Species differences in the effect of pregnancy on lymphocyte cytokine production between human and rat

Abstract

In the present study, we evaluated whether lymphocyte cytokine production during human and rat pregnancy shifts toward T helper cell type 2 (Th2) cytokine production. Therefore, blood samples were taken during the follicular and luteal phase and during pregnancy in rats and humans. Whole blood was ex vivo-stimulated with phorbol 12-myristate 13-acetate and calcium ionophore and intracellular interferon-␥ (IFN-␥) and interleukin (IL)-4 production, and the percentage of cells in the various lymphocyte populations was measured using flow cytometry. Rats and humans adapted their immune responses to pregnancy but have different strategies: During human pregnancy, the percentage of lymphocytes producing IFN-␥ was decreased, and the percentage IL-4-producing lymphocytes was not affected. The rat adapts its immune response to pregnancy by decreasing the total number of the various lymphocyte populations, and the percentage of IFN-␥-or IL-4-producing lymphocytes was not affected or increased (% IFN-␥-producing cytotoxic lymphocytes). It is speculated that during rat pregnancy, there is no need to decrease the number of IFN-␥-producing lymphocytes, as in nonpregnant rats, the total number of IFN-␥-producing lymphocytes after stimulation is relatively low, and there is no necessity for a further decrease. In nonpregnant humans, the percentage IFN-␥-producing lymphocytes is much higher and probably dangerous for pregnancy, and therefore, this percentage needs to decrease during pregnancy. In conclusion, although the data from humans concur with the Th1/ Th2 paradigm, the data from rats do not concur with this paradigm. The present studies therefore challenge the classical Th1/Th2 paradigm during pregnancy. J. Leukoc. Biol. 78: 946 -953; 2005.

Effect of Feeding Probiotics on Rats' Immunity and Health Conditions during Pregnancy

“…Probiotic groups showed a first week reduction followed by a progressive increase during gestation to end with significantly higher percentage on postpartum, particularly in group one and three. The 4 /CD 8 ratios in all the groups were within the normal values (1.1 -2.9) with no significant changes. In conclusion probiotics, compared to the control, enhanced leucocytes production particularly group three (yogurt culture plus B. breve plus Lb.…”

“…After parturition, the percentages in the probiotic groups were insignificantly higher than before pregnancy (60%, 64% and 55% in groups 1, 2 and three, respectively) contrary to the control percentage which was lower than before pregnancy. The reduction in lymphocyte % on pregnancy was slight compared to literature which showed a significant reduction from 73% into 45% in rats [4]. Table 8 illustrates absolute counts of lymphocytes and phagocytes as calculated from lymphocyte percentage of leucocytes.…”

“…The percent of lymphocyte producing Ifn-γ and IL-4 cells are slightly increased in rats to give immune response of (Th1). But in humans, Ifn-γ producing cells decreased to give (Th2) cytokine humoral response, releasing IL-4, IL-5 and IL-10 to regulate antibody productions to strengthen humoral immunity [4]. The mechanisms on pregnancy by which the immune system modulates T-cell reactivity and production of cytokines were suggested to depend on several factors such as, production of estrogen and progesterone hormones, the presence of an immune suppressive factor (specific glycoprotein) and more important the existence of effectors-T-cell with regulatory functions (Tregs) carrying CD 25 + -T. These are potent suppressors of T-cells responses and can protect tissues from cell-mediated destruction.…”

“…The effect of probiotics feeding on leukocyte count, lymphocyte percent, phagocyte percent and lymphocyte CD 4 + -T and CD 8 + -T cells, serum lipid profile and body weight during gestation and postpartum were studied.…”

Ação da melatonina sobre a dinâmica sanguínea de ratas prenhes e sobre a histogênese do baço e do timo da prole

“…As interações entre a melatonina e o sistema imunológico têm sido bastante estudadas, e em praticamente todos os casos, a melatonina mostrou ter efeitos imunomoduladores da resposta imune (Esquifino et al, 2004;Faas et al, 2005). Entretanto, não é conhecido o papel desempenhando por esse hormônio durante a gestação, sobre a imunidade celular.…”