AbstractAutoimmune lymphoproliferative syndrome is frequently caused by mutations in genes involved in the Fas death receptor pathway, but for 20–30% of patients the genetic defect is unknown. We observed that treatment of healthy T cells with interleukin-12 induces upregulation of Fas ligand and Fas ligand-dependent apoptosis. Consistently, interleukin-12 could not induce apoptosis in Fas ligand-deficient T cells from patients with autoimmune lymphoproliferative syndrome. We hypothesized that defects in the interleukin-12 signaling pathway may cause a similar phenotype as that caused by mutations of the Fas ligand gene. To test this, we analyzed 20 patients with autoimmune lymphoproliferative syndrome of unknown cause by whole-exome sequencing. We identified a homozygous nonsense mutation (c.698G>A, p.R212*) in the interleukin-12/interleukin-23 receptor-component IL12RB1 in one of these patients. The mutation led to IL12RB1 protein truncation and loss of cell surface expression. Interleukin-12 and -23 signaling was completely abrogated as demonstrated by deficient STAT4 phosphorylation and interferon γ production. Interleukin-12-mediated expression of membrane-bound and soluble Fas ligand was lacking and basal expression was much lower than in healthy controls. The patient presented with the classical symptoms of autoimmune lymphoproliferative syndrome: chronic non-malignant, non-infectious lymphadenopathy, splenomegaly, hepatomegaly, elevated numbers of double-negative T cells, autoimmune cytopenias, and increased levels of vitamin B12 and interleukin-10. Sanger sequencing and whole-exome sequencing excluded the presence of germline or somatic mutations in genes known to be associated with the autoimmune lymphoproliferative syndrome. Our data suggest that deficient regulation of Fas ligand expression by regulators such as the interleukin-12 signaling pathway may be an alternative cause of autoimmune lymphoproliferative syndrome-like disease.
The autoimmune lymphoproliferative syndrome (ALPS, Canale-Smith syndrome) of early childhood21 is caused by disturbance of apoptotic signaling via the Fas death receptor pathway which primarily compromises lymphocyte homeostasis.43 Fas is a member of the tumor necrosis factor receptor superfamily. At the cell surface Fas is activated upon binding of its specific ligand (Fas ligand, FasL). This triggers the intracellular activation of caspase-8 and -10 to start a proteolytic cascade resulting in cell death.5 Due to deficient apoptosis, T lymphocytes are inefficiently cleared resulting in chronic lymphadenopathy, hepatosplenomegaly, autoimmune cytopenias, and elevated numbers of terminally differentiated, activated, otherwise rare double-negative T cells (DNT cells: CD3, TCRα/β,CD4CD8). Malignancies, especially B-cell lymphomas, may develop later in life.6
ALPS is a genetically heterogeneous disease. Most patients harbor heterozygous, autosomal dominant or recessive FAS germline mutations (ALPS-FAS7). Ninety-seven unique mutations are registered in the database of ALPS mutations at the National Institute of Allergy and Infectious Disease, www.niaid.nih.gov). However, somatic FAS mutations have also been reported (ALPS-sFAS).1186 Homozygous or compound heterozygous FAS mutations result in a clinically more severe phenotype. Less frequently, FASLG mutations (ALPS-FASLG)1612 or CASP10 mutations (ALPS-CASP10)17 have been detected. Similar symptoms are caused by mutations in CASP8 (caspase-8 deficiency state), KRAS or NRAS (RAS-associated ALPS-like disease). These cases are not classified as ALPS, because caspase-8 deficiency state is additionally characterized by disturbed T-cell activation and immunodeficiency and RAS-associated ALPS-like disease by monocytosis.2118 For 20–30% of patients with the clinical picture of ALPS, however, the genetic cause is still unknown (termed ALPS-U cases).2
It is plausible that Fas pathway regulating factors may present novel candidates causing ALPS and potential drug targets. For instance, forced expression of the Fas regulating miR-146a caused an immune disorder similar to ALPS in transgenic mice.22 One factor known to regulate expression of both Fas and FasL is interleukin-12 (IL12).3023 This cytokine mediates its effects via binding to a heterodimeric receptor composed of the IL12 receptors β1 (IL12RB1) and β2 (IL12RB2) and subsequent activation of JAK/STAT signaling.31 The IL12 receptor is mainly expressed on T lymphocytes and natural killer (NK) cells. IL12RB1 deficiency is associated with Mendelian susceptibility to mycobacterial diseases.3532 These diseases predispose affected individuals to mycobacterial infections (tuberculosis) due to disturbance of IL12/IL23/IFNγ signaling. IL12RB1 also associates with IL23R to form the IL23 receptor. Phagocytic cells release both IL12 and IL23 in response to non-viral infections to induce the secretion of interferon (IFN)γ by T and NK cells. This in turn stimulates phagocytes to eliminate intracellular pathogens and activation of IFNγ–secreting T helper cells. The IL12 signaling pathway is known to regulate FasL expression on activated T cells and knockout of IL12RB2 predisposes mice to spontaneous autoimmunity, lymphoproliferation and B-cell malignancies.36 In the present study we identified a patient with a classical ALPS phenotype that was associated with a truncating nonsense mutation in IL12RB1 and loss of IL12/IL23-mediated signaling.
