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B Cells and T Cells

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Plasma B Cells

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Summary

Plasma B cells are a subset of activated B-lymphocytes. They produce soluble antibodies against specific antigens. On microscopy, plasma B-cells are distinguished by their clock-faced chromatin distribution and eccentric nuclei. Plasma cells are typically found in the bone marrow.

Key Points

  • Plasma B Cells
    • Effector B-cell produced after B-cell Activation
    • Provide humoral immunity by producing antibodies against an antigen
    • “Clock face” nuclear chromatin and eccentric (off-center) nucleus
      • Eccentric nucleus due to large RER/Golgi secondary to robust antibody production
    • Found in bone marrow
      • Activated B-lymphocytes migrate from lymphoid tissue back to marrow
      • Normally do not circulate in peripheral blood