Ba salam!
National Library of Medicine MEDLINE Database
TITL: Suppression of cytotoxic T lymphocyte activity by gamma/delta T cells in
tumor-bearing mice.
AUTH: Seo N; Egawa K
ORGA: Department of Tumor Biology, University of Tokyo, Japan.
CITE: Cancer Immunol Immunother 1995 Jun; 40 (6): 358-66
LANG: ENG; English
ABST: Spleen cells derived from tumor-bearing mice prove useful for the
elucidation of the mechanism determining how tumor cells evade cytotoxic T
lymphocytes (CTL) in tumor-bearing hosts. Our data indicate that inactive CTL
or precursor CTL specific for tumor antigens are present among lymphocytes of
tumor-bearing mice. However, their activity is inhibited by a soluble factor
produced by other cells present in the same source. Inhibition of the
cytolytic reaction was also detected in the culture supernatant of spleen
cells obtained from normal mice, precultured in the presence of tumor cell
culture supernatant and interleukin-2 (IL-2). Cell-depletion and
cell-purification studies let us conclude that cells that produced the
CTL-inhibitory factor (CTL-IF) were gamma/delta T cells. The gamma/delta T
cells that were activated in vivo in tumor bearers were able to produce
CTL-IF after isolation and in vitro culture. Maximum activation of
gamma/delta T cells was achieved by antigenic stimulation and by suppression
of cells that interfered with the activation of gamma/delta T cells. CTL-IF,
which was assayed by use of CTL clones, did not show antigen specificity.
Inhibition depended on a relatively heat- and acid-stable, but alkali-labile
molecule with a molecular mass of less than 10 kDa. The latter
characteristics imply that CTL-IF does not resemble any of the known
lymphokines produced by gamma/delta T cells. These observations emphasize the
crucial role of the gamma/delta T cells in the escape of tumor cells from the
attack of tumor-specific CTL. (AUTHOR)
MJTR: Immunotherapy. Mammary Neoplasms, Experimental IM. Mammary
Neoplasms, Experimental TH. Receptors, Antigen, T-Cell, gamma-delta IM.
T- Lymphocytes, Cytotoxic IM.
MNTR: Animal. Antigens, CD8 IM. Antigens, Neoplasm IM. Biological
Factors IM. Biological Factors PD. Lymphocyte Transformation.
Lymphokines BI. Lymphoma, T-Cell IM. Lymphoma, T-Cell TH. Mice.
Mice, Inbred C3H. Mice, Inbred C57BL. Spleen CY. Spleen ME.
Support, Non-U.S. Gov't. Tumor Cells, Cultured. JOURNAL ARTICLE
RNUM: 0 (lymphocyte proliferation inhibitory factor); 0 (Antigens, CD8); 0
(Antigens, Neoplasm); 0 (Biological Factors); 0 (Lymphokines); 0 (Receptors,
Antigen, T-Cell, gamma-delta)
GEOT: GERMANY
IDEN: ISSN: 0340-7004. JOURNAL-CODE: CN3. ENTRY-DATE: 950907. JOURNAL-
SUBSET: M X. IM-DATE: 9511.
ACCE: 95354180
(c) Elsevier Science B.V. All Rights Reserved.
EMBASE (THE EXCERPTA MEDICA DATABASE) TITLE: Some factors affecting
aflatoxin production on lupine, chick pea and nut sedge by Aspergillus
parasiticus
AUTHOR: Daw Z.Y.
SOURCE: Microbiology Department, Faculty of Agriculture, Cairo University,
Cairo, Egypt
JOURNAL: CHEM. MIKROBIOL. TECHNOL. LEBENSM. 1989 12/1 (24-30)
CODEN: CMTLB
ISSN: ---------
LANGUAGE: English
SUMMARY-LANGUAGE: German
ABSTRACT: Lupine, chick pea and nut sedge are, at higher moisture content,
widely used as food in Egypt. The possibility of such commodities to support
growth and aflatoxin production by Aspergillus parasiticus was investigated.
Aflatoxins were produced on all sterilized substrates, and chick pea
supported maximum aflatoxin production after 14 days of incubation followed
by lupine and nut sedge. However, non-sterilized substrates furnished a
little aflatoxin formation, as they were not detected in lupine and only very
trace amounts of B [1] and G[1] were found on nut sedge. Chick pea provided
also little amounts of B[1] (4 (mu)g/25 g) and G[1] (6 (mu)g/25 g) while
aflatoxins B[2] and G[2] were not detected. Experiments were also done to
determine the influence of favoured additives (NaCl, some spices such as hot
pepper and cumin, lemon juice and mixture of all) on growth and aflatoxin
production by Aspergillus parasiticus. Such materials at higher
concentrations controlled aflatoxin formation. The inhibitory effect of these
materials on aflatoxin formation can be generally arranged in the sequence:
mixture of all > NaCl > cumin > hot pepper > lemon juice.
EMTAGS: 0502 Biological model; 4031 North africa; 0777 Nonhuman; 0763 Fungus
EMTREE-CODE: D5.80.90.590; D1.20.440.445; J2.60.10; K2.10.50
MEDICAL-DESCRIPTOR: aflatoxin; spice; sodium chloride; lemon juice; biological
model; egypt; lupin; chickpea
EMCLAS: 052 - Toxicology
CAS REGISTRY NUMBER: 1402-68-2; 7647-14-5
EMBASE-NUMBER: 89054040
In article <Pine.LNX.3.96.981028143030.24065A-100000 at pearl.sums.ac.ir>,
gharam at sums.ac.ir (Marjan Gharagozloo) wrote:
-----------== Posted via Deja News, The Discussion Network ==----------
http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own