Study cohorts and DNA isolation
Twenty-six ALPS patients, relatives and healthy controls were enrolled in the study. Written informed consent was obtained from all participants. Experiments were approved by the Ethical Review Boards of Hadassah, the Israeli Ministry of Health and the local Ethics committee of the University of Düsseldorf. Mononuclear cells were derived from peripheral blood by Ficoll (Biochrom, Berlin, Germany) density centrifugation. DNT cells were magnetically selected employing the double-negative T-cell isolation kit (Miltenyi, Bergisch-Gladbach, Germany). Genomic DNA was isolated from whole blood or DNT cells using the DNA blood kit (Qiagen, Hilden, Germany).
Whole-exome sequencing and data analysis
After exclusion of mutations in known ALPS-associated genes by targeted Sanger sequencing (Online Supplementary Methods, Online Supplementary Table S1) whole-exome sequencing was carried out as described elsewhere.37 In brief, sequencing libraries of 350 bp fragments were generated from sheared genomic DNA. Exome capture was performed using the SeqCap EZ Exome Library 2.0 kit (Roche/Nimblegen, Madison, WI, USA). One hundred base-pair, single-read sequencing was performed on a HiSeq2000 (Illumina, San Diego, CA, USA).
Sequencing data were aligned against the human reference genome hg19 (GRCh37, statistics provided in Online Supplementary Table S2) and converted using Samtools.38 Variation calls were obtained employing GATK, HapMap, OmniArray and dbSNP134 datasets (The Broad Institute, Cambridge, MA, USA).39 Single nucleotide variations, small insertions and deletions were annotated using Variant Effect Predictor40 (based on Ensemble database v70). Variations were imported into a proprietary MySQL database driven workbench (termed Single Nucleotide Polymorphism Database, SNuPy). STRING 9.141 was used to identify high confidence (≥0.900) Fas pathway interaction partners (Online Supplementary Table S3).
Primary T-cell culture
Primary T cells were cultured in RPMI1640 (Life Technologies, Darmstadt, Germany) and Panserin 401 (PAN-Biotech, Aidenbach, Germany) mixed 1:1, supplemented with 10% fetal calf serum, 100 μg gentamycin (Life Technologies) and 30 U/mL IL2 (Miltenyi). They were activated with 7 μg/mL phytohemagglutinin (Life Technologies) for 4 days.
Immunophenotyping and enzyme-linked immunosorbent assays
DNT cells in peripheral blood were measured using a FACSCalibur equipped with CellQuestPro software (Becton Dickinson, BD, Heidelberg, Germany) employing anti-CD3, anti-TCRαβ (both from BD), anti-CD4 and anti-CD8 (both from Miltenyi) antibodies. Immunophenotyping was performed using: anti-B220, anti-HLA-DR, anti-CD27, anti-CD19, anti-CD25 (all from BD) and anti-CD45R (Beckman Coulter, Krefeld, Germany). Expression of Fas, FasL and IL12RB1 was measured using anti-CD95 (BD), anti-CD178/FasL (Miltenyi) and anti-CD212 antibodies (BD). FasL, IL10 and IFNγ levels in plasma and cell culture supernatants of activated T cells were measured by enzyme-linked immunosorbent assays (R&D-Systems, Wiesbaden, Germany) employing an Infinite M200 microplate reader equipped with Magellan software (Tecan, Maennedorf, Switzerland). T cells were stimulated with IL12, IL23 and IL2/IL27 (Miltenyi) as indicated.
Measurement of apoptosis
Activated primary T cells were stimulated with recombinant SuperFasL (100 ng/mL, Enzo Life Sciences, Loerrach, Germany), 1 μM staurosporine (LC Laboratories, Woburn, MA, USA), IL12 (50–200 ng/mL, Miltenyi) or left untreated. After the indicated time apoptosis was measured by annexinV-FITC (BD) and propidium iodide (Sigma-Aldrich, St. Louis, MO, USA) staining and flow cytometry. (Further methods in the Online Supplementary Material).
