Biomedical subjects

M Reitz

Publications and source records attributed to M Reitz.

At least 19 recordsLinked to original sources

PubMed2006

Interleukin-2/interferon-alpha2a/13-retinoic acid-based chemoimmunotherapy in advanced renal cell carcinoma: results of a prospectively randomised trial of the German Cooperative Renal Carcinoma Chemoimmunotherapy Group (DGCIN).

We performed a prospectively randomised clinical trial to compare the efficacy of four subcutaneous interleukin-2-(sc-IL-2) and sc interferon-alpha2a (sc-IFN-alpha2a)-based outpatient regimens in 379 patients with progressive metastatic renal cell carcinoma. Patients with lung metastases, an erythrocyte sedimentation rate < or =70 mm h(-1) and neutrophil counts < or =6000 microl(-1) (group I) were randomised to arm A: sc-IL-2, sc-IFN-alpha2a, peroral 13-cis-retinoic acid (po-13cRA) (n=78), or arm B: arm A plus inhaled-IL-2 (n=65). All others (group II) were randomised to arm C: arm A plus intravenous 5-fluorouracil (iv-5-FU) (n=116), or arm D: arm A plus po-Capecitabine (n=120). Median overall survival (OS) was 22 months (arm A; 3-year OS: 29.7%) and 18 months (arm B; 3-year OS: 29.2%) in group I, and 18 months (arm C; 3-year OS: 25.7%) and 16 months (arm D; 3-year OS: 32.6%) in group II. There were no statistically significant differences in OS, progression-free survival, and objective response between arms A and B, and between arms C and D, respectively. Given the known therapeutic efficacy of sc-IL-2/sc-INF-alpha2a/po-13cRA-based outpatient chemoimmunotherapies, our results did not establish survival advantages in favour of po-Capecitabine vs iv-5-FU, and in favour of short-term inhaled-IL-2 in patients with advanced renal cell carcinoma receiving systemic cytokines.

Adult↗

PubMed2006

An approach to estimating prognosis using fractional polynomials in metastatic renal carcinoma.

We present a prognostic model for metastatic renal cell carcinoma based on fractional polynomials. We retrospectively analysed 425 metastatic renal cell carcinoma patients treated with subcutaneous recombinant cytokine-based home therapies in consecutive trials. In our approach, we categorised a continuous prognostic index produced by the multivariable fractional polynomial (MFP) algorithm, using a strategy in which continuous predictors are kept continuous. The MFP algorithm selected five prognostic factors as significant at the 5% level in a multivariable model: lymph node metastases, liver metastases, bone metastases, age, C-reactive protein and neutrophils. The MFP model allowed us to divide patients into four risk groups achieving median overall survivals of 38 months (low risk), 23 months (low intermediate risk), 15 months (high intermediate risk) and 5.6 months (high risk). Our approach, based on categorising a continuous prognostic index produced by the MFP algorithm, allowed more flexibility in the determination of risk groups than traditional approaches.

Algorithms↗

PubMed2005

Adjuvant treatment with interleukin-2- and interferon-alpha2a-based chemoimmunotherapy in renal cell carcinoma post tumour nephrectomy: results of a prospectively randomised trial of the German Cooperative Renal Carcinoma Chemoimmunotherapy Group (DGCIN).

