Role of target and effector cell structures in natural killer-mediated cytotoxicity.

An analysis of target and effector cell structures involved in the in vitro natural killer (NK)-mediated cytotoxicity has been performed. The degree of surface expression of transferrin receptor (TR) was only in part correlated with that of cell lysis. Moreover, the lysis could not be blocked by treating target cells with two anti-TR monoclonal antibodies.

Phenotypic and functional characterization of the circulating NK compartment in hairy cell leukaemia.

A phenotypic and functional analysis of the circulating natural killer (NK) cell population was carried out in a series of patients with hairy cell leukaemia (HCL). The overall mean NK activity of both the mononuclear and T cell fractions was reduced compared to that of normal controls (466 lytic units (lu) v 573 lu and 226 lu v 381 lu, respectively), though this difference did not reach statistical significance (P less than 0.05).

Normal T-lymphocyte function in patients with Hodgkin's disease in long-lasting remission.

In 18 patients with Hodgkin's disease (HD) in long-lasting remission (more than 5 years), the distribution of circulating T-lymphocytes was analyzed using a series of monoclonal antibodies (OKT3, T4, T8, Leu-7, Leu-11 and T10) and correlated with cell function (helper capacity in a pokeweed mitogen system and natural killer (NK) activity). A reduced proportion of OKT4 (helper/inducer)-positive cells associated with a normal absolute number was consistently accompanied by a significant increase (p less than 0.005) in the proportion and absolute number of OKT8 (suppressor/cytotoxic)-positive cells.

Vimentin and keratin intermediate filaments expression by K562 leukemic cell line.

The expression of intermediate filaments (IMF) by K562 leukemic cell line has been studied by the use of polyclonal and monoclonal antibodies. These cells exhibited an extremely rich network of IMF reacting with both anti-vimentin and anti-keratin antibodies. Although these results need to be confirmed by different techniques, such as immunoblotting, they suggest the possibility that leukemic cell lines can express different types of IMF similarly to other cultured cells.

T-cell prolymphocytic leukaemia: a clinical and immunological study.

2 cases of T-cell prolymphocytic leukaemia (T-PLL) were investigated for their reactivity with a series of monoclonal antibodies (MoAbs) as well as for the cytochemical expression and functional activity of the pathological cells. Both patients showed morphological (large cells with abundant cytoplasm and eccentric and irregularly shaped nucleus with large and prominent nucleoli) and clinical (high leucocyte count and splenomegaly) features typical of T-PLL. The cells from 1 patient expressed a helper/inducer phenotype (T4+, T8-) and were reactive with the anti-Tac (interleukin-2 receptor) MoAb, while the other case co-expressed both the T4 and the T8 antigens.

Meningeal leukemia complicating prolymphocytoid transformation of B-chronic lymphocytic leukemia.

A patient who developed a meningeal leukemia during prolymphocytoid transformation of B-chronic lymphocytic leukemia is described. The central nervous system (CNS) complication occurred after 5 years of relatively benign course. Almost all CNS mononuclear cells showed the typical morphology and immunology of prolymphocytic leukemia cells, whereas a mixture of prolymphocytoid elements and small-sized lymphoid cells was observed in peripheral blood.

Deficiency of autologous mixed lymphocyte reaction in patients with idiopathic autoimmune hemolytic anemia.

Alterations in the autologous mixed lymphocyte reaction (autologous MLR) have been reported in many autoimmune diseases and in diseases with a derangement of T regulatory function. We have studied autologous MLR in 10 patients with idiopathic autoimmune hemolytic anemia (IAHA). All patients had decreased autologous MLR which averaged 4,106 +/- 1,332 cpm (SEM) compared to 12,153 +/- 4,166 cpm for simultaneously studied controls.

Functional behaviour and immunological phenotype of circulating B lymphocytes in multiple myeloma. Studies with pokeweed mitogen.

Peripheral blood B lymphocytes, depleted of adherent cells, from 10 patients with multiple myeloma were cultured in the presence of PWM with autologous or donor T lymphocytes. The results show that: (1) co-cultures with allogeneic T lymphocytes produced more plasma cells than those with autologous ones; (2) the kappa/lambda ratio overlapped the values obtained in normal controls, irrespective of the light chain produced by the neoplastic plasma cells and (3) the immunological phenotype of plasma cells obtained from PWM stimulated peripheral B cells (RFA2+, RFA3+, A10+) was clearly different from that one of myelomatous plasma cells (RFA2-, RFA3-, A10+). These data confirm the T cell imbalance already seen in myeloma patients; moreover they show that PWM responsive B cell are functionally normal and phenotypically different from bone marrow myeloma cells.

Membrane phenotype and functional behaviour of T lymphocytes in multiple myeloma: correlation with clinical stages of the disease.

The distribution of T lymphocyte subsets was assessed using monoclonal antibodies (MoAbs) in 44 untreated patients with multiple myeloma (MM) subdivided according to the clinical stage of the disease. A significant reduction (P less than 0.001) of T lymphocytes was observed only in stage II and III patients.