Lenalidomide and Pomalidomide Improve Function and Induce FcγRI/CD64 in Multiple Myeloma Neutrophils

Abstract

Background Myeloid dysfunction is an emerging hallmark of microenvironment changes occurring in multiple myeloma (MM). Our previous work showed that FcγRI/CD64 overexpression in neutrophils of newly diagnosed MM patients is associated to inferior outcomes, reduced oxidative bursts and phagocytosis, with an increased risk of bacterial infections. Pomalidomide is a novel immune-modulatory drug approved for relapsed/refractory patients (RRMM), with drug-related neutropenia as major limitation to treatment. Patients and methods Herein, we describe a prospective analysis of 51 consecutive RRMM patients treated with pomalidomide and dexamethasone (PomDex) from March 2015 through December 2016, associated with secondary prophylaxis with filgrastim (G-CSF) in case of neutrophil count <1500 cells/μL. Neutrophil function was investigated by flow cytometry, including the phagocytosis, oxidative bursts, and median fluorescence intensity of FcγRI-CD64. Controls included a group of newly diagnosed symptomatic MM (NDMM), asymptomatic (smoldering myeloma, MGUS) and healthy subjects referred to our Center in the same time-frame. Results Compared to controls, RRMM neutrophils had higher expression of FcγRI/CD64 and lower phagocytic activity and oxidative bursts. We maintained median leukocyte counts higher than 3.5· 10^9/L for 6 cycles, and median neutrophil counts higher than 1.5 · 10^9/L, with only 6 (11%) patients developing grade 3–4 infections, without pomalidomide dose reduction. After 4 cycles of PomDex, FcγRI/CD64 was further increased in neutrophils, and phagocytic activity and oxidative bursts recovered independently from filgrastim exposure and the quality of hematological responses. Similarly, in NDMM patients, lenalidomide but not bortezomib upregulated FcγRI/CD64 expression, improving phagocytic activity and oxidative bursta as tested in vitro. Conclusions Our combined biological and clinical data provide new information on the ability of pomalidomide and lenalidomide to modulate the functional activity of neutrophils, despite their chronic activation due to FcγRI/CD64 overexpression.

Decreased neutrophil function in newly diagnosed multiple myeloma patients is restored with lenalidomide therapy

“…Not unexpectedly, BM phagocytes were most affected. These findings are in line with previously published data by Romano et al 22,23 The compromised neutrophil function in our assays could not be explained by lack of immunoglobulins (hypogammaglobulinemia), since opsonized E. coli, with immunoglobulin and complement from pooled sera, was used as stimuli.…”

“…The FcγRI/CD64 is, in contrast to CD16, upregulated in NDMM patients, suggesting that the neutrophils from these patients are chronically activated. 23 Lenalidomide treatment further increases both the CD64 expression, as well as the neutrophils ability to perform oxidative burst and phagocytose. In this material, the decreased phagocyte function at diagnosis could not be correlated to variation in P-Ca levels, inflammatory activity, or degree of BM plasma cell infiltration.…”

Neuron- and microglia-specific immunoexpression in steroid-independent male sexual behaviour in castrated B6D2F1 male mice

“…Another limitation was the normalization method we used. This normalization method has been used in multiple flow cytometry studies (Bhowmick et al ., 2020; Romano et al ., 2021; Soh et al ., 2021; Ditzig et al ., 2022), and follows a similar logic to the ddCt method used for qPCR (Pabinger et al ., 2014). In this way, each pair of the comparison group and the control group would combine into only one data point to reflect only their difference.…”

“…The MdFI of SI persistent maters were normalized with the pseudorandomized paired SI non-maters (Supplementary Table 1) by the resolution metric. The resolution metric is commonly adopted in flow cytometry experiments (Romano et al ., 2021; Soh et al ., 2021; Özgün & Garipcan, 2021; Ditzig et al ., 2022), because it is able to account for various sources of noise in flow cytometry data (Bhowmick et al ., 2020). In our experiment, the resolution metric is defined as (MdFI SI persistent maters – MdFI SI non-maters )/(rSD SI persistent maters + □rSD SI non-maters ).…”

Neutrophils, Fast and Strong

“…The functional activity of neutrophils is very strongly impaired in hematological malignancies, predisposing to tumor growth and resistance to chemotherapy. It has been established that the immunomodulatory drugs lenalidomide and pomalidomide improve the functional activity of neutrophils [ 8 ].…”