We conducted a prospectively randomised clinical trial to investigate the role of adjuvant outpatient immunochemotherapy administered postoperatively in high-risk patients with renal cell carcinoma. In total, 203 renal carcinoma patients' status post radical tumour nephrectomy were stratified into three risk groups: patients with tumour extending into renal vein/vena cava or invading beyond Gerota's fascia (pT3b/c pN0 or pT4pN0), patients with locoregional lymph node infiltration (pN+), and patients after complete resection of tumour relapse or solitary metastasis (R0). Patients were randomised to undergo either (A) 8 weeks of outpatient subcutaneous interleukin-2 (sc-rIL-2), subcutaneous interferon-alpha2a (sc-rIFN-alpha2a), and intravenous 5-fluorouracil (iv-5-FU) according to the standard Atzpodien regimen (Atzpodien et al, 2004) or (B) observation. Two-, 5-, and 8-year survival rates were 81, 58, and 58% in the treatment arm, and 91, 76, and 66% in the observation arm (log rank P=0.0278), with a median follow-up of 4.3 years. Two, 5-, and 8-year relapse-free survival rates were calculated at 54, 42, and 39% in the treatment arm, and at 62, 49, and 49% in the observation arm (log rank P=0.2398). Stage-adapted subanalyses revealed no survival advantages of treatment over observation, as well. Our results established that there was no relapse-free survival benefit and the overall survival was inferior with an adjuvant 8-week-outpatient sc-rIL-2/sc-rIFN-alpha2a/iv-5-FU-based immunochemotherapy compared to observation in high-risk renal cell carcinoma patients following radical tumour nephrectomy.

Adult↗

PubMed2005

Age does not impair the efficacy of immunochemotherapy in patients with metastatic renal carcinoma.

PURPOSE: Based on the increasing proportion of elderly cancer patients, we compared the efficacy of subcutaneous cytokine based home therapy in older (age > or = 60 years) and younger (age < 60 years) patients with metastatic renal cell carcinoma. PATIENTS AND METHODS: As a rule, patients at an age of 60 years or older received a 20% dose reduction of s.c. IL-2. Treatment consisted of (A) s.c. interferon-alpha2a (s.c. INF-alpha2a), s.c. interleukin-2 (s.c. IL-2), (B) s.c. IFN-alpha2a, s.c. IL-2 and i.v. 5-fluorouracil (5-FU) or (C) s.c. IFN-alpha2a, s.c. IL-2 and i.v. 5-FU combined with p.o. 13-cis-retinoic acid (p.o. 13cRA). RESULTS: Patient age groups > or = 60 years (n=174) and < 60 years (n=251) showed no significant difference in objective response (27% versus 31%), in median overall survival (22 months versus 19 months), and in progression-free survival (6 months versus 5 months). Within the elderly patients group, median overall survival was 20 months (pts. 60-64 years) versus 23 months (pts. > or = 65 years) and median progression-free survival was 4 months (pts. 60-64 years) versus 8 months (pts. > or = 65 years). CONCLUSION: Our results demonstrated that patient age and related IL-2 dose reduction do not impair the efficacy of s.c.-IL-2 plus s.c.-INF-2a based outpatient immunochemotherapy in metastatic renal carcinoma.

Age Factors↗

PubMed2004

Interleukin-2- and interferon alfa-2a-based immunochemotherapy in advanced renal cell carcinoma: a Prospectively Randomized Trial of the German Cooperative Renal Carcinoma Chemoimmunotherapy Group (DGCIN).

PURPOSE: We conducted a prospectively randomized clinical trial to compare the efficacy of three outpatient therapy regimens in 341 patients with progressive metastatic renal cell carcinoma. PATIENTS AND METHODS: Patients were stratified according to known clinical predictors and were subsequently randomly assigned. Treatment arms were: arm A (n = 132), subcutaneous interferon alfa-2a (sc-IFN-alpha-2a), subcutaneous interleukin-2 (sc-IL-2), and intravenous (IV) fluorouracil; arm B (n = 146): arm A treatment combined with per oral 13-cis-retinoic acid; and arm C (n = 63), sc-IFN-alpha-2a and IV vinblastine. RESULTS: Treatment (according to the standard 8-week Hannover Atzpodien regimen) arms A, B, and C yielded objective response rates of 31%, 26%, and 20%, respectively. Arm B, but not arm A, showed a significantly improved progression-free survival (PFS) compared with arm C (P =.0248). Both arm A (median overall survival, 25 months; P =.0440) and arm B (median overall survival, 27 months; P =.0227) led to significantly improved overall survival (OS) compared with arm C (median OS, 16 months). All three sc-IFN-alpha-2a-based therapies were moderately or well tolerated. CONCLUSION: Our results established the safety and improved long-term therapeutic efficacy of sc-IL-2 plus sc-INF-alpha-2a-based outpatient immunochemotherapies, compared with sc-INF-alpha-2a/IV vinblastine.

