7/1/2023 0 Comments Cultural repertoire![]() ![]() The second tolerance checkpoint occurs during the transition from new emigrant (transitional 2 ) B cells to mature, naive B cells and acts to remove or inactivate self-reactive B cells that have escaped the first checkpoint ( 1– 4). Indeed, about 75% of early immature human B cells are self-reactive, as determined by the generation of recombinant Abs (rAbs) from single cells ( 1, 2).ĭuring the transition from surface Ig – early immature B cells to surface Ig + immature B cells in bone marrow, the first tolerance checkpoint removes the majority of polyreactive B cells and/or those reactive with nuclear antigens ( 1, 2). While this process enables the generation of humoral responses against a wide range of harmful microorganisms, it often generates autoreactive BCRs. The random recombination of V, D, and J Ig gene segments produces a highly diverse repertoire of B cell antigen receptors (BCRs). We propose that immune tolerance significantly reduces the scope of the BCR repertoire to microbial pathogens and that cross-reactivity between foreign and self epitopes may be more common than previously appreciated. Patterns of foreign+self-reactivity among mature B cells from healthy donors differ from those of SLE patients. In contrast, in SLE patients who are defective in the second tolerance checkpoint, frequencies of foreign+self-reactive B cells remain unchanged during maturation of transitional to mature B cells. In healthy donors, the majority (~70%) of transitional B cells that recognize foreign antigens also bind human self-antigens (foreign+self), and peripheral tolerance halves the frequency of foreign+self-reactive mature B cells. Here, we use single-cell cultures to determine the repertoires of human B cell antigen receptors (BCRs) before (transitional B cells) and after (mature B cells) the second B cell tolerance checkpoint in both healthy donors and in patients with systemic lupus erythematosus (SLE). Whereas a few microbial pathogens exploit these “holes” in the B cell repertoire by mimicking host antigens to evade immune surveillance, the extent to which tolerance reduces the B cell repertoire to foreign antigens is unknown. While low income and racialized communities draw less on dominant ethical eating repertoires, their eating practices are by no means amoral we document creative adaptations of dominant ethical eating repertoires to fit low income circumstances, as well as the use of different cultural frameworks to address moral issues around eating.Immunological tolerance removes or inactivates self-reactive B cells, including those that also recognize cross-reactive foreign antigens. We find that privilege does appear to facilitate access to dominant ethical eating repertoires, and that environmental considerations figure strongly in these repertoires. Drawing conceptually from cultural sociology, we explore how ethical eating constitutes a cultural repertoire shaped by factors such as class and ethno-cultural background, and how symbolic boundaries are drawn through eating practices. Our second goal is to investigate which participants have privileged access to ethical eating, and which participants appear relatively marginalized. ![]() We draw from 40 in-depth interviews with 20 families in two Toronto neighborhoods. To address these knowledge gaps, the first goal of this paper is to better understand how consumers from different class backgrounds understand ethical eating and work these ideas into everyday food practices. Scholars do not fully understand the extent to which privileged populations think about food ethics in everyday shopping, or how groups with limited resources conceptualize ethical consumption. While a hopeful trend, it raises the question of whether ethical consumption is primarily an elite social practice, especially since niche markets for ethical food products (for example, organics, fair trade) are thought to attract wealthy, educated consumers. ![]() Johnston, Josee Szabo, Michelle Rodney, AlexandraĮthical consumption is understood by scholars as a key way that individuals can address social and ecological problems. Good food, good people: Understanding the cultural repertoire of ethical eating Good food, good people: Understanding the cultural repertoire of ethical eating ![]()
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