Optimization of a monoclonal antibody “Pwlam” for use to diagnose AL Amyloidosis

Sammanfattning

Amyloidosis is a group of diseases that originate from misfolded proteins. These proteins form fibrils which is stored in the tissue and organs. Approximately three to twelve per million people are diagnosed with amyloid light chain immunoglobulin amyloidosis (AL) each year and the median age is 65. The prognosis for AL amyloidosis is poor with a median survival rate of six months to three years. The patients may survive an additional 15-20 years with treatment such as stem cell transplantation. The aim of this rapport was to optimize a monoclonal antibody named pwlam to diagnose AL λ amyloid with immunohistochemistry (IHC) when the amount of sample is small. In this rapport three different methods were used, pressure preparation, IHC and western blot. For both pressure preparation and IHC, colour development occurred in case of positive results. Western blot was used as a quality control for the tissue since they were all originally diagnosed using that method. A total of 26 samples were tested, 16 positive AL λ samples, five AL κ samples and five negative samples. Pwlam is developed against AL λ so the AL κ samples function as a quality control for the antibody since it doesn’t bind to the κ light chains. A total of seven AL λ samples had a good binding with pwlam. More research is needed before pwlam can be used in IHC on pressure preparations as a supplementary method to diagnose samples when the amount of AL λ amyloid is small.