Effect of Surrogate Fostering on Splenic Lymphocytes in Fetal Ethanol Exposed Rats

This study evaluated the effects of surrogate fostering as a procedure to control for postnatal effects of ethanol on the maternal female that may indirectly affect the offspring. Effects of fostering on the development of splenic lymphocytes, as well as possible differential effects of fostering on female and male offspring were examined. Litters from prenatal ethanol exposed (E), pair-fed (PF), and ad libitum-fed control (C) condRions were fostered at birth to surrogate untreated dams who had given birth within the same 12-hr period, or were reared by their biological mothers. At 15 and 60 days of age, offspring from each of the conditions were sacrificed and splenic leukocytes were enumerated and analyzed for expression of differentiation antigens, using flow cytometry. At 15 days of age, fostering reduced the percentages of CD45RA⁺ and CD5⁺ cells in E compared with PF and in PF compared with C offspring, and reduced the percentage of CD4⁺ cells in E compared with C offspring. Fostering also had differential effects on E and C offspring, resulting in reduced percentages of CD45RA⁺ and CD5⁺ cells in fostered E compared with nonfostered E offspring, but increased percentages of CD45RA⁺, CD5⁺, and CD8⁺ cells in fostered C compared with non-fostered C offspring. Fostering also down-regulated CD5 antigen expression in E compared with C offspring and up-regulated CD4 antigen expression in C offspring compared with their nonfostered counterparts. At 60 days of age, E females overall had higher percentages of CD45RA⁺ cells compared with C females and higher percentages of CD4⁺ cells compared with PF and C females. Nonfostered E females had higher percentages of CD5⁺ cells than nonfostered C females. In contrast, E males overall had greater percentages of CD4⁺ cells compared with PF and C males. Among males, the percentage of CD5⁺ cells was increased in nonfostered E compared with nonfostered C, whereas the percentages of CD45RA⁺ and CD5⁺ cells were decreased in fostered E males compared with nonfostered E. For both females and males in the nonfostered condition there were no effects of prenatal ethanol treatment on differentiation antigen expression. However, after fostering, E females had higher CD45RA and CD5 antigen expression compared with PF and C females, whereas E males had increased CD4 antigen expression and C males had decreased CD5 antigen expression compared with their nonfostwed Counterparts. These data demonstrate that fostering at birth has differential effects on splenic lymphocyte populations in E, PF, and C offspring. Moreover, the effect of fostering varies with age and has differential long-term effects on female and male offspring. Thus, rather than serving as a control for indirect maternal effects of ethanol on offspring, fostering appears to be a treatment in itself and may actually confound the effects of prenatal ethanol exposure by differentially affecting E, PF, and C females and males.     

Effects of Prenatal Ethanol Exposure and Stress in Adulthood on Lymphocyte Populations in Rats

The present study was undertaken to assess the possible interactive effects of prenatal ethanol exposure and stress in adulthood on lymphocyte populations in rat offspring, and to examine differential vulnerability of males and females to these challenges. Male and female offspring from prenatal ethanol-exposed (E), pair-fed, and ad libitum-fed control conditions were exposed to a 3-week chronic intermittent stress regimen in adulthood. Animals were exposed to two of six different stressors daily, one each at random times in the morning and afternoon, with the same pair of stressors being repeated every 4 days. Following the 3-week stress period, lymphocytes from four compartments (peripheral blood, spleen, thymus, and cervical lymph nodes) were analyzed for expression of differentiation antigens. Data demonstrate that, whereas a number of the effects of prenatal ethanol on lymphocyte populations appeared to be nutritionally mediated, the additional challenge of exposure to stressors differentially affected animals exposed to ethanol prenatally and appeared to have effects primarily in male offspring. Stressed E males had a greater reduction in the number of pan T-cells in the thymus and peripheral blood, compared with nonstressed E males, but showed an increased peripheral blood pan T-antigen expression. Stressed E males also had reduced numbers of peripheral blood CD4⁺ T-cells and thymic CD4⁺CD8⁺ T-cells, compared with controls. In addition, several effects of stress were observed in animals in all three prenatal treatment groups, including decreased numbers of lymph node pan T- and CD4⁺ T-cells and decreased numbers of total peripheral blood lymphocytes in males, increased numbers of total splenic and thymic lymphocytes in females, and increased numbers of splenic CD8⁺ T-cells, as well as a decreased ratio of CD4⁺:CD8⁺ T-cells in the lymph node and spleen in both males and females. These findings indicate that, although exposure to chronic intermittent stress in adulthood may have marked effects on lymphocyte populations across all treatment groups, specific deficits in the immune system of fetal E animals may become apparent only when these animals are subjected to the additional challenge of stress. Moreover, male and female offspring may be differentially affected by the two challenges of ethanol and stress.     