Interleukin-12 induces upregulation of FasL and FasL-dependent apoptosis in healthy T cells, whereas FasL-deficient T cells from patients with autoimmune lymphoproliferative syndrome lack this response
Of 26 analyzed ALPS cases, 20 had no known ALPS-associated mutation. Four patients harbored heterozygous germline mutations in the Fas receptor gene. Two siblings had a homozygous truncating FASLG mutation (g.172628545insT, p.P69Afs*75) that led to loss of FasL surface expression (Figure 1A).16 Heterozygous carriers of this mutation showed a similar expression of FasL as healthy controls. In response to prolonged IL12 treatment healthy T cells upregulated FasL (Figure 1B) and died apoptotically (Figure 1C). In spite of normal expression of IL12 receptor components (Online Supplementary Figure S1 and data not shown) this response was completely lacking in the two individuals harboring the g.172628545insT, p.P69Afs*75 mutation indicating that IL12 induces apoptosis via FasL. Downstream of the Fas receptor these patients and the heterozygous carrier had a functional apoptotic pathway as could be demonstrated by the response of their primary T cells in vitro to application of recombinant FasL to the cell culture medium (Figure 1D). These results suggest that IL12 induces FasL-dependent apoptosis and that T cells deficient in FasL expression or IL12 signaling may be protected against this physiological apoptosis trigger.
Identification of a homozygous c.698G>A, p.R212* mutation in the IL12RB1 gene
To analyze whether mutations in the IL12 pathways or related genes may cause a phenotype similar to ALPS, we sequenced the exomes of the remaining 20 ALPS-U patients who had classical ALPS symptoms without a known genetic cause, and their relatives. Sanger sequencing of all exons and exon/intron boundaries of FAS, FASLG and CASP10 was used to exclude classical disease-causing germline or somatic mutations.
By whole-exome sequencing we identified an IL12RB1 mutation in one of the ALPS families. A KEGG-based protein interaction analysis interface of our in-house developed proprietary MySQL database driven workbench (termed Single Nucleotide Polymorphism Database, SNuPy) gave this candidate disease-causing mutation highest priority because of its predicted interaction with FasL (Figure 2A, Online Supplementary Figure S2). None of the other six candidate genes derived by our sequencing data filter strategy interacted with FasL, Fas, Caspase-10 or other immediate components of the signaling cascade. STRING 9.141 was used to identify high confidence (≥0.900) interaction partners of the Fas pathway.
The mutation on chromosome 19:18186625 corresponded to c.698G>A, p.R212* of IL12RB1 and led to a stop codon gain and premature truncation of the receptor component in its extracellular domain (Online Supplementary Tables S4 and S5, Figure 2A). Sanger sequencing of IL12RB1 revealed that parents and siblings were heterozygous mutation carriers, whereas the patient was homozygous (Figure 2B, C). This mutation was not observed previously in the 1000 Genomes, HapMap, Exome Variant Server (NHLBI GO Exome Sequencing Project, Seattle WA; http://evs.gs.washington.edu/EVS/) data sets or in our in-house database of more than 300 whole-exome data sets.
As the mutated sequence seemed to encode a truncated protein that lacks the transmembrane domain necessary for membrane anchorage, we carried out FACS analyses of the patient’s lymphocytes to test for IL12RB1 expression on the cell surface. To this end, primary lymphocytes from the patient and healthy individuals were stimulated for 4 days with phytohemagglutinin/IL2. Whereas lymphocytes from healthy individuals upregulated IL12RB1 surface expression upon activation, IL12RB1 remained absent in the patient’s lymphocytes (Figure 3A). Similar results were gained employing activated T lymphocytes from the patient and healthy controls immortalized by Herpes virus saimirii (Online Supplementary Figure S3). Expression of the IL12 receptor component IL12RB2 and the IL23 receptor component IL23R was unaffected by the mutation of their heterodimerization partner IL12RB1 and was upregulated by phytohemagglutinin activation in both wild-type and IL12RB1 mutant cells (Online Supplementary Figure S4). To confirm the lack of full-length IL12RB1 expression we performed immunoblot analysis employing an antibody directed against the C-terminal region of IL12RB1. Immortalized T lymphocytes from the patient and healthy controls were lysed and western blot analysis carried out. Expression was further compared to that of freshly isolated donor lymphocytes as well as lymphocyte cell lines. Full-length IL12RB1 expression was absent from the cells derived from the patient (Figure 3B and data not shown).
The homozygous c.698G>A, p.R212* mutation in the IL12RB1 gene was associated with an autoimmune lymphoploliferative syndrome-like phenotype
The male patient harboring the homozygous IL12RB1 c.698G>A, p.R212* mutation originated from a consanguineous family of Palestinian descent. He was referred in 1996 at the age of 4 years because of the suspicion of lymphoma. In the follow up of this patient for more than 16 years he presented with classical clinical features for the diagnosis of ALPS (Table 1, Figure 4A). The two criteria required to diagnose ALPS – (i) chronic non-malignant, non-infectious lymphadenopathy and splenomegaly and (ii) elevation of the number of DNT cells – were both fulfilled. DNT cells were persistently increased (Table 1, Figure 4B). In addition, the patient exhibited typical secondary characteristics such as hepatomegaly, autoimmune cytopenias (hemolytic anemia) with polyclonal hypergammaglobulinemia, and persistently elevated levels of vitamin B12 and IL10. He had one short episode of Salmonella bacteria group B infection at the age of 11 that did not recur. No indication of active infections by mycoplasma or viruses (Epstein-Barr virus, cytomegalovirus, human immunodeficiency virus, hepatitis B and C viruses) was apparent.
