RESEARCH - Natural killer T cells in families of patients with SLE: possible role in IGG production

[Guest guest]

Arthritis Rheum. 2006 Dec 28;56(1):303-310 [Epub ahead of print]

Natural killer T cells in families of patients with systemic lupus

erythematosus: Their possible role in regulation of IGG production.

Green MR, Kennell AS, Larche MJ, Seifert MH, Isenberg DA, Salaman MR.

Imperial College School of Medicine, London, UK.

OBJECTIVE: To determine whether there is a link between the frequency of

natural killer T (NKT) cells and high levels of IgG in patients with

systemic lupus erythematosus (SLE) and their relatives. METHODS: Blood

samples were obtained from patients with SLE, their first-degree relatives,

patients with rheumatoid arthritis (RA), and healthy control subjects. The

frequency of NKT cells (defined as CD56+ T cells) was expressed as a

percentage of total blood lymphocytes. Plasma levels of total IgG and IgM,

and IgG antibodies to double-stranded DNA (dsDNA) were determined. RESULTS:

The frequency of NKT cells was lower in patients with SLE than in control

subjects. No such decrease was observed in the relatives of patients with

SLE or in patients with RA. High levels of IgG were observed in both

patients with SLE and their relatives, while low levels of IgM were observed

in these same groups. In relatives of patients with SLE, an inverse

correlation between the frequency of NKT cells and IgG levels was observed.

Moreover, raised levels of IgG in patients with SLE and their relatives and

high levels of IgG anti-dsDNA in patients were associated with low

frequencies of NKT cells.

CONCLUSION: These results suggest that NKT cells have an important role in

the regulation of IgG production, although NKT cells with invariant T cell

receptors may not necessarily be involved. NKT cells in the setting of SLE

could lack the cytokine stimulus from NK or other cells that is needed to

exert control on IgG production. Enhancement of NKT cell activity may

provide a novel basis for therapy in SLE.

PMID: 17195234

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve & db=PubMed & list_uids=1\

7195234

Not an MD