Hello Muhammad Rashid Khan,

Yes, bone marrow cells must be free of RBCs before being cultured in media. This is because RBCs can interfere with the growth and differentiation of bone marrow cells, particularly hematopoietic stem cells (HSCs) and mesenchymal stem cells (MSCs). So, you make use of RBC lysis buffer to selectively remove RBCs. The lysis buffer is designed to selectively disrupt the membranes of red blood cells, releasing their contents while leaving nucleated cells, largely intact.

Culture the bone marrow cells in DMEM supplemented with 20% FBS. A concentration of 20% FBS is frequently used in bone marrow cell cultures to provide adequate support for cell growth and expansion. While 20% is common, other FBS concentrations, like 10% or even lower, may be used depending on the cell type and experimental goals. 

The drug's effect is dependent on the complex biological environment of the living mouse, including its circulatory system, immune response, and other cells interacting with the bone marrow. When bone marrow cells are cultured, they are isolated from these interactions. Moreover, the mouse's body would have metabolized and cleared the drug over time. Even if the drug had a long half-life, the concentration in the cultured cells would be significantly lower than in the living animal. There are some drugs that have long-lasting effects, but this is less likely to be the case when cells are cultured outside the body. 

So, even if the drug may have caused changes in the bone marrow cells while in mouse, culturing those cells in vitro is likely to dilute or eliminate the drug's effect.

Best,

Malcolm Nobre Bundle of Thanks. I understood very well. I appreciate your answer.