Scientists in New York studying allergic disease have just published work citing the use of HemaCare-sourced bone marrow mononuclear cells for their research into the mechanisms of immunological memory.
The immune system is a wonderfully complex assembly of interacting cells and tissues that protect us from disease. To function properly, the cells within this system must detect and remember a wide variety of triggering agents.
When the immune system becomes overly sensitive to a specific trigger, the body can develop an allergic response to that trigger that in some cases is life-threatening. Understanding the mechanisms underlying allergic response development can help scientists develop treatments to prevent dangerous allergic reactions and improve the quality of life for many people.
The specific cell subsets supporting immunological memory are all derived from multipotent cells residing in the bone marrow. However, how the immune system “remembers” allergic triggers remains a mystery. The hypersensitive reaction of the immune system to an otherwise harmless substance is linked to Immunoglobulin E (IgE), an antibody that is produced by plasma cells, a type of white blood cell that originates in the bone marrow.
Based on earlier research, the authors hypothesized that the existence of a significant population of long-lived plasma cells expressing IgE (IgE+ plasma cells) might determine whether a progressively robust allergic response developed. To test their hypothesis, the group needed bone marrow mononuclear cells matching specific criteria. To meet their requirements, the authors obtained human cat-allergic and non-allergic donor bone marrow mononuclear cells and matching donor sera from HemaCare. HemaCare’s large donor database makes it possible to fulfill custom orders from pre-selected donors.
Using a mouse model, the researchers determined that short-term exposure (4 weeks) to an allergen resulted in the generation of IgE+ plasma cells residing mainly in the lymphoid organs. The cells do not produce allergen-specific IgE and are not capable of eliciting a severe allergic reaction. However, long-term exposure (15 weeks) to the same allergen led to the gradual accumulation of allergen-specific IgE+ plasma cells in the bone marrow. These cells were long-lived and capable of provoking a severe allergic reaction.
Building on these results, the authors examined human bone marrow mononuclear cells and sera from allergic and non-allergic donors. They were pleased to discover that their hypothesis was correct; a significant population of allergen-specific IgE+ plasma cells existed in the bone marrow of allergic donors, but not non-allergic donors. Furthermore, these cells were capable of eliciting a severe allergic reaction in humanized mice exposed to the allergen.
This research is a big step forward in the effort to devise better treatment strategies for those suffering from allergies. At HemaCare, we support research efforts to further characterize human bone marrow cell subpopulations in order to more effectively fight disease. For more information on HemaCare bone marrow products, please visit our website here. We also support the pre-clinical and clinical community with our recent launch of GMP-compliant bone marrow aspirate.
- Asrat S., et al. Chronic allergen exposure drives accumulation of long-lived IgE plasma cells in the bone marrow, giving rise to serological memory. Science Immunology. 5: 1-16. Jan 2020.