Perinatal exposure to high dietary advanced glycation end products in transgenic NOD8.3 mice leads to pancreatic beta cell dysfunction

The contribution of environmental factors to pancreatic islet damage in type 1 diabetes remains poorly understood. In this study, we crossed mice susceptible to type 1 diabetes, where parental male (CD8⁺ T cells specific for IGRP_206-214; NOD8.3) and female (NOD/ShiLt) mice were randomized to a diet either low or high in AGE content and maintained on this diet throughout pregnancy and lactation. After weaning, NOD8.3⁺ female offspring were identified and maintained on the same parental feeding regimen for until day 28 of life. A low AGE diet, from conception to early postnatal life, decreased circulating AGE concentrations in the female offspring when compared to a high AGE diet. Insulin, proinsulin and glucagon secretion were greater in islets isolated from offspring in the low AGE diet group, which was akin to age matched non-diabetic C57BL/6 mice. Pancreatic islet expression of Ins2 gene was also higher in offspring from the low AGE diet group. Islet expression of glucagon, AGEs and the AGE receptor RAGE, were each reduced in low AGE fed offspring. Islet immune cell infiltration was also decreased in offspring exposed to a low AGE diet. Within pancreatic lymph nodes and spleen, the proportions of CD4⁺ and CD8⁺ T cells did not differ between groups. There were no significant changes in body weight, fasting glucose or glycemic hormones. This study demonstrates that reducing exposure to dietary AGEs throughout gestation, lactation and early postnatal life may benefit pancreatic islet secretion and immune infiltration in the type 1 diabetic susceptible mouse strain, NOD8.3.     

The Effect of Cold Stress on Lymphocyte Proliferation in Fetal Ethanol-Exposed Rats

Prenatal ethanol exposure and stress have each been shown to have significant effects on the immune system. This study examined the possible interactive effects of prenatal ethanol exposure and exposure to stress later in life on the immune system. Differential vulnerability to these challenges in female and male offspring was assessed. At 5 to 6 months of age, female and male offspring from prenatal ethanol-exposed (E), pair-fed (PF), and ad libitum-fed control (C) conditions were exposed to 0, 1, or 3 days of cold (4°C). At the end of the cold period, the proliferative response of splenic lymphocytes to the mitogens concanavalin A (Con A) and pokeweed mitogen (PWM) was assessed. The data demonstrate a significant interactive effect between prenatal ethanol exposure and cold stress in female offspring. After 1 day of cold stress, E females had significantly increased PWM-induced lymphocyte proliferation compared with PF and C females, and significantly increased Con A-induced lymphocyte proliferation compared with PF females. There were no differences in PWM or Con A-induced lymphocyte proliferation among E, PF, and C females after 0 or 3 days of cold stress, nor among E, PF, and C males on any test day. Regardless of prenatal treatment, females exposed to 1 or 3 days of cold had significantly greater basal plasma corticosterone levels than females not exposed to cold. In contrast, only E males exposed to 1 or 3 days of cold had significantly increased basal plasma corticosterone levels, compared with E males not exposed to cold; PF and C males showed no significant change in basal corticosterone after cold stress. These data demonstrate that, in response to the challenge of cold stress, changes in lymphocyte proliferation to PWM and Con A may occur selectively in E females. Moreover, the interactive effects of prenatal ethanol and cold stress may result in enhanced rather than suppressed immune responsiveness.     

