Search PubMed⌕ Search

Biomedical subjects

A Barabino

Publications and source records attributed to A Barabino.

At least 55 records · Page 3Linked to original sources
PubMed1985

Circadian variations of autologous mixed lymphocyte reactions and endogenous cortisol.

The degree of proliferation of human T cells stimulated with autologous PHA-T cells and with autologous non-T cells displays circadian variations. The highest proliferation occurs with cells isolated from blood drawn at 8 a.m. in mixed lymphocyte reactions (MLR) with autologous PHA-T cells and from blood drawn at 8 p.m. in MLR with autologous non-T cells. The circadian variations of autologous MLRs appear to reflect changes in the proliferative response of T cells. In autologous MLRs with non-T cells as stimulators the extent of proliferation was inversely correlated with the level of endogenous cortisol. The circadian variations of autologous MLRs do not reflect non-specific changes in the proliferative and stimulatory properties of T and non-T cells, since circadian variations were not observed in the proliferative response of T cells to mitogens and in allogeneic MLRs. Circadian variations of autologous MLRs must be taken into account when analyzing abnormalities of these reactions in pathological conditions.

Circadian Rhythm↗
PubMed1985

T-lymphocytes phenotype and functions in patients with head and neck cancer.

We studied the phenotype of T-lymphocytes isolated from 18 patients with head and neck cancer, their capacity to express Ia antigens upon activation by lectins in vitro, their capacity to function either as responder or stimulator cells in autologous mixed lymphocyte reaction, and their capacity to cooperate with the normal adherent suppressor cells (NASC). The T-lymphocytes isolated from these patients have several functional defects including an impaired capacity to activate allogeneic lymphocytes in mixed lymphocyte reactions (MLRs), a lack of a proliferative capacity in autologous MLRs, an impaired sensitivity to inhibition by NASC, and an impaired capacity to express Ia antigens upon activation by mitogens in vitro. These data indicate that, in patients with head and neck cancer, immune function is characterized by a defect in T-lymphocytes functions which concerns the process of cell to cell cooperation.

Aged↗
PubMed1984

Role of normal adherent cells in the regulation of the autologous mixed lymphocyte reactions in humans.

The effect of normal adherent suppressor cells on the blastogenesis of human T lymphocytes in the mixed lymphocyte reaction (MLR) was studied in both allogeneic and autologous combinations. Non-T cells and Ia+ T lymphocytes were used as stimulator cells in both allogeneic and autologous MLR. The addition of adherent cells to the stimulators inhibited blastogenesis of T lymphocytes in both types of MLR when the stimulator population was made up of non-T lymphocytes but did not interfere with blastogenesis when Ia+ T lymphocytes were used as stimulator cells. The present data indicate that the T lymphocytes able to respond to Ia+ T cells (in the MLR, autologous or allogeneic) may be different from those which respond to non-T lymphocytes or may be less sensitive to the regulatory function of normal adherent cells.

Cell Adhesion↗
PubMed1984

Decreased sensitivity of T lymphocytes to normal adherent suppressor cells in patients with head and neck cancer.

The sensitivity of T Lymphocytes to the inhibitory action of normal adherent cells in the mixed lymphocyte reaction (MLR) was studied in 20 subjects with head and neck cancer. T lymphocytes from cancer patients proliferated in the MLR both in the absence and in the presence of increasing numbers of autologous as well as allogeneic adherent cells, while the blastogenesis of T lymphocytes from controls was inhibited up to 70% by the addition of adherent cells to the culture. Such a lack of sensitivity to adherent cells in cancer patients occurred both in allogeneic and in autologous MLR. These observations indicate that the immunocompetence of patients with head and neck cancer may be related to a defect of macrophage-T lymphocyte interaction similar to the one described in patients with common varied immunodeficiency.

Adult↗
PubMed1984

Effect of single oral doses of prednisone and deflazacort on human lymphocyte distribution and functions. Analysis with monoclonal antibodies.