Adult↗

PubMed2004

The collaborative practice of dental hygiene.

This paper discusses the collaborative practice of dental hygiene, primarily using examples from California and New Mexico. Several advantages are discussed, including an increased access to all populations and more respect for the field. The earliest roles of a dental hygienist reflect common components of a collaborative practice. Responsibilities of dental hygienists today as educators and preventive dental providers are also tied to this type of practice. Currently, few states in the USA allow such practices; however, benefits are discussed and the positive effects noted. Opposition to these practices exists, although the concerns have not been proven accurate. Collaborative dental hygiene practices are shown to be a positive avenue through which the population can gain access to noted provider shortages, as well as a rewarding option for the field of dental hygiene.

California↗

PubMed2003

Rapid deterioration in quality of life during interleukin-2- and alpha-interferon-based home therapy of renal cell carcinoma is associated with a good outcome.

We conducted a prospective quality-of-life analysis during outpatient immunotherapy in 22 patients with progressive metastatic renal cell carcinoma (RCC) treated with subcutaneous interferon-alpha2a and subcutaneous interleukin-2. Patients' quality of life was assessed by the European Organization for Research and Treatment of Cancer quality-of-life questionnaire QLQ-C30 before (week 0) and once during immunotherapy (week 3). Advanced renal cancer patients completed a total of 30 questionnaires before therapy (week 0) and after 3 weeks of therapy. Their mean quality of life (global-quality-of-health status) deteriorated significantly, from 64 to 41 (P</=0.001) during the first 3 weeks after treatment initiation, due to a mean reduction in physical (from 82 to 65; P</=0.001), emotional (from 77 to 61; P</=0.01), social (from 78 to 55; P</=0.01), and role functioning (from 82 to 58; P</=0.01). In contrast, cognitive functioning did not differ significantly from pretreatment scores after 3 weeks of therapy. In addition, during the first 3 weeks, appetite loss (from 18 to 59; P</=0.01), fatigue (from 33 to 56; P</=0.01), nausea/vomiting (from 10 to 26; P</=0.01), sleep disturbance (from 27 to 47; P</=0.01), diarrhoea (from five to 27; P</=0.01), and pain (from 20 to 32; P</=0.05) were significantly increased, while quality-of-life symptoms such as dyspnoea, and constipation were not significantly influenced by therapy. Complete response to RCC outpatient immunotherapy was associated with the most predominant reduction in functional quality of life when compared against patients in progressive or stable disease or partial tumour response. In conclusion, quality-of-life analysis during outpatient immunotherapy yielded modest changes in patients' health status 3 weeks after therapy initiation. Since the rapid decline in functional quality-of-life was associated with therapeutic efficacy, it is suggested that quality-of-life analysis might serve as an early indicator for immunotherapy response in metastatic RCC. British Journal of Cancer (2003) 89, 50-54. doi:10.1038/sj.bjc.6600996 www.bjcancer.com

Aged↗

PubMed2003

Metastatic renal carcinoma comprehensive prognostic system.

