Lactoferrin-induced up-regulation of zeta (zeta) chain expression in peripheral blood T lymphocytes from cervical cancer patients.

Alteration of T-cell-associated signal transduction molecules has recently been implicated in immune suppression in tumour-bearing hosts. Here we report the immunoregulatory effects of human lactoferrin (LF) on zeta-chain expression in peripheral blood T lymphocytes from cervical cancer patients and healthy donors. By quantitative flow cytometry analysis, we demonstrated that the mean zeta-chain expression was significantly higher in freshly-isolated T lymphocytes from healthy donors (69%), compared with the patients (38%). Following 3-day culture under standard conditions, zeta-chain expression in T lymphocytes from the patients increased significantly, whereas it dropped in the cells from healthy donors. Anti-CD3 MoAb as well as LF, significantly increased expression of zeta-chain in T cells both from patients and control subjects. The addition of LF to the anti-CD3 MoAb cell cultures resulted in an even higher stimulation of the zeta-chain expression. The results suggest that, in patients with cervical cancer, zeta-chain defects could be corrected by the therapeutic application of LF.

Cell cycle regulatory proteins and apoptosis in B-cell chronic lymphocytic leukemia.

BACKGROUND AND OBJECTIVES: The pathogeny of B-cell chronic lymphocytic leukemia (B-CLL) involves both deregulated proliferation and inhibition of cell death. A particular role in the regulation of these phenomena is played by proteins involved in early G1 phase regulation: pRb kinases: cyclin-dependent kinases (cdk): cdk4 and cdk6 activated by cyclins D, and universal cdk inhibitor p27(Kip1). DESIGN AND METHODS: We determined by flow cytometry the expression of p27(Kip1) and cyclins D (D2 and D3) in populations of peripheral blood lymphocytes obtained from 59 (for p27(Kip1)) and 31 (for cyclins D) previously untreated patients with B-CLL, and compared them with cell cycle parameters, cell viability and apoptosis in 72-hour cultures in medium only. As a control we determined the expression of p27(Kip1), cyclin D2 and D3 in peripheral blood CD5+/CD19+ lymphocytes from 15 healthy donors. RESULTS: p27(Kip1) was present in nearly 100% of lymphocytes in all B-CLL populations tested. Its cellular content estimated semiquantitatively by specific mean fluorescence intensity was higher than in normal CD5+/CD19+ lymphocytes, p27(Kip1) was inversely correlated with patients' age and not correlated with other clinical variables, cell cycle or apoptosis rate. Cyclin D2 was detectable in 25 out of 31, and cyclin D3 in all B-CLL lymphocytes populations studied. In contrast to p27Kip1 present in all CD5+/CD19+ lymphocytes, both cyclins were detected only in a subset of neoplastic cells: 27.5 to 87% (mean 51.2) for cyclin D2 and 20.3 to 98% (mean 76.5) for cyclin D3. In cyclin D2- and D3-positive normal CD5+/CD19+ lymphocytes and B-CLL cell populations, cyclin D3 was expressed in a higher percentage of cells than cyclin D2. Both cyclin D2-and cyclin D3-positive fractions of B-CLL cells were, on average, larger than corresponding fractions of normal CD5+/CD19+ peripheral blood lymphocytes. INTERPRETATION AND CONCLUSIONS: Our results indicate that cyclin D3 plays an important role in the regulation of normal and neoplastic CD5+/CD19+ cells, and point to the possibility of the exit of a number of CLL lymphocytes from quiescence.

Expression of Fas antigen on T cell subpopulations in peripheral blood of patients with relapsing-remitting multiple sclerosis.

BACKGROUND: During the relapse of multiple sclerosis, the activation of T cells, autoreactive to myelin antigens in blood, enhanced and maintained as a result of anomalous mechanisms of their earlier elimination, leads on para- and autocrine basis to the activation of antigen- non-specific cells of immune system. In consequence, activated cells secrete a range of proinflammatory cytokines and display activation antigen expression on their surface, which results in blood-brain barrier damage. The differentiation of lymphocytes into effector cells in blood during MS relapse is to increase the number of cells supporting inflammatory reactions and simultaneously to reduce the number of cells which play a role of suppressors. Fas antigen is present among activation antigens found on T cells. Once this antigen has been combined with the ligand, it transmits apoptic signal to the cell. The presence of Fas antigen on activated peripheral blood T cells may enable us to estimate their activation and it may also indicate a potential to eliminate those cells from blood. The aim of the study was to provide a quantitative assessment of the subpopulations of CD3, CD4 and CD8 lymphocytes in peripheral blood and to investigate Fas antigen expression on these subsets in patients with relapsing-remitting multiple sclerosis, in relation to clinical activation of the disease. MATERIAL AND METHODS: Thirty-five patients participated in the study, including 14 patients finding themselves in clinical relapse of the disease and 21 patients in the state of remission. Additionally, 21 healthy subjects were included. Quantitative assessment of individual subpopulations and Fas co-expression was carried out with the use of monoclonal antibodies anti CD3, CD4 and CD8 as well as anti CD95 antibodies, and flow cytometer Pas/Dako Galaxy. RESULTS: The differences in the percentage of particular lymphocytes between 3 groups proved insignificant. Patients in the relapse of the disease showed significantly greater Fas expression on subpopulations CD3 and CD4 when compared to the results obtained from remission patients and control subjects. This difference was not observed for Fas expression on subset CD8. CONCLUSIONS: The investigation of Fas receptor expression may be useful in order to monitor clinical course of the disease, which is characterised by the periods of exacerbation and remission.