Effects of Maternal Ethanol Consumption on the Subsequent Development of Immunity to Trichinella spiralis in Rat Neonates

The immune response of rat pups to the intestinal parasite Trichinella spiralis was studied to determine if maternal pre-and/or postnatal ethanol consumption affected neonatal immune responses. Female rats were fed ethanol-containing (36% of calories) or pair-fed control liquid diets and include groups that were maintained on ethanol as follows: group 1, from day 1 of pregnancy through weaning and whose pups were then placed on ethanol to sacrifice; group 2, from day 1 of pregnancy through lactation; group 3, from day 1 of pregnancy through pup delivery; and group 4, from day 1 of lactation through weaning. A parallel group of animals was pair-fed isocaloric control diet until sacrifice. The pups of all litters were immunized orally with 500 L₁ (T. spiralis) larva 5 days after weaning. To examine the effects of maternal ethanol on primary immune responses, one-fourth of the pups from each litter were sacrificed on days 10 and 20 after immunization. To examine the effects on neonatal secondary immune responses, the remaining pups were challenged with 1,000 larva 30 days after the initial immunization and sacrificed either 3 or 8 days after challenge. At the time of sacrifice, blood samples were collected, the intestine removed to determine T. spiralis worm burdens, and suspensions of mesenteric lymph node (MLN) cells prepared. Intestinal worm counts and serum levels of anti-T. spiralis IgM and IgG antibodies, interleukin-2 (IL-2), and tumor necrosis factor (TNF) were determined. In vitro proliferation responses of MLN cells to T. spiralis antigen and to the mitogen concanavalin A (Con A) were also examined. Pups from groups 1 to 3 demonstrated significantly higher intestinal worm counts (decreased immunity) than the pair-fed controls at the day 20 primary immune response sacrifice, and pups from group 1 had significantly higher worm counts at day 3 after a secondary immune challenge. Pups of dams from groups 1, 3, and 4 had significantly lower IgM antibody titers at the day 20 primary immune response sacrifice. All experimental ethanol groups (1 to 4) demonstrated significantly lower IgG antibody titers than that observed in pair-fed control pups at the 20-day sacrifice. IgM antibody titers showed significant reductions for ethanol-treated groups at 3 and 8 days after T. spiralis secondary challenge. In addition, IgG antibody titers were also significantly reduced for all alcohol groups at 3 and 8 days during the secondary immune response. Serum IL-2 and TNF levels were significantly lower in all experimental ethanol groups (1 to 4) relative to pair-fed controls at day 20 during a primary immune response, and IL-2 levels at 3 days postchallenge were lower in groups 2 to 4 after a secondary immune challenge. MLN proliferation responses to antigen and Con A were significantly reduced in ethanol groups 1 to 3 and to Con A in group 4 at day 10 after a primary immune challenge. Ethanol group 3 pups also demonstrated a reduced response to antigen at day 20. For animals undergoing a secondary immune response, ethanol group 2 demonstrated a reduced response to antigen at day 3, whereas groups 2 and 4 showed increased reactivity to antigen at days 3 and 8 postchallenge. These results show that maternal ethanol consumption diminishes the capacity of neonates to respond to T. spiralis antigen and that the depressed immune response involves T-and B-cell–mediated reactions and also affects the production of certain cytokines. These results also suggest that the diminished immune responses are increased with longer periods of maternal and neonatal exposure to ethanol.     

Effects of elevated serum insulinlike growth factor-II on growth hormone and insulinlike growth factor-I mRNA and secretion

The insulinlike growth factors (IGF) appear to exert feedback control over their own production. In an effort to determine the physiologic mechanisms for this feedback modulation, we utilized a previously developed in vivo model in which rIGF-II secreting tumor cells are transplanted into immunodeficient rats to form IGF-II secreting tumors. The tumor-bearing rat have serum IGF-II concentrations sevenfold greater than those in controls (119 +/- 16 ng/mL [mean +/- SE] v 17 +/- 2 ng/mL, P less than .0001). Serum IGF-I concentrations were reduced among the tumor-bearing rats (438 +/- 42 ng/mL v 606 +/- 32 ng/mL, P = .002) and were negatively correlated with IGF-II concentrations (r = -.47, P = .025), suggesting that IGF-II suppressed the secretion of IGF-I. Increased serum IGF-II concentrations, however, did not affect basal growth hormone concentrations (tumor-bearing, 44 +/- 12 ng/mL; control 33 +/- 6 ng/mL, P = 0.96). The GH response to GH releasing factor was likewise similar in both groups. Moreover, pituitary GH mRNA level were not different in the two groups, suggesting that IGF-II does not have a significant effect on GH secretion in this in vivo model. There was no association between serum glucose and serum IGF-I or IGF-II concentrations. To examine the effect of IGF-II on IGF-I production from the liver, we measured IGF-I mRNA levels in a subset of animals. Despite these differences in serum IGF-I concentrations, the tumor-bearing rats did not have significantly lower liver IGF-I mRNA levels.(ABSTRACT TRUNCATED AT 250 WORDS)     

