CTLA4 encodes cytotoxic T-lymphocyte associated protein 4 (223 aa). Inhibitory receptor acting as a major negative regulator of T-cell responses. Highest expression in Spleen (5.8 TPM) and Small Intestine Terminal Ileum (4.9 TPM).

Autoimmune lymphoproliferative syndrome due to CTLA4 haploinsufficiency is caused by mutations in the CTLA4 gene on chromosome 2.

The CTLA4 protein participates in RUNX1:CBFB:FOXP3:CTLA4 gene, Co-inhibition by CTLA4, and Co-stimulation by CD28 pathways.

CTLA4 is classified as a druggable target (Clinically Actionable, Druggable Genome, and External Side Of Plasma Membrane categories) with score 3.4.

Genetic testing for CTLA4 is available. Testing is considered confirmatory for diagnosis.

Biomarker and diagnostic research for autoimmune lymphoproliferative syndrome due to CTLA4 haploinsufficiency has been reported in the published literature.

Phenotype severity distribution: 1 very common feature, 10 common features.

Estimated prevalence: <1 in 1,000,000 (VERY_RARE).

No clinical trials have been registered for autoimmune lymphoproliferative syndrome due to CTLA4 haploinsufficiency.

34 publications have been identified in PubMed for autoimmune lymphoproliferative syndrome due to CTLA4 haploinsufficiency. Research spans Review / Meta-Analysis (28%), Basic Science / Preclinical (22%), and Diagnostic / Biomarker (16%).

Recent Publications

• Consolini R (2026). [PMID: 42123030](https://pubmed.ncbi.nlm.nih.gov/42123030/). *J Clin Med*. [Review / Meta-Analysis]

• Macken AA (2026). [PMID: 41799868](https://pubmed.ncbi.nlm.nih.gov/41799868/). *JSES Rev Rep Tech*. [Basic Science / Preclinical]

• Somfalvi-Tóth K (2026). [PMID: 41538958](https://pubmed.ncbi.nlm.nih.gov/41538958/). *The Science of the total environment*. [Review / Meta-Analysis]

• Deeb N (2026). [PMID: 41582224](https://pubmed.ncbi.nlm.nih.gov/41582224/). *Allergy, asthma, and clinical immunology : official journal of the Canadian Society of Allergy and Clinical Immunology*. [Case Report / Case Series]

• Xu S (2026). [PMID: 41501749](https://pubmed.ncbi.nlm.nih.gov/41501749/). *BMC endocrine disorders*. [Review / Meta-Analysis]

• Ariue B (2026). [PMID: 41057108](https://pubmed.ncbi.nlm.nih.gov/41057108/). *Annals of allergy, asthma &amp; immunology : official publication of the American College of Allergy, Asthma, &amp; Immunology*. [Epidemiology / Natural History]

• Nou-Howaldt M (2026). [PMID: 41643931](https://pubmed.ncbi.nlm.nih.gov/41643931/). *European journal of vascular and endovascular surgery : the official journal of the European Society for Vascular Surgery*. [Basic Science / Preclinical]

• Fort A (2026). [PMID: 41546951](https://pubmed.ncbi.nlm.nih.gov/41546951/). *Forensic science international*. [Diagnostic / Biomarker]

• Becking AL (2026). [PMID: 41994904](https://pubmed.ncbi.nlm.nih.gov/41994904/). *Eur J Haematol*. [Case Report / Case Series]

• Okuda Y (2026). [PMID: 40971131](https://pubmed.ncbi.nlm.nih.gov/40971131/). *Clinical and experimental nephrology*. [Epidemiology / Natural History]