Final answer:
Ig loci rearrangement by RAG-1/2 occurs in developing B cells, which are part of the adaptive immune system and mature in the red bone marrow. This process is crucial for creating diverse antibodies to respond to various antigens.
Step-by-step explanation:
Cells with Rearranged Ig Loci by RAG-1/2
The Ig loci are rearranged by RAG-1/2 in developing B cells. These cells, part of the adaptive immune system, are born in the red bone marrow and mature there as well. The process of Ig loci rearrangement is essential for creating a diverse range of immunoglobulins capable of binding specifically to a plethora of antigens. This mechanism plays a pivotal role in the adaptive immune response, facilitating the differentiation of B cells into mature antibody-secreting plasma cells. T cells also undergo a similar process of gene rearrangement for their T-cell receptors; however, this takes place in the thymus rather than the bone marrow. Both B and T cells are derived from stem cells in the bone marrow but have distinct maturation sites and functions within the immune system.