Annexin A1 Test

Annexin A1 aka Lipocortin is a protein and an antibody to the ANXA1 gene family. It is normally expressed clinically in stem cells and cancer stem cells. Research studies on genetics have established that anyone who tests positive for Annexin A1 antibody must be diagnosed and treated for Hairy Cell Leukemia. This type of blood cancer is slow growing and results in excessive lymphocytes in the bone marrow. That’s why people with hairy cell leukemia have low levels of red blood cells, white blood cells and platelets. Annexin A1 test is performed during and after the treatment of Hairy Cell Leukemia.

Samples for testing Annexin A1 are collected from a person’s serum, plasma, tissue homogenates and other biological fluids. If Annexin A1 test is performed on a blood sample to measure the level of Annexin A1 in the blood, then no special preparation is required. If Annexin A1 test is performed on a sample of bone marrow tissue to measure the level of Annexin A1 in the tissue, then preparation for biopsy is required. For both the cases, you need to inform your doctor about the impending test. Also, mention if you are on any medications. In case you have any medical conditions or allergies, it’s advisable to discuss them with your doctor. Specific instructions by the doctor must be adhered to.

In case of positive result, Hairy Cell Leukemia is detected for both sexes and across all age groups. In case of negative result, although Annexin A1 is negative in normal B-cells or B-cell tumours, it stains myeloid cells, macrophages, and subsets of benign T-cells (cancer stem cells).

As samples for testing Annexin A1 may vary from case to case, special arrangements need to be made in order to keep the sample intact and test worthy. Usually, the sample is stored and preserved in the following ways: In a formalin-fixed, paraffin-embedded block the tissue is stored. In unbaked and unstained slides that are specially cut to suit the purpose of testing Annexin A1.

Block and slide identifiers are labeled and matched with the specimen ID. This is of paramount importance to avoid errors of any sort. Cold packs are used for transportation and it’s made sure that the cold pack is not in direct contact with sample collected. The test kit is targeted for in vitro quantitative measurement of Annexin A1. Testing is done based on Immunohistochemistry method on the sample, commonly known as histopathy.