gms | German Medical Science

Deutscher Rheumatologiekongress 2021, 49. Kongress der Deutschen Gesellschaft für Rheumatologie (DGRh), 35. Jahrestagung der Deutschen Gesellschaft für Orthopädische Rheumatologie (DGORh), Wissenschaftliche Herbsttagung der Gesellschaft für Kinder- und Jugendrheumatologie (GKJR)

15.09. - 18.09.2021, virtuell

Blood CD3-(CD56 or 16)+ natural killer cell distributions are heterogeneous in healthy adults and suppressed by azathioprine in patients with ANCA-associated vasculitides

Meeting Abstract

  • Wolfgang Merkt - Department of Hematology, Oncology and Rheumatology, Internal Medicine V, University Hospital of Heidelberg, Heidelberg
  • Ulrich Salzer - Department of Rheumatology and Clinical Immunology, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau
  • Raoul Bergner - Department of Rheumatology, Nephrology, Haemato-Oncology, Klinikum Ludwigshafen, Ludwigshafen
  • Jens Thiel - Department of Rheumatology and Clinical Immunology, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau
  • Ilona Jandova - Department of Rheumatology and Clinical Immunology, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau
  • Ana Cecilia Venhoff - Department of Rheumatology and Clinical Immunology, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau
  • Nils Venhoff - Department of Rheumatology and Clinical Immunology, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau

Deutsche Gesellschaft für Rheumatologie. Deutsche Gesellschaft für Orthopädische Rheumatologie. Gesellschaft für Kinder- und Jugendrheumatologie. Deutscher Rheumatologiekongress 2021, 49. Kongress der Deutschen Gesellschaft für Rheumatologie (DGRh), 35. Jahrestagung der Deutschen Gesellschaft für Orthopädische Rheumatologie (DGORh), Wissenschaftliche Herbsttagung der Gesellschaft für Kinder- und Jugendrheumatologie (GKJR). sine loco [digital], 15.-18.09.2021. Düsseldorf: German Medical Science GMS Publishing House; 2021. DocVK.08

doi: 10.3205/21dgrh175, urn:nbn:de:0183-21dgrh1750

Published: September 14, 2021

© 2021 Merkt et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 License. See license information at http://creativecommons.org/licenses/by/4.0/.


Outline

Text

Introduction: Cytotoxic Natural Killer (NK) cells are increasingly recognized as a powerful tool to induce targeted cell death in cancer and autoimmune diseases. Still, basic blood NK cell parameters are poorly defined. The aims of this study were 1) to establish reference values of NK cell counts and percentages in healthy adults; 2) to describe these parameters in the prototype autoimmune disease group ANCA-associated vasculitis (AAV); and 3) to investigate whether NK cell counts and percentages may be used as activity biomarkers in the care of AAV patients, as suggested by a preceding study.

Methods: CD3-(CD56 or 16)+ NK cell counts and percentages were determined in 120 healthy adults. Lymphocyte subset and clinical data from two German vasculitis centers were analyzed retrospectively (in total 407 measurements, including 201/49/157 measurements from 64/16/39 patients with granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA) and eosinophilic granulomatosis with polyangiitis (EGPA), respectively).

Results: CD3-(CD56 or 16)+ NK cell counts and percentages in healthy adults were highly variable, not Gaussian distributed and independent of age and sex. NK cell percentages ranged from 1.9 to 37.9% of lymphocytes, and were significantly more dispersed in AAV (0.3 to 57.6%), while the median percentage was not different between AAV and healthy donors. In contrast, median NK cell counts were significantly lower in AAV compared to healthy donors. Sub-group analyses revealed that NK cell counts were low independent of AAV entity and disease activity. Azathioprine therapy was associated with significantly lower NK cell counts and percentages compared to non-azathioprine therapies. In 13.6% of azathioprine-treated patients, percentages were </= 1% which may be interpreted as temporary NK cell deficiency. NK cell counts and percentages could not separate active from inactive AAV.

Conclusion: NK cell counts and percentages in blood are heterogeneous and can presently not be recommended as biomarker in clinical care of AAV patients. Azathioprine treatment was associated with significantly low NK cells. These findings may be relevant for the development of drugs that aim at exploiting NK cell cytotoxicity and may help to identify patients at risk to develop malignant or infectious co-morbidities.

Disclosures: W.M. has received consulting fees, speaking fees, and/or honoraria from Novartis and Roche (less than $10,000 each). N.V. has received consulting fees, speaking fees, and/or honoraria from Roche, Novartis and Medac (less than $10,000). R.B. has received speaking fees from Abbvie, Bristol Myers Squibb, Chugai, Novartis and Roche, less than 2000€ each. The remaining authors declared no competing interests.