ICAP

Welcome to ANApatterns.org, the official website for the International Consensus on Antinuclear Antibody (ANA) Patterns (ICAP). ICAP was initiated as a workshop aiming to thoroughly discuss and to promote consensus regarding the richness and nuances of morphological patterns observed in the indirect immunofluorescence assay on HEp-2 cells (HEp-2 IFA). The ICAP initiative was implemented at the 12th International Workshop on Autoantibodies and Autoimmunity (IWAA, São Paulo, Brazil) by members of the Autoantibody Standardization Committee (ASC), a subcommittee of the International Union of Immunological Societies (IUIS) Quality Assessment and Standardization Committee and affiliated with the Centers for Diseases Control and Prevention (CDC). The ICAP committee is operating as an ASC sub-committee.

Illustrative images were submitted for each pattern and ICAP members voted and selected the most representative ones paying attention to pixel dimension, resolution, and size. The highest ranked images for each pattern are displayed on this web site. (For an introduction of the website with some graphic images, click here.)

The ICAP committee acknowledges that the term ANA is outdated as discussed in several publications [1, 2] and yet ANA is still most commonly used in the current literature. We have proposed to use the term HEp-2 IFA to precisely describe the test in practice and used in most ICAP publications [3, 4]. Anti-Cell (AC) is used in ICAP coding of HEp-2 IFA patterns [3, 4]. Although the term anti-cellular antibody has been used in place of ANA by ICAP [2] and others [1], there is support for and reservations about its accuracy because the term “anti-cellular" also encompasses a wide spectrum of autoantibodies detected by other assays – e.g. ANCA, ASMA, APCA.

  1. Agmon-Levin, N., et al., International recommendations for the assessment of autoantibodies to cellular antigens referred to as anti-nuclear antibodies. Ann Rheum Dis, 2014. 73(1): p. 17-23.
  2. von Muhlen, C.A., et al., How to report the antinuclear antibodies (anti-cell antibodies) test on HEp-2 cells: guidelines from the ICAP initiative. Immunol Res, 2021. 69(6): p. 594-608.
  3. Damoiseaux, J., et al., Clinical relevance of HEp-2 indirect immunofluorescent patterns: the International Consensus on ANA patterns (ICAP) perspective. Ann Rheum Dis, 2019. 78(7): p. 879-889.
  4. Chan, E.K.L., et al., Report of the First International Consensus on Standardized Nomenclature of Antinuclear Antibody HEp-2 Cell Patterns 2014-2015. Front Immunol, 2015. 6: p. 412.


 
Announcements and Updates
Mon, 26 Oct 2026
How can we improve standardization in autoantibody testing? In this IUIS webinar held on August 26, 2026, Luis Andrade and May Choi, with Maria Infantino as chair, discuss sources of variability in immunoassay performance, initiatives to improve standardization, and the role of artificial intelligence in HEp-2 indirect immunofluorescence image interpretation.

Organized by the IUIS Quality Assessment and Standardization Committee (QAS), this session offers insights for clinicians, laboratory professionals, and researchers working in autoimmune disease diagnostics.

Watch the recorded webinar

Wed, 07 Oct 2026

In memory of Karsten Conrad, who passed away on August 7, 2026

The Organizing Committee is pleased to announce the 18th Dresden Symposium on Autoantibodies. The symposium will bring together clinicians and scientists specializing in autoimmunity to exchange knowledge and discuss advances in basic and applied research on autoantigens, autoantibodies, and autoimmunity.

Chairs: Jan Damoiseaux (The Netherlands) and Christian Moritz (France). 
Honorary Chairmen: Yehuda Shoenfeld (Israel) and Marvin Fritzler (Canada).

Planned topics include:
Autoantibodies in neurology
Autoantibodies against the immune system
Autoantibodies in post-infectious ME/CFS

Autoantibodies in cancer

Resetting autoimmunity with CAR-T cell therapy
Regulatory affairs and autoimmune serology
Autoantibody screening: the need for differential approaches
Cutting-edge autoimmune serology: new autoantibodies, new technologies, and artificial intelligence
Future perspectives of autoimmune serology

We invite the ICAP community to save the date and join this international exchange on the future of autoimmune diagnostics.

Wed, 09 Sep 2026
Gabriel Carballo (Argentina) and Carlos von Mühlen (Brazil/USA) were invited to join, last July/2026, the First Ecuadorian Consensus on HEp-2 IFA in Quito, capital of Ecuador. Besides giving conferences on aspects of ANA HEp-2 IFA quality control and ICAP latest advances, the two ICAP board members actively  helped the local scientific community in establishing overarching consensus and harmonization principles for adoption by clinical laboratories and clinicians in that country. The meeting was organized by the Ecuadorian Society of Rheumatology and Zurita & Zurita Laboratories.



View all announcements


 
HEp-2 CIC Project

Despite the worldwide acceptance of ICAP recommendations by clinical laboratories, academic institutions and vitro diagnostic industries, there is still considerable heterogeneity regarding the iterpretation and reporting of HEp-2 among different laboratories. Click here

 
FAQ - Frequently Asked Questions

Submit your question to ICAP. Only confirmed users can submit a question. If you are not registered, click here to start. Submitted questions will be routed to ICAP Coordinators Edward K. L. Chan (echan@ufl.edu) and Luis E. C. Andrade (luis.andrade@unifesp.br). Simple questions will be answered within 24 hours. Complex questions will be routed to several ICAP members either for a consensus or to provide different viewpoints and it may take 72 hours to 2 weeks for an answer. click here

 
 
Online since 19 May 2015