In Vivo and In Vitro Models of Demyelinating Disease: Endogenous Factors Influencing Demyelinating Disease Caused by Mouse Hepatitis Virus in Rats and Mice

Intracerebral inoculation of JHM virus (JHMV), the neuropathic strain of mouse hepatitis virus, into Wistar Furth, Wistar Lewis, and Fischer 344 rats at various ages indicated that Wistar Furth rats are more susceptible to the virus than are the other strains. Fischer 344 and Wistar Lewis rats were more resistant to inoculation at 2 and 5 days of age and completely resistant by 10 days of age. In contrast, Wistar Furth rats which were very susceptible at both 2 and 5 days of age remained susceptible until 21 days of age. Intracerebral challenge of an F1 cross between Wistar Furth and Wistar Lewis rats at 10 days of age indicated that resistance to JHMV infection is dominant. Cyclophosphamide treatment 28 days after intracerebral inoculation exacerbated an inapparent infection, leading to paralysis in eight of nine and death in six of nine Wistar Furth test rats. In such immunosuppressed animals, grey- and white-matter lesions were noted throughout the central nervous system, in contrast to the purely demyelinating lesions noted previously. Since rats, unlike mice, were not susceptible to disease after intracerebral injection with the serorelated viscerotropic strain MHV-3, we wished to extend our understanding of the neurological disease process elicited by the two viruses in rodents. For this reason, various mouse strains, including some with recognized immunodeficiencies, were challenged by different routes of inoculation. Intraperitoneal infection of nude and beige mice with JHMV indicated that lack of natural killer cell functions does not markedly enhance the susceptibility to virus, whereas T-cell activity appears to be essential for resisting infection. JHMV and MHV-3 replication in peritoneal macrophages from highly resistant A/J mice was reduced in comparison with that noted in macrophages from susceptible C57BL6/J mice. An initial intraperitoneal inoculation of JHMV was able to protect C57BL6/J mice against fatal intracerebral challenge within 3 days, whereas A/J mice remained susceptible beyond day 3. The protective effect did not appear to result from increased levels of circulating interferon, preceded elevation in serum JHMV-neutralizing antibody titers, and persisted for at least several weeks after intraperitoneal inoculation. Based on the combined studies described here and on previous work by us and others, it appears that the factors influencing the outcome of coronavirus disease in rodents are age at inoculation, route of challenge, genetic constitution of the virus and host, and competence of the immune system, particularly cellular immunity involving T-cells.     

Apolipoprotein B 3'-VNTR polymorphism in Eastern European populations

Apolipoprotein B 3' (3' ApoB) minisatellite polymorphism was studied in healthy unrelated individuals from the Russian Federation and the Republic of Belarus, in 10 populations from five ethnic groups: Russians, Byelorussians, Adygeis, Kalmyks and Yakuts. The analysis was carried out using PCR and electrophoresis followed by silver staining. Overall, 25 alleles of the 3' ApoB minisatellite, ranging from 25 to 55 repeats, were detected. Heterozygosity indices were high and varied from 0.73 to 0.84. The distributions of alleles of this minisatellite in the Caucasoid populations (Russians, Byelorussians and Adygeis) had a bimodal character, whereas that for Mongoloid populations (Kalmyks and Yakuts) had a unimodal distribution. Nei's genetic distances between the populations studied and some reference populations of Europe and Asia were estimated. Despite their allele distribution homogeneity, different East Slavonic ethnic groups were clearly resolved by multidimensional analyses. The East Slavonic and Adygei populations revealed a high similarity with European Caucasoids. The Mongoloid populations (Kalmyks and Yakuts) were considerably different from those of the European Caucasoid populations, but were similar to other Asian Mongoloid populations. The results demonstrate the variability of 3' ApoB minisatellite polymorphism not only in distant populations but also, to a certain extent, in genetically relative ones.     

Induction of a differentiated ciliated cell phenotype in primary cultures of Fallopian tube epithelium

Human Fallopian tubal epithelial cells in culture lose morphological features associated with the epithelium in situ and the extent to which they retain their in-vivo phenotype or function is unknown. In order to address this question, immunocytochemical markers were identified which distinguish secretory (HMFG2+, LhS28-) from ciliated (HMFG2-, LhS28+) epithelial cells in tissue sections of Fallopian tube. These markers were used to analyse the phenotype of tubal cells in vitro. Primary cultures of human tubal epithelial cells were seeded onto glass and grown to confluence before addition of oestradiol-17beta. In the absence of hormone, tubal epithelial cells expressed cytokeratins and nuclear receptors for oestrogen and progesterone and adopted a homogeneous (HMFG2+, LhS28-) secretory cell phenotype. Following the addition of oestradiol-17beta, a proportion of cells became positive for LhS28. The induction of a ciliated epithelial cell phenotype was confirmed by scanning electron microscopy, where on permeable collagen membranes, approximately one-third of tubal epithelial cells became ciliated in the presence of oestradiol-17beta. We suggest that in vitro, tubal epithelial cells adopt an immature secretory-like phenotype and that oestrogen can induce differentiation to a ciliated epithelial cell phenotype.      

