Phytohemagglutinin Transformation and Circulating Lymphocyte Subpopulations in Insulin-dependent Diabetic Patients

Abstract

The lymphocyte transformation response to the mitogen phytohemagglutinin (PHA) was determined in forty well controlled insulin-dependent diabetics, forty matched normal subjects and fourteen poorly controlled insulin-dependent diabetics. There was no significant difference in the PHA responses of normal subjects and well controlled diabetics, but poorly controlled diabetics showed a marked depression of lymphocyte transformation.Peripheral blood T and B lymphocyte subpopulations were also measured in fifteen normal subjects, fifteen well controlled diabetics and ten poorly controlled diabetics. The results showed no significant difference between normal and diabetic subjects, whether well or poorly controlled.The depressed PHA response in poorly controlled diabetics would seem to reflect inadequately corrected metabolic disturbance rather than an inherent, genetically determined immunologic abnormality. DIABETES 23:708-12, August, 1974.Recent studies have examined the role of cellmediated immune mechanisms in diabetes mellitus. For example, the leucocyte migration test (LMT) 1 has reportedly shown cellular hypersensitivity in diabetics against both nonspecific antigens (human and rat liver mitochondria 2 ) and an antigen derived from the microsomal fraction of the islets of Langerhans (porcine pancreatic antigen 3 ). In the latter study a positive correlation was found between the LMT response and delayed-type skin hypersensitivity to the antigen. 3Other investigators have used the lymphocyte transformation response to the mitogen phytohemagglutinin (PHA) 4 as an in vitro test of cell-mediated immune function: some record the PHA response to be impaired with diabetic lymphocytes, 5 suggesting immunologic abnormality, while others report it to be normal. 6 To re-examine these results we have measured the lymphocyte transformation response to PHA in well controlled and poorly controlled insulindependent diabetics and in normal subjects; in addition erythrocyte rosette 7 " 9 and in indirect immunofluorescence 7>9 technics have been used to compare the numbers of circulating T and B lymphocytes in peripheral blood from these three groups. PATIENTS AND METHODS PatientsPHA responses were studied in forty well controlled diabetic and forty normal subjects who were carefully matched for age and sex. The diabetic subjects (twenty-two women, eighteen men; mean age 42.4 years) were insulin-dependent, attended an outpatient clinic, and were free from infection on the day of study. The control subjects were healthy volunteers, mainly laboratory personnel or hospital outpatients not known to have endocrine disease or immunologic abnormality.PHA responses were also studied in a group of fourteen poorly controlled insulin-dependent diabetics. These patients had been brought to an outpatient clinic for routine or emergency review and their disorder was judged to be poorly controlled by the following criteria: midmorning blood glucose exceeding 350 708 DIABETES, VOL. 2 3 , NO. 8

Common infections in diabetes: pathogenesis, management and relationship to glycaemic control

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Excess Risk of Dying From Infectious Causes in Those With Type 1 and Type 2 Diabetes

“…However, there are some data to suggest that it could, in part, relate to a compromised immune system. Short-and long-term hyperglycemia may disturb immune functions such as neutrophil bactericidal function (13), cellular immunity (14), and complement activation (15). These defects in the immune system, along with vascular insufficiency, render patients with diabetes at higher risk for a variety of severe or invasive infections compared with those without diabetes (16).…”

Reduced protection against hepatitis B virus following vaccination in patients with Type 1 (insulin-dependent) diabetes

“…The number of circulating helper (CD4) cells is reduced [2], the helper/suppressor (CD4/CD8) lymphocyte ratio is decreased [3,4], phagocytic activity is impaired [5] and lymphocyte blastogenesis is reduced [6]. These are amongst the most consistent alterations reported in vitro and may well account for the greater susceptibility to infection in patients with poor metabolic control [7].…”