The Mixed Lymphocyte Reaction (MLR) is a classic **in vitro** assay used historically to assess the degree of **histocompatibility** between a potential donor and recipient, primarily for **hematopoietic stem cell transplantation (HSCT)**. In a one-way MLR, lymphocytes from the potential donor are irradiated or treated to prevent their proliferation (serving as 'stimulator' cells). These are mixed with lymphocytes from the recipient ('responder' cells). If the recipient's T-cells recognize foreign HLA antigens on the donor cells, they will proliferate. The amount of proliferation, measured by radioactive thymidine incorporation or other methods, indicates the strength of the **alloreactive T-cell response**. A strong MLR indicates significant HLA disparity and predicts a higher risk of **graft rejection** and **graft-versus-host disease (GVHD)**. While modern HSCT relies heavily on high-resolution DNA-based HLA typing, the MLR was an important functional test of cellular compatibility. For solid organ transplants, crossmatching (detecting pre-formed antibodies) is more critical than MLR.

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Zambia

• Naomi Miselo – 31 pts

• Visual Pathway Lesions
• Positive and Negative Symptoms
• Hallucinations and Delusions
• Antipsychotic Medications
• Emergency: Environmental Emergencies