Ethanol Consumption Suppresses Cell-Mediated Inflammatory Responses and Increases T-Helper Type 2 Cytokine Secretion in Trichinella spiralis-Infected Rats

Alcohol consumption has been shown to be associated with immune suppression and immune modulation. In this study, the effects of ethanol ingestion on the host immune responses to Trichinella spiralis infection and the subsequent secretion of T-helper cell-associated cytokines were investigated in rats. At the early phase of T. spiralis infection, ethanol-fed animals showed decreased numbers of blood neutrophils and eosinophils, and a decreased secretion of interferon-γ (IFN-γ) by mesenteric lymph node cells, compared with pair-fed controls. Suppression of this early inflammatory response to infection in the ethanol-treated groups resulted in a slower rate of expulsion of intestinal adult worms and a higher fecundity rate for female worms, compared with pair-fed controls. A dramatic decrease in blood neutrophils in the ethanol-treated groups was also manifested on day 9 postinfection. At that time, mesenteric lymph node cells from the ethanol-treated groups secreted higher amounts of mast cell proliferation-enhancing activity, which has been shown to contain T-helper type 2-associated cytokines. At the later phase of infection (day 12 to 20 day postinfection), ethanol-treated animals contained higher numbers of blood eosinophils and secreted an increased amount of interleukin-5 and mast cell proliferation-enhancing activity, compared with pair-fed controls. Although there was a slight rise with time after infection, the level of serum corticosterone was not significantly increased in the ethanol groups. Therefore, it is not likely that the observed immune modulations caused by ethanol consumption, especially in the early phase of infection, is the effect of elevated levels of corticosterone in the circulation. The present study found that ethanol consumption suppressed the initial amount of interferon-γ secretion and inflammatory response, and may have directly or indirectly led to an enhancement of the secretion of T-helper type 2-type cytokines later in the primary immune response to T. spiralis infection.     

An undifferentiated variant derived from the human acute myelogenous leukemia cell line (KG-1)

A variant subline (KG-1a) of the human acute myelogenous leukemia (AML) cell line (KG-1) has been isolated. The cells retain the same constitutive markers as the parent line, including HLA antigens, isoenzymes, and karyotype. The cells from the subline are morphologically and histochemically undifferentiated blast cells, while the parent cells and several of its clones are at the myeloblast and promyelocyte stages of development. The variant cells do not respond to colony-stimulating factor (CSF), and they do not express the human la antigen, nor a recently characterized AML antigen. The parent KG-1 cells are stimulated to proliferate in the presence of CSF and the cells express the la and AML antigen. Variant AML cell lines, such as KG-1a, will be useful in vitro models for investigating cellular response to CSF and for studying antigen expression in leukemic cells.     

Randomized study of 13-cis retinoic acid v placebo in the myelodysplastic disorders

A double-blind, placebo-controlled randomized trial of 13-cis retinoic acid was performed to determine if the drug has a therapeutic effect in patients with myelodysplastic syndromes (MDS). Sixty-eight evaluable patients with MDS were randomized to receive a single, daily oral dose of either 13-cis retinoic acid (13-CRA, 100 mg/m2) or matching placebo. Treatment was continued, when possible, for a period of 6 months. Determination of response to treatment was based on clinical course, repeat bone marrow biopsies, and aspirates and blood counts (CBC) with WBC differential, platelet, and reticulocyte numbers at specified intervals. No significant difference was noted between the two treatment groups in response to test drug (P = .66). One patient (3%) in the 13-CRA group and two patients (6%) in the placebo group had a minor response. Approximately 30% of patients in both groups had progression of their disease, and progression-free survival was nearly identical. Greater than 90% of the patients receiving 13-CRA developed mild or moderate skin toxicity that was reversible with decreasing or discontinuing the drug. Our study did not find that 13-CRA exerts a beneficial therapeutic effect in patients with MDS.     

