Immune Gene Variant and Raised IL-27 Levels Linked to Neonatal Cholestasis Risk

A genetic variant in the immune signaling molecule interleukin-27 appears to substantially raise the odds that an infant will develop neonatal cholestasis, a rare but serious liver condition in which bile builds up inside the liver during the first months of life. In a case-control study conducted at the National Liver Institute of Menoufia University in Egypt, researchers found that the T allele of the IL-27 T4730C polymorphism, also known as rs181206, was far more common among affected infants than among healthy controls, and that infants carrying the TT genotype faced a markedly elevated risk. Alongside the genetic finding, the team measured significantly higher circulating levels of IL-27 protein in the blood of cholestatic infants compared with controls, suggesting that both the gene and its protein product merit closer scrutiny as potential markers of the disease.

Neonatal cholestasis is defined by the liver retaining bile due to abnormalities in bile production or flow during the first three months of life, and it affects roughly one in every 2,500 live births. Its most commonly recognized cause is biliary atresia, a destructive obstruction of the bile ducts that accounts for an estimated 35 to 41 percent of cases. Because early diagnosis is critical, since prompt treatment for some specific causes can prolong native liver survival and be lifesaving, researchers have been searching for molecular clues that could sharpen the diagnostic workup, which currently relies on a combination of clinical observations, laboratory analysis, radiographic evidence and, ultimately, specialist judgment.

The rationale for examining IL-27 rests on growing evidence that the immune system participates in the bile duct injury seen in cholestatic infants. Patients with biliary atresia show increased expression of lymphocyte activation and proliferation in their portal veins, and numerous single-nucleotide polymorphisms in genes such as ADD3, EFEMP1, MMP7 and ARF6 have already been implicated in the condition’s pathophysiology. IL-27, a member of the IL-12 cytokine family formed by the combination of the EBI3 and IL-27p28 subunits, signals through a receptor complex composed of gp130 and IL-27Ra and exerts both immunostimulatory and inhibitory effects on a wide range of immune cells. It has also been shown to exert interferon-gamma-like functions in hepatocytes and hepatoma cells, contributing to the antiviral response in these cells.

The T4730C variant, located in the IL27p28 gene, has previously been studied in a variety of autoimmune diseases as well as in hepatocellular, esophageal and colorectal tumors. Research indicates that this polymorphism creates binding regions for transcription factors that control alternative splicing, such as splicing factor 2. According to the study team, no previous work had focused on the connection between IL-27 and liver disease in the context of neonatal cholestasis, leaving the relationship between rs181206 and NC susceptibility poorly understood and motivating the present investigation as a search for a possible novel diagnostic biomarker.

The study enrolled 61 infants in total: 41 patients with confirmed neonatal cholestasis, subdivided into 20 with biliary atresia and 21 with non-BA cholestasis, plus 20 healthy controls. Participants were recruited from the Pediatric Hepatology Department’s inpatient and outpatient clinics, and infants with serious congenital diseases, other related hepatobiliary illnesses, prior liver transplantation or a family history of autoimmune, liver or neonatal cholestasis diseases were excluded. The diagnosis of neonatal cholestasis was verified through a cholestasis workup combining laboratory-based analysis, radiographic evidence and clinical observations, with pediatric hepatologists and pediatric surgeons collaborating on each final diagnosis. Of 67 infants initially screened, six were excluded, two because their families declined consent and four because they did not meet the inclusion criteria.

Genotyping was performed on DNA extracted from three milliliters of EDTA-anticoagulated peripheral blood using a pre-designed TaqMan allelic discrimination assay, which relies on fluorescent allele-specific probes to distinguish the T and C alleles of rs181206, with C as the minor allele. Serum IL-27 concentrations were measured with a double antibody sandwich enzyme-linked immunosorbent assay with an analytical range of 6.5 to 2,000 picograms per milliliter and a sensitivity of 5.521 picograms per milliliter. Statistical analysis employed chi-squared and Fisher’s exact tests for categorical comparisons, non-parametric tests for quantitative variables, and multivariable binary logistic regression, with model fit assessed by the Hosmer-Lemeshow test.