The heterozygous parents and siblings appeared clinically normal, although immune phenotyping revealed increased DNT cell counts in two of them (Table 2).
In vitro the apoptotic response of the patient’s lymphocytes to treatment with recombinant FasL and a classical apoptosis-inducing agent (staurosporine) was similar to that of age- and gender-matched healthy blood donors [FasL-induced apoptosis: 58% ± 5% (patient), 57% ± 4% (healthy control); staurosporine-induced apoptosis: 86% ± 6% (patient), 86% ± 7% (healthy control)]. This demon strated functional apoptotic signaling downstream of the Fas receptor (Figure 4C) and indicated a FasL or related defect.
To analyze whether the defect in IL12RB1 affects FasL signaling, we first tested protein expression of FasL. Activation and expansion of T cells usually leads to upregulation of Fas signaling pathway components. However, in the absence of IL12RB1 expression the patient’s T lymphocytes showed a significantly lower expression of both membrane-bound and soluble FasL protein compared to that of healthy controls (Figure 4D, E and Online Supplementary Figure S5).
The IL12RB1 c.698G>A, p.R212* mutation abrogates responsiveness of T cells to interleukin-12
To test whether lack of IL12RB1 expression affects IL12 signaling we analyzed phosphorylation of STAT4, a crucial downstream component of the pathway (Figure 5). To this end, we incubated activated T lymphocytes from the patient and a healthy control with or without IL12 for up to 72 h. Immunoblot analyses of total and phosphorylated STAT4 protein demonstrated a relative increase of phosphorylated STAT4 in the healthy control in response to IL12. In contrast, this response was completely absent in the patient’s lymphocytes indicating deficient IL12 signaling.
STAT4 activation eventually leads to transcription and production of IFNγ. To test whether this is deficient in the patient we measured the induction of IFNG transcription by quantitative real-time polymerase chain reaction after 24 and 48 h of treatment with IL12 (Figure 6A). Whereas the wild-type control rapidly and strongly upregulated IFNG by about 500 fold, there was no response in the IL12RB1 c.698G>A, p.R212* mutated cells. This could be confirmed on the protein level employing enzyme-linked immunosorbent assays (Figure 6B). The cells were stimulated with IL12, IL23 or IL2/IL27. In contrast to wild-type T cells, there was no response of the IL12RB1 c.698G>A, p.R212* mutated cells to treatment with either IL12 or IL23. An upregulation of IFNγ was only detectable after treatment with IL27, which uses a different receptor. Similarly, FASLG mRNA levels analyzed by real-time polymerase chain reaction (Figure 6C) and FasL protein expression analyzed by FACS (Figure 6D) were not induced in response to IL12 treatment in the IL12RB1 c.698G>A, p.R212* mutated cells, in contrast to the wild-type control.
Finally, we tested the responsiveness of the patient’s primary lymphocytes to apoptosis mediated by prolonged IL12 treatment (Figure 6E). Activated T cells were treated with IL12 for 3 days. Specific apoptosis, measured by annexin V-FITC staining, was induced upon incubation with IL12 in the healthy controls, but not in the patient’s cells.
Although ALPS is frequently caused by mutations in known genes, such as FAS, FASLG or CASP10, in 20–30% of cases the defect is still unknown. It is highly likely that defects in or overexpression of regulators of these genes such as miR-146a22 could result in an ALPS-like phenotype and account for a not yet defined percentage of ALPS-U cases. In the present study we identified an IL12RB1 mutation and the IL12 signaling pathway as such an alternative cause of an ALPS-like phenotype through regulation of FasL expression. Previously it was shown that activation of T and NK cells by IL12 results in upregulation of FasL.42282623 For instance, Yu et al. showed that dendritic cell-derived IL12 is involved in upregulation of FasL on NK cells leading to cell death.25 Moreover, in the absence of antigen, IL12 induces apoptosis of T cells via upregulation of FasL which can be blocked by anti-FasL antibodies.26 In line with this, we found that primary human T cells deficient in FasL expression were resistant to apoptosis induced by IL12. In vivo models demonstrated that IL12 induces apoptosis of CD8 tumor-resident T cells via FasL and showed that IFNγ was necessary for this effect.42 IL12 also regulates Fas expression. Zhou et al. showed that IL12 specifically induces Fas promoter activity in breast carcinoma, osteosarcoma and Ewing tumor cells.29 IL12 treatment stimulated nuclear factor κB, and the κB-Sp1 motif (−195 to −286) in the Fas promoter sequence was essential for the activation of Fas. Lafleur et al. demonstrated that IL12 and IL12 gene transfer upregulates Fas expression on osteosarcoma and breast cancer cells.30
Consistently, we identified a homozygous stop mutation that led to loss of cell surface expression of the IL12/IL23 receptor component IL12RB1 in a patient presenting with classical ALPS symptoms in the absence of germline or somatic mutations in known ALPS genes. The patient presented with chronic non-malignant, non-infectious lymphadenopathy, splenomegaly, hepatomegaly, persistent elevation of DNT cell counts, autoimmune cytopenias with polyclonal hypergammaglobulinemia, and persistently increased levels of vitamin B12 and IL10.
