Citrulline and Monocyte-Derived Macrophage Reactivity before Conditioning Predict Acute Graft-versus-Host Disease

Abstract

During conditioning, intestinal damage induces microbial translocation which primes macrophage reactivity and leads to donor-derived T cell stimulation. Little is known about the role of intestinal health and macrophage reactivity before conditioning in the development of acute graft-versus-host disease (aGVHD) in patients undergoing allogeneic hematopoietic cell transplantation (allo-HCT). We assessed (1) citrulline, a surrogate marker of functional enterocyte mass and (2) circulating monocyte-derived macrophage reactivity, before allo-HCT. Forty-seven consecutive patients were prospectively included. Citrulline levels from blood samples withdrawn 30 days before transplantation were assessed using liquid chromatography combined with mass spectrometry. Monocyte-derived macrophages were isolated and incubated with 5 pathogen-associated molecular patterns: lipopolysaccharide, PamCSK4, flagellin, muramyl dipeptide, and curdlan. Multiplex fluorescent immunoassay on culture supernatant assessed levels of TNF-α, IL-1β, IL-6, and IL-10 in each condition. Citrulline and cytokine levels were analyzed relatively to aGVHD onset within 100 days after transplantation. Citrulline levels were lower in the aGVHD group (n = 20) than in the no-aGVHD group (n = 27) (P = .005). Conversely, IL-6 and IL-10 were greater in aGVHD group, especially after curdlan stimulation (P = .005 and P = .012). Citrulline levels ≤20 µmol/L, IL-6 ≥ 332 pg/mL, and IL-10 ≥ 90 pg/mL were associated with aGVHD development (log-rank test, P = .002, P = .041, and P < .0001, respectively). In multivariate analysis, IL-10 ≥ 90 pg/mL, myeloablative conditioning, and citrulline ≤20 µmol/L remained independent factors of aGVHD development (hazard ratio [HR], 8.18, P = .0003; HR, 4.28, P = .006; and HR, 4.43, P = .01, respectively). Preconditioning citrulline and monocyte-derived macrophage reactivity are objective surrogate markers suitable to identify patients at risk of developing aGVHD. This work highlights the influence of preconditioning status in aGVHD development.

Impact and consequences of intensive chemotherapy on intestinal barrier and microbiota in acute myeloid leukemia: the role of mucosal strengthening

“…These two parameters reflect persistent subclinical damage secondary to high-dose chemotherapies delivered during a 7 + 3 regimen. 37 In addition, the interest of citrulline level as a strong predictive factor of GvHD before an allo-SCT procedure was recently confirmed. 38 In our experience, citrulline level below 26 µmol/L before an allo-SCT constitutes an independent risk factor of severe gastrointestinal GvHD.…”

“…However, at baseline, citrulline levels were higher in the Tg (76 [68-83] μmol/L) than in the Wt group (71 [63-78] μmol/L; p = .0017). Citrulline levels reached a nadir averaging at d + 1 in both groups but rose faster in Tg mice (44 [39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55] μmol/L vs. 39 [31][32][33][34][35][36][37][38][39][40][41][42] μmol/L; p = .046) at d + 3 (Figure 5c). In the latter, tracking of the GFPtagged transgene by confocal microscopy showed a transient significant decrease of fluorescence at d + 1 that progressively returned to normal value at d + 5 (Figure 5d and e).…”

High Rates of Positive Severe Combined Immunodeficiency Screening Among Newborns with Severe Intestinal Failure

“…25,26 Lower serum citrulline 1 month prior to allogeneic hematopoietic cell transplantation was associated with significantly increased risk for the development of graft-vs-host-disease. 27 These risks have generally been attributed to the phenomenon of bacterial translocation due to loss of intestinal barrier function, 26,28 but there has been little exploration of the possibility that hypocitrullinemia itself may adversely affect the immune system. The link between hypocitrullinemia and T-cell lymphopenia among infants with intestinal failure is a preliminary hypothesis, but deserves further investigation and is a potential therapeutic target.…”

Brazilian Nutritional Consensus in Hematopoietic Stem Cell Transplantation: Graft- versus -host disease

“…(67,68) Such findings were also described among patients with intestinal GVHD. (69) This amino acid has also shown to be promising in predicting GVHD, (70) although more literature data are needed for its use in clinical practice.…”