Combination effect of vaccination with IL2 and IL4 cdna transfected cells on the induction of a therapeutic immune response against lewis lung carcinoma cells

In order to develop a more effective method of immunotherapy we have transfected mouse interleukin-2 (IL2) or mouse interleukin-4 (IL4) cDNA into a spontaneous non-immunogenic murine lung cancer, Lewis lung carcinoma (LLC). IL2 cDNA transfection more strongly decreases tumorigenicity of LLC than IL4 cDNA transfection. Recombinant-human-IL2 treatment of mice that were transplanted with untransfected LLC could not prolong their survival. In contrast, vaccination with IL2-cDNA-transfected LLC (LLC-IL2) and LLC-ILZ mixed with IL4-cDNA-transfected LLC (LLC-114) could significantly suppress tumor growth of LLC in a tumor-specific manner. The vaccination with LLC-IL2 mixed with the same number of LLC-IL4 cells was more suppressive to the growth of LLC than that with LLC-ILZ cells alone, while LLC-IL4 vaccination alone was ineffective. Nude, severe-combined-immune-deficient (SCID) and beige mice were unable to reject LLC-IL2 cells. However, immunodeficient mice responded to LLC-IL2, but not to LLC, since their survival times after transplantation with LLC-IL2 cells were significantly longer than the survival time of normal or immunodeficient mice transplanted with untransfected LLC cells. We conclude that vaccination with IL2-producing tumors and, with more pronounced effect, in combination with IL4-producing tumors, is able to induce an immune response to this normally non-immunogenic tumor. Tumor rejection appears to be achieved by the combined activity of CTL and NK cells. This strategy has potential for new immunotherapeutic interventions in cancer patients.     

The “functional muscle-bone unit”: a two-step diagnostic algorithm in pediatric bone disease

Bone densitometric data often are difficult to interpret in children and adolescents because of large inter- and intraindividual variations in bone size. Here we propose a functional approach to bone densitometry that addresses two questions. Is bone strength normally adapted to the largest physiological loads, i.e., muscle force? Is muscle force adequate for body size? Previously published reference data were used to evaluate results from children with preterminal chronic renal failure (n=11) and renal transplant recipients (n=15). In both groups mean height, muscle cross sectional area (MCSA), and bone mineral content (BMC) were low for age, but muscle MCSA was normal for height. In the renal transplant recipients the BMC/muscle MCSA ratio was decreased (P <0.05), suggesting that bone cortical strength was not adapted adequately to muscle force. In contrast, chronic renal failure patients had a normal cortical BMC/muscle MCSA ratio, suggesting that their musculoskeletal system was adapted normally to their (decreased) body size.     

Triple-coated stents (Hirudin/Iloprost/Paclitaxel): an in vitro approach for characterizing the antiproliferative potential of each individual compound

BACKGROUND: Hirudin (H)/iloprost (I)/paclitaxel (P)-coated stents represent a multifactorial approach to reducing the proliferative response caused by ballooning and stenting. The study presented compares the net effect of each individual compound of HIP-coated stents with the summed effect of the compounds in the stent coating. METHODS AND RESULTS: For proliferation prescreening studies, human coronary smooth muscle cells were incubated with H (0.005-500 microg/ml), I (0.00001-1 microg/ml), and P (0.0001-10 microg/ml). After 5 days, cell number was studied in a cell analyzer system. Secondly, 8-mm stents were coated with (1) HI, (2) HIP-10 microg/20 microg/40 microg (HIP5%/10%/20%), (3) P-40 microg (P), (4) IP-40 microg (IP), and (5) HP-40 microg (HP). After 5 days, the effect on cell proliferation and cytoskeletal structures was studied. No antiproliferative effect was found after incubation with H; significant inhibition was seen after incubation with I (p<0.05) or lipophilically dissolved P (p<0.001). After 5 days incubation with HIP5%-, HIP10%-, HIP20%-, P20%-, IP20%-, and HP20%-coated stents, cell proliferation was inhibited by 55.5% (p<0.05), 61% (p<0.05), 57.9% (p<0.05), 59.5% (p<0.001), 59.8% (p<0.001), and 63.3% (p<0.001), respectively. HI- and HIP-coated stents caused a severe destruction of the cytoskeletal structures smooth muscle alpha-actin and alpha-tubulin; despite the destruction, vital cells could be identified with positive FDA staining. CONCLUSIONS: Although both lipophilically dissolved P and hydrophilically dissolved I contributed to the antiproliferative effect, no additive effect of the two compounds was detected. In vivo P can be released more easily from the coating material due to the permanent lipophilic contact of the stent struts with the vessel wall. The current study is the first report on a clear and uncomplicated technique to obtain information on the antiproliferative potential of coated stents before large experimental studies are initiated.     