Suppression of Immune Responsiveness: Sex Differences in Prenatal Ethanol Effects

Exposure to ethanol in utero results in changes in the offspring's developing immune system, including thymus lymphocyte subpopulation shifts and functional lymphocyte changes that persist in adult animals. The present study was designed to define further the extent of changes in the immune system that result from fetal ethanol exposure and to compare effects in male and female offspring. In adulthood, male and female offspring from Sprague-Dawley dams fed an ethanol-containing liquid diet (alcohol, A), an isocaloric liquid control diet (pair-fed, PF), or laboratory chow and water (control, C) during pregnancy were tested for several measures of immune competency. Prenatal ethanol exposure differentially affected male and female offspring. Fetal ethanol-exposed males exhibited a decrease in thymocyte number as well as a decreased splenic lymphocyte proliferative response to the T-cell mitogen, concanavalin A (Con A), with a concomitant decrease in recoverable blast cells, when compared with PF and C males. Further, the defect in T-cell proliferation of A males was not due to an inability to produce the critical growth factor, interleukin-2 (IL-2), but to an inability of lymphoblasts to utilize exogenous IL-2. Fetal ethanol-exposed females showed some suggestion of lower thymocyte counts and decreased splenic T-cell proliferative responses to Con A compared to PF and C females. For most of the immune measures, however, no significant differences occurred among A, PF, and C females. In utero ethanol exposure did not significantly alter spleen cell counts or IL-2 production, splenic B-cell proliferation to bacterial lipopolysaccharide (LPS), or thymocyte response to IL-2 in animals of either sex.(ABSTRACT TRUNCATED AT 250 WORDS)     

Fetal and neonatal exposure to nicotine disrupts ovarian function and fertility in adult female rats

Women born to mothers who smoked during pregnancy have been shown to have imparied fertility, although the mechanisms underlying this association are unknown. Nicotine administration in adult animals has adverse effects on the ovary and uterus; however, the effects of fetal exposure to nicotine on postnatal ovarian function have not been determined. The goal of this study was to assess the effect of fetal and neonatal exposure to nicotine on ovarian function and fertility of the offspring. Nulliparous female Wistar rats were given 1 mg·kg⁻¹·d⁻¹ nicotine bitartrate, subcutaneously for 14 d prior to mating, during pregnancy and throughout lactation until weaning. Measures of fertility, breeding success, and serum levels of ovarian steroid hormones in offspring were assessed at 4 and 6 mo of age. Fetal and neonatal exposure to nicotine significantly increased the time to pregnancy as the animals aged. Similarly, evidence of altered ovarian steroidogenesis in cluding increased serum progesterone concentrations and a decreased estrogen: progesterone ratio was observed in 6-mo-old animals. We conclude that fetal and neonatal exposure to nicotine results in delayed ovarian dysfunction in adult female offspring.     

Contribution of Thy1+ NK cells to protective IFN-γ production during Salmonella Typhimurium infections