Two corticosteroids, prednisone and deflazacort, have been compared with respect to their capacity of inducing redistribution of T lymphocyte subsets, modification of expression of Ia antigens by PHA primed T cells, and inhibition of blastogenesis of T cells in autologous mixed lymphocyte reactions. Both corticosteroids were able to induce T lymphocytes depletion, increase of suppressor T cells, inhibit Ia expression upon mitogenic activation of T lymphocytes, and inhibit autologous MLRs either when non T cells or when PHA T lymphocytes were used as stimulators. We conclude that deflazacort may constitute a better glucocorticoid than prednisone for correcting the imbalance among T cells subsets, the helper T cells activity and the processes of cell-to-cell cooperation in immune diseases.

Adult↗
PubMed1983

Inhibitory effect of a low dose of prednisone on PHA-induced Ia antigen expression by human T cells and on proliferation of T cells stimulated with autologous PHA-T cells.

Administration of a small dose of prednisone markedly reduced (1) the PHA-induced expression of Ia antigens by T cells, (2) the stimulatory activity of Ia antigen-bearing T cells in autologous and allogeneic mixed lymphocyte reactions (MLRs), and (3) the proliferative response of T cells stimulated with autologous PHA-activated T cells or autologous or allogeneic non-T cells. The inhibitory effects of prednisone are reversible and are not detectable on T cells isolated from blood drawn 24 hr following prednisone administration. The kinetics of the prednisone-mediated inhibition of MLRs with autologous PHA-T cells is different from that of MLRs with autologous non-T cells. These data in conjunction with the information available in the literature suggest that the mechanisms underlying these two types of autologous MLRs are different.

Adult↗
PubMed1983

Multiple endocrine neoplasia type 2b (MEN 2b). Report of 2 pediatric cases.

Two new sporadic cases of multiple endocrine neoplasia type 2b (MEN 2b) are described. Both patients were diagnosed in pediatric age and presented the characteristic features of the syndrome (facies "sui generis", Marfanoid habitus, mucosal neuromas, history of chronic gastrointestinal disturbances) and developed medullary thyroid carcinoma (MTC). In the former case, metastatic neck adenopathies were the first sign by which the disease was recognized. Antitumor treatment consisted of total thyroidectomy, cervical node dissection, administration of I131 and neck irradiation. This patient is alive and well 20 months from diagnosis, still having high serum levels of thyrocalcitonin (TC). In the latter case, the syndrome was diagnosed on clinical grounds before the development of a MTC. The patient was then strictly followed-up and thyroidectomy performed only when serum TC levels rose to abnormally high values: no tumor spread was documented at that time. She is alive and well 4 years from diagnosis.--Early recognition of MEN 2b syndrome is necessary in order to detect and properly treat MTC.

Adolescent↗
PubMed1983

Role of distinct domains of Ia antigens in autologous and allogeneic mixed lymphocyte reactions.

Murine monoclonal antibodies (MoAb) to distinct determinants of human Ia antigens and low doses of prednisone induce different effects on the autologous mixed lymphocyte reaction (MLR), stimulated by PHA-T cells or by non-T cells, and on allogeneic MLRs. These results suggest that distinct domains of Ia antigens and/or mechanisms are involved in these types of MLRs.

Antibodies, Monoclonal↗
PubMed1981

[Diminished in vitro colony forming capacity of bone marrow cells in a case of chromosome 8 trisomy (mosaicism): criteria for "high risk" pre-leukemia syndrome].

A case has been described of Trisomy 8 mosaicism Syndrome. At onset the child presented with hyporegenerative anemia; the study of colony forming capacity in vitro (CFU) by Bone Marrow (B) and Peripheral Blood (PB) showed an abnormal colony formation by myeloid and erythroid progenitor cells. No immunological defects were discovered. The in vitro colony formation appears to have a definite role in the identification of patients who may be at higher risk of developing leukemia. The importance of 8 chromosome for hematopoiesis control is discussed.

Child, Preschool↗