Flavonoid Rutin Alters the Viability and Function of Mitogen-Stimulated Splenocytes and Thymocytes Compared with Non Stimulated Cells

Rutin is a flavonoid obtained from Dimorphandra mollis (Benth.), a medicinal Brazilian plant used as antioxidative, antihemorrhagic, and blood vessel protector. The present study has examined its effects on the viability and function of immune system cells in vitro. Rat spleen and thymus cells were cultured with 10 nM, 1 microM, and 10 microM of the drug in the presence or absence of PWM, LPS, or ConA mitogens. Cellular proliferation was analyzed by H(3)-thymidin uptake and IFN-gamma and IL-10 were measured by ELISA after 48 and 72 hr. Viability was measured by flow cytometry using Annexin V and PI after 24 and 48 hr. The flavonoid rutin inhibited splenocytes and thymocytes proliferation under ConA stimulation observed by an increase on apoptosis levels of thymocytes stimulated with PWM in 24 hr and on splenocytes stimulated with PWM in 48 hr. Function studies showed a decrease on IFN-gamma production by splenocytes and thymocytes stimulated with PWM or ConA. Spleen cells cultured with LPS and rutin showed a decrease on apoptosis after 24 hr and an increase on the IL-10 levels after 48 hr. There was no significant variation on the necrosis rate, viability, and function of cells treated with rutin in the absence of mitogenic stimulus.

Different effects of arborinine alkaloid obtained from Brazilian Erthela baihensis on spleen and thymus cells stimulated in vitro with different mitogens

The present study has examined the effects of arborinine, an alkaloid obtained from Erthela bahiensis, a Brazilian plant popularly used as diuretic, antidiabetic, antithermic and expectorant, on the viability and function of immune system cells in vitro using a murine model. Rat spleen and thymus cells were cultured with 10 nM, 1 microM, 10 microM of the drug in the presence or absence of pokeweed (PWM), lipopolysaccharide (LPS), or concanavallin (ConA) mitogens. Cellular proliferation was analyzed by H3-thymidin uptake after 48 and 72 hr. Our results showed an inhibitory effect of arborinine on splenocytes proliferation under ConA or PWM stimulation and increased apoptosis on splenocytes and thymocytes stimulated with PWM in 24 hr. A decrease was observed on Interferon gamma (IFN-gamma) production by ConA- or LPS-stimulated splenocytes in 48 hr and 72 hr and ConA- or PWM-stimulated thymocytes in 72 hr. In contrast, an increase on lymphoproliferation was observed on LPS-stimulated splenocytes and ConA- or PWM-stimulated thymocytes in 48 hr. On this period, apoptosis decreased on LPS- or PWM-stimulated splenocytes and IFN-gamma production increased in PWM stimulated thymocytes. Arborinine also induced a decrease on Interleukin-10 production by splenocytes and thymocytes stimulated with ConA or PWM. There was no significant variation on the necrosis rate of the cells treated with arborinine or any change on their viability or function values in the absence of mitogenic stimulus.

In vitro IFN-gamma production by goat blood cells after stimulation with somatic and secreted Corynebacterium pseudotuberculosis antigens

Corynebacterium pseudotuberculosis is the causal agent of caseous lymphadenitis, a chronic illness that attacks goats and sheep characterized by pyogranulomas formation in lymph nodes and organs. Regarding the current knowledge of the pathogenesis of the caseous lymphadenitis, there is evidence that besides the humoral response the induction of a durable cellular response is fundamental for its control. In this sense, research on antigens of C. pseudotuberculosis that are capable to inducing cellular immunity is an important step for the development of diagnosis tests and more efficient vaccines. In the present study, the interferon-gamma production in cultures of whole blood from infected goats stimulated with secreted bacterial antigen or somatic antigen were used to evaluate the cellular response. The results demonstrated a significant difference in the ability of the two antigens to induce a cellular response. That is, IFN-gamma production was high with cells from infected animals in response to the secreted antigen while IFN-gamma production was low when somatic antigen was used. The concomitant use of these antigens with PWM also showed differences. That is, the secreted antigen increased the IFN-gamma production induced by PWM, while the somatic antigen seems not to have altered the response to PWM.