IFN-γ is critical for immunity against infections with intracellular pathogens, such as Salmonella enterica. However, which of the many cell types capable of producing IFN-γ controls Salmonella infections remains unclear. Using a mouse model of systemic Salmonella infection, we observed that only a lack of all lymphocytes or CD90 (Thy1)⁺ cells, but not the absence of T cells, Retinoic acid-related orphan receptor (ROR)-γt–dependent lymphocytes, (NK)1.1⁺ cells, natural killer T (NKT), and/or B cells alone, replicated the highly susceptible phenotype of IFN-γ–deficient mice to Salmonella infection. A combination of antibody depletions and adoptive transfer experiments revealed that early protective IFN-γ was provided by Thy1-expressing natural killer (NK) cells and that these cells improved antibacterial immunity through the provision of IFN-γ. Further analysis of NK cells producing IFN-γ in response to Salmonella indicated that less mature NK cells were more efficient at mediating antibacterial effector function than terminally differentiated NK cells. Inspired by recent reports of Thy1⁺ NK cells contributing to immune memory, we analyzed their role in secondary protection against otherwise lethal WT Salmonella infections. Notably, we observed that a newly generated Salmonella vaccine strain not only conferred superior protection compared with conventional regimens but that this enhanced efficiency of recall immunity was afforded by incorporating CD4⁻CD8⁻Thy1⁺ cells into the secondary response. Taken together, these findings demonstrate that Thy1-expressing NK cells play an important role in antibacterial immunity.     

Effects of Maternal Alcohol Consumption on Milk and Blood Lymphocytes and IgG Antibody Levels from Trichinella spiralis-Infected Rats

Immunity to the intestinal parasite Trichinella spiralis can be transferred from the mother to the neonate during lactation. Previous studies in our laboratory showed that the passage of immunity to pups from ethanol-treated dams was depressed. This study examined the effect of ethanol consumption during pregnancy and lactation on the T. spiralis-associated immune components in milk and blood. Groups of female rats were fed either ethanol-containing or isocaloric liquid diets for 30 days before T. spiralis infection, mated and maintained on corresponding diets through pregnancy and lactation. Two-color flow cytometric analysis was performed for lymphocyte populations, enzyme-linked immunoabsorbent assay for specific IgG, and radial immunodiffusion assay for total IgG. The percentage of total T cells and their subsets, T helper cells and T cytotoxic/suppressor cells in milk and those in blood were similar between pair-fed and ethanol-treated animals. However, the percentage of natural killer cells in milk from ethanol animals was significantly reduced compared with the pair-fed group (33% vs. 54%). The percentage of activated or memory type T helper cell subset (OX22^?W3/25⁺) was significantly increased in the blood of the ethanol-treated group. Pair-fed animals showed higher T. spiralis-specific IgG antibody levels both in milk and blood compared with ethanol-treated animals. In ethanol-treated animals, specific IgG levels and total IgG concentration in milk were significantly lower than those in blood, whereas in pair-fed animals, only total IgG concentration in milk was lower than that in blood. This study indicates that ethanol consumption during pregnancy and lactation alters the maternal immune system. Decreased milk natural killer cells and depressed specific antibody levels in milk of ethanol-treated animals are possible contributing factors to the previously observed depressed lactational immune transfer to the pups.     

Antidepressant treatment with fluoxetine during pregnancy and lactation modulates the gut microbiome and metabolome in a rat model relevant to depression

ABSTRACT

Up to 10% of women use selective serotonin reuptake inhibitor (SSRI) antidepressants during pregnancy and postpartum. Recent evidence suggests that SSRIs are capable of altering the gut microbiota. However, the interaction between maternal depression and SSRI use on bacterial community composition and the availability of microbiota-derived metabolites during pregnancy and lactation is not clear.

We studied this using a rat model relevant to depression, where adult females with a genetic vulnerability and stressed as pups show depressive-like behaviors. Throughout pregnancy and lactation, females received the SSRI fluoxetine or vehicle. High-resolution 16S ribosomal RNA marker gene sequencing and targeted metabolomic analysis were used to assess the fecal microbiome and metabolite availability, respectively.

Not surprisingly, we found that pregnancy and lactation segregate in terms of fecal microbiome diversity and composition, accompanied by changes in metabolite availability. However, we also showed that fluoxetine treatment altered important features of this transition from pregnancy to lactation most clearly in previously stressed dams, with lower fecal amino acid concentrations. Amino acid concentrations, in turn, correlated negatively with the relative abundance of bacterial taxa such as Prevotella and Bacteroides.

