Differences in Regulatory Mechanisms Induced by β-Lactoglobulin and κ-Casein in Cow’s Milk Allergy Mouse Model–In Vivo and Ex Vivo Studies

Abstract

The presence of various proteins, including modified ones, in food which exhibit diverse immunogenic and sensitizing properties increases the difficulty of predicting host immune responses. Still, there is a lack of sufficiently reliable and comparable data and research models describing allergens in dietary matrices. The aim of the study was to estimate the immunomodulatory effects of β-lactoglobulin (β-lg) in comparison to those elicited by κ-casein (κ-CN), in vivo and ex vivo, using naïve splenocytes and a mouse sensitization model. Our results revealed that the humoral and cellular responses triggered by β-lg and κ-CN were of diverse magnitudes and showed different dynamics in the induction of control mechanisms. β-Lg turned out to be more immunogenic and induced a more dominant Th1 response than κ-CN, which triggered a significantly higher IgE response. For both proteins, CD4+ lymphocyte profiles correlated with CD4+CD25+ and CD4+CD25+Foxp3+ T cells induction and interleukin 10 secretion, but β-lg induced more CD4+CD25+Foxp3- Tregs. Moreover, ex vivo studies showed the risk of interaction of immune responses to different milk proteins, which may exacerbate allergy, especially the one caused by β-lg. In conclusion, the applied model of in vivo and ex vivo exposure to β-lg and κ-CN showed significant differences in immunoreactivity of the tested proteins (κ-CN demonstrated stronger allergenic potential than β-lg), and may be useful for the estimation of allergenic potential of various food proteins, including those modified in technological processes.

The Immune System Response to 15-kDa Barley Protein: A Mouse Model Study

“…After homogenization using Fugamix (ELMI LTD, Riga, Latvia), samples were centrifuged on the Eppendorf 5418R centrifuge at 12,000× g for 10 min. Supernatants were collected and stored at −20 °C for further analysis [ 20 ].…”

“…The optical density (OD) was measured at 405 nm on the Jupiter UVM-340 spectrophotometer (ASYS Hitech GmbH, Eugendorf, Austria). The endpoint titers (EPT) were expressed as the reciprocal dilution of the last sample dilution of 0.1 OD above the negative control [ 20 ].…”

“…After 4 h of incubation, the optical density was read for each well at λ = 450 nm using the Jupiter UVM-340 spectrophotometer (ASYS Hitech GmbH, Eugendorf, Austria). Results were presented as the mean ± SD from five replicates [ 20 ].…”

Advances in the Study of Probiotics for Immunomodulation and Intervention in Food Allergy

“…This is because casein allergic reactions may trigger a Th2 response, disrupting the Th1/Th2 immune balance and predisposing the infant to sensitization by other milk proteins such as β-lactoglobulin and α-lactoglobulin [ 22 ]. These proteins have a complex tertiary structure and similarities in peptide chain conformation, recognizing similar T and B cell epitopes [ 23 ]. Dairy products are closely associated with food allergy and dysregulation of the body’s immune response, including IgE-mediated activation of mast cells and eosinophils, abnormal differentiation of CD4 lymphocyte subsets, and excessive production of pro-inflammatory cytokines [ 24 ].…”

Animal Models for the Study of Food Allergies

“…and on days 52, 59, and 66 with protein and CT i.g. (Zlotkowska et al., 2021). ( Q ) Protein and alum on days 0 and 14 i.p.…”