The purpose of the study was to identify a comprehensive prognostic system of pretreatment clinical parameters in 425 patients (pts) with metastatic renal-cell carcinoma treated with different subcutaneous (s.c.) recombinant cytokine-based home therapies in consecutive trials. Treatment consisted of (A) s.c. interferon-alpha 2a (INF-alpha), s.c. interleukin-2 (IL-2) (n=102 pts), (B) s.c. IFN-alpha 2a, s.c. IL-2, and i.v. 5-fluorouracil (5-FU) (n=235 pts) or (C) s.c. IFN-alpha 2a, s.c. IL-2, and i.v. 5-FU combined with p.o. 13-cis-retinoic acid (13cRA) (n=88 pts). Kaplan-Meier survival analysis, log-rank statistics, and Cox regression analysis were employed to identify risk factors and to create a multiple risk factor model. The following pretreatment risk factors were identified by univariate analysis: (1) three and more metastatic sites, (2) presence of liver, lymph node or bone metastases, (3) neutrophil count > or = 6500 cells microl(-1), (4) serum lactate dehydrogenase level (LDH) > or = 220 U l(-1), and (5) serum C-reactive protein level (CRP) > or = 11 mg l(-1). Cox regression analysis with forward stepwise variable selection identified neutrophil count as the major prognostic factor (hazard ratio=1.9, P<0.001), while serum levels of LDH and CRP, time between diagnosis of tumour and onset of metastatic disease, number of metastatic sites, and bone metastases were significant but somewhat less important prognostic variables within the multiple risk factor model (hazard ratio < or = 1.5). Patients were assigned to one of the three risk groups according to cumulative risk defined as the sum of simplified risk s.c.ores for six pretreatment variables. Low-, intermediate-, and high-risk patients achieved a median overall survival of 32+ months (95% CI 24, 43; 5-year survival of 27%), 18+ months (95% CI 15, 20; 5-year survival of 11%), and 8+ months (95% CI 6, 10; 5-year survival of 5%), respectively. These prognostic categories are helpful both in individual patient care and in the assessment of patients entering prospective clinical trials.

Carcinoma, Renal Cell↗

PubMed2002

Molecular surveillance of HIV-1 field strains in Nigeria in preparation for vaccine trials.

We conducted a national molecular epidemiologic survey of HIV-1 strains in Nigeria to determine the most prevalent subtype(s) for use in developing candidate vaccines. A total of 230 HIV-1-positive blood samples collected from 34 of the 36 Nigerian states were analyzed by our modified env gp41-based heteroduplex mobility assay (HMA) and/or gp41 sequencing and analysis. Overall, 103 (44.8%) were subtype A, 125 (54.3%) were subtype G, one (0.4%) was subtype C, and one (0.4%) was subtype J, and one (0.4%) was unclassifiable. To further characterize Nigerian viruses to aid in strain selection for candidate vaccines, one gp41 subtype G and five gp41 subtype A strains were selected for full envelope sequencing. The one subtype G sequence had consistent phylogenies throughout gp160, using programs to detect recombination. However, all five sequences that were primarily subtype A in gp41 were found to be recombinant viruses. Two of the five (40%) were A/G/J mosaics with common breakpoints. The remaining three gp160 recombinants all had their own unique break points: two A/? and one A/?/G, however, all five had the majority of their mosaic breakpoints occurring in gp41. None of the five were consistent with the circulating recombinant form (CRF)02_AG strain previously reported to be prevalent in West Africa. In conclusion, we showed a clear dominance and widespread distribution of gp41 subtypes A and G in fairly equal proportions, suggesting that vaccines designed for use in this geographic locale should incorporate the gene(s) of both subtypes. However, appreciating the magnitude of diversity of HIV-1 strains in Nigeria may require sequencing and analysis of longer gene regions for the identification of prevalent or emerging CRFs.

AIDS Vaccines↗

PubMed2002

Combination chemotherapy with or without s.c. IL-2 and IFN-alpha: results of a prospectively randomized trial of the Cooperative Advanced Malignant Melanoma Chemoimmunotherapy Group (ACIMM).

The purpose of this randomized trial was to evaluate the efficacy of combination chemoimmunotherapy compared with chemotherapy alone. A total of 124 patients were randomized to receive intravenous cisplatin (35 mg m(-2), days 1-3), carmustine (150 mg m(-2), day 1, cycles 1 and 3 only), dacarbacine (220 mg m(-2), days 1-3) and oral tamoxifen (20 mg m(-2), daily) in combination with (n=64) or without (n=60) sequential subcutaneous IL-2 and IFN-alpha. In those patients who received sequential immunotherapy, each cycle of chemotherapy was followed by outpatient s.c. IL-2 (10 x 10(6) IU m(-2), days 3-5, week 4; 5 x 10(6) IU m(-2), days 1, 3, 5, week 5) and s.c. IFN-alpha (5 x 10(6) IU m(-2), day 1, week 4; days 1, 3, 5, week 5). The overall response rate of patients treated with the combination of chemotherapy and IL-2/IFN-alpha was 34.3% with seven complete responses (10.9%) and 15 partial responses (23.4%). In patients treated with chemotherapy, only, the overall response rate was 29.9% with eight complete responses (13.3%) and 10 partial responses (16.6%). There was no significant difference in median progression free survival (0 months vs 4 months) and in median overall survival (12 months vs 13 months) for combined chemoimmunotherapy and for chemotherapy, respectively.