Our study demonstrates an important relationship between antidepressant use during the perinatal period and maternal fecal metabolite availability in a rat model relevant to depression, possibly through parallel changes in the gut microbiome. Since microbial metabolites contribute to homeostasis and development, insults to the maternal microbiome by SSRIs might have health consequences for mother and offspring.     

Effect of maternal nicotine exposure on neonatal rat lung development: protective effect of maternal ascorbic acid supplementation

In previous studies it was shown that maternal nicotine exposure during pregnancy and lactation interfered with fetal and neonatal lung growth and development. It was suggested that the adverse effects of maternal nicotine exposure on the lungs of the offspring may be due to inadequate protection of these lungs against oxidants. Wistar rats were used in this study. After mating the rats were randomly assigned into 4 groups, namely a control group, a group receiving only nicotine, a group exposed to only vitamin C, and a group exposed to both nicotine and vitamin C. The aim of this study was, firstly, to determine the effect of maternal nicotine exposure (1 mg/kg body weight/day, subcutaneously) during gestation and lactation on the lungs of the offspring; secondly, to test whether the subcutaneous administration of vitamin C (0.5 mg/kg body weight/day) influences lung development; and, lastly, to determine whether subcutaneous administration of vitamin C will prevent the adverse effects of maternal nicotine exposure on lung development in the offspring. Morphologic and morphometric techniques were used to determine the effect of nicotine and vitamin C on lung development in the offspring on postnatal days 14, 21, and 42. The results showed that maternal exposure to nicotine only or vitamin C only resulted in a gradual deterioration of the parenchyma of the lungs of the offspring. These changes, which resembled microscopic emphysema, only became evident after the lungs of the offspring reached maturation. Those animals that were exposed to both nicotine and vitamin C via the placenta and mother's milk were less severely affected. It is also not advisable to use subcutaneous administration of vitamin C during gestation and lactation to prevent smoke- and nicotine-related effects on the developing lung, and other strategies should be investigated.     

Effective collaboration between marginal metallophilic macrophages and CD8+ dendritic cells in the generation of cytotoxic T cells

The spleen is the lymphoid organ that induces immune responses toward blood-borne pathogens. Specialized macrophages in the splenic marginal zone are strategically positioned to phagocytose pathogens and cell debris, but are not known to play a role in the activation of T-cell responses. Here we demonstrate that splenic marginal metallophilic macrophages (MMM) are essential for cross-presentation of blood-borne antigens by splenic dendritic cells (DCs). Our data demonstrate that antigens targeted to MMM as well as blood-borne adenoviruses are efficiently captured by MMM and exclusively transferred to splenic CD8⁺ DCs for cross-presentation and for the activation of cytotoxic T lymphocytes. Depletion of macrophages in the marginal zone prevents cytotoxic T-lymphocyte activation by CD8⁺ DCs after antibody targeting or adenovirus infection. Moreover, we show that tumor antigen targeting to MMM is very effective as antitumor immunotherapy. Our studies point to an important role for splenic MMM in the initial steps of CD8⁺ T-cell immunity by capturing and concentrating blood-borne antigens and the transfer to cross-presenting DCs which can be used to design vaccination strategies to induce antitumor cytotoxic T-cell immunity.     

Lack of Effects of Maternal Salt Intake on Blood Pressure of Offspring in Dahl Salt-Sensitive Rats

Inbred Dahl salt sensitive (S/JR) and salt resistant (R/JR) rats were used to look for effects of varying maternal intake of salt (NaC1) on the blood pressure of the offspring. Neither the blood pressure at weaning nor the blood pressure response to postweaning high salt diet of S/JR or R/JR rat pups was affected whether their mothers had eaten high salt (8% NaCl) or low salt (0.15% NaCl) diet during gestation. Similarly, maternal salt intake during lactation had no effect on the blood pressure of the offspring at weaning or the blood pressure response to salt feeding after weaning. Na⁺ was higher and K⁺ was lower in milk of S/JR compared to R/JR mothers during the last half of the lactation period, but dietary salt intake did not influence milk Na⁺ or K⁺. Previous cross-fostering experiments show that this strain difference in milk electrolytes does not influence S pups blood pressure. It is concluded that neither maternal salt intake nor the existing changes in milk Na⁺ have any influence on the blood pressure of Dahl salt sensitive rat pups in contrast to the marked effects of salt intake in these rats after weaning.     

