Separation of normal mature bone marrow plasma cells

Area of Science:

• Immunology
• Hematology
• Cell Biology

Background:

• Normal plasma cells are crucial for adaptive immunity but challenging to isolate for in vitro study.
• Existing methods for plasma cell separation are often inefficient or yield impure cell populations.

Purpose of the Study:

• To develop and validate a robust, multi-step purification process for isolating normal bone marrow plasma cells.
• To achieve a high-purity plasma cell fraction suitable for physiological investigations.

Main Methods:

• A three-phase purification strategy involving buoyant density separation, selective cell culture, and enzymatic disaggregation with adherence-based stromal cell removal.
• Utilized bone marrow from normal humans and baboons, avoiding known B cell activators.

Main Results:

• Bone marrow fragments, separated in Phase I, showed higher plasma cell enrichment compared to cell suspensions.
• Phase II culture concentrated plasma cells by exploiting differential affinities with stromal cells, achieving maximum enrichment within 7 days.
• Phase III disaggregation and stromal cell removal yielded a non-adherent fraction comprising approximately 85% plasma cells.

Conclusions:

• The described three-phase purification process effectively isolates normal bone marrow plasma cells with high purity.
• This method facilitates direct quantitative evaluation of normal plasma cell physiology in vitro, advancing immunological research.