Mice harboring kinase-inactive IRAK4 on the lupus-prone Yaa background manifested blunted TLR signaling in macrophages and reduced glomerulonephritis, splenomegaly, serum anti-nuclear antibodies, numbers of splenic macrophages, total and TNF-α<sup>+</sup> dendritic cells, activated T- and B-lymphocytes, and lower TNF-α expression in macrophages compared with lupus-prone mice with functional IRAK4.
Tumor necrosis factor α (TNFα) levels, cell death, and cellular damage in BM from SLE patients, controls, and mice with pristane-induced lupus were analyzed using a morphometric technique and immunohistochemistry.
Treatment with anti-TNF agents is, however, controversial in SLE since induction of antinuclear antibodies, anti-dsDNA, anticardiolipin antibodies, and cases of drug-induced lupus have been observed in rheumatoid arthritis patients.
We have previously reported that lupus monocytes display distinctively differing patterns of C-reactive protein (CRP)-inducing cytokine interleukin (IL)-6, IL-1beta, and tumor necrosis factor (TNF)-alpha secretion when stimulated with either immune complexes (ICs) or lipopolysaccharide (LPS).
The PTPN22 C1858T polymorphism is associated with skewing of cytokine profiles toward high interferon-alpha activity and low tumor necrosis factor alpha levels in patients with lupus.
Since excessive B cell-activating factor belonging to the TNF family (BAFF) expression correlates with human and murine lupus, and BAFF signals B cell survival through BAFF-R, it is believed that excessive BAFF-R signaling can subvert B cell tolerance and facilitate lupus development.
The allelic frequencies of the TNFa polymorphic variant (TNF2) of seventy lupus patients were determined during follow-up at the Medical Clinic of the National University Hospital Malaysia by PCR-RFLP technique.
These findings demonstrate a physiological role for TNF in suppressing the emergence of autoreactive lymphocytes in the NZB model, and indicate that defective TNF function may be causative of the autoimmune and pathological phenomena in lupus.
We have analyzed the roles of tumor necrosis factor alpha (TNF-alpha) in human systemic lupus erythematosus (SLE) and murine models of lupus as well as in type 1 diabetes in NOD mice.