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The present recovery rate of brain tumors (20% of solid tumors in children) is 50%. Besides the progress made in neurosurgery and radiotherapy, those of chemotherapy have indisputably had an impact on the improvement of the rate of recovery. Protocols in use differ according to the histologic type of the tumor (astrocytoma, glioma, medulloblastoma). Indications for therapeutic trials for phase II and III tumors will require a longer period of follow-up as well as strict analysis of the result.

The analysis of Phase II trials with regard to brain tumors in children, aiming to test the activity of 1 drug or a combination of drugs is not easy, due to the following reasons: poor selection of patients (clinical and pathological heterogeneity), not always rational choice of the drugs and mostly, variability of the criteria and the methods used to assess the tumor response. When using a single drug, the current most efficient agents seem to be: cisplatinum, carboplatin, cyclophosphamide and etoposide, while nitroso-ureas have not been strictly studied. When using polychemotherapy, the best results have been obtained with the "8 drugs in 1 d" regimen. The most chemo-sensitive tumors are: medulloblastomas, primitive neurectodermal tumors, pinealoblastomas; high grade ependymomas and astrocytomas have been studied less in children than in adults. Present and future strict organisation of Phase II trials in brain tumors is compulsory in order to select the active agents, and to establish the best modalities of administration. The need to assess chemotherapy not only in refractory or relapsing patients, but also at diagnosis in high-risk patients is emphasized (after incomplete surgery and before radiotherapy).

A 4-month old infant developed an immediate and proven systemic allergic reaction to mercurothiolate. The acute accident occurred while an intracaval catheter was being treated with a dry-frozen heparin which excipient contains mercurothiolate. This conservative agent is present in numerous pharmaceutical preparations for topical and systemic use.

We have previously shown (L. Leclercq et al., Proc. Nat. Acad. Sci. 1984, 81:6491) that the supernatants of activated T helper cells can stimulate resting B cells to proliferate and to express early activation markers. The corresponding activity has been called B Cell Activating Factor or BCAF. Here we show that BCAF-containing supernatants can induce resting B cells to produce immunoglobulins of all isotypes as measured by enzyme linked immunoabsorbent assay. The isotype pattern obtained is similar to the one obtained when TH cells are cocultured with unprimed resting B cells. Furthermore, BCAF-containing supernatants induce IgG switches as measured by the secretion of IgG3, IgG1, IgG2a and IgG2b immunoglobulin by cell sorted surface IgG- resting B cells. These investigations confirm that BCAF-containing supernatants can act on resting B cells.

In order to determine the effect of parenteral antibiotherapy on the fecal flora in patients with profound and prolonged granulocytopenia, we initiated a prospective study of 62 cases of autologous bone marrow transplantation following high-dose chemotherapy. All patients were children from 2 to 18 years old, isolated in a protective environment, receiving a diet low in viable microbial content but no oral non-absorbable prophylactic antibiotics to decontaminate the gastrointestinal tract. Bacteriological analysis of fecal flora was conducted at least once a week before and during parenteral antibiotherapy, administered at the first greater than 38 degrees C febrile episode in these granulocytopenic patients (granulocyte count less than 0.5 X 10(9)/l). The 58 evaluable patients fell into three groups with regard to the systemic antibiotherapy: group A (n = 16): moxalactam + mezlocillin; group B (n = 15): moxalactam + tobramycin; and group C (n = 27): cefotaxime plus gentamicin. Fecal flora suppression was observed in 51/58 cases (88%) (group A: 15/16, group B: 13/15, group C: 23/27). It always occurred within 5 days of initiating parenteral antibiotherapy and persisted in 88% of the 51 patients over the whole period of systemic antibiotherapy. During the latter, fecal recolonization was observed in seven cases (12%), always by Enterobacteriaceae sensitive to the prescribed systemic antibiotherapy, never responsible for septicemia. Since parenteral antibiotherapy alone was able to suppress the gastrointestinal tract flora, the effects of this treatment should be considered in all trials of digestive tract decontamination.

An unusual family of cDNA clones homologous to human p55 IL-2R sequences was isolated from the murine HT-2 Th cell line. These clones were mapped, partially sequenced, and compared with previously published human and mouse IL-2R sequences. They appear to consist of various combinations of exons and introns, suggesting that they are derived from p55 IL-2R mRNA precursors. The configuration of exons in the splicing intermediates indicates that the murine and human gene organizations are similar and that the 3' end of intron 3 is well conserved between the two species. RNA mapping experiments using nuclear, cytoplasmic, and total RNA and probes derived from various parts of the p55 IL-2R gene support and extend the sequence data. They indicate that detectable amounts of immature p55 IL-2R mRNA are found specifically in the cell nucleus of the HT-2 cell line. Similar data were obtained for the Th cell clone 52.3 and the cytotoxic T cell line CTLL. All these results indicate that the T cell nucleus contains significant amounts of immature p55 IL-2R mRNA.

In the present study, the "8 drugs in 1 day" regimen was tested in 54 children: 27 relapses (brain and/or spinal and/or meningeal sites), 10 refractory progressive diseases, 13 macroscopic residual tumors after partial excision and/or radiotherapy; in 4 cases, this regimen was prescribed as first line treatment. The response rate (complete and partial remission) was 46%. Results were very encouraging in medalloblastomas with a response rate of 76.5% whereas in brain stem gliomas it was only 23% and 33% in other astrocytomas. Immediate toxicity, mainly hematological, was very moderate. These results justify to propose this regimen as adjuvant chemotherapy, mostly in medulloblastomas and to plan other similar trials, using the most active drugs which seem presently to be alkylating and platinum-derived agents.