Chronic Ethanol Exposure Alters Leukocyte Subsets in Repopulating Spleens, But Does Not Alter Negative Selection in Thymuses of Sublethally Irradiated Mice

Results from previous in vitro experiments in this laboratory suggested that ethanol may affect selection processes in the thymus. To determine whether ethanol allows escape of potentially autoreactive T-cell clones from negative selection, we fed ethanol to sublethally irradiated, young, adult C57BR mice during the time of thymic and splenic repopulation as a new model of human third trimester fetal alcohol exposure. The mice received a whole-body, sublethal dose (6 Gy) of gamma irradiation at 5 to 6 weeks of age. Feeding of a liquid diet providing 25% of calories as ethanol (EDC) or an isocaloric control liquid diet was begun 3 days after irradiation and was continued for 5 weeks. Each EDC mouse had 2 weight- and age-matched controls, 1 pair-fed (PF), and 1 fed ad libitum (AD LIB). Average blood alcohol concentrations (90 to 440 mg/100 ml) were higher than those reported previously for neonatal mice exposed to ethanol through lactation. At 5 weeks after irradiation, the EDC mice had lower total thymocyte numbers ( p < 0.05) and a higher proportion of CD4^- CD8^- thymocytes than either the PF or AD LIB mice ( p < 0.05), which is consistent with findings using in utero models of ethanol exposure. Ethanol exposure also altered the proportion of leukocyte subsets in repopulating spleens. B cells were the most sensitive to the detrimental effects of ethanol and, as a percentage of total nucleated cells in the spleen, B cells were decreased in the EDC group, compared with both the PF and AD LIB groups ( p < 0.05). C57BR mice normally delete by negative selection thymocytes bearing vβ17⁺ T-cell receptors. There was no discernible effect of ethanol exposure during thymic and splenic repopulation on the expression of Vβ17a on thymocytes and splenic T lymphocytes, indicating that ethanol does not affect negative selection.     

Maternal protein restriction induces early‐onset glucose intolerance and alters hepatic genes expression in the peroxisome proliferator‐activated receptor pathway in offspring

Aims/Introduction

Maternal undernutrition during pregnancy and/or lactation can alter the offspring''s response to environmental challenges, and thus increases the risk of the development of metabolic diseases at a later age. However, whether maternal protein restriction can modulate glucose metabolism in the early life of offspring is less understood. Furthermore, we explored the potential underlying mechanisms that illustrate this phenotype.

Materials and Methods

To test this hypothesis, we examined the offspring of C57BL/6J mice at weaning to determine the effects of feeding their mothers a low-protein diet or normal chow diet throughout pregnancy and lactation. Gene array experiments and quantitative real-time polymerase chain reaction were utilized to explore the altered hepatic genes expression.

Results

The offspring of dams fed a low-protein diet had a lower birthweight and bodyweight, impaired glucose tolerance, decreased insulin sensitivity, and decreased serum cholesterol at weaning. Using gene array experiments, 253 differentially expressed genes were identified in the liver tissues of the offspring between the two groups. Bioinformatic analyses showed that all differentially expressed genes were mapped to 11 pathways. We focused on the ‘peroxisome proliferator-activated receptor signaling pathway,’ because peroxisome proliferator-activated receptors have emerged as central regulators of glucose and lipid homeostasis. Quantitative real-time polymerase chain reaction was utilized for the validation of genes in the pathway.

