Antigenic specificities of bursal and thymic lymphocytes in the chicken

Bursal and thymic antigenic specificities have been shown in the chicken in an immune adherence assay using cross-absorbed rabbit antisera.     

Cutaneous unresponsiveness to Mycobacterium bovis BCG in intravenously infected mice.

Mice injected with 1 mg (about 1 X 10(7) CFU) of Mycobacterium bovis BCG in the footpad showed high levels of delayed-type hypersensitivity (DTH) to BCG antigens and a continuous increase in circulating specific anti-immunoglobulin G (IgG) antibodies throughout a 6-week observation period. In contrast, mice injected intravenously with a 1-mg dose failed to mount a DTH and showed a depression in antibody production at week 5 postinfection. A dose-response study revealed that an optimum dose of BCG, when injected intravenously, can induce a small but significant DTH response. The delayed cutaneous unresponsiveness in intravenously infected mice lasted at least 6 weeks and was not antigenically specific, in that it depressed the DTH response to Corynebacterium parvum. No simple relationship existed between levels of DTH and the amount of circulating anti-IgG antibodies. Splenectomy and treatment with a high dose of cyclophosphamide before infection, although greatly reducing the humoral response, did not reverse the BCG-induced unresponsiveness nor enhance levels of DTH in mice infected in the footpad. It is concluded that the intravenous infection of mice with BCG exerts a nonspecific inhibitory effect on delayed-type immune reactions by the induction of some type of suppressor mechanisms that are resistant to cyclophosphamide.     

A BALB/c congenic strain of mice that carries a genetic locus (Ityr) controlling resistance to intracellular parasites.

BALB/c.DBA/2 Idh-1b-Ityr-Pep-3b congenic mice were developed by introgressively backcrossing the Idh-1b and Pep-3b markers of DBA/2 mice onto the BALB/c pi mice. This introduced a 30-centimorgan chromosome 1 segment of DBA/2 chromatin that contained the Ityr gene. BALB/c.DBA/2 Idh-1b-Ityr-Pep-3b mice were resistant to in vivo infections by Salmonella typhimurium, Mycobacterium bovis, and Leishmania donovani.     

Diagnostic value of anti-Saccharomyces cerevisiae and antineutrophil cytoplasmic antibodies for inflammatory bowel disease: high prevalence in patients with celiac disease

Both celiac disease and inflammatory bowel disease (IBD) are characterized by chronic diarrhea and the presence of distinct (auto)antibodies. In the present study we wanted to determine the prevalence of serological markers for inflammatory bowel disease, i.e., perinuclear antineutrophil cytoplasmic antibodies (pANCA) and/or anti-Saccharomyces cerevisiae antibodies (ASCA), in 37 patients with biopsy-confirmed celiac disease (Marsh IIIb/c). The majority of the patients was positive for IgA (auto)antibodies typically associated with celiac disease, i.e., antiendomysium antibodies (EMA) (86.5%), antigliadin antibodies (AGA) (73%), and antirecombinant human tissue transglutaminase antibodies (rh-tTGA) (86.5%). Four patients with selective IgA deficiency could be identified by analyzing EMA, AGA, and rh-tTGA for the IgG isotype. The prevalence of pANCA and ASCA, markers that are used for IBD, was unexpectedly high in our cohort of patients with celiac disease: 8 patients were positive for pANCA (IgG) and 16 patients were positive for ASCA (IgG and/or IgA). These results indicate that the presence of pANCA or ASCA in the serum of patients with chronic diarrhea does not exclude celiac disease. A prospective study is required to determine whether pANCA and/or ASCA identify patients at risk for developing secondary autoimmune disease.     

Control of single-joint movements in deafferented patients: evidence for amplitude coding rather than position control

Two deafferented patients and several control subjects participated in a series of experiments to investigate how accurate single-joint movements are programed, spatially calibrated, and updated in the absence of proprioceptive information. The deafferented patients suffered from a permanent and severe loss of large sensory myelinated fibers below the neck. Subjects performed, with and without vision, sequences of forearm supinations and pronations with two temporal delays between each movement (0 s and 8 s). Overall, the lack of proprioception did not yield any significant decrease in movement accuracy when vision was available. Without vision, the absence of proprioceptive afferents yielded (1) significantly larger spatial errors, (2) amplitude errors similar to those of control subjects, and (3) a significant drift when an 8-s delay was introduced between two successive movements. Subjects also performed, without vision, a 20 supination followed by a 20 pronation that brought back the wrist to the starting position. On some trials, the supination was blocked unexpectedly by way of a magnetic brake. When the supination was blocked, subjects were already on the second target and no pronation was required when the brake was released. The defferented patients, unaware of the procedure, always produced a 20 pronation. These data confirm that deafferented patients were not coding a final position. It rather suggests that they coded an amplitude and translated the spatial distance between the two targets in a corresponding force pulse. Overall, the results highlight the powerful and key role of proprioceptive afferents for calibrating the spatial motor frame of reference.     