Deletions of the cyclin-dependent kinase inhibitor genes p16INK4A and p15INK4B in non-Hodgkin's lymphomas

The tumor suppressor genes p16INK4A and p15INK4B map to the 9p21 chromosomal locus and are either homozygously deleted or mutated in a wide range of human cancer cell lines and tumors. Although chromosome 9 abnormalities have been described in non-Hodgkin's lymphomas (NHLs), to date, the mutational status of these genes has not been determined for these malignancies. A total of five cell lines and 75 NHLs were examined for homozygous deletions or point mutations in the coding regions of both the p15 and p16 genes using Southern blot and/or polymerase chain reaction-single-strand conformation polymorphism analyses. Homozygous deletions of either the p16 gene or both the p15 and p16 genes were observed in one diffuse large B-cell lymphoma cell line and two uncultured lymphomas consisting of one large B-cell and one mixed T-cell lymphoma. In contrast, point mutations were not detected in either the cell lines or lymphomas. These results indicate that the rate of alterations in the p15 and p16 genes is low for lymphomas, but loss of p16 and/or p15 may be involved in the development of some lymphomas.     

N-ras gene point mutations in childhood acute lymphocytic leukemia correlate with a poor prognosis

Ras genes can be altered by point mutations at critical portions of their coding regions to acquire transforming ability in vitro. These point mutations have been detected in a variety of human malignancies. However, their relevance for the clinical and biologic behavior of the subgroups of patients exhibiting these mutations in unclear. We analyzed 100 patients with childhood acute lymphocytic leukemias (ALLs) for point mutations of exons 1 and 2 of all three ras genes (H-ras, K- ras, and N-ras) by polymerase chain reaction and a combination of oligonucleotide hybridization and direct DNA sequencing. A 6% incidence of N-ras gene mutations was detected, all of which occurred at different nucleotides of codons 12 or 13 of N-ras. When correlating presence of ras mutations with the clinical and biologic features and the clinical outcome of these cases, a significantly higher risk for hematologic relapse (P = .01) and a trend toward a lower rate of complete remission (P = .07) was noted. The two groups did not differ in any of the known high-risk factors of ALL. These results suggest that presence of an N-ras mutation in children with ALL may be an independent predictor for worse clinical outcome and therefore may have therapeutic implications; further studies to confirm these findings are required because of the small number of patients with N-ras mutations.     

Chronic myelocytic leukemia: eosinophils involved in the malignant clone

Chronic myelocytic leukemia (CML) is a clonal disorder involving neutrophil, monocyte, erythrocyte, and platelet precursors. In order to determine if the eosinophils are also involved in the leukemic clone, we purified the eosinophils from a woman heterozygous for the common electrophoretic variants of the G6PD gene. Only type B enzyme was demonstrable in the eosinophils, neutrophils, and red cells, but both A and B enzymes were found in the fibroblasts. The data provide evidence that the eosinophil is involved in the malignant clone.     

Are high doses of intracoronary adenosine an alternative to standard intravenous adenosine for the assessment of fractional flow reserve?

Background

Achievement of maximal hyperemia of the coronary microcirculation is a prerequisite for the measurement of fractional flow reserve (FFR). Intravenous adenosine is considered the standard method, but its use in the catheterization laboratory is time consuming and expensive compared with intracoronary adenosine. Therefore, this study compared different high, intracoronary doses of adenosine for the potential to achieve a maximal hyperemia equivalent to the standard intravenous route.

Methods

FFR was assessed in 50 patients with 50 intermediate lesions during cardiac catheterization. FFR was calculated as the ratio of the distal coronary pressure to the aortic pressure at hyperemia. Different incremental doses of intracoronary adenosine (60, 90, 120, and 150 μg as boli) and a standard intravenous infusion of 140 μg/kg/min were administered in a randomized fashion.

Results

Different incremental doses of intracoronary adenosine were well tolerated, with fewer systemic adverse effects than intravenous adenosine. At baseline, there were no significant differences for mean aortic and distal coronary pressure or heart rate in the different adenosine doses and routes. FFR decreased with increasing adenosine doses, with the lowest values observed with the 150-μg intracoronary bolus and 140-μg/kg/min dose of intravenous adenosine. All intracoronary doses, except the 150-μg bolus, resulted in mean FFR values that were significantly (P <.05) higher than FFR after the administration intravenous adenosine. Furthermore, 5 patients (10%) with a FFR value >0.75 and 3 subjects (6%) with a FFR value >0.80 who received a 60-μg intracoronary bolus reached a value below the cutoff point of 0.75 with the intravenous administration.

Conclusions

This study suggests a dose-response relationship on hyperemia for intracoronary adenosine doses >60 μg. The administration of very high intracoronary adenosine boli is safe and associated with fewer systemic adverse effects than standard intravenous adenosine. However, intravenous adenosine administration with 140 μg/kg/min produced a more pronounced hyperemia than intracoronary adenosine in most patients and should be the preferred mode of application for the assessment of FFR.