PERIPHERAL-BLOOD LYMPHOCYTES OF BIPOLAR AFFECTIVE PATIENTS HAVE A HISTONE SYNTHETIC PROFILE INDICATIVE OF AN ACTIVE CELL STATE

1. Although abnormaltiies of the immune system have been described in depression, no information exists regarding the biochemical parameters which could characterize the physiological state of lymphocytes from patients with bipolar affective disorder. 2. Lymphocytes of normal con trol subjects are known to be in the Go resting phase of the cell cycl e. Histone synthesis is characteristically different during the Go, G1 /G2 and the S phases of the cell cycle. As such, it can be used as a b iochemical marker with which to distinguish between cycling and noncyc ling cells. 3. In order to investigate the possibility of whether or n ot the lymphocytes of patients with bipolar affective disorder are in an activated state, typical of cycling cells, total histone and histon e variant synthesis were analysed in peripheral blood lymphocytes of a group of 12 patients with bipolar affective disorder and 7 normal con trols. 4. According to the histone variant synthesis pattern, lymphocy tes of patients in normothymia have values similar to those of control s, i.e., of noncycling cells, while patients in either the depressed o r the manic phase have values intermediate to those of resting and cyc ling cells 5. This study shows that histone synthesis can perhaps be u sed as a biochemical parameter of possible significance in differentia ting amongst the three phases of the illness.