The genetic results were striking. The frequency of the T allele was 98.8 percent among neonatal cholestasis patients versus 60 percent among controls, a difference that reached statistical significance with a P value of 0.002. In the dominant genetic model, carriers of the TT genotype had a 17.14-fold increased odds of developing neonatal cholestasis, with an odds ratio of 17.14 and a 95 percent confidence interval spanning 1.89 to 155.14 and a P value of 0.004. In multivariable logistic regression adjusting for age and gender, carriers of the T allele in the TC or TT genotypes had significantly higher odds of the outcome compared with the CC genotype, with an adjusted odds ratio of 20.61 and a 95 percent confidence interval of 2.17 to 195.91 and a P value of 0.008. Age was independently associated with the outcome, with an adjusted odds ratio of 1.02 per day, while gender was not. Genotype distributions in controls did not significantly deviate from Hardy-Weinberg equilibrium, and notably, the genotypic distribution and allelic frequencies did not differ significantly between the biliary atresia and non-BA patient subgroups.

The protein measurements told a complementary story. Serum IL-27 levels were significantly higher in infants with neonatal cholestasis, averaging 98.180 plus or minus 34.96 in the biliary atresia group and 100.757 plus or minus 46.42 in the non-BA group, compared with 76.070 plus or minus 5.8650 in controls. However, the mean levels did not differ significantly between the BA and non-BA subgroups, and serum IL-27 levels showed no statistically significant variation across the different genotypes, a result the authors described as unexpected. They propose several possible explanations: the variant may primarily affect IL-27 function at the cellular signaling level rather than altering protein production or stability, consistent with reports that rs181206 is a missense mutation in the exon region; an epistatic haplotype effect involving a promoter-region SNP may reduce IL-27 expression; or the modest sample size may have limited detection of small effect sizes.

To gauge diagnostic potential, the team performed receiver operating characteristic curve analysis of serum IL-27. The area under the curve was 0.726 for neonatal cholestasis overall, with a 95 percent confidence interval of 0.600 to 0.851; 0.690 for biliary atresia, with a confidence interval of 0.508 to 0.872; and 0.760 for non-BA cholestasis, with a confidence interval of 0.606 to 0.913. A cutoff of 76.67 picograms per milliliter yielded a sensitivity of 70.7 percent and a specificity of 60 percent for neonatal cholestasis, while cutoffs of 77.35 and 76.75 picograms per milliliter gave sensitivities of 65 percent and 76.2 percent, respectively, each with 60 percent specificity, for BA and non-BA. The authors suggest these levels could serve diagnostic purposes but emphasize that validation in larger, independent cohorts, particularly in combination with additional biomarkers, is needed.

The findings sit within a broader and sometimes inconsistent literature on IL-27 variants in liver disease. Previous studies have linked other IL-27 polymorphisms, including rs4788084 in the promoter and rs153109, to non-alcoholic fatty liver disease and to hepatocellular carcinoma and cirrhosis, while two earlier Egyptian studies found no correlation between rs181206 and the risk or chronicity of hepatitis B infection. The variant has been implicated in multiple sclerosis and Crohn’s disease but not in autoimmune thyroid diseases, Graves’ disease, Hashimoto’s thyroiditis or rheumatoid arthritis, suggesting that IL-27-driven pathways form part of a wider inflammatory network rather than being restricted to one organ. The authors caution that their study examined only this single polymorphism and that the restricted sample size may have led to underestimation of effects, calling for multi-center studies with larger samples to clarify how gene variants influence neonatal cholestasis across ethnicities. Demographic characteristics, including gender and age distribution, showed no significant differences between patients and controls, strengthening the case that the genetic association is not an artifact of population structure.

Subject of Research: Association between the IL-27 T4730C polymorphism, serum IL-27 levels and neonatal cholestasis risk

Article Title: Assessment of IL-27 T4730C polymorphism and its serum levels in neonatal cholestasis patients

Article References: Elmaghraby, A. S., Nagi, S. A. M., Dawoud, A. M., Khalil, M. M., Yehia, S. A., Abdelhalim, H., & Elashkar, A. E. (2026). Assessment of IL-27 T4730C polymorphism and its serum levels in neonatal cholestasis patients. Egyptian Liver Journal, 16(1), Article 69. https://doi.org/10.1186/s43066-026-00551-2

Image Credits: AI Generated

DOI: 10.1186/s43066-026-00551-2

Keywords: neonatal cholestasis, biliary atresia, IL-27, rs181206, single nucleotide polymorphism, genetic susceptibility, case-control study, biomarker, ELISA, ROC analysis, liver disease, cytokine