Introduction

Dysregulated immune-mediated angiogenesis is believed to be a crucial step in the initiation and propagation of excessive inflammatory response. It is largely mediated by Vascular Endothelial Growth Factor (VEGF-A), but there is a growing body of evidence for the role of newly discovered autoantibodies related to VEGF signaling.

Aims & Methods

The aim of the study was to determine if clinical aspects of Crohn’s disease (CD) could be defined by the antibodiome related to VEGF signaling. To this end, serum samples from 66 deeply characterized patients with clinically active CD were analyzed for the levels of VEGF-A and autoantibodies against VEGF-A, VEGF receptors VEGFR1 and VEGFR2, angiotensin II receptor type 1 (AT1R) and endothelin A receptor (ETAR).

Results

When compared to reference levels from 197 healthy controls, the levels of autoantibodies against VEGF-A, VEGFR1, VEGFR2 were significantly lower, and against AT1R were significantly higher in CD patients, separating these two cohorts with high specificity and sensitivity (AUC: 0.78, 0.91, 0.99, 0.79, respectively; p<0.0001 for all). There was no difference in anti-ETAR levels between controls and CD patients. Interestingly, for all VEGF-related autoantibodies, their levels were significantly lower in CD patients with isolated colonic disease compared to those with ileal involvement. In this respect, the levels of autoantibodies against VEGF-A, VEGFR1, VEGFR2, AT1R, and ETAR discriminated with high sensitivity and specificity colonic from non-colonic CD with AUC and p-values: 0.77, 0.72, 0.74, 0.77, 0.77 and 0.001, 0.009, 0.004, 0.001, 0.001, respectively. Also when CD patients were categorized into quartiles according to the concentration of autoantibodies, their high levels were more frequently observed in patients with ileal lesions (see table). These differences were not related to whether patients required treatment with steroids and azathioprine or not. Heatmaps representing correlations between autoantibodies revealed that in patients with the isolated colonic disease, these correlations were strongly positive (r values ranging from 0.5 to 0.9), while they were less pronounced in patients with ileal involvement (r values ranging from 0.3 to 0.9). Moreover, in patients with isolated colonic disease, C-reactive protein (CRP) levels correlated positively with the levels of VEGF-A (r=0.6) but negatively with the levels of VEGF-related autoantibodies (r values ranging from - 0.3 to - 0.4). In contrast, in patients with ileal involvement, CRP did not show any significant correlations in these respects.

Conclusion

To the best of our knowledge, this is the first demonstration that antibodiome related to VEGF signaling may represent a laboratory signature that differentiates CD patients and healthy individuals and that discriminates CD patients with colonic disease from those with ileal involvement.
These data support the concept that the patient’s immune background as represented by a set of angiogenesis-related autoantibodies may determine the extent and location of gastrointestinal inflammation.

Clinical Case Summary

Cryptosporidiosis is a gastrointestinal infection caused by the protozoan Cryptosporidium spp. It is typically self-limited in immunocompetent patients. However, in immunocompromised individuals, it can lead to moderate to severe diarrhea and significant morbidity and mortality.¹
We present the case of a 31-year-old woman with a history of Crohn’s disease in remission, who presented with a one-week history of diarrhea (up to 10 bowel movements daily), abdominal pain, and fever (38°C). Laboratory tests revealed an elevated C-reactive protein (CRP), and intestinal ultrasound showed bowel wall thickening, hyperemia and wall disruption, suggestive of an active flare. However, routine stool culture isolated Cryptosporidium, and based on her clinical background, oral paromomycin and azithromycin were initiated, resulting in complete clinical remission.
Cryptosporidiosis is a common parasitic cause of diarrhea, particularly affecting immunocompromised patients, such as those with HIV, cancer or solid organ transplants.²
Although few cases have been described in inflammatory bowel disease (IBD), the immunosuppressive state of these patients may increase the risk of infection. Diagnosing cryptosporidiosis in this population can be challenging, as stool tests detect only about 30% of cases, and the clinical presentation often mimics an IBD flare.³
Treatment is generally supportive and reserved for severe or refractory cases. Nitazoxanide is the drug of choice, and in non-responders, it can be combined with fluoroquinolones or azithromycin. In IBD patients, the decision to initiate specific antiparasitic treatment depends on the degree of immunosuppression and the clinical scenario.⁴
A clear association between IBD and cryptosporidiosis has not been established, but it is crucial to rule out opportunistic gastrointestinal infections in suspected flare-ups before starting specific therapies.
image "Bowel wall thickening, hyperemia, and disruption of the normal layer pattern."

References

(1) Janssen B, Snowden J. Cryptosporidiosis. 2023 Jul 10. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan–. PMID: 28846353.
(2) Liu B, Schnider A, DeArmond M, Banach DB, Haubrich BA. Cryptosporidiosis in individuals with inflammatory bowel disease: a scoping review protocol. BMJ Open. 2024 Oct 15;14(10):e086529. doi: 10.1136/bmjopen-2024-086529. PMID: 39414295; PMCID: PMC11481120.
(3) Ferreira J, Baden R, Magge S, Cheifetz A. Cryptosporidiosis masquerading as a Crohn's flare. Inflamm Bowel Dis. 2011 Oct;17(10):E133-4. doi: 10.1002/ibd.21811. Epub 2011 Jul 7. PMID: 21739536.
(4) Manthey MW, Ross AB, Soergel KH. Cryptosporidiosis and inflammatory bowel disease. Dig Dis Sci 1997;42:1580–6.