Vascular endothelial growth factor (VEGF) levels as a tool to discriminate between malignant and nonmalignant ascites

Ascites formation is commonly associated with cancer, although it is also present in other diseases. The aim of this study was to evaluate the usefulness of vascular endothelial growth factor as a malignancy marker in ascites of different etiologies. The levels of VEGF in 32 malignant and in 31 non-malignant ascites were determined by enzyme immunoassay (ELISA). VEGF levels were significantly higher in malignant than in non-malignant ascites (median=1265.9 pg/ml x 114.6 pg/ml; p<0.0001). We observed 72% sensitivity and 90% specificity, using 662 pg/ml as a cut-off value. Therefore, this approach can be used as a marker for a first screening to discriminate between malignant and nonmalignant ascites.

Three-phase partitioning as an efficient method for extraction/concentration of immunoreactive excreted–secreted proteins of Corynebacterium pseudotuberculosis

The three-phase partitioning (TPP) technique was used upstream to isolate/concentrate secreted proteins from Corynebacterium pseudotuberculosis cultured in a complex liquid medium. Several parameters of the TPP technique (15, 30, or 60% ammonium sulfate concentration; 4.0, 5.5, or 7.0 pH; and primary (n) or tertiary (t)-butanol solvent isomer) were varied to determine the optimal recovery of serologically and cellularly immunoreactive extracted proteins. A TPP extraction made with 30% ammonium sulfate and an initial pH of 4.0 gave the best humoral and cellular immunoreactivity of caseous lymphadenitis infected goats. In particular, two immunogenic secreted (16 and 125 kDa) proteins, which had not been found by other extraction methods, were identified.

Experimental Corynebacterium pseudotuberculosis primary infection in goats: kinetics of IgG and interferon-gamma production, IgG avidity and antigen recognition by Western blotting

Corynebacterium pseudotuberculosis is the cause of caseous lymphadenitis (CLA) in small ruminants, a chronic granulomatous disease that provokes significant zootechnics losses to ovine and goat breeders in northern Brazil. The present work was conducted to analyse aspects of humoral and cellular immune responses after experimental infection. Eight goats were infected intradermally with a single dose of virulent C. pseudotuberculosis strain and specific IgG, interferon-gamma (IFN-gamma) production as well as IgG avidity and antigens pattern recognition dynamics against an excreted-secreted antigen were recorded during 20 weeks. At the end of the follow-up, animals were slaughtered and necropsied. Although no animals showed apparent clinical signs of infection at the end of the trial, IFN-gamma response, even more so than the humoral response, differentiated animals into two groups of high or medium/low response. The time-course of IFN-gamma production presented a short-lived primary response on day 5 after infection of animals of both groups, and a strong and long lasting secondary response starting on day 16 after infection in the high response group. The indirect ELISA used was able to detect a positive antibody titre between 6 and 11 days after infection in the two groups. IgG avidity index oscillated initially between 15 and 45%, and showed approximately 5% units increment during the 20 follow-up weeks. With only one individual exception, the qualitative antigens pattern recognition showed on day 11 after infection remained constant through the experiment. IgG avidity is highly correlated with IgG production, but could not be related with specific immunodominant bands. Both humoral and cellular responses kinetics presented a similar pattern of activation/deactivation but necropsy results suggested that the IFN-gamma test would be a very specific marker of CLA status.

Pancreatic tumors: evaluation with endoscopic US, CT, and MR imaging

PURPOSE

To compare the value of endosonography (endoscopic ultrasound [US]), dynamic computed tomography (CT), and magnetic resonance (MR) imaging in the evaluation of pancreatic tumors.

MATERIALS AND METHODS

Forty-nine consecutive patients with clinical suspicion of pancreatic tumor underwent endoscopic US (n = 49), CT (n = 46), and MR imaging (n = 25). The final diagnosis of a malignant (n = 22), benign (n = 2), or inflammatory (n = 9) tumor, or no (n = 16) tumor was made at surgery (n = 28) and/or a combination of biopsy (n = 9) and 9-24-month follow-up (n = 12).

RESULTS

The sensitivity was 94% for endoscopic US, 69% for CT, and 83% for MR imaging. Specificity was 100% for endoscopic US, 64% for CT, and 100% for MR imaging. Accuracy was 96% for endoscopic US, 67% for CT, and 84% for MR imaging. The sensitivity for the detection of tumors less than 3 cm in diameter was 93% for endoscopic US (n = 15), 53% for CT (n = 15), and 67% for MR imaging (n = 12).

CONCLUSION

Endoscopic US is more accurate than dynamic CT and MR imaging in the diagnosis of pancreatic tumor, particularly for tumors less than 3 cm in diameter.