It might be reasoned that the observed autoimmunity and lymphoproliferation are likely a side-effect of recurrent infections, because IL12RB1 mutations have previously been associated with a predisposition to mycobacterial infections. However, the patient experienced only one non-recurrent episode of infection with Salmonella in 16 years of follow-up arguing against a secondary effect. Consistently, it was recently demonstrated, employing an IL12RB2 knockout mice model, that lack of IL12 signaling predisposes to spontaneous lymphoproliferation, autoimmunity and B-cell lymphoma.36 This phenotype was not caused by infections, because the mice were kept under pathogen-free conditions. However, infections are not an uncommon finding in ALPS patients especially after splenectomy6 and infections by Salmonella spp. and Klebsiella pneumoniae have also been observed in a FasL-deficient patient.39 Another case of ALPS-like syndrome with mycobacterial infection was reported.43 Interestingly, Guerra et al. demonstrated that IL12-mediated upregulation of FasL and CD40L was involved in the control of mycobacterium tuberculosis growth by activated NK cells.44 Deficiency in both IL12 and FasL expression can, therefore, contribute to susceptibility to infection. Previous analysis of patients with IL12RB1 mutations demonstrated deficient IL12/JAK/STAT signaling (as could be confirmed for the patient analyzed here), lack of resulting IFNγ production by T and NK cells as well as deficient IL23 signaling and low levels of IL17-producing T cells.45 A similar phenotype is described for targeted IL12RB1 knockout mice.46 In humans the clinical penetrance of IL12RB1 mutations varies.
Heterozygous human carriers appear clinically normal with normal IL12/IL23 signaling and IFNγ production.34 In two individuals of the analyzed family DNT cell numbers were slightly increased indicating possible effects of the heterozygous mutation on ALPS characteristics. We also detected increased numbers of DNT cells (14% of gated CD3 cells) in a patient with a complete loss of IFNγR2 expression; however, in this case it could not be ruled out that the increase was a response to frequent and recurrent infections (data not shown).
Our study demonstrates for the first time that loss of IL12RB1 expression in a patient leads to reduced upregulation of FasL and loss of the apoptotic response of T cells to prolonged treatment with IL12. In addition, the general level of FasL expression in activated T cells and the level of secreted FasL in the plasma or cell culture supernatant were much lower in the patient than in controls. Lower levels of FasL expression in the patient are probably attributable to a lack of IFNγ, because transcription of the FASLG promoter is positively regulated by the interferon-regulatory factors IRF-1 and IRF-2.47 Consistently, it has been reported that mononuclear cells from IL12RB1-deficient patients produce significantly lower amounts of IFNγ in response to mitogens or antigens3332 and low IFNγ production is a common trait of all reported knockout mice models that are deficient in IL12RB1, IL12RB2 or IL12 (p40 or p35).48
IL12 is known as a factor that can stimulate growth and function of T cells and the differentiation of naive T cells into Th1 cells. However, prolonged stimulation of T cells with IL12 leads to apoptosis and stimulation of T cells with IL12 during activation enhances the tendency to undergo Fas-mediated activation induced cell death due to upregulation of FasL and downregulation of the inhibitor FLIPs.27 Therefore, similar to defective Fas/FasL signaling, absence of IL12 signaling could lead to decreased death of T cells and accumulation of autoreactive T cells. In addition, it has been shown that low levels of IL12 drive the differentiation of activated T cells to long-lived self-renewing memory CD8 T cells rather than to short-lived effector cells when acute infections resolve.49 This is dependent on IL12-controlled expression of T-bet and reflected in the phenotype of T-bet knockout mice.5049
In conclusion, our results identify IL12RB1 as a new gene and IL12 signaling as a new pathway that may underlie the pathogenesis of ALPS-like disease due to their regulatory role in FasL expression. Our data suggest that mutations in IL12RB1 may lead to different clinical phenotypes, including ALPS-like disease and Mendelian susceptibility to mycobacterial diseases. Knowledge of the genetic defect underlying an ALPS-like phenotype may thus have important implications for the choice of treatment options.
The authors would like to thank Monika Schmidt for her excellent technical assistance and colleagues from the Biomedical Research Center (BMFZ, University of Duesseldorf) for providing support and carrying out the Sanger sequencing analyses.
- ↵* PS and UF contributed equally to this manuscript.
- The online version of this article has a Supplementary Appendix.
- Authorship and DisclosuresInformation on authorship, contributions, and financial & other disclosures was provided by the authors and is available with the online version of this article at www.haematologica.org.
- Received July 30, 2014.
- Accepted June 19, 2015.
