Depression of the generation of cell-mediated cytotoxicity by suppressor cells after surgery

The effects of surgical operation on the generation of cell-mediated cytotoxicity in mixed cell cultures were studied in patients with various carcinomas or benign lesions. Peripheral blood mononuclear cells from patients were cultured with B lymphoblastoid cell line Raji in mixed culture, and the induced cytotoxicity was measured by 51Cr release assay. In 15 patients with various carcinomas, the capacity of cells to generate cytotoxic cells was significantly depressed 1, 3 and 6 days after surgery, as compared to that before surgery. It returned to the pre-operative level by the 8th post-operative day. In eight patients with benign lesions, significant decrease in cytotoxic cell activity was observed 3 and 6 days after operation. At the 8th day, however, there was a significant increase in the generated cytotoxicity. The depressed generation of cytotoxic cells 3 days after surgery could be abrogated by removal of adherent cells from the responding cell population. This effect could be partially reconstituted by addition of separated, autologous adherent cells back to the responding non-adherent cell culture. These results demonstrate that suppressor cells, presumably monocytes, may be responsible for the depressed generation of cytotoxic cells after surgery.     

Synthesis of block copolymers from 1-chloro-1-octyne and other acetylenes through their sequential living polymerization by MoOCl4?n-Bu4Sn?EtOH

Block copolymerizations of 1-chloro-1-octyne (1-ClO) with several substituted acetylenes were examined by means of living polymerization. o-(Trifluoromethyl)phenylacetylene (o-CF₃PA), o-(trimethylsilyl)phenylacetylene (o-Me₃SiPA), 1-chloro-2-phenylacetylene (1-ClPA), p-butyl-o,o,m,m-tetrafluorophenylacetylene (p-BuF₄PA), and tert-butylacetylene (t-BuA) were used as comonomers, and the MoOCl₄-n-Bu₄Sn-EtOH (mole ratio 1:1:1) catalyst, which is known to effect living polymerization of substituted acetylenes, was employed. When o-CF₃PA and 1-CIPA were the comonomers in combination with 1-CIO, block copolymers were exclusively obtained in both orders of monomer addition. In the cases of o-Me₃SiPA and p-BuF₄PA as comonomers, the copolymerizations initiated from 1-CIO produced block copolymers selectively, whereas the homopolymers of o-Me₃SiPA and p-BuF₄PA also formed if the order of monomer addition was reversed. The pair of 1-CIO and t-BuA did not selectively yield block copolymers irrespective of the order of monomer addition. Thus, block copolymerization occurred between 1-CIO and monomers that show high “livingness” and close reactivities.     

HISTOPATHOLOGICAL STUDY ON PROGRESSIVE MUSCULAR DYSTROPHY—REPORT OF A CASE WITH AUTOPSY FINDINGS—

A typical case of the D uchenne type of progressive muscular dystrophy with autopsy findings was presented. Changes in the myocardial and smooth muscle of many organs were found, and the skeletal muscles also revealed florid changes.
Histopathological examination of the skeletal muscle was made in detail through light and electron microscopic observation.     

Existence of phenol oxidase in the argasid tick Ornithodoros moubata

Phenol oxidase (PO, EC 1.10.3.1) activity was detected in the hemolymph of the fourth instar nymphs of the argasid tick, Ornithodoros moubata, with peak levels corresponding to the days before the majority of the nymphs had molted, suggestive of a protective role of PO during the ecdysial phase. Higher PO activity was detected in plasma relative to the hemolymph and was negligible in hemocytes. The concentration of the hemolymph and plasma assayed clearly influenced the level of PO activity, and was significantly reduced ( P<0.005) after treatment with 1-phenyl-2 thiourea, a specific PO inhibitor. This is the first report of the existence of PO in the hemolymph and plasma of a soft tick species. The regulation of PO activity and its precise role in soft tick immunity, particularly during the ecdysial phase, are interesting and need to be examined further.     

Structural identification of an epitope of antigenic factor 5 in mannans of Candida albicans NIH B-792 (serotype B) and J-1012 (serotype A) as beta-1,2-linked oligomannosyl residues.

