 289 samples of SpA patients revealed 156 (54%) to be HLA-B27 positive and 133 (46%) to be HLA-B27 negative. There were 98 patients (63%) with Ankylosing spondylitis, 33 (21%) had Reactive arthritis, 19 (12%) had Psoriatic arthritis, 6 (4%) had Undifferentiated Spondyloarthritis, and inflammatory bowel disease was diagnosed in 0% in HLA-B27 positive Spondyloarthritis patients. The frequency of HLA-B27 among the Spondyloarthritis (SpA) patients in our study was found to be 54% (156), more common clinical manifestation in men belonging to the age group of 16-25 years positive patients. Ankylosing spondylitis (AS) was found to be the most common sub-groups observed among the SpA patients.

Application of a Simple In-House PCR-SSP Technique for HLA-B* 27 Typing in Spondyloarthritis Patients

Background. Microlymphocytotoxicity (MLCT) and flowcytometry (FC) are the conventional serological methods to detect HLA-B* 27. Due to some disadvantages in these methods, most of the HLA laboratories have now switched over to molecular methods. Molecular techniques based on commercial kits are expensive; as such many laboratories with limited funds in developing countries cannot afford these techniques. Aims. Our main aim was to standardize a simple inexpensive in-house PCR-SSP technique for HLA-B* 27 typing. Materials and Methods. Sequence Specific primers were designed to amplify all the subtypes of B* 27 using IMGT-HLA sequence database. Accuracy was checked by retyping of 90 PCR-SSOP typed controls. Results. The presence of 149 bp specific band with control band on 2% agarose gel showed B* 27 positivity. No discrepancies were found when compared with PCR-SSOP results. The frequency of HLA-B* 27 was found to be significantly increased (68.75% versus 4.40%, O.R 46.909: P value 6.62E − 32) among 700 SpA patients as compared to controls. Clinically, 54% of patients had polyarticular arthritis with SI joints involvement (68%) and restricted spine flexion (60%). Conclusion. In-house PCR-SSP technique is very simple and inexpensive technique to detect B* 27 allele, which was strongly associated with SpA patients from Western India.