Administration, Oral↗

PubMed2002

[Aortico-left ventricular tunnel: a rare differential diagnosis of congenital aortic insufficiency].

Aortico-left ventricular tunnel (ALVT) is a rare congenital cardiac malformation that presents with cardiac failure and clinical findings of severe aortic regurgitation in early infancy. The diagnosis should be made with 2-D echocardiography by demonstrating an abnormal tunnel-like structure that connects the ascending aorta with the left ventricle. Up to 45% of the patients may have associated cardiac defects, and the development of this bizarre lesion is still unclear. In contrast to congenital aortic regurgitation, ALVT has a better prognosis. Early surgical intervention is curative, but non-operated children die because of heart failure. Therefore, knowledge of this rare cardiac malformation is mandatory if an infant presents with findings of aortic regurgitation.

Aorta↗

PubMed2002

Interleukin-12 inhibits apoptosis in chronic lymphatic leukemia (CLL) B cells.

The purpose of the present study was to investigate the effect of interleukin-12 on apoptosis of chronic lymphatic leukemia (CLL) B cells. Apoptotic indices were determined in highly purified CD5(+) B lymphocytes isolated from peripheral blood of seven patients with histologically confirmed CLL. Interleukin-4 as a known inhibitor of apoptosis was used as control. Quantitative analysis of apoptosis was determined by cell death detection ELISA. Our findings indicate that interleukin-12 inhibits ex vivo apoptosis in a large proportion of B-CLL patients and may be closely involved in the pathogenesis of disease. Therefore, our results may help identify potential new therapeutic targets in this malignancy.

Adult↗

PubMed2001

IL-2 in combination with IFN- alpha and 5-FU versus tamoxifen in metastatic renal cell carcinoma: long-term results of a controlled randomized clinical trial.

We conducted a prospectively randomized clinical trial to compare the efficacy and safety of subcutaneous interferon-alpha2a, subcutaneous interleukin-2 and intravenous 5-fluorouracil as home therapy against oral tamoxifen in 78 patients with progressive metastatic renal cell carcinoma. Treatment courses consisted of interferon-alpha2a 5 x 10(6) IU m(-2), day 1 weeks 1 + 4; days 1, 3, 5 weeks 2 + 3; 10 x 10(6) IU m(-2), days 1, 3, 5 weeks 5-8; interleukin-2 10 x 10(6) IU m(-2), twice daily days 3-5 weeks 1 + 4; 5 x 10(6) IU m(-2), days 1, 3, 5 weeks 2 + 3; and 5-fluorouracil 1000 mg m(-2), day 1 weeks 5-8. The tamoxifen group received tamoxifen 80 mg twice daily over 8 weeks. Among 41 patients treated with interleukin-2, interferon-alpha2a and 5-fluorouracil there were 7 complete (17.1%) and 9 partial responders (21.9%), with an overall objective response rate of 39.1% (95% CI, 24.2-55.5). An additional 15 patients (36.6%) were stable throughout therapy. The overall survival was 24 months (range 5-76+). In 37 patients receiving tamoxifen no objective remissions occurred. 13 patients (35.1%) had stable disease and 24 patients (64.9%) showed continued disease progression. The overall survival was 13 months (range 3-73+). In summary, this home-based therapy regimen of interferon-alpha2a, interleukin-2 and 5-fluorouracil demonstrated significant therapeutic efficacy in patients with progressive renal cell carcinoma when compared to hormonal therapy.

