Cerebral malaria in children: serum and cerebrospinal fluid TNF-alpha and TGF-beta levels and their relationship to clinical outcome.

This was a prospective study conducted at the Moi Teaching and Referral Hospital, Eldoret, Kenya. Twenty-three children admitted to the hospital with cerebral (CM) and 10 children with non-cerebral malaria (NCM) were studied. The aim of the study was to establish and compare levels of tumour necrosis factor (TNF-alpha) and transforming growth factor (TGF-beta1) in these children. Serum and cerebrospinal fluid (CSF) cytokine levels were assayed using ELISA kits. In serum, TGF-beta1 and TNF-alpha decreased over 5 days after admission to the hospital in both groups of patients with CM and NCM. In the CSF of cerebral cases the levels of TNF-alpha and TGF-beta1 were low and inversely related. Children in deeper coma had lower levels in serum of TGF-beta and higher levels of TNF-alpha than those in lighter levels of coma. The serum TNF-alpha levels in CM children were the same irrespective of the duration of illness before admission, but children with NCM who had been sick for a shorter duration before admission tended to have higher serum levels of TNF-alpha and higher levels of TGF-beta than those with a longer duration of illness before admission. In conclusion, this study shows that TNF-alpha and TGF-beta1 may not be useful in predicting the outcome for CM. They may, however, be useful in detecting children at risk of developing deep coma. TNF-alpha and TGF-beta levels were inversely related both in serum and CSF.

Measurement of tumor necrosis factor alpha and beta.

Tumor necrosis factor (TNF) a and b are multifunctional cytokines elaborated primarily by monocytes and macrophages (TNF-a) or T cells (TNF-b). Some cells that bind TNF-a or -b on their surface receptors lyse as a consequence of the binding reaction. This unit presents a protocol that employs TNF-sensitive, actinomycin D-treated murine L929 fibroblasts to quantify TNF activity in supernatants derived from cell cultures, serum samples, or cerebral spinal fluid. While the assay can measure picogram concentrations of human, rat, and murine TNF-ab, it cannot distinguish between the a and b forms of any species. A describes propagation and preparation of L929 fibroblasts.

TNF gene polymorphism and its relation to intracerebral production of TNFalpha and TNFbeta in AD.

OBJECTIVE: To analyze the extent of tumor necrosis factor-alpha (TNFalpha) and TNFbeta gene polymorphism in patients with AD and to relate it to intrathecal levels of these cytokines. METHODS: Analyses of TNFalpha and TNFbeta gene polymorphism were performed using PCR in 52 patients with AD and in 25 control subjects, and the levels of corresponding cytokines were analyzed using ELISA. RESULTS: Patients with AD displayed significantly higher intrathecal levels of TNFalpha, but not TNFbeta, compared with the control subjects. The levels of these cytokines did not differ significantly in patients displaying different alleles of the TNF gene. CONCLUSIONS: Results indicate that increased intrathecal production of TNFalpha in AD is preferentially controlled by environmental stimuli rather than genetic makeup.

Expression of tumor necrosis factor-alpha and transforming growth factor-beta 1 in cerebrospinal fluid cells in meningitis.

Meningitis is an acute inflammatory disease of the pia and arachnoid and the fluid in the subarachnoid space, in which a participation of cytokines can be expected. While tumor necrosis factor-alpha (TNF alpha) promotes inflammatory reactions, transforming growth factor-beta 1 (TGF beta 1) has antagonistic effects and suppresses the inflammation in the subarachnoid space. We investigated the protein concentration and mRNA expression of TNF alpha and TGF beta 1 in cerebrospinal fluid (CSF) by ELISA and intracellularly by non-radioactive in situ hybridization in 23 patients with bacterial or viral meningitis. A higher amount of both cytokines on protein and mRNA level, especially of TNF alpha, could be detected in bacterial infection. While an imbalance of both cytokines with a preponderance of TNF alpha- compared to TGF beta 1-mRNA was visible in CSF cells of patients with bacterial meningitis, a balance of TNF alpha- and TGF beta 1-mRNA or a higher expression of TGF beta 1-mRNA could be detected in viral meningitis. In the acute phase of the disease neutrophil granulocytes expressed more TNF alpha- and TGF beta 1-mRNA than lymphocytes and monocytes/macrophages, while these cell types were dominating the cytokine synthesis during the healing phase. These data indicate that immunomodulatory mechanisms take place in the CSF compartment itself, regulated by CSF cells in different but specific ways. In addition, TGF beta 1 seems to be involved in the down-regulation of the inflammatory activity and to be one factor in the cytokine network, which could contribute to a lower rate of complications and positive outcomes. Moreover this study favors the possibility to monitor the immunomodulatory mechanisms by non-radioactive in situ hybridization.

Multiple sclerosis: the proinflammatory cytokines lymphotoxin-alpha and tumour necrosis factor-alpha are upregulated in cerebrospinal fluid mononuclear cells.

Lymphotoxin-alpha (LT-alpha) and tumour necrosis factor-alpha (TNF-alpha) promote inflammation in autoimmune diseases and have been detected in the multiple sclerosis (MS) brain lesions and blood, suggesting these cytokines are also present in the cerebrospinal fluid (CSF). To study this, mononuclear cells (MNC) were examined for transcripts of LT-alpha and TNF-alpha, using in situ hybridization (ISH) with synthetic oligonucleotide probes. Most patients with MS had LT-alpha and TNF-alpha mRNA-expressing MNC in their CSF at mean frequencies of about 1/2800 cells for both cytokines. Numbers were dramatically higher than in the paired blood specimens. Control patients with other inflammatory neurological diseases (OIND) also had LT-alpha and TNF-alpha mRNA-expressing cells in CSF but at mean frequencies of only 1/36,000 and 1/18,000 cells, respectively. In blood, levels were similar in OIND and MS. To elucidate the influence of myelin antigen stimulation on LT-alpha and TNF-alpha expression, MNC were cultivated with or without myelin basic protein. Strongly elevated levels of MBP-reactive TNF-alpha mRNA-expressing cells were detected in the MS patients' CSF, in particular when examined during clinical exacerbations, as well as MBP-reactive LT-alpha mRNA-expressing MNC. No such patterns were observed in the OIND controls. The strong accumulation of LT-alpha- and TNF-alpha-producing cells and of MBP-reactive LT-alpha and TNF-alpha mRNA-positive cells in the immediate vicinity of the demyelinating process in MS patients implicates a role of these cytokines in the development of MS.