Presence and distribution of biogenic amines (histamine, serotonin and epinephrine) in immunophenotyped human immune cells

Abstract.

Objective:

In animal experiments many hormones were demonstrated in immune cells. However, very few data are at our disposal in the case of human immune cells. In an earlier experiment, ACTH, endorphin and T₃ were studied and found in different subsets of human immune cells. Here, three biogenic amines (histamine, serotonin and epinephrine) were studied.

Methods:

Biogenic amine content of immunophenotyped human lymphocytes from 15 blood donors were investigated by multicolor flow cytometry using anti-biogenic amine antibodies. Monocytes and granulocytes separated by size and granularity were also studied.

Results:

Each biogenic amine could be detected in each subset of leukocytes, except epinephrine and serotonin in granulocytes. Activated T cells contained a higher amount of the amines, and CD19+B cells a higher amount of histamine, related to the whole lymphocyte population and to other subsets. Monocytes contained more histamine and epinephrine than lymphocytes and granulocytes contained twice as much histamine as monocytes and three times as much as lymphocytes.

Conclusion:

Human lymphocytes contain the three biogenic amine, similar to rat. However, while each amine was present in monocytes, in granulocytes serotonin and epinephrine were not demonstrated. The results call attention to the possible extrapolation of animal data to human lymphocytes and monocytes, but in the case of granulocytes, caution is needed. Taking into consideration earlier results, activated T cells appear to have an important role in the loss or production of hormones inside the immune system.