In previous articles, we reported the presence of phosphate-bound beta-1,2-linked oligomannosyl residues in the mannans of strains of Candida albicans serotypes A and B and Candida stellatoidea. To identify the antigenic factor corresponding to this type of oligomannosyl residue, a relationship between chemical structure and antigenic specificity in the mannans of C. albicans NIH B-792 (serotype B, B-strain) and C. albicans J-1012 (serotype A, J-strain) was investigated by using a combination of two-dimensional 1H nuclear magnetic resonance spectroscopy of H-1, H-2, and H-5 regions in the mannans and an enzyme-linked immunosorbent assay that employed concanavalin A-coated microtiter plates. It was shown in the present 1H nuclear magnetic resonance study that an examination of chemical shifts not only in the H-1 region but also in the H-5 region was useful for the quantitative determination of the phosphate-bound beta-1,2-linked oligomannosyl residues. In the enzyme-linked immunosorbent assay using concanavalin A-coated plates, it was revealed that, of factor sera 1, 4, and 5, only factor serum 5 showed a reactivity proportional to the densities of the beta-1,2-linked oligomannosyl residues of the mannan subfractions of different phosphate contents that had been prepared from the bulk B-strain mannan by DEAE-Sephadex chromatography. The above results indicate that the phosphate-bound beta-1,2-linked oligomannosyl residues, Manp beta 1----(2Manp beta 1----)n2Man (n = 0-5), correspond to antigenic factor 5.     

Mutation analysis of HNF-4 binding sites in the human glucose-6-phosphatase promoter

HNF-4, a member of the nuclear receptor superfamily, binds to HNF-4 response elements (HRE), consisting of a direct repeat of the hexameric half-sites spaced by 1 nt (direct repeat 1) and activates a number of genes, which play central roles in fatty acids and glucose metabolism. Glucose-6-phosphatase (G6Pase) catalyzes the terminal step in the gluconeogenic and glycogenolytic pathways. A previous study has shown that HNF-4 binds to two DR1s in the regions A (located between -266 and -234) and B (located between -306 and -274) on the human G6Pase promoter. We found that the region B contains the one more DR1 element, composed of the two half-sites, designated half-sites a and b, the latter of which overlaps with the previously identified DR1 consisting of two half-sites, designated half-sites b and c. In this study, electrophoretic mobility shift assay (EMSA) using point mutations in each half-site a, b, or c indicated that HNF-4 binds to the combination of half-sites a and b, but not to half-sites b and c. Furthermore, mutational analysis demonstrated that, in the context of the human G6Pase promoter, the half-sites a and b, but not the half-sites b and c, are required for the stimulatory effect of HNF-4. These results suggested that the DR1 element containing the half-sites a and b is a functional HRE that mediates the induction of hG6Pase promoter activity by HNF-4.     

Lymphokine-activated killer cell function of peripheral blood mononuclear cells, spleen cells and regional lymph node cells in gastric cancer patients.

Lymphokine-activated killer (LAK) cells generated by culture of peripheral blood mononuclear cells (PBMC), spleen cells (SPC) and regional lymph node cells (LNC) with IL-2 for 4 days were examined for their functional capabilities in 29 patients with gastric carcinoma. The cytotoxic activity of LAK cells induced from LNC was significantly lower than that from either PBMC or SPC, although there was no difference between PBMC or SPC. The induction of mRNA of interferon-gamma (IFN-gamma) or tumour necrosis factor-alpha (TNF-alpha) and the production of these cytokines in the non-adherent LAK cells from LNC were also significantly reduced compared with those from PBMC or SPC. Further, the LAK cells from LNC secreted significantly lower levels of these cytokines when stimulated with tumour target, Raji cells, although the production of these cytokines was markedly increased by stimulation with the targets in all three cell populations. Phenotypic analysis of each cell population revealed a decreased proportion of the cells mediating natural killer (NK) activity, including CD16+, CD56+, and CD57+ cells in LNC either before or after culture, although OKIa1+ and CD25+ cells were uniformly increased in all cell populations after culture. Changes in subpopulations of CD4+ and CD8+ cells in LNC were not apparently different from PBMC or SPC. These results indicated the differential reactivity of each lymphocyte population to IL-2 and the reduced LAK cell function of LNC compared with PBMC or SPC in patients with gastric carcinoma.