Anti-HLA antibody profile of Turkish patients with end-stage renal disease

Prevalence and risk factors of antibodies towards HLA Class I and Class II in Malaysian renal transplant candidates

Antibody-mediated rejection (AMR) still persists as the major hurdle towards successful renal allograft survival. This paper aims to report on the HLA antibody landscape of renal transplant candidates in Malaysia. A total of 2,219 adult samples from 2016 to 2019 were analysed for anti-HLA antibodies using solid-phase assay. Our findings highlight the prevalence and risk factors for antibodies against HLA antigens in renal transplant settings, which could be beneficial for selecting compatible recipients from deceased organ donors. To the best of our knowledge, this study is the first to demonstrate that ethnic Malay and Chinese showed significantly higher prevalence of anti-HLA antibodies. Based on our multivariate analysis: (i) female gender was associated with higher risk for panel reactive antibodies (PRAs) against Class I, Class II, and Class I and II (p < 0.001); (ii) older patients (≥ 38 years old) were associated with higher risk of positivity against Class I, Class II and Class I and II (p < 0.001); (iii) Malays showed significant association with Class II antibodies (p = 0.035); Chinese patients presented with higher risk of PRA positivity against Class II (p < 0.001) and Class I and II (p = 0.01); Indians were significantly associated with higher risk of HLA antibody sensitization against Class I (p = 0.022), Class II (p = 0.026) and Class I and II (p = 0.05). Thus, our findings suggested that female gender, older age (≥ 38 years old) and ethnicity may serve as independent risk factors for HLA antibody sensitization in adult renal transplant candidates.

High soluble CD30 levels and associated anti-HLA antibodies in patients with failed renal allografts

INTRODUCTION

Serum soluble CD30 (sCD30), a 120-kD glycoprotein that belongs to the tumor necrosis factor receptor family, has been suggested as a marker of rejection in kidney transplant patients. The aim of this study was to evaluate the relationship between sCD30 levels and anti-HLA antibodies, and to compare sCD30 levels in patients undergoing hemodialysis (HD) with and without failed renal allografts and transplant recipients with functioning grafts.

METHODS

100 patients undergoing HD with failed grafts (group 1), 100 patients undergoing HD who had never undergone transplantation (group 2), and 100 kidney transplant recipients (group 3) were included in this study. Associations of serum sCD30 levels and anti-HLA antibody status were analyzed in these groups.

RESULTS

The sCD30 levels of group 1 and group 2 (154 ± 71 U/mL and 103 ± 55 U/mL, respectively) were significantly higher than those of the transplant recipients (group 3) (39 ± 21 U/mL) (p&lt;0.001 and p&lt;0.001). The serum sCD30 levels in group 1 (154 ± 71 U/mL) were also significantly higher than group 2 (103 ± 55 U/mL) (p&lt;0.001). Anti-HLA antibodies were detected in 81 (81%) and 5 (5%) of patients in groups 1 and 2, respectively (p&lt;0.001). When multiple regression analysis was performed to predict sCD30 levels, the independent variables in group 1 were the presence of class I anti-HLA antibodies (β = 0.295; p = 0.003) and age (β = -0.272; p = 0.005), and serum creatinine (β = 0.218; p = 0.027) and presence of class II anti-HLA antibodies (standardized β = 0.194; p = 0.046) in group 3.

CONCLUSIONS

Higher sCD30 levels and anti-HLA antibodies in patients undergoing HD with failed renal allografts may be related to higher inflammatory status in these patients.

Analysis of the Humoral Immune Response to Human Leukocyte Antigens in Turkish Renal Transplant Candidates and Relationship Between Autoimmune Disorders

BACKGROUND

Pre-transplant sensitization to human leukocyte antigens (HLA) is a risk factor for graft failure. The purpose of the current single-center study was to evaluate humoral immune response to HLA antigens and the possible relationship between anti-HLA antibody titer and autoimmune disorders in renal transplant candidates.

METHODS

A total of 435 renal transplant candidates were analyzed; 50 sensitized patients were enrolled in this study. The HLA typing was performed by use of enzyme-linked immunoassay combined with Luminex technology. The patients were questioned for clinical evidence of hypothyroidism and systemic lupus erythematosus (SLE) and investigated for anti-nuclear antibody (ANA), anti-double-stranded DNA (anti-dsDNA), anti-thyroglobulin (anti-TG), anti-thyroid peroxidase (anti-TPO) antibodies, and thyroid function tests.

RESULTS

Among 50 patients with positive panel reactive antibody, 24 (48%) were positive for class I and negative for class II, 12 (24%) were negative for class I and positive for class II, and 14 (28%) were positive for both classes I and II. The specificities of anti-HLA antibodies-A23, A68, A69, B27, B49, DR6, and DR8-were the most frequent. ANA and anti-dsDNA antibodies were not correlated with either clinical symptoms of SLE or anti-HLA antibody titer of renal transplant candidates. Similarly, anti-TG and anti-TPO antibodies were not correlated with clinical hypothyroidism or anti-HLA antibody titer.

CONCLUSIONS

Our data have demonstrated the profile of anti-HLA antibodies in patients who were on the renal transplant waiting list in Turkey. The most frequent specificities of anti-HLA antibodies were A23, A68, A69, B27, B49, DR6, and DR8. There was no association between anti-HLA antibody titer and clinical and laboratory evidence of SLE and hypothyroidism.

Evaluation of the humoral immune response to human leukocyte antigens in Brazilian renal transplant candidates

Pre-transplant sensitization to human leukocyte antigens (HLA) is a risk factor for graft failure. Studies of the immunological profile related to anti-HLA antibodies in Brazilian renal transplant candidates are few. In this study, we evaluated the humoral immune response to HLA antigens in 269 renal transplant candidates, in Paraná State, Brazil. The HLA typing was performed by the polymerase chain reaction sequence-specific oligonucleotide method (PCR-SSO) combined with Luminex technology, using an SSO-LABType commercial kit (One Lambda, Inc., Canoga Park, CA, USA). The percentages of panel-reactive antibodies (PRA) and the specificity of anti-HLA antibodies were determined using the LS1PRA and LS2PRA commercial kits (One Lambda, Inc.). The PRA-positive group consisted of 182 (67.7%) patients, and the PRA-negative group of 87 (32.3%) patients. The two groups differed significantly only with respect to gender. Females were the most sensitized. Among the 182 patients with PRA- positive, 62 (34.1%) were positive for class I and negative for class II, 39 (21.4%) were negative for class I and positive for class II, and 81 (44.5%) were positive for both classes I and II. The HLA-A*02, A*24, A*01, B*44, B*35, B*15, DRB1*11, DRB1*04 and DRB1*03 allele groups were the most frequent. The specificities of anti-HLA antibodies were more frequent: A34, B57, Cw15, Cw16, DR51, DQ8 and DP14. This study documented the profile of anti-HLA antibodies in patients with chronic renal failure who were on waiting lists for an organ in Paraná, and found high sensitization to HLA antigens in the samples.