Adult↗

PubMed2001

An HIV-1 transgenic rat that develops HIV-related pathology and immunologic dysfunction.

We report, to our knowledge, the first HIV type 1 (HIV-1) transgenic (Tg) rat. Expression of the transgene, consisting of an HIV-1 provirus with a functional deletion of gag and pol, is regulated by the viral long terminal repeat. Spliced and unspliced viral transcripts were expressed in lymph nodes, thymus, liver, kidney, and spleen, suggesting that Tat and Rev are functional. Viral proteins were identified in spleen tissue sections by immunohistochemistry and gp120 was present in splenic macrophages, T and B cells, and in serum. Clinical signs included wasting, mild to severe skin lesions, opaque cataracts, neurological signs, and respiratory difficulty. Histopathology included a selective loss of splenocytes within the periarterial lymphoid sheath, increased apoptosis of endothelial cells and splenocytes, follicular hyperplasia of the spleen, lymphocyte depletion of mesenteric lymph nodes, interstitial pneumonia, psoriatic skin lesions, and neurological, cardiac, and renal pathologies. Immunologically, delayed-type hypersensitivity response to keyhole limpet hemocyanin was diminished. By contrast, Ab titers and proliferative response to recall antigen (keyhole limpet hemocyanin) were normal. The HIV-1 Tg rat thus has many similarities to humans infected with HIV-1 in expression of viral genes, immune-response alterations, and pathologies resulting from infection. The HIV-1 Tg rat may provide a valuable model for some of the pathogenic manifestations of chronic HIV-1 diseases and could be useful in testing therapeutic regimens targeted to stages of viral replication subsequent to proviral integration.

Animals↗

PubMed2001

Development of an env gp41-based heteroduplex mobility assay for rapid human immunodeficiency virus type 1 subtyping.

The gp120 region of the human immunodeficiency virus type 1 (HIV-1) envelope (env) gene exhibits a high level of genetic heterogeneity across the group M subtypes. The heteroduplex mobility assay (HMA) has successfully been used to assign subtype classifications, but C2V5 primers often fail to amplify African strains. We developed an env gp41-based HMA for which the target sequence is amplified with highly conserved gp41 primers, known to efficiently amplify nucleic acids from HIV-1 group M, N, and O viruses. By using gp41 from a new panel of reference strains, the subtype assignments made by our modified HMA were concordant with those obtained by sequencing and phylogenetic analysis of 34 field strains from 10 countries representing subtypes A to G. Testing of field strains from Nigeria further demonstrated the utility of this modified assay. Of 28 samples, all could be amplified with gp41 primers but only 17 (60.7%) could be amplified with the standard C2V5 primers. Therefore, gp41-based HMA can be a useful tool for the rapid monitoring of prevalent subtypes in countries with divergent strains of circulating HIV-1.

DNA, Viral↗

PubMed2001

Human immunodeficiency virus type 1 IIIB selected for replication in vivo exhibits increased envelope glycoproteins in virions without alteration in coreceptor usage: separation of in vivo replication from macrophage tropism.

Analysis of viral replication and pathogenicity after in vivo selection of human immunodeficiency virus type 1 (HIV-1) attenuated in vitro will help to define the functions involved in replication and pathogenesis in vivo. Using the SCID-hu Thy/Liv mouse and human fetal thymus organ culture as in vivo models, we previously defined HIV-1 env determinants (HXB2/LW) which were reverted for replication in vivo (L. Su et al., Virology 227:46-52, 1997). In this study, we examined the replication of four highly related HIV-1 clones directly derived from Lai/IIIB or after selection in vivo to investigate the envelope gp120 determinants associated with replication in macrophages and in the thymus models in vivo. The LW/C clone derived from the IIIB-infected laboratory worker and HXB2/LW both efficiently infected monocyte-derived macrophages (MDM) and the human thymus. Although the laboratory worker (LW) isolates showed altered tropism from IIIB, they still predominantly used CXCR4 as coreceptors for infecting peripheral blood mononuclear cells, macrophages, and the thymus. Interestingly, a single amino acid mutation in the V3 loop associated with resistance to neutralizing antibodies was also essential for the replication activity of the LW virus in the thymus models but not for its activity in infecting MDM. The LW virions were equally sensitive to a CXCR4 antagonist. We further demonstrated that the LW HIV-1 isolate selected in vivo produced more infectious viral particles that contained higher levels of the Env protein gp120. Thus, selection of the laboratory-attenuated Lai/IIIB isolate in vivo leads to altered tropism but not coreceptor usage of the virus. The acquired replication activity in vivo is correlated with an early A-to-T mutation in the V3 loop and increased virion association of HIV-1 Env gp120, but it is genetically separable from the acquired replication activity in macrophages.

