Natural killer augmentation in systemic lupus erythematosus via a soluble mediator derived from human lymphocytes

Induction of T-cell proliferation and enhancement of NK activity by supernatants from Con A-stimulated human peripheral blood mononuclear cells: a new lymphokine

Supernatants from human peripheral blood mononuclear cells activated by Con A contain a factor(s) that stimulates blastogenic activity of normal human peripheral blood mononuclear cells. This Con A supernatant (CAS) contains stimulatory activity for E-rosette positive lymphocytes (T cells) and requires adherent cells for stimulation of T-cell proliferation. CAS does not contain detectable amounts of IL-2 as determined by its inability to support CTLL cell growth. Nor does it contain IL-1 or interferon. Examination of functional activity of lymphocytes stimulated for 3 days by CAS revealed that NK activity is augmented. This supernate does not appear to have any direct effect on B-cell function, although it induces suppression of polyclonal PWM stimulation of immunoglobulins. Thus, CAS appears to contain a new cytokine with immunomodulating potential.

Systemic lupus erythematosus and human development

The symptoms of systemic lupus erythematosus (SLE) suggest that the manifestations of the disorder are related to known or plausible control mechanisms in embryogenesis. It is suggested that homo sapiens has, in the course of evolution, developed novel processes controlling development.

Baseline and interferon-enhanced natural killer cell activity in rheumatoid arthritis

Natural killer (NK) cell activity against the leukemia cell line K-562 was tested in 45 patients with rheumatoid arthritis (RA) who either had not received any remission-inducing drugs for more than 6 months or had received penicillamine for at least 6 months. Baseline NK cell activity and interferon (IF)-enhanced NK cell activity did not differ from that observed in 45 controls matched for age and sex, and neither NSAID (non steroidal anti-inflammatory drugs) nor penicillamine influenced NK cell activity. There was no correlation between NK cell activity and acute-phase reactants.

Methylprednisolone pulse therapy induced fall in natural killer cell activity in rheumatoid arthritis

Natural killer (NK) cell activity was studied in 8 patients with classic or definite rheumatoid arthritis (RA) by investigating the killing of K 562 cells by peripheral blood lymphocytes before, during, and after intravenous methylprednisolone pulse therapy (MPPT). MPPT produced a considerable fall in NK activity and after 3 months NK activity was less than half that before MPPT.

Anaplastic myeloma in systemic lupus erythematosus

We describe a patient with systemic lupus erythematosus who developed an unusual form of anaplastic myeloma. Possible relationships between the two disease, and the role played by immunosuppressive therapy, are discussed.

Impaired natural killer cell function in systemic lupus erythematosus. Relationship to interleukin-2 production

Immune regulation requires clonal expansion of regulatory T cells which is dependent on the presence of interleukin-2 (IL-2). Previously, both natural killer (NK) cell function and IL-2 production were found to be depressed in systemic lupus erythematosus (SLE). This study was designed to determine the relationship between IL-2 production and NK cell activity in SLE. NK activity as determined by a standard 4-hour 51Cr-release assay was impaired in SLE (11.0 +/- 5.1 lytic units/10(7) cells) compared with controls (25.1 +/- 7.1 lytic units/10(7) cells) (P less than 0.05). IL-2 production was induced with concanavalin A and phorbol ester and quantitated using the IL-2 dependent cell line HT-2. IL-2 production was impaired in only 1 SLE patient, despite concomitant abnormalities in NK function in the SLE group as a whole. Moreover, in patients with impaired NK activity, incubation of lymphocytes with exogenous IL-2 did not restore NK activity to normal levels. These findings demonstrate that impaired NK activity in SLE is independent of IL-2 production and that defects in IL-2 production in SLE may not be as common as previously reported.

Natural killer cells in systemic lupus erythematosus. Abnormal numbers and functional immaturity of HNK-1+ cells

A monoclonal antibody, HNK-1, that detects a differentiation antigen on human granular lymphocytes with natural killer (NK) activity was used to enumerate this subpopulation in the peripheral blood of 14 patients with systemic lupus erythematosus (SLE). Nine patients had severely decreased numbers of HNK-1+ cells, 3 patients had elevated levels of HNK-1+ cells, and 2 patients had appropriate numbers of HNK-1+ cells compared with the levels in 112 normal controls. All SLE patients exhibited low NK killing ability against K562 target cells compared with controls. An increased proportion of the HNK-1+ cells was categorized as immature granular lymphocytes in over 50% of the SLE patients because their HNK-1+ cells coexpressed the OKT3 antigen and contained a paucity of cytoplasmic granules. The numbers of HNK-1+ cells or the HNK-1+ OKT3+ subgroup did not correlate with steroid therapy. This evidence suggests that levels of HNK-1+ lymphocytes are abnormal and functionally immature in most SLE patients. Longitudinal studies conducted over several months on a number of SLE patients demonstrated fluctuations in the ratio of mature and immature HNK-1+ cells and total HNK-1+ cells. Additional patients tested over longer periods of time will have to be studied to determine whether the proportion of mature NK cells (HNK-1+ OKT-) and immature NK cells (HNK-1+ OKT3+) will be useful in predicting the clinical course of disease.

Deficient natural killer cell (NK) activity and macrophage functioning in schizophrenic patients

The cytotoxic potential of mononuclear blood cells from 27 chronic schizophrenic patients was evaluated using quantitative measures of natural killer cell activity and macrophage inhibition of tumor cell growth. 44% of the patients had some evidence of deficient in vitro mononuclear cell function which was not correlated with a qualitative or quantitative alteration in the histologic appearance of these peripheral blood cells.