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Background: We report the influence of race on transplant outcomes in the Department of Defense (DOD) system., Methods: Retrospective cohort analysis of all kidney transplants performed at WRAMC from 1996 to 2005. Kaplan-Meier analysis was used to assess for differences in graft survival, and Cox regression was used to calculate adjusted hazard ratios for graft loss. For our analyses, we used the cutoff of 6 years (year 2000) when we introduced thymoglobulin induction; maintenance immunosuppression consisted of mycophenolate mofetil and tacrolimus, and rapid steroid taper (completed withdrawal at 6 weeks) was used for all patients., Results: There were 220 transplants (91 Blacks, 107 Caucasians and 22 Asians). Because the curve for graft survival for Blacks over time violated the proportional hazards assumption (at 6 years post-transplant), analysis was segregated into two segments. Through 6 years of follow-up, graft survival was 77% for Blacks and 81% for non-Blacks (p = 0.74 by log rank). Through 9 potential years of follow-up, graft survival for Blacks was 56% and 78% for Whites (p = 0.005). In Cox regression analysis, Black race, compared with non-Black race, was not significantly associated with graft loss at 6 years, but was significantly associated with graft loss occurring after 6 years., Conclusions: In the DOD health system, no significant differences were seen in graft survival among recipients of different races at 6 years. Black recipients who received a kidney transplant before the year 2000 showed decreased graft survival compared to non-Blacks. This was consistent with change in immunosuppressive regimen in our institution with the introduction of thymoglobulin induction and maintenance therapy with tacrolimus, mycophenolate mofetil and withdrawal of prednisone at 6 weeks.

The characterization of any detected antibodies provides detailed information that can be critical to understanding the significance of an immune response. The BIAcore immunoassay provides a straightforward means of characterizing many aspects of the immune response including antibody concentration, specificity, binding affinity, and the presence of isotypes. One important aspect of the immune response is determination of neutralizing capability, which requires a biological assay. The ultimate clinical significance of an immune response can only be fully understood when data from antibody characterization are coupled with clinical data from the patient. Some of the factors that can contribute to the clinical significance of an immune response are: (i) magnitude of the immune response (concentration of antibodies detected); (ii) duration of the immune response (continuous antibody production or sporadic and not sustained); (iii) correlation with any adverse events; (iv) correlation with a change in pharmacokinetics (either mediating sustained circulation or enhanced clearance of the drug); (v) biological neutralization of the drug; (vi) biological neutralization of an endogenous protein. Full characterization of the immune response requires the incorporation of antibody assays, pharmacokinetic assays, and clinical data.

The determination of antibody formation in response to a therapeutic product requires that a variety of data be evaluated. In addition to examining immuno-assay and bioassay results, it is important to determine any clinical relevance. By also examining pharmacokinetic data as well as other clinical results, an evaluation can be made as to whether any clinically relevant antibodies were generated. To help in this evaluation, it is important to fully characterize the antibodies that are generated. Both the BIAcore and IGEN platforms are powerful tools for determining if antibodies have been produced in a subject The BIAcore is also able to characterize these antibodies as to isotype, relative concentration, and relative affinity. The bioassay result can identify serum samples that contain an agent capable of inhibiting a biological effect of a drug. When combined with the results of an immuno-assay, it is possible to determine if the antibodies are capable of neutralizing the drug.

Biosensor instruments, such as the BIACORE, are gaining popularity for analysing serum samples for the presence of antibodies. These instruments offer several advantages in the detection and subsequent characterization of clinically relevant antibodies generated in response to administration of therapeutic proteins. Much like other common immunoassay platforms, immobilized ligand is used to capture antibodies. Unlike conventional approaches, the ligand is immobilized to the surface of a biosensor chip, with detection based upon surface plasmon resonance. This assay platform, therefore, does not require reporter molecules such as enzymes, fluorochromes or radioisotopes that are common to conventional immunoassay methodologies. Additional desirable features of the biosensor platform include real-time detection of the binding of antibody to ligand (for kinetic measurements) as well as straightforward characterization of antibody isotype, specificity and relative concentration. This is all performed with minimum serum requirements (typically 10 microlitres per sample analysed) in a fully automated environment. The unique features of the biosensor instrument warrant that these assays are referred to as biosensor immunoassays to clearly distinguish them from more conventional immunoassay methodologies, such as ELISA.

Background: Lung cancer is the most common cause of cancer death in women in the USA. Lung cancer arising during pregnancy is rare and has been reported only 15 times since the 1950s. However, the use of chemotherapy for lung cancer during pregnancy has not previously been reported., Methods: The history, treatment and outcome of a patient with stage IV non-small-cell lung carcinoma (NSCLC) diagnosed during pregnancy is presented. Previous published reports on lung cancer were retrieved by a literature search of Medline and Cancerlit., Results: A 31-year-old woman was diagnosed as having stage IV NSCLC with bilateral pulmonary involvement when 26 weeks pregnant. Her shortness of breath progressed to dyspnea at rest on 100% inspired oxygen. Therefore, she was treated with systemic chemotherapy using cisplatin and vinorelbine. Despite this treatment, her oxygenation declined further over the next 4 days and thus the baby was delivered via cesarean section after 27 weeks of gestation. Four cycles of vinorelbine and cisplatin have now been administered. Following this treatment, the patient has experienced a significant clinical improvement and no longer requires supplemental oxygen. No chemotherapy-related adverse effects have been noted in the baby. In the 15 previously reported patients with concurrent lung cancer and pregnancy, chemotherapy administration during pregnancy has not been described., Conclusions: Treatment of lung cancer with chemotherapy during pregnancy should be considered on an individual basis with regard to the stage of the cancer and the maturity of the fetus. To our knowledge, the case presented here is the first report of a woman receiving chemotherapy for lung cancer while pregnant., (Copyright 2001 S. Karger AG, Basel)

Biosensor and electrochemiluminescent (ECL) assays are replacing enzyme-linked immunosorbent assays (ELISAs) at Schering-Plough as immunoassays of choice to monitor cytokine levels and detect anti-cytokine antibody responses during cytokine therapy. These new assays provide increased sensitivity and a better correlation with biological assays. Biosensor assays using the BIACORE 2000 (BIACORE, Uppsala, Sweden) are being adopted to support preclinical and clinical trials for the detection of antibodies capable of binding to IL-10 and IL-4. Significant advantages when using a biosensor assay are that real-time and label-free detection permit increased throughput and direct detection of binding interactions which enables detection of low affinity antibodies that are not detected by ELISA. The ECL assays using the ORIGEN Analyser (IGEN, Gaithersburg, MD) that we have implemented to replace existing ELISAs for quantification of serum IL-10 and serum interferon alfa levels are more sensitive and less subject to matrix effects. Data obtained during the validation of these assays are described.