Animals↗

PubMed2001

Activation of NF-kappaB by the human herpesvirus 8 chemokine receptor ORF74: evidence for a paracrine model of Kaposi's sarcoma pathogenesis.

Infection with human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma (KS)-associated herpesvirus, is necessary for the development of KS. The HHV-8 lytic-phase gene ORF74 is related to G protein-coupled receptors, particularly interleukin-8 (IL-8) receptors. ORF74 activates the inositol phosphate/phospholipase C pathway and the downstream mitogen-activated protein kinases, JNK/SAPK and p38. We show here that ORF74 also activates NF-kappaB independent of ligand when expressed in KS-derived HHV-8-negative endothelial cells or primary vascular endothelial cells. NF-kappaB activation was enhanced by the chemokine GROalpha, but not by IL-8. Mutation of Val to Asp in the ORF74 second cytoplasmic loop did not affect ligand-independent signaling activity, but it greatly increased the response to GROalpha. ORF74 upregulated the expression of NF-kappaB-dependent inflammatory cytokines (RANTES, IL-6, IL-8, and granulocyte-macrophage colony-stimulating factor) and adhesion molecules (VCAM-1, ICAM-1, and E-selectin). Supernatants from transfected KS cells activated NF-kappaB signaling in untransfected cells and elicited the chemotaxis of monocytoid and T-lymphoid cells. Expression of ORF74 conferred on primary endothelial cells a morphology that was strikingly similar to that of spindle cells present in KS lesions. Taken together, these data, demonstrating that ORF74 activates NF-kappaB and induces the expression of proangiogenic and proinflammatory factors, suggest that expression of ORF74 in a minority of cells in KS lesions could influence uninfected cells or latently infected cells via autocrine and paracrine mechanisms, thereby contributing to KS pathogenesis.

Cells, Cultured↗

PubMed2000

Lipopolysaccharides of Rhizobium etli strain G12 act in potato roots as an inducing agent of systemic resistance to infection by the cyst nematode Globodera pallida.

Recent studies have shown that living and heat-killed cells of the rhizobacterium Rhizobium etli strain G12 induce in potato roots systemic resistance to infection by the potato cyst nematode Globodera pallida. To better understand the mechanisms of induced resistance, we focused on identifying the inducing agent. Since heat-stable bacterial surface carbohydrates such as exopolysaccharides (EPS) and lipopolysaccharides (LPS) are essential for recognition in the symbiotic interaction between Rhizobium and legumes, their role in the R. etli-potato interaction was studied. EPS and LPS were extracted from bacterial cultures, applied to potato roots, and tested for activity as an inducer of plant resistance to the plant-parasitic nematode. Whereas EPS did not affect G. pallida infection, LPS reduced nematode infection significantly in concentrations as low as 1 and 0.1 mg ml(-1). Split-root experiments, guaranteeing a spatial separation of inducing agent and challenging pathogen, showed that soil treatments of one half of the root system with LPS resulted in a highly significant (up to 37%) systemic induced reduction of G. pallida infection of potato roots in the other half. The results clearly showed that LPS of R. etli G12 act as the inducing agent of systemic resistance in potato roots.

Animals↗