Adoptive immunotherapy of a mouse colon carcinoma with recombinant interleukin-2 alone or combined with lymphokine-activated killer cells or tumor-immune lymphocytes

Summary We have used a BALB/c colonic adenocarcinoma (C-26) to evaluate the therapeutic potential of recombinant interleukin-2 (rIL-2) at high and low dosages in combination with or without lymphokine-activated killers (LAK) or tumor-specific, immune lymphocytes in either an adjuvant spontaneous or an artificial metastasis system. Most (80%) of the mice that underwent s.c. C-26 tumor excision were shown to die of spontaneous metastasis with lung involvement by 1–4 months after excision. Postsurgical systemic treatment with low-dose rIL-2 (3 × 10⁴ U/day, i.p.) increased the survival rate to 31% as compared to 21% (not significant) in excised controls while administration of high-dose rIL-2 (8 × 10⁴ U/day) led to 53% survival (P <0.01). Both LAK cells and C-26-tumor-immune lymphocytes given during rIL-2 treatment significantly increased the effects of rIL-2 at the low but not at the high-dose, with tumor-immune effectors resulting in the highest percentage (63%) of cures. When mice bearing 3-day artificial lung metastases of C-26 cells were treated with low- or high-dose rIL-2, in combination with or without LAK or tumor-immune lymphocytes, a highly significant reduction or abrogation of the number of lung foci was observed with all treatments, including those involving or tumor-immune lymphocytes alone. Assessment of survival benefit in these mice, however, showed survival prolongation, with 20% cures achieved by low-dose rIL-2 alone and up to 65% cures by LAK in combination with low-dose rIL-2. In this system of artificial metastasis high-dose rIL-2 alone increased the survival time but failed to cure the animals, and the addition of LAK was ineffective whereas that of tumor-immune lymphocytes led to 80% cure. These results suggest that tumorimmune lymphocytes are more effective than LAK when combined with rIL-2 and that caution is necessary in extrapolating findings obtained in artificial metastasis models.     

Lithium Stimulation of Membrane-Bound Phospholipase C from PC 12 Cells Exposed to Nerve Growth Factor

LiCl stimulated the formation of inositol monophosphate in PC12 cells that had been exposed to nerve growth factor (NGF) for 4-5 days. Half-maximal accumulation was observed at approximately 8 mM LiCl. Stimulation of formation of inositol bisphosphate plus inositol trisphosphate was half-maximal at approximately 1 mM LiCl. With membranes isolated from PC12 cells differentiated with NGF, the hydrolysis of added phosphatidylinositol 4,5-bisphosphate (PIP2) was stimulated by LiCl in a biphasic manner, with the first stimulation half-maximal at approximately 0.7 mM and the second half-maximal at approximately 15 mM LiCl. The apparent Km for PIP2 was lowered in the presence of 1.1 mM LiCl from approximately 200 to approximately 70 microM. Membranes from cells grown in the absence of NGF did not respond to LiCl. Although observations with intact cells are difficult to interpret without ambiguity, the results obtained with isolated membranes support our interpretation of the stimulatory action of lithium in the intact PC12 cells.     

Stimulation of Inositol Incorporation into Lipids of PC 12 Cells by Nerve Growth Factor and Bradykinin

The effects of bradykinin (BK) and lithium on the phosphatidylinositol cycle were examined in PC12 cells cultured for 20 h in the presence [PC12(+)] or in the absence [PC12(-)] of nerve growth factor (NGF). BK (1 microM) induced a small stimulation of the incorporation of myo-[2-3H]inositol into the lipids of PC12(-) cells and a three- to fourfold stimulation of such incorporation into the lipids of PC12 (+) cells. About 15 h of incubation with NGF and greater than 10 min of incubation with BK were needed for maximal stimulation of inositol incorporation by BK. In the presence of 25 mM LiCl, BK stimulated the inositol monophosphate levels nine-fold in PC12 (-) and 30-fold in PC12 (+) cells. After incubation for 20 h with NGF, an increased binding of [3H]BK to the PC12 (+) cells was observed at 4 degrees C. Exposure of the cells for 30 min to 25 mM LiCl enhanced the effect of BK on the inositol incorporation into total inositol lipids, especially in PC12(+) cells. In these cells, LiCl in the presence of BK also increased several-fold the intracellular levels of inositol bisphosphate and inositol trisphosphate.     

Influence of HLA genotype on birth weight of patients with Turner syndrome

Summary Growth failure starting before birth is a common characteristic in Turner syndrome, and its pathogenesis is still not completely explained. Experiments performed in mice and rats to test whether a genetic disparity between mothers and offspring and maternal immunological status have any influence on litter size have demonstrated that allogenic litters are significantly larger in size than genetically compatible ones. Studies in humans have given contrasting results, but some authors have found that heterozygosity at enzyme loci and in blood groups is positively correlated with intrauterine growth. HLA class I and II polymorphisms were defined in 53 patients with Turner syndrome and in their parents, and lymphocytotoxic antibody detection was performed in 36 mothers. These data were related to the patients' birth weight. The frequency of the HLA-B16 allele in patients with a birth weight > 10th centile was significantly higher in comparison with those < 10th centile. HLA antigen sharing was present in 43 couples (81.1%). Mean birth weight was 2934 ± 472 g in patients without HLA antigen parental sharing and 2721 ± 529 g in those whose parents shared HLA antigens. The mean birth weight of the 10 patients whose parents do not share HLA antigens was significantly higher than that of the patients with parental HLA–B+DR sharing (P < 0.05) and not significantly higher than in those patients with parental HLA sharing at other HLA loci. Patients whose parents shared B+DR antigens also had significantly smaller birth weights than those with B and A+B+DR sharing (P < 0.025 and P < 0.025). No significant difference in mean birth weight was found in relation to other parameters, such as mother-child histocompatibility, HLA homozygosity and lymphocytotoxic production in the mothers.     

1H- and13C-NMR spectroscopic studies of lipid extracts of the red algaGracilaria longa

Lipid extracts of the red algaGracilaria longa were studied by¹H- and¹³C-NMR spectroscopy. Peaks in the¹³C-NMR spectra attributable to sterols, chlorophylls and carotenoids allowed free and acylated cholesterol, chlorophylla and lutein to be identified as the most abundant components of these classes. A content of 0.5 ± 0.1 μmoles of total cholesterol/g wet alga was estimated from the¹H-NMR spectrum, which also allowed the determination of the phosphatidylcholine/total lipid molar ratio (9.5 ± 0.5%). The¹³C-NMR spectroscopic experiments provided information on the position of the double bonds on the fatty acid residues. A comparison between NMR spectra of lipid extracts obtained for wet and dried alga showed that the alga undergoes both a dramatic peroxidation and some glycolipid degradation during the drying process.