- Canale VC, Smith CH. Chronic lymphadenopathy simulating malignant lymphoma. J Pediatr. 1967; 70(6):891-899. PubMedhttps://doi.org/10.1016/S0022-3476(67)80262-2Google Scholar
- Fleisher TA, Oliveira JB. Monogenic defects in lymphocyte apoptosis. Curr Opin Allergy Clin Immunol. 2013; 12(6):609-615. Google Scholar
- Fisher GH, Rosenberg FJ, Straus SE. Dominant interfering Fas gene mutations impair apoptosis in a human autoimmune lymphoproliferative syndrome. Cell. 1995; 81(6):935-946. PubMedhttps://doi.org/10.1016/0092-8674(95)90013-6Google Scholar
- Rieux-Laucat F, Le Deist F, Hivroz C. Mutations in Fas associated with human lymphoproliferative syndrome and autoimmunity. Science. 1995; 268(5215):1347-1349. PubMedhttps://doi.org/10.1126/science.7539157Google Scholar
- Fischer U, Janicke RU, Schulze-Osthoff K. Many cuts to ruin: a comprehensive update of caspase substrates. Cell Death Differ. 2003; 10(1):76-100. PubMedhttps://doi.org/10.1038/sj.cdd.4401160Google Scholar
- Neven B, Magerus-Chatinet A, Florkin B. A survey of 90 patients with autoimmune lymphoproliferative syndrome related to TNFRSF6 mutation. Blood. 2011; 118(18):4798-4807. PubMedhttps://doi.org/10.1182/blood-2011-04-347641Google Scholar
- Oliveira JB, Bleesing JJ, Dianzani U. Revised diagnostic criteria and classification for the autoimmune lymphoproliferative syndrome (ALPS): report from the 2009 NIH International Workshop. Blood. 2010; 116(14):e35-40. PubMedhttps://doi.org/10.1182/blood-2010-04-280347Google Scholar
- Holzelova E, Vonarbourg C, Stolzenberg MC. Autoimmune lymphoproliferative syndrome with somatic Fas mutations. N Engl J Med. 2004; 351(14):1409-1418. PubMedhttps://doi.org/10.1056/NEJMoa040036Google Scholar
- Dowdell KC, Niemela JE, Price S. Somatic FAS mutations are common in patients with genetically undefined autoimmune lymphoproliferative syndrome. Blood. 2010; 115(25):5164-5169. PubMedhttps://doi.org/10.1182/blood-2010-01-263145Google Scholar
- Magerus-Chatinet A, Neven B, Stolzenberg MC. Onset of autoimmune lymphoproliferative syndrome (ALPS) in humans as a consequence of genetic defect accumulation. J Clin Invest. 2011; 121(1):106-112. PubMedhttps://doi.org/10.1172/JCI43752Google Scholar
- Lambotte O, Neven B, Galicier L. Diagnosis of autoimmune lymphoproliferative syndrome caused by FAS deficiency in adults. Haematologica. 2013; 98(3):389-392. PubMedhttps://doi.org/10.3324/haematol.2012.067488Google Scholar
- Wu J, Wilson J, He J. Fas ligand mutation in a patient with systemic lupus erythematosus and lymphoproliferative disease. J Clin Invest. 1996; 98(5):1107-1113. PubMedhttps://doi.org/10.1172/JCI118892Google Scholar
- Del-Rey M, Ruiz-Contreras J, Bosque A. A homozygous Fas ligand gene mutation in a patient causes a new type of autoimmune lymphoproliferative syndrome. Blood. 2006; 108(4):1306-1312. PubMedhttps://doi.org/10.1182/blood-2006-04-015776Google Scholar
- Bi LL, Pan G, Atkinson TP. Dominant inhibition of Fas ligand-mediated apoptosis due to a heterozygous mutation associated with autoimmune lymphoproliferative syndrome (ALPS) Type Ib. BMC Med Genet. 2007; 8:41. PubMedhttps://doi.org/10.1186/1471-2350-8-41Google Scholar
- Magerus-Chatinet A, Stolzenberg MC, Lanzarotti N. Autoimmune lymphoproliferative syndrome caused by a homozygous null FAS ligand (FASLG) mutation. J Allergy Clin Immunol. 2013; 131(2):486-490. https://doi.org/10.1016/j.jaci.2012.06.011Google Scholar
- Nabhani S, Honscheid A, Oommen PT. A novel homozygous Fas ligand mutation leads to early protein truncation, abrogation of death receptor and reverse signaling and a severe form of the autoimmune lymphoproliferative syndrome. Clin Immunol. 2014; 155(2):231-237. PubMedhttps://doi.org/10.1016/j.clim.2014.10.006Google Scholar
- Wang J, Zheng L, Lobito A. Inherited human caspase 10 mutations underlie defective lymphocyte and dendritic cell apoptosis in autoimmune lymphoproliferative syndrome type II. Cell. 1999; 98(1):47-58. PubMedhttps://doi.org/10.1016/S0092-8674(00)80605-4Google Scholar
