Human T lymphocytes in aging and malignancy: Abnormalities in PHA-induced Ia antigen expression and in functional activity in autologous and allogeneic MLR

Immune Reactivity in Aging – Autologous Mixed Lymphocyte Responses

“…Secondary auto crine stimulation also occurs in the cell mix tures, causing CD8 and B-cell stimulation as well. In a physiological sense, the AMLR reac tion has been considered as one that may, in an in vivo form, exert some element of im mune regulation and immune response am plification because of its action of generating increased amounts of helper, suppressor and lymphocytotoxic cell (NK) activity [32], The AMLR responses have been found to be reduced in a variety of different medical conditions, especially those that affect the im mune system through autoimmunity or lym phoma [9,12,17,25,29,33], In systemic lupus erythematosus patients showing re duced AMLR, there appears to be an impair 305 ment of the generation of suppressor cells in the reaction [ 12], a finding considered to be of some relevance to the course of lupus itself.…”

“…16-22]. The activation of autoreactive T cells with specificity for self-MHC may represent a means by which self-versus non-self-discrimination and autoimmunity are regulated [ 17], The AMLR has been studied in the normal aging population as well as in many disease states [23][24][25][26], While most studies indicate a reduced activity and generation of effector cells, there has not been complete agreement. Fournier and Charriere [24] noted an increase in AMLR responses in the female subjects of their aging population study.…”

Abnormalities of T cells isolated from mediastinal lymph nodes and peripheral blood of patients with lung carcinoma: deficit in PHA-induced expression of HLA class II antigens and in autologous mixed lymphocyte reactions

“…The rosette assay with 2-aminoethylisothiouronium bromide sheep red blood cells (AET-SRBCs), the indirect rosette microassay, activation with PHA and MLRs were performed as described elsewhere [4,6,15]. DNA synthesis was measured by pulsing triplicate cultures with 1 IxCi 3H-thymidine (sp.…”

“…Analysis of peripheral blood T (PB-T) cells from patients with solid tumors has identified a defect in the appearance of HLA Class II antigens following in vitro stimulation with phytohemagglutinin (PHA) and in their proliferative and stimulatory activity in autologous mixed lymphocyte reactions (MLR) [6]. Whether these abnormalities represent the cause or the consequence of the malignant disease is not known.…”

Impaired killer cell generation in the autologous mixed leukocyte reaction by rheumatoid arthritis lymphocytes

“…The suppressive effect of aging on the AMLR has also been reported (25)(26)(27). The situation in rheumatoid arthritis (RA) is less clear, with some investigators reporting near normal (28) and others reporting depressed AMLR (29)(30)(31)(32).…”