Radiologic morphology of low-grade primary central nervous system lymphoma in immunocompetent patients

BACKGROUND AND PURPOSE: Primary central nervous system lymphomas (PCNSLs) are usually high-grade and are rarely low-grade non-Hodgkin lymphomas (NHLs). On MR imaging, PCNSLs typically present as contrast-enhancing lesions in contact with the subarachnoid space without evidence of necrosis. We evaluated the radiologic morphology and clinical characteristics of low-grade PCNSLs, hypothesizing that they may differ from high-grade PCNSLs. METHODS: Records were reviewed from 332 patients screened for inclusion in 3 multicenter prospective trials. MR imaging scans were obtained from all patients and were centrally reviewed by 2 consultant neuroradiologists. RESULTS: Ten patients (3%) with low-grade PCNSLs (7 men and 3 women; median age, 59 years; age range, 19-61 years) were identified. Four patients had one lesion, 2 patients 2 lesions, and 4 patients had multiple lesions. The following radiologic features infrequently seen in high-grade PCNSLs were found in a substantial proportion of patients: location in deep structures or spine (n = 6); lack of periventricular location (n = 5); hyperintensity on T2-weighted images (n = 10); moderate or absent contrast enhancement (n = 6); and heterogeneous contrast enhancement (n = 5). In 8 patients, >2 of these features were present in at least one lesion, and, thus, the radiologic appearance was assessed atypical of high-grade PCNSLs. The atypical radiologic appearance in combination with atypical or mild symptoms resulted in a false or delayed diagnosis. CONCLUSION: Low-grade PCNSLs may have a variable and atypical radiologic morphology compared with high-grade PCNSLs with the risk of false or delayed diagnosis.     

The role of current product release criteria for identification of human islet preparations suitable for clinical transplantation

BACKGROUND: Alloimmunity, autoimmunity, and nonspecific inflammation are known to be potential determinants for long-term islet survival and insulin independence. Sufficient islet mass is a key determinant. But islet engraftment and posttransplant survival may also depend on functional characteristics of the graft. This study investigated the significance of current product release criteria for the transplantation outcome. METHODS: Fourty five consecutive transplanted human islet preparations and their functional outcomes were analyzed. Islet mass was determined according to standard criteria: purity by light microscopy, viability by dye exclusion and Insulin secretory response to static glucose incubation. Islet graft function was monitored for > or = 1 year. Islet function was defined as full (FF), partial (PF), or nonfunction (NF) based on serum C-peptide levels and insulin independence. RESULTS: All islet grafts displayed primary function. Islet mass [IEQ/kg BW]: 7331.3 +/- 679.7 (FF), 5821.3 +/- 546.7 (PF), 6468.6 +/- 658.5 (NF), (FF vs PF p = .032) Purity [%] 86.9 +/- 3.1 (FF), 76.0 +/- 2.87 (PF), 88.2 +/- 2.3 (NF) (FF vs PF P =.045, PF vs NF, P = 0.01). (4) Viability [%]:89.2 +/- 2 (FF), 86.2 +/- 1.7 (PF), 87.3 +/- 1.8 (NF) (ns). Stimulation index (SI): 20 +/- 6.3 (FF), 80.2 +/- 28.2 (PF), 21.6 +/- 3.5 (NF) (ns) No correlation was observed between SI and any other parameter nor between SI and C-peptide levels. Islet mass significantly correlated with C-peptide levels at 6 and 12 months after transplantation for functioning grafts. CONCLUSIONS: Stringent product release criteria allow identification of islet preparations suitable for clinical transplantation. However, currently used parameters are not predictive of long-term graft function, indicating that further refined quality assessments including apoptosis and resistance to early inflammation, are required to assess the primary engrafted islet mass.