- Chun HJ, Zheng L, Ahmad M. Pleiotropic defects in lymphocyte activation caused by caspase-8 mutations lead to human immunodeficiency. Nature. 2002; 419(6905):395-399. PubMedhttps://doi.org/10.1038/nature01063Google Scholar
- Oliveira JB, Bidere N, Niemela JE. NRAS mutation causes a human autoimmune lymphoproliferative syndrome. Proc Natl Acad Sci USA. 2007; 104(21):8953-8958. PubMedhttps://doi.org/10.1073/pnas.0702975104Google Scholar
- Niemela JE, Lu L, Fleisher TA. Somatic KRAS mutations associated with a human nonmalignant syndrome of autoimmunity and abnormal leukocyte homeostasis. Blood. 2011; 117(10):2883-2886. PubMedhttps://doi.org/10.1182/blood-2010-07-295501Google Scholar
- Takagi M, Shinoda K, Piao J. Autoimmune lymphoproliferative syndrome-like disease with somatic KRAS mutation. Blood. 2011; 117(10):2887-2890. PubMedhttps://doi.org/10.1182/blood-2010-08-301515Google Scholar
- Guo Q, Zhang J, Li J. Forced miR-146a expression causes autoimmune lymphoproliferative syndrome in mice via downregulation of Fas in germinal center B cells. Blood. 2013; 121(24):4875-4883. PubMedhttps://doi.org/10.1182/blood-2012-08-452425Google Scholar
- Mori S, Jewett A, Murakami-Mori K. The participation of the Fas-mediated cytotoxic pathway by natural killer cells is tumor-cell-dependent. Cancer Immunol Immunother. 1997; 44(5):282-290. PubMedhttps://doi.org/10.1007/s002620050384Google Scholar
- Leite-de-Moraes MC, Herbelin A, Gouarin C. Fas/Fas ligand interactions promote activation-induced cell death of NK T lymphocytes. J Immunol. 2000; 165(8):4367-4371. PubMedhttps://doi.org/10.4049/jimmunol.165.8.4367Google Scholar
- Yu Y, Hagihara M, Ando K. Enhancement of human cord blood CD34+ cell-derived NK cell cytotoxicity by dendritic cells. J Immunol. 2001; 166(3):1590-1600. PubMedhttps://doi.org/10.4049/jimmunol.166.3.1590Google Scholar
- Fan H, Walters CS, Dunston GM, Tackey R. IL-12 plays a significant role in the apoptosis of human T cells in the absence of antigenic stimulation. Cytokine. 2002; 19(3):126-137. PubMedhttps://doi.org/10.1006/cyto.2002.1958Google Scholar
- von Rossum A, Krall R, Escalante NK, Choy JC. Inflammatory cytokines determine the susceptibility of human CD8 T cells to Fas-mediated activation-induced cell death through modulation of FasL and c-FLIP(S) expression. J Biol Chem. 2011; 286(24):21137-21144. PubMedhttps://doi.org/10.1074/jbc.M110.197657Google Scholar
- Kitaura H, Nagata N, Fujimura Y. Effect of IL-12 on TNF-alpha-mediated osteoclast formation in bone marrow cells: apoptosis mediated by Fas/Fas ligand interaction. J Immunol. 2002; 169(9):4732-4738. PubMedhttps://doi.org/10.4049/jimmunol.169.9.4732Google Scholar
- Zhou Z, Lafleur EA, Koshkina NV. Interleukin-12 up-regulates Fas expression in human osteosarcoma and Ewing’s sarcoma cells by enhancing its promoter activity. Mol Cancer Res. 2005; 3(12):685-691. PubMedhttps://doi.org/10.1158/1541-7786.MCR-05-0092Google Scholar
- Lafleur EA, Jia SF, Worth LL. Interleukin (IL)-12 and IL-12 gene transfer up-regulate Fas expression in human osteosarcoma and breast cancer cells. Cancer Res. 2001; 61(10):4066-4071. PubMedGoogle Scholar
- van de Vosse E, Hoeve MA, Ottenhoff TH. Human genetics of intracellular infectious diseases: molecular and cellular immunity against mycobacteria and salmonellae. Lancet Infect Dis. 2004; 4(12):739-749. PubMedhttps://doi.org/10.1016/S1473-3099(04)01203-4Google Scholar
- Altare F, Durandy A, Lammas D. Impairment of mycobacterial immunity in human interleukin-12 receptor deficiency. Science. 1998; 280(5368):1432-1435. PubMedhttps://doi.org/10.1126/science.280.5368.1432Google Scholar
- de Jong R, Altare F, Haagen IA. Severe mycobacterial and Salmonella infections in interleukin-12 receptor-deficient patients. Science. 1998; 280(5368):1435-1438. PubMedhttps://doi.org/10.1126/science.280.5368.1435Google Scholar
- Fieschi C, Dupuis S, Catherinot E. Low penetrance, broad resistance, and favorable outcome of interleukin 12 receptor beta1 deficiency: medical and immunological implications. J Exp Med. 2003; 197(4):527-535. PubMedhttps://doi.org/10.1084/jem.20021769Google Scholar
