Immunological responses to respiratory syncytial virus infection in infancy

OBJECTIVES

To determine whether there is evidence of immunological responses in infants with respiratory syncytial virus (RSV) bronchiolitis by measuring inflammatory mediators in peripheral blood and, if found, whether these related to the severity of illness.

PATIENTS AND METHODS

Blood was taken from 94 children with RSV infection during the acute episode and 10 or more days later when the child was well. Control serum samples were obtained from well children of similar ages. Serum samples were assayed for mediators of lymphocyte activity (interleukin-4 (IL-4), soluble interleukin-2 receptor (sCD25), soluble intercellular adhesion molecule-1 (sICAM-1), eosinophil activity (eosinophil cationic protein) and neutrophil activity (myeloperoxidase). Symptoms were assessed as very mild (coryza only), mild (symptoms of lower respiratory tract infection), moderate (requiring nasogastric or intravenous fluids), and severe (requiring oxygen or ventilation).

RESULTS

IL-4 concentrations were at the lower limits of detection of the assay. The concentrations of sCD-25 were greater in samples from patients with acute illness than from convalescent patients and both were greater than in control samples. sICAM-1 concentrations were similar in samples from patients with acute illness and convalescent patients, but both were greater than in samples from controls. Eosinophil cationic protein concentrations were lower in samples from patients with acute illness than in those from convalescent patients; there was no difference between samples from convalescent and control patients. Myeloperoxidase concentrations were similar in all samples. There was no correlation between the severity of infection and the concentrations of any inflammatory mediators.

CONCLUSIONS

There is evidence of an inflammatory response in the peripheral blood of infants with acute bronchiolitis which may affect lymphocytes and eosinophils, but an association between this response and the severity of illness was not shown here.

Comparison of ribosomal DNA sites in Lolium species by fluorescence in situ hybridization

The position of the 18S-5.8S-26S and 5S rRNA genes have been physically mapped on the chromosomes of seven Lolium taxa. 18S-5.8S-26S sites were seen on two pairs of chromosomes in the inbreeding taxa. In the outbreeding taxa six sites were found in the L. multiflorum, seven in L. perenne and nine in L. rigidum var. rigidum. Two 5S sites were found in each of the taxa. In the inbreeders, the 5S sites were found adjacent to the 18S-5.8S-26S sites on chromosome 2. In L. multifiorum and L.perenne the 5S sites were on the short arm of chromosome 3. However, in L. rigidum var. rigidum the 5S rDNA site was found in either of the two positions.

Pharmacological treatment for antisocial personality disorder alcoholics: a preliminary study

A short time ago, we reported that a subgroup of hospitalized alcoholic men with comorbid antisocial personality disorder (ASP) seemed to benefit significantly from antidepressant medication at the end of a 6-month period in a double-blind, random assignment, placebo-controlled study. In a reanalysis of those data, we divided the ASP alcoholic group (n = 29) into those who did (n = 15) and who did not (n = 14) also satisfy DSM-III-R criteria for an additional current mood and/or anxiety disorder and then compared the 6-month outcomes of these two smaller subgroups. Despite the small ns, the results for most drinking outcome measures indicated: (1) that ASP alcoholics with a current mood/anxiety disorder improved significantly more with pharmacological treatment, relative to placebo; and (2) that ASP alcoholics with no current mood/anxiety disorder failed to respond differentially to pharmacological treatment over the 6-month period. These findings suggest a possibly useful and inexpensive approach to the long-term management of a very difficult-to-treat subgroup of men substance abusers.

Labelling telomeres of cereals, grasses and clover by primed in situ DNA labelling

Primed in situ DNA labelling (PRINS) labels the telomeres of Avena, Triticum, Secale, Hordeum, Lolium, Festuca and Trifolium when primers are used that correspond to the repeat unit of Arabidopsis telomeres. There are interstitial sites labelled in a Lolium x Festuca hybrid.

Analysis of the human serological immune response to a variable region of the attachment (G) protein of respiratory syncytial virus during primary infection

The serum antibody responses of babies to the variable carboxy-terminal region of the attachment (G) protein of respiratory syncytial virus (RSV) have been analysed using paired acute and convalescent sera from infants experiencing their first RSV infection with viruses of known genotype. The variable 84-85 carboxy-terminal amino acids of the G protein of six recent isolates of group A RSV were expressed in Escherichia coli as fusion proteins with glutahione S-transferase. About half the infants developed antibodies which recognised these fusion proteins. The patterns of response obtained in enzyme linked immunosorbant assays and immunoblotting assays were closely related to the infecting genotype.

