Donor-specific Anti-HLA Alloantibody in Kidney Transplant Recipients with COVID-19 Exhibit a Different Immunoglobulin Class and Subclass Profile When Compared to Anti-SARS-CoV-2 Antibodies

A. Girnita¹, L. Wang¹, M. Fernandez-Vina¹, E. Woodle², P. Ahearn¹, T. Yalamarti¹, M. Menon³, Y. Azzi⁴, M. Melcher¹, R. Bray⁵, H. Gebel⁵, E. Akalin⁴, P. Cravedi³, J. S. Maltzman¹

¹Stanford University, Palo Alto, CA, ²University of Cincinnati, Cincinnati, OH, ³Icahn School of Medicine, NYC, NY, ⁴Einstein School of Medicine, NYC, NY, ⁵Emory University, Atlanta, GA

Meeting: 2021 American Transplant Congress

Abstract number: LB 63

Keywords: COVID-19, HLA antibodies

Topic: Clinical Science » Infectious Disease » COVID-19

Session Information

Session Name: COVID-19

Session Type: Poster Abstract

Session Date & Time: None. Available on demand.

Location: Virtual

*Purpose: Both anti-HLA and anti-SARS-CoV-2 antibodies target protein antigens. The aim of the present study was to compare the class and subclass profile of such antibodies in a cohort of kidney transplant patients.

*Methods: We detected and identified anti-HLA and anti-SARS-CoV-2 antibody in 48 kidney transplant recipients who were hospitalized for SARS-CoV-2 PCR+ infection. Anti-HLA antibodies were detected by single-antigen bead Luminex assay, with IgG class, and IgG1-2-3-4 subclass secondary antibody. Anti-SARS-CoV-2 antibodies were also detected by Luminex assay directed against 5 distinct viral epitopes including the nucleocapsid protein as well as multiple regions of the spike protein. The secondary antibodies addressed total IgG, IgG1-2-3-4, IgM and IgA class/subclasses.

*Results: The antibody profile (Table 1) included 12/48 cases of donor-specific anti-HLA antibodies, and 43/48 cases with anti-SARS-CoV2 antibodies. The majority of HLA-specific antibodies targeted HLA-DQ, with a dominant IgG class and an IgG1+IgG2+IgG3 subclass prevalence. However, anti-SARS-CoV2 antibody profile was characterized by increased prevalence of IgM (38/43, 79%) and IgA (41/42, 85%), and a lower prevalence of IgG2.

*Conclusions: Overall, these data suggests that kidney transplant recipients with Covid-19 exhibit a humoral immune response both to donor-HLA and SARS-CoV-2. Although both are protein antigens, the allo-immune response has a high-IgG/low IgA pattern, while the Covid-19 antibody profile includes high IgA. Additional follow-up is needed to determine if the increased IgA is a consistent marker of anti-SARS-CoV-2 antibody response.

To cite this abstract in AMA style:

Girnita A, Wang L, Fernandez-Vina M, Woodle E, Ahearn P, Yalamarti T, Menon M, Azzi Y, Melcher M, Bray R, Gebel H, Akalin E, Cravedi P, Maltzman JS. Donor-specific Anti-HLA Alloantibody in Kidney Transplant Recipients with COVID-19 Exhibit a Different Immunoglobulin Class and Subclass Profile When Compared to Anti-SARS-CoV-2 Antibodies [abstract]. Am J Transplant. 2021; 21 (suppl 3). https://atcmeetingabstracts.com/abstract/donor-specific-anti-hla-alloantibody-in-kidney-transplant-recipients-with-covid-19-exhibit-a-different-immunoglobulin-class-and-subclass-profile-when-compared-to-anti-sars-cov-2-antibodies/. Accessed May 16, 2025.

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