Type 1 Interferon Gene Signature Promotes RBC Alloimmunization in a Lupus Mouse Model

Abstract

Red blood cell (RBC) transfusion exposes recipients to hundreds of unmatched minor RBC antigens. This exposure can lead to production of alloantibodies that promote clinically significant hemolytic events. Multiple studies have reported an increased frequency of RBC alloimmunization in patients with autoimmunity. However, cellular and molecular mechanisms that underlie autoimmunity-induced alloimmunization have not been reported. Patients with systemic lupus erythematosus (SLE) have a high frequency of alloimmunization and express a type 1 interferon (IFNα/β) gene signature. Thus, we utilized the pristane-induced lupus mouse model to test the hypothesis that inflammation in lupus promotes RBC alloimmunization, and to examine the potential role of IFNα/β. Intraperitoneal injection of pristane, a hydrocarbon oil, led to autoantibody production, glomerulonephritis, and pulmonary hemorrhage in wild type (WT) mice. Pristane treatment significantly induced serum IFNα and expression of multiple interferon-stimulated genes (ISGs) in peripheral blood and peritoneal fluid cells, including inflammatory macrophages. Following transfusion with allogeneic RBCs expressing the KEL glycoprotein, pristane-treated WT mice produced significantly elevated levels of anti-KEL IgM and anti-KEL IgG, compared to untreated mice. Pristane induced comparable levels of inflammatory cells and cytokines in mice lacking the IFNα/β receptor (IFNAR1 −/−) or the IFNα/β-inducing transcriptions factors (IRF3/7 −/−), compared to WT mice. However, pristane-treated IFNAR1 −/− and IRF3/7 −/− mice failed to produce ISGs and produced significantly lower levels of transfusion-induced anti-KEL IgG, compared to WT mice. Thus, pristane induction of a lupus-like phenotype promoted alloimmunization to the KEL RBC antigen in an IFNα/β-dependent manner. To our knowledge, this is the first examination of molecular mechanisms contributing to RBC alloimmunization in a model of autoimmunity. These results warrant further investigation of the role of IFNα/β in alloimmunization to other RBC antigens and the contribution of the IFNα/β gene signature to the elevated frequency of alloimmunization in patients with SLE.

Altered type 1 interferon responses in alloimmunized and nonalloimmunized patients with sickle cell disease

“…We previously reported that IFNα/β promotes alloimmunization in mouse models [8][9][10][11]. Here, we report that a cohort of adult patients with SCD expresses an IFNα/β gene signature.…”

“…Patients with systemic lupus erythematosus (SLE) have a high frequency of alloimmunization and express a type 1 interferon (IFN α / β ) gene signature defined as the production of IFN α / β and numerous ISGs [ 16 , 17 ]. Although a role for IFN α / β in RBC alloimmunization has not been investigated in any patient population, IFN α / β promotes RBC alloimmunization in a lupus mouse model [ 10 ].…”

“…In animal models and patients, inflammation in the recipient has been shown to promote alloimmunization [4][5][6][7]. Our prior studies utilizing murine transfusion models indicate that proinflammatory type 1 interferons (IFNα/β) and interferon stimulated genes (ISGs) regulate this process [8][9][10][11]. We reported that IFNα/β and ISGs, produced following treatment of murine recipients with a viral mimetic or influenza infection, are necessary for RBC alloantibody development [8,11].…”

Retention of functional mitochondria in mature red blood cells from patients with sickle cell disease

“…In particular, type 1 interferons (e.g. IFN and IFN), most commonly associated with anti‐viral immune responses, enhance RBC alloimmunization rates in murine models, 9,14 and, interestingly, increased IFN levels were reported in patients with SCD 15 . Although the mechanistic underpinnings and potential ligands, including nucleic acids, that promote IFN production in these patients are poorly understood, patients with SCD have detectable mitochondria in their mature RBCs 16,17 .…”

Innate and adaptive immunity to transfused allogenic red blood cells in mice requires MyD88

“…Our previous work demonstrated that potentially relevant NOD-like receptor (NLR) PRRs were not required for alloantibody formation, nor was the presence of the IL-1 family cytokines (IL-1 and IL-18) (13). Murine studies demonstrate that recipient exposure to various PAMPs such as Poly(I:C), CpG and influenza virus infection prior to transfusion of RBCs enhances alloimmunization to multiple alloantigens (28)(29)(30). These PAMPs are ligands for another family of PRRs, the Toll-like receptors (TLRs).…”