Introduction

Crohn’s disease (CD) is a chronic inflammatory disease of the gastrointestinal tract. Current therapies include monoclonal antibodies, such as adalimumab (ADA) and infliximab (IFX), that target the inflammatory cytokine tumor necrosis factor alpha, collectively known as anti-TNF. While it has been shown that anti-TNF is effective at inducing and maintaining remission in patients with CD, this treatment fails in up to 40% of CD patients^​. Ineffective treatment results in disease progression and complications, emphasizing the need to understand mechanisms behind non-response and to define prognostic biomarkers. We previously identified differences in the peripheral blood DNA methylome associated with response and non-response. However, it is unclear how differential methylation can affect the transcriptome.

Aims & Methods

In this study, we assembled a cohort of 58 adult CD patients that were scheduled to start ADA or IFX treatment. Response to treatment was assessed after 6-9 months based on strict combination of endoscopic (≥50% reduction SES-CD), biochemical (CRP reduction ≥50% or CRP≤5 mg/L and FCP reduction ≥50% or FCP ≤250 µg/g) and clinical criteria (≥3 point drop in HBI or HBI ≤4 without corticosteroids). Whole peripheral blood leukocytes (PBL) were collected from patients before baseline endoscopy or at first infusion/injection, and 6-9 months later. mRNA was extracted using QIAsymphony system, converted into cDNA and sequenced in a paired-end format on the Illumina NovaSeq at the Amsterdam UMC Core Facility Genomics. Differential expression (DE) analysis was carried out within the R statistical environment (v 4.3.1) using the Bioconductor package DESeq2 (v 1.40.2).

Results

Prior to the start of treatment, we identified 504 and 750 differentially expressed genes (DEGs) distinguishing responders from non-responders in ADA and IFX cohorts, respectively. While 13 genes presented response-associated differential expression for both ADA and IFX, no overall correlation was observed between response-associated differential expression profiles. However, based on canonical pathway analysis, we found that expression differed in both ADA and IFX responders and non-responders at the level of neutrophil degranulation, B-cell receptor regulation, and cell growth and differentiation.

Conclusion

Our data suggest that response to ADA and IFX can be associated to the PBL transcriptome prior to treatment. Furthermore, while the differences between responders and non-responders to ADA and IFX display limited overlap in DEGs, we observe that response-associated pathways are shared.

Clinical Case Summary

Aims: TNFα antagonists are effective therapeutic options for induction and maintenance of remission in patients with moderate to severe Crohn’s disease. However, these agents have been linked to immunogenicity and few case reports have described the onset of IgAN after such treatment.
Methods: We report the case of a 27-year-old male patient with CD who developed an Infliximab-induced IgA nephropathy.
Case Presentation: We report a man who, at the age of 16, manifested with a perianal abscess. The patient underwent ileocolonoscopy which revealed ileocolitis with histological investigations suggestive of Crohn’s disease and was treated with pos mesalamine and pos prednisolone (with tapering). Τhe patient had a poor response so he was administered a combo therapy with iv Infliximab and pos azathioprine. Four years later (monotherapy with Infliximab) the patient manifested enteropathic spondyloarthritis so he received additionally inj methotrexate with remission of the disease. After six years, being on remission, in a routine laboratory test he had hypoalbuminemia (Alb: 2,8 gr/dL), proteinuria and hematuria (hemoglobin +3 and protein +4 on dipstick). The rest lab values showed anemia (Hct: 31,50%, Hb: 11 g/dL), normal platelets and leukocytes and normal kidney function without markers of inflammation. Urine analysis demonstrated loss of 1 g of protein per day in 24-hour urine collection. Clinical examination and abdominal ultrasound were unremarkable. Kidney biopsy was performed, revealing findings consistent with IgA nephropathy (Figure). Upon the diagnosis was confirmed, Infliximab, as a potential inducer of IgAN, was discontinued and after the induction of corticosteroid therapy the patient made a remarkable recovery.
Conclusions: In the present case, the patient has been in deep remission for years therefore, Crohn’s disease alone was presumably not the cause of IgAN. Biological agent, specifically Infliximab, has been identified as the potential cause for IgAN.

References

1. Mertelj T, Smrekar N, Kojc N, Lindič J, Kovač D. IgA Nephropathy in a Patient Treated with Adalimumab. Case Rep Nephrol Dial. 2021 Jul 28;11(2):233-240. doi: 10.1159/000515585.
2. Terasaka T, Uchida HA, Umebayashi R, Tsukamoto K, Tanaka K, Kitagawa M, Sugiyama H, Tanioka H, Wada J. The possible involvement of intestine-derived IgA1: a case of IgA nephropathy associated with Crohn's disease. BMC Nephrol. 2016 Sep 5;17(1):122. doi: 10.1186/s12882-016-0344-1.
3. Bhagat Singh AK, Jeyaruban AS, Wilson GJ, Ranganathan D. Adalimumab-induced IgA nephropathy. BMJ Case Rep. 2019 Mar 31;12(3):e226442. doi: 10.1136/bcr-2018-226442.
4. Joher N, Gosset C, Guerrot D, Pillebout E, Hummel A, Boffa JJ, Faguer S, Rabant M, Higgins S, Moktefi A, Delmas Y, Karras A, Lapidus N, Amiot A, Audard V, El Karoui K. Immunoglobulin A nephropathy in association with inflammatory bowel diseases: results from a national study and systematic literature review. Nephrol Dial Transplant. 2022 Feb 25;37(3):531-539. doi: 10.1093/ndt/gfaa378.

Disclosure

Nothing to disclose.