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Biomedical subjects

N M Kouttab

Publications and source records attributed to N M Kouttab.

26 records · Page 2Linked to original sources
PubMed1976

Suprresion of in vitro lymphocyte stimulation in mice by uterine and placental extracts.

The effects of uterine extracts from virgin mice and uterine and placental extracts from mice at various stages of gestation on lymphocyte stimulation in vitro were compared. Placental and uterine extracts from mice in gestation, at 1% final concentration by volume, caused marked depression of lymphocyte reactivity to phytohemagglutinin-P (PHA) and to allogeneic cells in two-way mixed leukocyte cultures (MLC). An equivalent concentration of uterine extract from virgin mice caused slight depression of uterine extract from virgin mice caused slight depression of lymphocyte reactivity. Suppression was most of lymphocyte reactivity. Suppression was most marked with uterine extracts of mice at 15 days of gestation. At least two factors of different m.w. in uterine and placental extracts were responsible for suppression of lymphocyte reactivity. The higher m.w. fraction, present in small amounts in the uteri of virgin mice, was markedly increased in uteri of pregnant mice. This fraction contained immunoglobulin G (IgG). These factors may be involved in a protective role for the fetus from rejection by the mother as an allograft, thus assuring successful pregnancy.

Animals↗
PubMed1975

Oncornaviral protein modulation in mouse uterine tissue by estrogen (38467).

Treatment of ovariectomized NIH Swiss mice with estrogens elevated the level of the murine leukemia virus group specific protein and the activity of an RNA-directed DNA polymerase in the uterus. The extent that these markers were raised was dependent on the relative biological potency of the estrogen and on the time interval following treatment. Increases in the levels of both viral marker proteins were evident within 24 hr of treatment and were highest at 48 hr. Subsequently, viral protein levels declined to pretreatment levels.

Animals↗
PubMedDate not supplied

Production of human B and T cell growth factors is enhanced by thymic hormones.

The thymic preparations thymosin fraction 5 (TF5) and synthetic thymosin alpha 1 (T alpha 1) were examined for their ability to enhance growth factor production by human peripheral blood mononuclear cells (PBMC). The results showed that both TF5 and T alpha 1 were capable of enhancing the production of a B cell growth factor (BCGF-12kD) and T cell growth factor (TCGF; IL-2). Enhancement by T alpha 1 could be obtained at 100-200-fold lower concentrations than that seen with TF5. In contrast, no enhancement of growth factor production was obtained with control preparations of non-thymic tissue extracts at any concentrations used. It was observed that stimulation of BCGF-12kD and IL-2 was most significantly obtained when the PBMC were activated with lectin. Furthermore, no direct effect of thymic hormones on test B and T cells was observed. These observations provide the first direct evidence that production of B cell growth factors can be enhanced by thymic hormones. In addition, these studies suggest that thymic hormones may regulate B cell responses by acting on mature activated T lymphocytes.

B-Lymphocytes↗