In vivo plasmid electroporation induces tumor antigen-specific CD8+ T-cell responses and delays tumor growth in a syngeneic mouse melanoma model

Plasmid DNA-based molecular cancer vaccines generally suffer from suboptimal immunogenicity. One of the key limitations is insufficient level of gene expression, which was surmounted in our approach by using the novel technique of in vivo plasmid electroporation-enhanced vaccination (electrovaccination). Electrovaccination with plasmids encoding the full-length autologous melanocyte antigen tyrosinase-related protein-2 induced limited melanocyte destruction in a subset of mice. Despite examples of vitiligo, vaccinated mice were not protected from a subsequent challenge of B16F10M melanoma cells. Novel constructs were then designed and submitted to a functional screen. Best performance was obtained when the relevant H-2K(b)-restricted epitope SVYDFFVWL was placed into a context of sequences of the HLA-Cw3 molecule. After animals were electrovaccinated using this construct, direct enzyme-linked immunospot analysis of peripheral blood mononuclear cells indicated that very high numbers of T cells recognizing the specific tyrosinase-related protein-2 epitope were generated. CD8+ T cells isolated from the spleen also displayed a high degree of antigen-specific reactivity and vigorously reacted toward unmodified B16F10M cells. In vivo protective effects of this construct were demonstrated in mice using two different models; outgrowth of s.c. implanted B16F10M tumor cells was significantly delayed, and vaccinated mice developed no or only very few tumor nodules in an i.v. lung metastasis model. Thus, improved antigen vectors delivered by highly effective gene transfer methods may form the basis for future human applications.     

Differences in adherence and motivation to HIV therapy—two independent assessments in 1998 and 2002

Objective The aim of this study was to compare the level of adherence and motivation in two independent cross-sectional samples of HIV-infected patients conducted in 1998 and 2002, and to investigate the relationship between adherence and motivation.Method Consecutive HIV-infected patients on treatment at a Swedish clinic were asked to complete an anonymous questionnaire. In 1998, 60 patients participated and in 2002, 53 participated. In 2002, the 9-item Morisky Medication Adherence Scale (MMAS) was added to the questionnaire set.Main outcome measure Self-reported adherence and motivation.Results In 1998, 28.1% of the respondents were considered adherent, while the corresponding proportion was 57.4% in 2002 (P = 0.002). The mean summary score for MMAS was 10.7 in 2002 (13 = perfect adherence). The proportion considered motivated were 22.4% in the 1998 survey and 41.3% in 2002 (P = 0.038). Of the respondents considered motivated in the 2002 survey, 46.7% scored the maximum summary score on the MMAS, while 8.7% of the non-motivated respondents did so (P = 0.016).Conclusion The respondents in 2002 were more adherent and motivated than the respondents in 1998 and a relationship between motivation and adherence was found. The difference in adherence and motivation might be due to a new treatment model at the clinic.     

Detection of maternal deoxyribonucleic acid in umbilical cord plasma by using fluorescent polymerase chain reaction amplification of short tandem repeat sequences.

OBJECTIVE: Umbilical cord blood is a source of hematopoietic stem cells for transplantation. Although the first clinical applications have been encouraging, concern has been raised about contamination of umbilical blood by maternal cells, which might constitute a theoretical risk of graft-versus-host disease. The aim of this study was to assess the frequency of maternal deoxyribonucleic acid (DNA) contamination in umbilical cord plasma by using fluorescent polymerase chain reaction amplification of highly polymorphic short tandem repeat DNA markers. STUDY DESIGN: Fifty-seven mother/child pairs were tested for the presence of maternal DNA sequences in cord plasma. After delivery, cord blood samples were collected via gravity. Maternal specific alleles were detected by using polymerase chain reaction amplification of 9 highly polymorphic short tandem repeat markers (D21S11, D21S1411, D21S1412, D18S386, D18S535, MBP-A, MBP-B, D13S631, and D13S634). RESULTS: All 57 mother-child pairs were informative for the identification of uniquely maternal alleles in at least 2 of 9 different short tandem repeat markers used per case. Uniquely maternal DNA sequences were found in 43 of 57 (75%) cord plasma samples. CONCLUSION: The results of our study demonstrate that maternal DNA is present in the majority of umbilical cord blood plasma samples. The technique described herein might have application in the screening of umbilical cord blood samples for the presence of contaminating maternal genetic material.     