Association between an interleukin-13 promoter polymorphism and atopy.

Several studies indicate genetic involvement of Th2 cytokines in allergic diseases. Interleukin (IL)-13 has been mapped to the cytokine cluster on chromosome 5q31-33, which has been associated with atopic conditions. Recently, an association was reported between the T allele in a promoter polymorphism in the IL-13 gene (C to T exchange) at position -1055 and allergic asthma in a population study in the Netherlands. This observation was apparently confirmed in a case-control study using probands and spouses from a Dutch asthma family study, but the polymorphism in that study was reported to occur at position -1111. In the present study, we established that this polymorphism is located at position -1024 relative to the ATG translation initiation codon, and investigated whether it confers a genetic predisposition to atopic conditions and the Th1 condition multiple sclerosis (MS) in Caucasian subjects. We confirmed the association between the IL-13 -1024TT genoype and inhalation allergy (P = 2.4E-02). By combining the data from the three studies, we demonstrated a strong association (P = 1.09E-05) between the IL-13 -1024 marker and inhalation allergy. Furthermore, we showed for the first time that this association also exists in atopic dermatitis (P = 2.0E-02). No association with MS was found.     

Primary Immunodeficiency Diseases in Latin America: First Report from Eight Countries Participating in the LAGID

The Latin American Group for Primary Immunodeficiencies, formed in 1993, presently includes 12 countries. One goal was to study the frequency of primary immunodeficiencies in various regions of the American continent and to enhance knowledge about these diseases among primary-care physicians, as well as allergist–immunologists. Important for this purpose was the development of a registry of primary immunodeficiencies using a uniform questionnaire and computerized database. To date, eight countries have collected information on a total of 1428 patients. Predominantly antibody deficiencies were reported in 58% of patients, followed by cellular and antibody immunodeficiencies associated with other abnormalities in 18%, immunodeficiency syndromes associated with granulocyte dysfunction in 8%, phagocytic disorders in 9%, combined cellular and antibody immunodeficiencies in 5%, and complement deficiencies in 2% of patients. The information gathered from this initial analysis of data will serve to expand the patient database to more areas within participating countries and to new countries and to increase collaboration toward better diagnosis and treatment of these diseases.     

Attitudes toward smoking cessation among men and women

Recent reports indicate that women are less successful than men in their attempts to quit smoking. Sex differences in attitudes toward smoking cessation were examined cross-sectionally in a sample of 447 smokers randomly selected from employees of 10 diverse Minnesota worksites and interviewed in early 1984. No sex differences were found in the percentage of smokers who had tried to quit at least once in the past; indeed, over four of five respondents reported prior attempts to quit. Yet compared to women, men were more interested in quitting. Women were less likely than men to perceive the health benefits of quitting and expressed more concern about weight gain and job pressures related to quitting. No significant sex differences were found in prior use of formal cessation services, which had been used by about one-fourth of these respondents. Yet compared to men, women appeared to rely on informal sources of support, such as encouragement from co-workers. These findings underline the importance of intervention programs targeting women and suggest strategies that might enhance the effectiveness of such programs oriented toward women.     

Clinical profiling of recombinant follicle stimulating hormone (rFSH; Puregon): relationship between serum FSH and efficacy

Single-dose and multiple-rising dose studies of recombinantfollicle stimulating hormone (rFSH) in hypogonadotrophic maleand female volunteers demonstrated that the rate of FSH absorptionafter i.m. injection is higher in men than in women. In theabsence of endogenous FSH, a correlation between serum FSH andbody weight became apparent. The elimination half-life of rFSHwas not different between the sexes and was comparable withurinary FSH. However, the in-vitro bio:immuno ratio of serumFSH was significantly higher after the administration of rFSHthan after urinary FSH. When rFSH was administered daily witha fixed dose, steady state levels were reached within 3-5 days.Serum FSH concentrations increased in a dose-dependent mannerwhen the daily dose was increased weekly over 3 weeks from 75to 225 IU. In hypogonadotrophic women, rFSH induced normal folliculargrowth whereas oestrogen synthesis was impaired. In women pituitarysuppressed by a high-dose oral contraceptive, the daily administrationof 150 IU rFSH for 1 week induced more and larger antral folliclesthan the same regimen with urinary FSH, whereas the serum immunoactiveFSH concentrations measured 24 h after each dosing were similar.It is concluded that even though equal or lower serum immunoactiveFSH concentrations were obtained following the administrationof rFSH compared with urinary FSH, circulating bioactivity FSHconcentrations were higher. Therefore, the conventional ideathat serum immunoreactive FSH correlates positively with themagnitude of the ovarian response should be reconsidered.