Conclusions

A maternal low-protein diet during pregnancy and lactation promotes early-onset glucose intolerance in the offspring mice, and the altered hepatic genes expression in peroxisome proliferator-activated receptor signaling pathway could play role in regulating this phenomenon.     

Influence of Ethanol Consumption on Immune Competence of Adult Animals Exposed to Ethanol In Utero

Ethanol consumption results in significant changes in the immune system of experimental animals and humans. Previous work by ourselves and others has established that in utero exposure to ethanol results in alterations in the immune system of the offspring that persist into adult life. The present study was designed to determine if prenatal exposure to ethanol results in increased vulnerability to the immunosuppressive effects of ethanol consumption in adulthood. Male and female Sprague-Dawley offspring were selected in adulthood from prenatal ethanol (E), pair-fed (PF), and ad libitum-fed control (C) groups, and given either an ethanol-containing liquid diet or were pair-fed an isocaloric liquid diet without ethanol for 30 days. At the end of the 30-day feeding period, lymphocyte responses to the mitogens concanavalin A (Con A) and lipopolysaccharide, and to interleukin-2 (IL-2) were tested using in vitro assays. The results of this study support and extend previous data demonstrating long-term adverse effects of prenatal ethanol exposure on T-cell responses to mitogens, and provide further evidence that deficits seem to be more robust in male than in female offspring. Prenatal E males showed reduced T-lymphocyte proliferation to Con A and T-lymphoblast proliferation to IL-2, compared with their prenatal PF and C counterparts, regardless of whether they were exposed to the ethanol or the control diet in adulthood. In addition, T-lymphoblast proliferation to IL-2 was suppressed in prenatal E, compared with prenatal C, females exposed to control diet in adulthood. This is the first report of a deficit in T-cell aspects of immunity in E females, although it appears that this deficit may have been partially mediated by nutritional effects. A second major finding in this study is that consumption of ethanol diet in adulthood in itself had significant immunosuppressive effects on T-cell responses in both males and females. However, contrary to our expectation, previous exposure to ethanol in utero did not exacerbate the changes in immune responsiveness that were observed after adult ethanol consumption.     

Utilization of interleukin-2 gene transfer in local immunotherapy of cancer

It has been previously found that local administration of Balb/c plasmacytoma cells transformed and made non-tumorigenic by insertion of the cloned murine interleukin-2 (IL-2) gene induced regressions of a variety of murine tumours including the original Balb/c plasmacytoma X63-Ag8.653 growing in syngeneic mice. The tumour-inhibitory effect of the plasmacytoma cells transformed by IL-2 cDNA and designated as X63-m-IL-2 was due to their high constitutive production of IL-2. Here we show that admixture of syngeneic spleen cells to the X63-m-IL-2 transformants substantially (P<0.025) increased the antitumour efficacy of the transformants. Balb/c spleen cells co-cultivated with X63-m-IL-2 cells in vitro yielded predominantly Thy 1.2⁺, CD3⁺, LFA-1⁺ lymphocytes, cytolytic for the X63-Ag8.653 plasmacytoma as well as for other murine tumours, including the X63-m-IL-2 target cells.Abbreviations IL-2 interleukin-2 - LAK lymphokine-activated killer - NK natural killer - HPRT hypoxanthine phosphoribosyl transferase - HAT hypoxanthine/aminopterin/thymidine     

Fetal Alcohol Effects in Rats Exposed Pre- and Postnatally to a Low Dose of Ethanol

Wistar rats were exposed pre- and/or postnatally to a low dose of ethanol (1 g/kg of body weight of dams/day) via maternal peroral intubation. This dose significantly increased the mortality rate (23 to 32% vs. 7% in controls) in offspring exposed to ethanol during pregnancy, with a continued postnatal exposure having no additional effect. However, offspring cross-fostered to dams that had been exposed to ethanol only during gestation (the offspring themselves never being directly exposed to ethanol) displayed an even greater (59%) mortality. Growth of the offspring was initially delayed, but 9 weeks after birth their body weight reached that of the controls. The two-way active avoidance test showed an impairment, compared with the controls, of learning and memory in both male and female adolescent (9-week-old) rats, as well as in male (but not in female) 5-month-old rats born of dams exposed to ethanol during gestation and lactation. In the group of male rats treated prenatally and postnatally with ethanol, 60% were "poor learners," compared with 33% in the control group. Results suggest that ethanol at a dose of 1 g/kg/day administered to dams during gestation and lactation produced growth and behavioral changes in the offspring.     