A double-blind, placebo-controlled study of nortriptyline and bromocriptine in male alcoholics subtyped by comorbid psychiatric disorders

This double-blind, placebo-controlled, 6-month follow-up treatment study investigated the efficacy of bromocriptine and nortriptyline in attenuating drinking behavior and psychiatric symptoms in 216 male alcoholic patients subtyped by comorbid psychiatric disorder(s). Three well-defined subtypes were examined: alcoholism only, alcoholism + affective/anxiety disorder, and alcoholism + antisocial personality disorder. It was hypothesized that both medications would relieve negative affective symptoms associated with alcohol use and would be particularly effective for the affective/anxiety subgroup. Contrary to our predictions, the only significant effects found were with the antisocial personality disorder patients who were receiving nortriptyline. One interpretation of the results was that nortriptyline may have reduced impulsive drinking in the antisocial personality disorder subgroup by actions on serotonergic neurotransmission.

Impact of desipramine or carbamazepine on patient retention in outpatient cocaine treatment: preliminary findings

This is a preliminary report of a double-blind comparison of desipramine or carbamazepine to placebo among subjects participating in an outpatient cocaine treatment program. Sixty-five subjects were randomly assigned to one of the active drugs or placebo and followed until treatment completion or drop-out to determine if either drug enhanced retention in treatment and/or increased cocaine abstinence. There was no significant difference between carbamazepine or desipramine and placebo on either outcome measure in this preliminary analysis. While this is a preliminary report and does not take into account the heterogeneity of the patients in cocaine treatment, the results are consistent with those of other investigators and suggest that use of desipramine or carbamazepine may not offer any advantage in retaining cocaine-dependent patients in treatment.

SPECT regional cerebral blood flow alterations in naltrexone-precipitated withdrawal from buprenorphine

The effects of naltrexone-precipitated withdrawal from buprenorphine on behavior and regional cerebral blood flow (rCBF) were studied in 11 opiate-dependent patients. Patients initially received buprenorphine, 2 mg sublingually, every day for 7 days. They were then challenged sequentially with placebo and naltrexone, 25 mg orally, before single photon emission computed tomography with technetium-99m-d,l-hexamethyl-propylene amine oxime as tracer. Behavioral ratings of withdrawal severity were made before and after naltrexone/placebo administration. Naltrexone produced significantly greater signs and symptoms of opiate withdrawal than placebo. Analysis of variance revealed no significant regionally specific effect of naltrexone on rCBF ratios. Severity of withdrawal, however, showed a significant negative correlation with rCBF in the anterior cingulate cortex following naltrexone. These results are interesting as the anterior cingulate region has been implicated in the emotional component of pain and in opiate-induced analgesia.

Identification of parental and recombined chromosomes in hybrid derivatives of Lolium multiflorum × Festuca pratensis by genomic in situ hybridization

Genomic in situ hybridization (GISH) was used to identify Festuca chromatin in mitotic chromosomes of Lolium multiflorum (Lm) × Festuca pratensis (Fp) hybrids and hybrid derivatives. In two inverse autoallotriploids LmLmFp and LmFpFp, in situ hybridization was able to discriminate between the Lolium and Festuca chromosomes. In a third triploid hybrid produced by crossing an amphiploid of L. multiflorum × F. pratensis (2n=4x=28) with L. multiflorum (2n=2x=14), the technique identified chromosomes with interspecific recombination. Also, in an introgressed line of L. multiflorum which was homozygous for the recessive sid (senescence induced degradation) allele from F. pratensis, a pair of chromosome segments carrying the sid gene could be identified, indicating the suitability of GISH in showing the presence and location of introgressed genes. By screening backcross progeny for the presence of critical alien segments and the absence of other segments the reconstitution of the genome of the recipient species can be accelerated.

Intergenomic translocations and the genomic composition of Avena maroccana Gdgr. revealed by FISH

Fluorescence in situ hybridization (FISH) using total genomic DNA from putative diploid progenitors was used to confirm the presence of the A and C genomes in Avena maroccana. These results confirm cytological data that intergenomic translocations are present in A. maroccana.

Recurrence of Pallister-Hall syndrome in two sibs

We report the first definite sib recurrence of Pallister-Hall syndrome in a family without a cytogenetically visible chromosome abnormality. The father of these two sibs was born with nearly identical digital abnormalities and could represent either mild expression or gonosomal mosaicism for a dominant gene.

