Correlation between Epstein Barr virus antibodies, serum IgE and atopic disease

It is currently accepted that vinil infections may influence the development of atopy. In the present study we evaluated serum IgE levels as well as the prevalence of symptom-, indicative of utopic disease and EBV antibodies in 353 children aged from I month to 19 years. Antibodies against EBV were detected by immunofluorescence. IgE levels in serum were measured by en/. yme imimmoassay. Dividing ihe study population according to EBV seropositivity and age, we noted that the prevalence of high IgE levels (> 2 s. d.) was, in total, more frequent in the EBV negative (32. 9%) than in the positive subjects (27. 6%). Interestingly, this higher prevalence was found only in the groups aged under six, especially in the 7 to 29 month group, where it was statistically significant (p=0.037), whereas in the 6-19 year group the situation was reversed. Furthermore, selecting only the atopic children younger than 3 years of age with high IgE levels and clinical symptoms of atopy (wheezing and/or dermatitis) it was possible to demonstrate lower EBV seropositivity compared with the normal IgE controls for each group, even though these differences were not statistically significant. In conclusion, the results of our study suggest that, in our selected population, EBV infection in the first years of life is associated with a lower prevalence of high IgE levels.     

Wound healing activity of aqueous extract of Crotalaria verrucosa in Wistar albino rats

ObjectiveTo evaluate the wound healing effect of aqueous extract of Crotalaria verrucosa (C. verrucosa) in rats.MethodsThree wound models including incision, excision and dead space wounds were used in this study. The parameters studied were breaking strength in incision models, granulation tissue dry weight, breaking strength and hydroxyproline content in dead space wounds, percentage of wound contraction and period of epithelialization in excision wound model.ResultsTwo doses of the extract with and without dexamethasone showed significant increases in mean hydroxyproline, total protein content and dry weight of granulation tissue but it was higher with dose 800 mg/kg comparing with the control. The dexamethasone treated group showed a significant (P<0.001) reduction in the wound breaking strength when compared to control group in incision type of wound model. Coadministration of C. verrucosa with dexamethasone significantly (P<0.001) increased the breaking strength compared to the dexamethasone treated only group. In excision wound model, the percentage of the wound contraction was significantly (P<0.01) increased by two doses of test extract on all the days except the lower dose which exhibited only on 12 th, 16 th days of drug treatment and it also reversed the dexamethasone suppressed wound contraction. It significantly (P <0.001) reduced the time required for epithelialization and reversed the epithelialization delaying effect of dexamethasone (P<0.001).ConclusionsC. verrucosa was found to possess significant wound healing property. This was evident by decrease in the period of epithelialization, increase in the rate of wound contraction, skin breaking strength, and granulation tissue dry weight content. Hence C. verrucosa could be a good wound healing agent.     

Abnormal function of the bone marrow microenvironment in chronic myelogenous leukemia: role of malignant stromal macrophages

The bone marrow microenvironment supports and regulates the proliferation and differentiation of hematopoietic cells. Dysregulated hematopoiesis in chronic myelogenous leukemia (CML) is caused, at least in part, by abnormalities in CML hematopoietic progenitors leading to altered interactions with the marrow microenvironment. The role of the microenvironment itself in CML has not been well characterized. We examined the capacity of CML stroma to support the growth of long-term culture-initiating cells (LTC-IC) obtained from normal and CML marrow. The growth of normal LTC-IC on CML stroma was significantly reduced compared with normal stroma. This did not appear to be related to abnormal production of soluble factors by CML stroma because normal LTC- IC grew equally well in Transwells above CML stroma as in Transwells above normal stroma. In addition, CML and normal stromal supernatants contained similar quantities of both growth-stimulatory (granulocyte colony-stimulating factor (CSF), interleukin-6, stem cell factor, granulocyte-macrophage CSF, and interleukin-1 beta) and growth- inhibitory cytokines (transforming growth factor-beta, macrophage inflammatory protein-1 alpha, and tumor necrosis factor-alpha). The relative proportion of different cell types in CML and normal stroma was similar. However, polymerase chain reaction and fluorescence in situ hybridization studies showed the presence of bcr-abl-positivo cells in CML stroma, which were CD14+ stromal macrophages. To assess the effect of these malignant macrophages on stromal function, CML and normal stromal cells were separated by fluorescence-activated cell sorting into stromal mesenchymal cell (CD14-) and macrophage (CD14+) populations. CML and normal CD14- cells supported the growth of normal LTC-IC equally well. However, the addition of CML macrophages to normal or CML CD14- mesenchymal cells resulted in impaired progenitor support. This finding indicates that the abnormal function of CML bone marrow stroma is related to the presence of malignant macrophages. In contrast to normal LTC-IC, the growth of CML LTC-IC on allogeneic CML stromal layers was not impaired and was significantly better than that of normal LTC-IC cocultured with the same CML stromal layers. These studies demonstrate that, in addition to abnormalities in CML progenitors themselves, abnormalities in the CML marrow microenvironment related to the presence of malignant stromal macrophages may contribute to the selective expansion of leukemic progenitors and suppression of normal hematopoiesis in CML.     