- Fieschi C, Bosticardo M, de Beaucoudrey L. A novel form of complete IL-12/IL-23 receptor beta1 deficiency with cell surface-expressed nonfunctional receptors. Blood. 2004; 104(7):2095-2101. PubMedhttps://doi.org/10.1182/blood-2004-02-0584Google Scholar
- Airoldi I, Di Carlo E, Cocco C. Lack of Il12rb2 signaling predisposes to spontaneous autoimmunity and malignancy. Blood. 2005; 106(12):3846-3853. PubMedhttps://doi.org/10.1182/blood-2005-05-2034Google Scholar
- Chen C, Bartenhagen C, Gombert M. Next-generation-sequencing-based risk stratification and identification of new genes involved in structural and sequence variations in near haploid lymphoblastic leukemia. Genes Chromosomes Cancer. 2013; 52(6):564-579. PubMedhttps://doi.org/10.1002/gcc.22054Google Scholar
- Li H, Handsaker B, Wysoker A. The Sequence Alignment/Map format and SAMtools. Bioinformatics. 2009; 25(16):2078-2079. PubMedhttps://doi.org/10.1093/bioinformatics/btp352Google Scholar
- DePristo MA, Banks E, Poplin R. A framework for variation discovery and genotyping using next-generation DNA sequencing data. Nat Genet. 2011; 43(5):491-498. PubMedhttps://doi.org/10.1038/ng.806Google Scholar
- McLaren W, Pritchard B, Rios D. Deriving the consequences of genomic variants with the Ensembl API and SNP effect predictor. Bioinformatics. 2010; 26(16):2069-2070. PubMedhttps://doi.org/10.1093/bioinformatics/btq330Google Scholar
- Franceschini A, Szklarczyk D, Frankild S. STRING v9.1: protein-protein interaction networks, with increased coverage and integration. Nucleic Acids Res. 2013; 41(Database issue):D808-815. PubMedhttps://doi.org/10.1093/nar/gks1094Google Scholar
- Kilinc MO, Rowswell-Turner RB, Gu T. Activated CD8+ T-effector/memory cells eliminate CD4+ CD25+ Foxp3+ T-suppressor cells from tumors via FasL mediated apoptosis. J Immunol. 2009; 183(12):7656-7660. PubMedhttps://doi.org/10.4049/jimmunol.0902625Google Scholar
- Hong YH, Lee CK. Autoimmune lymphoproliferative syndrome-like syndrome presented as lupus-like syndrome with mycobacterial joint infection evolved into the lymphoma. Rheumatol Int. 2009; 29(5):569-573. PubMedhttps://doi.org/10.1007/s00296-008-0707-4Google Scholar
- Guerra C, Johal K, Morris D. Control of Mycobacterium tuberculosis growth by activated natural killer cells. Clin Exp Immunol. 2012; 168(1):142-152. PubMedhttps://doi.org/10.1111/j.1365-2249.2011.04552.xGoogle Scholar
- van de Vosse E, Haverkamp MH, Ramirez-Alejo N. IL-12Rbeta1 deficiency: mutation update and description of the IL12RB1 variation database. Hum Mutat. 2013; 34(10):1329-1339. PubMedhttps://doi.org/10.1002/humu.22380Google Scholar
- Miller HE, Robinson RT. Early control of Mycobacterium tuberculosis infection requires il12rb1 expression by rag1-dependent lineages. Infect Immun. 2012; 80(11):3828-3841. PubMedhttps://doi.org/10.1128/IAI.00426-12Google Scholar
- Chow WA, Fang JJ, Yee JK. The IFN regulatory factor family participates in regulation of Fas ligand gene expression in T cells. J Immunol. 2000; 164(7):3512-3518. PubMedhttps://doi.org/10.4049/jimmunol.164.7.3512Google Scholar
- Wu C, Wang X, Gadina M. J. IL-12 receptor beta 2 (IL-12R beta 2)-deficient mice are defective in IL-12-mediated signaling despite the presence of high affinity IL-12 binding sites. J Immunol. 2000; 165(11):6221-6228. PubMedhttps://doi.org/10.4049/jimmunol.165.11.6221Google Scholar
- Joshi NS, Cui W, Chandele A. Inflammation directs memory precursor and short-lived effector CD8(+) T cell fates via the graded expression of T-bet transcription factor. Immunity. 2007; 27(2):281-295. PubMedhttps://doi.org/10.1016/j.immuni.2007.07.010Google Scholar
- Takemoto N, Intlekofer AM, Northrup JT. Cutting edge: IL-12 inversely regulates T-bet and eomesodermin expression during pathogen-induced CD8+ T cell differentiation. J Immunol. 2006; 177(11):7515-7519. PubMedhttps://doi.org/10.4049/jimmunol.177.11.7515Google Scholar