Type 2 Interleukin-4 Receptor Signaling in Neutrophils Antagonizes Their Expansion and Migration during Infection and Inflammation

Abstract

Neutrophils are the first immune cells recruited to sites of inflammation and infection. However, patients with allergic disorders such as atopic dermatitis show a paucity of skin neutrophils and are prone to bacterial skin infections, suggesting that allergic inflammation curtails neutrophil responses. Here we have shown that the type 2 cell signature cytokine interleukin-4 (IL-4) hampers neutrophil expansion and migration by antagonizing granulocyte colony-stimulating factor (G-CSF) and chemokine receptor-mediated signals. Cutaneous bacterial infection in mice was exacerbated by IL-4 signaling and improved with IL-4 inhibition, each outcome inversely correlating with neutrophil migration to skin. Likewise, systemic bacterial infection was worsened by heightened IL-4 activity, with IL-4 restricting G-CSF-induced neutrophil expansion and migration to tissues by affecting CXCR2-CXCR4 chemokine signaling in neutrophils. These effects were dependent on IL-4 acting through type 2 IL-4 receptors on neutrophils. Thus, targeting IL-4 might be beneficial in neutropenic conditions with increased susceptibility to bacterial infections.

IL-4 receptor engagement in human neutrophils impairs their migration and extracellular trap formation

“…27 These data suggest that the IL-4R-STAT6 signaling pathway regulates neutrophils in type 2 inflammation, possibly through more rapid mechanisms than its involvement in type 2 versus type 3 immune skewing. With the hypothesis that IL-4 could directly affect neutrophils, as recently shown in mice, 28 in the present study we have investigated the expression and effect of IL-4R signaling on primary human neutrophils after stimulation with the prototypic type 2 cytokines IL-4 and IL-13.…”

“…Intracellular staining for phospho-Y705 of STAT3 (phosphorylated signal transducer and activator of transcription [pSTAT] 3; 13A3-1, BioLegend), phospho-Y694 of STAT5 (pSTAT5; SRBCZX, Thermo Fisher), and phospho-Y641 of STAT6 (pSTAT6; CHI2S4, Thermo Fisher) was performed, as previously established. 28,29 Samples were acquired and analyzed by using flow cytometry, as stated above.…”

“…Transwell migration assays were performed, as previously published. 28,31 In brief, freshly isolated neutrophils were incubated for 2 hours at 378C in 5% CO 2 with medium (RPMI 1640 containing 1% of FBS) alone or supplemented with 150 ng/mL G-CSF, IL-4, IL-13, or serum from HDs or ADs. Where indicated, neutrophils were incubated with cytokines or with serum or preincubated with rabbit anti-human IL-4Ra mAb (anti-CD124; SinoBiological, Wayne, Pa) for 1 hour before seeding into the upper chamber of a 3-mm transwell (Costar; Corning, Corning, NY).…”

IL‐4 receptor α blockade prevents sensitization and alters acute and long‐lasting effects of allergen‐specific immunotherapy of murine allergic asthma

“…Indeed, this approach resulted in an increase of IL‐4, IL‐13, and IgE as observed in patients suffering from allergic asthma . Additionally, the IL‐4M dosage was adjusted to the short serum half‐life in vivo …”

Evolution and function of interleukin-4 receptor signaling in adaptive immunity and neutrophils

“…However, there is accumulating evidence showing that IL-4-and IL-13-mediated IL-4 receptor (IL-4R) signaling in both mouse and human neutrophils inhibits their migration and effector functions in vitro and in vivo [7,8]. In a number of different mouse models including sterile inflammation, bacterial infection, helminth infestation, and rheumatoid arthritis, IL-4R signaling was shown to have an inhibitory effect on neutrophils [9][10][11][12]. Human neutrophils isolated from allergic patients, a condition dominated by the presence of IL-4 and IL-13, were less capable of migrating and producing NETs than neutrophils from healthy donors [13].…”