Kinetic evaluation of the pool sizes and proliferative response of neutrophils in bacterially challenged aging mice

Clinical observations during infection suggest that in aged patients, the kinetic or proliferative responses of neutrophils to infection may be deranged. To test this hypothesis, the neutrophil responses of 6- month-old and 30-month-old mice were compared. After intrapulmonary injection of Escherichia coli, young mice exhibited neutrophilia and diminution of the neutrophil storage pool (NSP) by a mean of 6.4 x 10(6) neutrophils/two femurs. This was accompanied by an increase in the pool of CFU-GM from a control value of 1.1 x 10(5) cells/two femurs (range 0.7 to 1.4) to 1.5 x 10(5) (1.1 to 1.9) (P less than .05) and the thymidine suicide (relative proliferative rate) of CFU-GM rose from 27% (19 to 42) to 51% (31 to 61) (P less than .05). Furthermore, the CFU-GM of infected young mice displayed enhanced differentiation to the neutrophil series. In contrast, old mice exhibited a greater mean diminution of the NSP: 12.8 x 10(6) neutrophils. Also, old mice experienced a reduction in CFU-GM from 2.3 x 10(5) (1.0 to 3.9) (controls) to 1.3 x 10(5) (1.2 to 1.5)/two femurs (P less than .05), a reduction in the proliferation of CFU-GM and reduced differentiation of CFU-GM to neutrophils. These experiments establish that the neutrophil response of infected old mice is disordered, with exaggerated depletion of the NSP and lack of stimulus-driven granulocytopoiesis as reflected by a paradoxical reduction in the number and proliferative rate of precursors. This defect may be compounded by decreased differentiation of precursors to neutrophils.     

A diaphragmatic retroperitoneal cyst

Diaphragmatic lesions are usually congenital bronchogenic cysts. A patient with a known diaphragmatic cyst presented with new onset right upper quadrant pain. Repeat imaging showed enlargement of the cyst, the CA19–9 cancer marker was raised at 312iu/ml (normal: <27iu/ml) and positron emission tomography combined with computed tomography showed focally increased uptake in the cystic wall. In view of symptoms and risk of neoplasia, the lesion was excised. Histology showed a benign epidermoid cyst. Features falsely suggesting neoplasia have been reported previously with benign splenic cysts but not with a benign diaphragmatic epidermoid cyst.     

Depletion of recipient CD4+ but not CD8+ T lymphocytes prevents the development of cardiac allograft vasculopathy

BACKGROUND: We have described that chimeric rat hearts bearing recipient-type antigen-presenting cells (APCs) do not reject acutely, but develop cardiac allograft vasculopathy (CAV) in untreated recipients. This suggests that CAV is triggered either by CD8+ direct allorecognition or by CD4+ indirect allorecognition. To determine the allorecognition pathway responsible for CAV in this model, recipients of chimeric hearts underwent either CD8+ or CD4+ T cell depletion. METHODS: Chimeric hearts were created via bone marrow transplantation in two fully major histocompatibility-mismatched rat strain combinations. DA recipients were thymectomized and treated with Ox8 and Ox38 murine monoclonal antibodies, which deplete CD8+ and CD4+ T cells, respectively. Chimeric PVG hearts bearing DA APCs, abbreviated PVG(DA), were heterotopically transplanted into recipients undergoing thymectomy alone or recipients undergoing thymectomy plus either CD4+ or CD8+ T cell depletion. RESULTS: PVG(DA) allografts survived 100 days, but developed CAV in thymectomized recipients and in those permanently depleted of CD8+ T cells. In contrast, chimeric hearts transplanted into permanently CD4+ T cell-depleted recipients survived 100 days and demonstrated no evidence of CAV. CONCLUSIONS: In this specific strain combination, recipient CD8+ T cells are neither necessary nor sufficient for the development of CAV, whereas recipient CD4+ T cells are required for the development of CAV. These findings suggest that CAV is dependent on CD4+ indirect allorecognition and that CD8+ direct allorecognition stimulated by nonprofessional APCs plays a minor role.