Modulation of mTOR Effector Phosphoproteins in Blood Basophils from Allergic Patients

Abstract

The mammalian target of rapamycin (mTOR) pathway contributes to various immunoinflammatory processes. Yet, its potential involvement in basophil responses in allergy remains unclear. In this pilot study, we quantified two key mTOR effector phosphoproteins, the eukaryotic initiation factor 4E (peIF4E) and S6 ribosomal protein (pS6rp), in blood basophils from nut allergy patients (NA, N= 16) and healthy controls (HC, N= 13).Without stimulation in vitro, basophil peIF4E levels were higher in NA than HC subjects (P=0.014). Stimulation with nut (offending) but not chicken / rice (non-offending) extract increased basophil peIF4E and pS6rp levels (+32%, P=0.018, and +98%, P=0.0026, respectively) in NA but not HC subjects, concomitant with increased surface levels of CD203c and CD63, both known to reflect basophil activation. Pre-treatment with the mTOR inhibitor rapamycin decreased pS6rp and CD203c responses in nut extract-stimulated basophils in NA subjects. Thus, basophil responses to offending allergens are associated with modulation of mTOR effector phosphoproteins.

Food allergy: A practice parameter update—2014

“…Basophil and eosinophilic reactivity tests have been shown to be associated with food-induced allergic responses and have been shown in current research to be modified over time during immunotherapy. [94][95][96][97][98]103,104 Indexes of cell-mediated immunity, such as lymphocyte proliferation, have been implicated as possible correlates of food hypersensitivity, with relatively greater proliferation seen in patients with food allergy, but these assays are not specific. 94,98,105 The role of specific cytokine profiles in serum or peripheral mononuclear cells of patients with food allergy remains under study and has not been well established to date.…”

The basophil surface marker CD203c identifies Aspergillus species sensitization in patients with cystic fibrosis

“…18,25,26 Briefly, venous blood was collected in S-Monovette ® ethylenediaminetetraacetic acid (EDTA) blood tubes (Sarstedt, Germany) and centrifuged at 400g for 10 min at 4 °C. The supernatant was further centrifuged at 3000g for 10 min at 4 °C and 97 µl of platelet-free plasma was added to 100 µl of erythrocyte/leukocyte pellet and incubated for 30 s at 37 °C.…”

Blood basophils from cystic fibrosis patients with allergic bronchopulmonary aspergillosis are primed and hyper-responsive to stimulation by aspergillus allergens

“…rAsp f1 was obtained from Indoor Biotechnologies Inc. (Charlottesville, VA, USA). For each of the three types of incubation [conditions (ii), (iii-iv) and (v) listed above], 100 μl of platelet-free, reconstituted blood, was mixed with either 3 μl of PBS or relevant extracts for 10 and 30 minutes at 37°C [28]. Incubations were stopped by adding ice-cold PBS with EDTA (2.5 mM final) and cells were pelleted by centrifugation (490 G, 5 minutes, 4°C) for surface staining.…”

“…Surface staining for CD203c, CD63 and CD123 was performed prior to fixation as described elsewhere (see [28]). Data was acquired …”