Association of disease progression and poor overall survival with detection of circulating tumor cells in peripheral blood of patients with metastatic breast cancer

The aim of this study was to define the frequency and clinical relevance of cytokeratin positive metastatic tumor cells in the peripheral circulation of patients with stage IV breast cancer. Peripheral blood was collected from 32 consecutive patients with metastatic breast cancer and 23 healthy donors. Tumor cells were enriched using positive selection with anti-HEA125-microbeads and cytospins were prepared of the positive selection eluate. Slides were incubated with a Fab2 fragment of the pancytokeratin antibody A45-B/B3 conjugated with alkaline phosphatase (AKP) and a CAM5.2-AKP monoclonal antibody and developed with an alkaline phosphatase anti-alkaline phosphate reaction (APAAP). All samples were evaluated using light microscopy and an automated image analysis system. In 8/32 (25%) patients cytokeratin positive (CK+) cells could be detected after anti-HEA125 enrichment in the peripheral blood whereas in none out of 23 healthy donors. One to 1000 (median 5) positive cells per patient sample were observed and cluster of tumor cells in one patient. Automated image analysis was as powerful in detecting micrometastases as conventional light microscopy. All patients with CK+ cells in the peripheral circulation (8/8, 100%) showed progressive disease at the time-point of blood draw whilst only 9/24 (37.5%) showed disease progression without detection of positive cells. The median overall survival of CK+ patients was 4+/-2 months compared to 13+/-7 months of CK- patients (p<0.001). CK+ cells are detectable in the peripheral circulation of 25% of patients with metastatic breast cancer after positive selection with anti-HEA125. Detection of tumor cells in the peripheral circulation might be correlated with progression of disease and shorter overall survival.     

Immune recovery after conventional and non-myeloablative allogeneic stem cell transplantation

The immune recovery of 66 patients undergoing allogeneic stem cell transplantation with either conventional or non-myeloablative conditioning regimen was studied. Infections post-transplant were enumerated and quantitative immunoglobuilins (IgG, IgA, IgM) and lymphocyte sub-sets 3, 6 and 12 months post-transplant were measured. A significant difference was found in the immunologic recovery of non-myeloablative and conventional ASCT in the patient population. The T-helper cell reconstitution was significantly faster after NMA than conventional transplantation and the recovery of B cells was faster after conventional transplantation. Regarding immunoglobulin levels, a faster recovery of IgM levels after NMA-ASCT and a delayed recovery of IgA levels was observed in both groups. These were accompanied by a significant difference in the frequency and severity of infectious episodes.     

Interstitial lung disease in mixed connective tissue disease

INTRODUCTION: The authors analyzed the incidence of interstitial lung disease in mixed connective tissue disease. They were seeking an answer to the following problems: the nature of the pathological course of mixed connective tissue disease complicated by and the therapy to be used in interstitial lung disease. PATIENTS AND METHODS: 179 patients were followed up during a period of 15.9 +/- 6.1 years. Interstitial lung disease was diagnosed using high resolution computed tomography. The diagnosis of interstitial lung disease was not obvious in 5 patients thus open lung biopsy was performed, which confirmed common interstitial pneumonitis. The patients were followed-up, and the data of computed tomography and respiratory function tests were detected 6 months, and then 4 years after the acute lung disease complicated by mixed connective tissue disease. RESULTS: Out of the 179 mixed connective tissue disease patients 96 (53.6%) had interstitial lung disease. The onset of interstitial lung disease was the most frequent in the 2-4 years of the disease. Four years after the first appearance of interstitial lung disease severe fibrosis was diagnosed in 24 patients (25%). A honey comb formation in the lung developed only in one patient. For the treatment of interstitial lung disease, corticosteroid treatment had to be combined with cyclophosphamide in 51 cases. In 4 patients (24%), pulmonary arterial hypertension evolved 2-4 years following interstitial lung disease. The high pulmonary arterial pressure decreased using pulsed corticosteroid treatment, cyclophosphamide, prostacyclin analogue, anticoagulants therapy and the 4 patients stay alive. The pulmonary arterial hypertension was caused by obliterative vasculopathy. CONCLUSION: Pulmonary involvement is found in more than half of the patients with mixed connective tissue disease. Early diagnosis of interstitial lung disease is possible by computed tomography. Interstitial lung disease can be treated by the combination of corticosteroids and cyclophosphamide. The authors were the first to detect the coexistence of interstitial lung disease and pulmonary arterial hypertension in mixed connective tissue disease. Subsequent respiratory alterations in these patient necessitate regular patient follow up.