Prenatal diagnosis of classic hemophilia.

Prenatal diagnosis of classic hemophilia (hemophilia A) in mid-trimester was achieved by means of immunoradiometric assays for factor VIII on fetal plasma and amniotic-fluid mixtures obtained by fetoscopy. Samples were analyzed from six male fetuses at risk for severe hemophilia and from nine control fetuses for which fetoscopy was carried out to attempt prenatal diagnosis of other genetic disorders. The factor VIII coagulant-antigen values for the control (non-hemophilic) samples were 17 to 94, and the factor VIII related-antigen concentrations were 50 to 155 U per deciliter. Three of the fetuses at risk for hemophilia had factor VIII values in the control range, and these infants were normal at birth. The other three fetuses had low concentrations of factor VIII coagulant antigen but normal concentrations of factor VIII related antigen. These values and the diagnoses of severe hemophilia were confirmed with blood from the abortuses.     

The expression of Rho proteins decreases with human brain tumor progression: Potential tumor markers

Astrocytic tumors are the most common human brain tumors. Establishment of tumor grade is a key determinant both in the choice of a therapeutic approach and in the prognosis. The diagnosis of astrocytic tumors is currently determined following histopathological analysis. The identification of molecular markers would offer a complementary tool for characterizing tumors with respect to their clinical behavior. In this study we determined the expression levels of 3 small GTP binding proteins (RhoA, RhoB and Rac1), of their inhibitor RhoGDI and of caveolin-1 in 24 human astrocytic tumors of grades I to IV. Our results demonstrated that the expression of RhoA and RhoB decreased significantly in all brain tumors studied and was inversely related with tumor of grade II to IV malignancy. The amount of caveolin-1 immunodetected was not significantly different from normal brain samples while the Rac1 expression level was diminished in astrocytic tumors of grades III and IV. Our finding that RhoA and RhoB expression levels are correlated to tumor malignancy suggests that they may serve as novel and efficient diagnostic markers for astrocytic brain tumors of histological grade II to IV and complement currently applied histopathological analysis.     

Follow up study of cow's milk protein intolerant infants

Over a period of 4 years, 88 infants with cow's milk protein intolerance (CMPI) were followed prospectively in order to evaluate the persistence of CMPI and its relationship between either serum IgE levels or RAST results for cow's milk. After exclusion of lactose intolerance, two positive cow's milk elimination challenge tests were considered diagnostic for CMPI. At the age of 1, 2, 3 and 4 years respectively, 85%, 78%, 49% and 33% of the children still were cow's milk intolerant. Initial serum values of IgE 10 kU/l indicated a late development of tolerance to cow' milk proteins. At the age of 4 years, 90% of infants with initial IgE levels <10 k U/l had become tolerant to cow's milk while this was the case for only 47% of infants with initial IgE levels 10 k U/l. Initial RAST results for cow's milk bore no obvious relationship to outcome.     

Effects of a proton-pump inhibitor in cystic fibrosis

Most children with cystic fibrosis (CF) show persisting steatorrhoea even when treated with pancreatic enzyme. As a low duodenal pH could be responsible for this persisting fat loss, we evaluated the effects of a proton-pump inhibitor (lansoprazole) on both steatorrhoea and growth parameters in 15 CF patients, aged 3.1–22.6y. Acid steatocrit, anthropometry and dual-energy X-ray absorptiometry were used to evaluate steatorrhoea and the nutritional status before, during and 3 months after stopping lansoprazole treatment (15mg/d for 3 months). Mean ± SD acid steatocrit values decreased from 37.1 ± 8.8% to 28.5 ± 10.6% ( p = 0:02). Significant mean Z -score improvements were found for weight (+0:14; p = 0:02), height (+0:15; p = 0:03), subscapular (+0:61; p = 0:003), supra-iliac (+0:8; p = 0:002) and the sum of the four measured skinfolds (+0:61; p = 0:002). Z -scores deteriorated again after stopping lansoprazole. Fat mass and bone mineral content increased significantly on lansoprazole ( p = 0:008 and p = 0:005, respectively). We conclude that lansoprazole as adjuvant therapy significantly improves both steatorrhoea and the nutritional status in CF children who maintain steatorrhoea while on pancreatic enzymes.