Hiromi Tagoh

Elevation of serum interleukin 6 prior to acute phase proteins on the inflammation by surgical operation

Serum levels of interleukin 6 (IL-6) and acute phase proteins were measured in patients who underwent surgical operation. Elevation of IL-6 preceded that of acute phase proteins, indicating that the measurement of serum IL-6 may be helpful for the early detection of an inflammatory state.

Elevated levels of interleukin-6 in serum and cerebrospinal fluid of HTLV-I-associated myelopathy/tropical spastic paraparesis

A significant elevation of interleukin-6 (IL-6) level was observed both in serum (mean 0.455 +/- 0.251) and in cerebrospinal fluid (CSF) (mean 0.043 +/- 0.016) obtained from 13 patients with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) when compared to that of either asymptomatic carriers (mean 0.181 +/- 0.074 and 0.021 +/- 0.015, respectively) or controls (mean 0.208 +/- 0.119 and 0.021 +/- 0.015, respectively). The differences were statistically significant between HAM/TSP and asymptomatic carrier for serum (P less than 0.05) or CSF (P less than 0.01). The correlation indexes between serum IL-6 and anti-HTLV-I antibody titers in serum and CSF were 0.61 (P less than 0.06) and 0.67 (P less than 0.05), respectively. Both the cell count and protein level in CSF correlated with CSF IL-6 activity at 0.68 (P less than 0.01) and 0.56 (P less than 0.05), respectively. The results demonstrate that IL-6 may contribute to the production of anti-HTLV-I antibody, and signs of slight inflammation are present in the central nervous system in HAM/TSP.

A new highly sensitive immunoassay for cytokines by dissociation-enhanced lanthanide fluoroimmunoassay (DELFIA).

Non-isotopic immunoassays for human tumor necrosis factor alpha (TNF alpha) and human interleukin-6 (IL-6) were established by employing the dissociation-enhanced lanthanide fluoroimmunoassay (DELFIA) system based on the time-resolved fluoroimmunoassay technique with europium-labeled antibody. Compared to enzyme-linked immunosorbent assays and bioassays, the sensitivity and range of measurement were significantly increased by applying the DELFIA systems to TNF alpha and IL-6. TNF alpha was measurable from 100 fg/ml to 10 ng/ml with the TNF alpha-DELFIA and IL-6 was measurable from 100 fg/ml to 1 ng/ml with the IL-6-DELFIA.

Stromal Cells and Cytokines in the Induction of Recombination Activating Gene (RAG) Expression in a Human Lymphoid Progenitor Cell

The activation of recombination activating genes (RAGs) plays critical roles in the V(D)J gene recombination machinery and lymphocyte repertoire formation. However, the regulation of RAG gene expression in humans as well as animals is poorly understood. We show that RAG gene expression is activated in a human lymphoid progenitor cell line (FL8.2.4.4) by coculturing them on a bone marrow-derived stromal cell line (PA6) in the presence of cytokines. The RAG transcripts become detectable in 12 hours after initiation of culture, and the increased level is sustained at 24 hours. Among the cytokines, IL-3, IL-6, and IL-7, but not IL-2, IL-4, SCF, GM-CSF induces RAG activation. IL-3, IL-6, and IL-7 exert their effect synergistically on RAG activation. A cognate interaction between FL8.2.4.4 cells and PA6 stromal cells seems to be prerequisite for RAG activation. RAG transcripts are inducible in FL8.2.4.4 cells when cocultured on paraformaldehyde fixed-PA6 stromal cells in the presence of cytokines. These data indicate that two separate signals are both required for induction of RAG activation in lymphoid progenitors; one from the cell surface molecule(s) on stromal cells, and the other from recombinant cytokine(s). The expression of RAG mRNA in FL8.2.4.4 cells is concomitant with induction of recombinase activity. Thus, this system may provide a useful means for further understanding of the mechanisms controlling RAG activation and lymphocyte development in human system.

Purification and characterization of an allergenic monomeric hemoglobin from a chironomid distributed worldwide, Polypedium nubifer

The Pol n component MV, a potent experimental allergen for mice, was purified to homogeneity from extracts of a chironomid distributed worldwide, Polypedium nubifer (PN). The Pol n I component MV was shown to have cross-reactivity to hemoglobins (Hb) derived from all species of chironomids tested. Determination of the amino acid sequence of the first 37 N-terminal residues revealed that it had 30-59% homology to Hb of an European chironomid, Chironomus thummi thummi, which had been known as an important allergen for humans. By Western blot analysis, we showed that sera from asthmatic patients, which had positively reacted to the extract of the adult PN midge, bound to the purified Pol n I component MV. Furthermore, using rabbit polyclonal antibodies raised against synthetic polypeptides corresponding to the N-terminal residues, it was demonstrated that the N-terminal amino acid sequence between position 15 and 35 contained antigenic epitope(s) for human IgE. The results indicate that the Pol n I component MV is an allergen for human beings as well as for mice, and useful as a diagnostic tool for chironomid allergy.

Establishment of highly sensitive and wide-ranged immunoassay for TNF.ALPHA. by DELFIA.

Non-isotopic immunoassay for the human tumor necrosis factor α (TNFα) was established by employing the dissociated enhanced lanthanide fluoroimmunoassay (DELFIA) system, based on the timeresolved fluoroimmunoassay (TR-FIA) technique utilizing the europium-labeled antibody. In comparison with enzyme-linked immunosorbent assay and bioassay, the sensitivity and range of measurement could be significantly increased by applying the DELFIA system to TNFα.Biological samples, including serum, may affect some of the immunoassays. We overcome the serum influence to the measurement of TNFα by DELFIA, Percent recovery of additional TNFα in each diluted serum was determined, then the sliding standard curve of each serum sample was mathematically calculated from the recovery. Finally corrected TNFα amount was detected by using the sliding standard curve. We suggest that more accurate, sensitive and wide ranged TNFα immunoassay has been established by DELFIA with some revising calculation.