Kinetic analysis of the liver-type (GLUT2) and brain-type (GLUT3) glucose transporters in Xenopus oocytes: substrate specificities and effects of transport inhibitors

We have expressed the human isoforms of the liver-type (GLUT2) and brain-type (GLUT3) facilitative glucose transporters in oocytes from Xenopus laevis via injection of in vitro transcribed mRNA. As reported previously [Gould, Thomas, Jess and Bell (1991) Biochemistry 30, 5139-5145], GLUT2 mediates the transport of fructose and galactose, and GLUT3 mediates the transport of galactose. We have examined the effects of D-glucose, D-fructose and maltose on deoxyglucose transport in oocytes expressing GLUT2, and D-glucose, D-galactose and maltose on deoxyglucose transport in oocytes expressing GLUT3, and show that each sugar is a competitive inhibitor of transport. Moreover, D-glucose and maltose competitively inhibit fructose transport by GLUT2 and galactose transport by GLUT3, indicating that the transport of the alternative substrates for these transporters is likely to be mediated by the same outward-facing sugar-binding site used by glucose. Cytochalasin B is a non-competitive inhibitor of glucose transport by the well-characterized GLUT1 isoform. We show here that cytochalasin B is also a non-competitive inhibitor of the transport of deoxyglucose and alternative substrates by GLUT2 and GLUT3 expressed in oocytes. Km and Ki values for each substrate and inhibitor are presented for each isoform, together with further analysis of the binding sites for alternative substrates for these transporter isoforms.

Differential targeting of glucose transporter isoforms heterologously expressed in Xenopus oocytes

We have examined the subcellular distribution of three members of the human glucose transporter family expressed in oocytes from Xenopus laevis. Following injection of in vitro-transcribed mRNA encoding the transporter isoform to be studied, we have determined the subcellular localization of the expressed protein by immunofluorescence and by subcellular fractionation coupled with immunoblotting using specific anti-peptide antibodies. We have shown that both the liver-type (GLUT 2) and brain-type (GLUT 3) glucose transporters are expressed predominantly in the plasma membranes of oocytes, and in both cases high levels of glucose transport activity are exhibited. In contrast, the insulin-regulatable glucose transporter (GLUT 4) is localized predominantly to an intracellular membrane pool, and the levels of transport activity recorded in oocytes expressing GLUT 4 are correspondingly lower. The localization of the different transporter isoforms to distinct subcellular fractions mirrors the situation observed in their native cell type and thus demonstrates that oocytes may prove to be a useful system with which to study the targeting signals for this important class of membrane proteins. In addition, the determination of the amounts of the transporters expressed per oocyte together with a knowledge of their Km values has allowed us to estimate the turnover numbers of these transporters. Insulin was without effect on glucose transport in oocytes expressing any of these transporter isoforms. Microinjection of guanosine 5'-[gamma-thio]triphosphate into oocytes expressing GLUT 4 was also without effect on the transport rate.

Pancreatic beta-cells express a low affinity glucose transporter: functional consequences in normal and diabetic states

The application of molecular biology to the study of membrane transport proteins has led to a rapid advance in our understanding of the mechanisms behind the regulation of blood glucose levels. Moreover the demonstration of lesions in the expression of GLUT2 in the islets from diabetic models has provided a focus for research efforts aimed at addressing the defects responsible for the development and onset of both type I and perhaps type II diabetes. The recent demonstration that an 'artificial beta-cell' can be engineered from anterior pituitary-derived cell lines by transfection with both the insulin cDNA and the cDNA encoding GLUT2 represents a significant advance in the development of potential therapies for type I diabetes [24].

Analysis of the glucose transporter content of islet cell lines: implications for glucose-stimulated insulin release

Glucose transport across the plasma membrane of mammalian cells is mediated by a family of homologous proteins. Each glucose transporter isoform has a specific tissue distribution which relates to that tissue's demand for glucose. The beta-cells of pancreatic islets are known to express a distinct glucose transporter isoform, termed GLUT 2, which has a high Km for glucose. In this study, we examined the glucose transporter content of normal rat islets and three beta cell lines, beta-TC, HIT and RIN cells. We show that at the protein level, GLUT 2 is the only detectable transporter isoform in normal islets, and that all three cell lines also express detectable GLUT 2. In contrast, all three cell lines expressed high levels of GLUT 1, but this isoform was not detected in normal islets. Neither the native islets nor any of the cell lines expressed GLUT 3. The insulin-responsive glucose transporter GLUT 4 was detected at very low levels in beta-TC cells; to our knowledge, this is the only non-muscle or adipose cell line which expresses this isoform. We propose that the elevated level of GLUT 1 expression, together with a reduced expression of the high Km transporter GLUT 2, may account for the characteristic aberrant patterns of glucose-stimulated insulin release in cell lines derived from beta-cells.