Indomethacin decreases resistance of gastric barrier to disruption by alcohol

Using a canine chambered stomach preparation, the effects of three 30-min exposures of the gastric mucosa to 20% ethanol in 100 mN HCl on gastric mucosal barrier disruption and ulcer formation were assessed. The interval between exposures was 30 min. Following an initial exposure to 20% ethanol, the net fluxes of H⁺, Na⁺, and K⁺ ions and perfusate volume induced by a second and third exposure of the gastric epithelium to this damaging agent were significantly reduced. Only minimal ulceration was observed following the first exposure which did not worsen with subsequent exposure to ethanol. If indomethacin was given intravenously either before or immediately after the first ethanol exposure, recovery of barrier function was significantly lessened after this challenge, and the resistance to barrier disruption was significantly decreased during the two subsequent exposures to ethanol when compared to experiments in which mucosa was exposed to 20% ethanol without concomitant administration of indomethacin. In addition, marked mucosal ulceration was observed during the second and third ethanol exposures if indomethacin was given. these studies suggest that the first alcohol challenge may have elicited the synthesis and release of tissue prostaglandins and thereby enhanced resistance of the gastric mucosa to subsequent challenge by this damaging agent. When prostaglandin synthesis was blocked by indomethacin, the increased resistance to gastric injury did not occur.This work was supported by research grant AM 25838 from the National Institute of Arthritis, Metabolism and Digestive Diseases.     

Effects of Prenatal Ethanol Exposure on Hypothalamic-Pituitary-Adrenal Function Across the Estrous Cycle

Background: Rats prenatally exposed to ethanol (E) typically show increased hypothalamic‐pituitary‐adrenal (HPA) responses to stressors in adulthood. Importantly, prenatal ethanol may differentially alter stress responsiveness in male and female offspring, suggesting a role for the gonadal hormones in mediating the effects of ethanol on HPA activity. We investigated the role of ethanol‐induced changes in hypothalamic‐pituitary‐gonadal (HPG) activity in the differential HPA regulation observed in E compared to control females across the estrous cycle. Methods: Peripheral hormones and changes in central neuropeptide mRNA levels were measured across the estrous cycle in adult female offspring from E, pair‐fed (PF) and ad libitum‐fed control (C) dams. Results: Ethanol females showed normal estrous cyclicity (vaginal smears) but delayed sexual maturation (vaginal opening). Both HPG and HPA activity were differentially altered in E (and in some cases, PF) compared to control females as a function of estrous cycle stage. In relation to HPG activity, E and PF females had higher basal and stress estradiol (E₂) levels in proestrus compared to other phases of the cycle, and decreased GnRH mRNA levels compared to C females in diestrus. Further, E females had greater variation in LH than PF and C females across the cycle, and in proestrus, only E females showed a significant LH increase following stress. In relation to HPA activity, both basal and stress CORT levels and overall ACTH levels were greater in E than in C females in proestrus. Furthermore, AVP mRNA levels were increased overall in E compared to PF and C females. Conclusions: These data demonstrate ethanol‐induced changes in both HPG and HPA activity that are estrous phase‐specific, and support the possibility that changes in HPA activity in E females may reflect differential sensitivity to ovarian steroids. E females appear to have an increased HPA sensitivity to E₂, and a possible shift toward AVP regulation of HPA activity. That PF were similar to E females on some measures suggests that nutritional effects of diet or food restriction played a role in mediating at least some of the changes observed.