Blastokinin or uteroglobin (UG) is a steroid-inducible, evolutionarily conserved, multifunctional protein secreted by the mucosal epithelial of virtually all mammals. It is present in the blood and in other body fluids including urine. An antigen immunoreactive to UG antibody is also detectable in the mucosal epithelia of all vertebrates. UG-binding proteins (putative receptor), expressed on several normal and cancer cell types, have been characterized. The human UG gene is mapped to chromosome 11q12.2 13.1, a region that is frequently rearranged or deleted in many cancers. The generation of UG knockout mice revealed that disruption of this gene causes: (i) severe renal disease due to an abnormal deposition of fibronectin and collagen in the glomeruli; (ii) predisposition to a high incidence of malignancies; and (iii) a lack of polychlorinated biphenyl binding and increased oxygen toxicity in the lungs. The mechanism(s) of UG action is likely to be even more complex as it also functions via a putative receptor-mediated pathway that has not yet been clearly defined. Molecular characterization of the UG receptor and signal transduction via this receptor pathway may show that this protein belongs to a novel cytokine/chemokine family.

To study the effect of genetic immunization on transgenic expression of hepatitis C virus (HCV) proteins, we evaluated the immunological response of HCV transgenic mice to HCV expression plasmids. FVB/n transgenic mice expressing HCV structural proteins (core, E1, and E2) and wild-type (WT) FVB/n mice were immunized intramuscularly with plasmids expressing core (pHCVcore) or core/E1/E2 (pHCVSt). After immunization, HCV-specific humoral and cellular immune response was studied. Both WT and transgenic mice immunized with either HCV construct produced antibodies and exhibited T-cell proliferative responses against core or envelope. In WT mice immunized with pHCVSt, cytotoxic T-lymphocyte (CTL) activities were detected against E2 but not against core or E1, whereas strong CTL activities against core could be detected in WT mice immunized with pHCVcore. In pHCVSt-immunized, transgenic mice, CTL activities against the core or envelope were completely absent, but core-specific CTL activities could be detected in pHCVcore-immunized transgenic mice. A similar pattern of immune responses was also observed in other mouse strains, including a transgenic line expressing human HLA-A2.1 molecules (AAD mice). Despite the presence of a peripheral cellular immunity against HCV, no liver pathology or lymphocytic infiltrate was observed in these transgenic mice. Our study suggests a hierarchy of CTL response against the HCV structural proteins (E2 > core > E1) in vivo when the proteins are expressed as a polyprotein. The HCV transgenic mice can be induced by DNA immunization to generate anti-HCV antibodies and anticore CTLs. However, they are tolerant at the CTL level against the E2 protein despite DNA immunization.Transgenic models have been developed to study the mechanisms of tolerance and their implications for autoimmune or other immune-mediated diseases. In this regard, transgeneencoded neo-self antigen coupled with the corresponding Tcell receptor transgene has been particularly valuable (4,20,23,35). In addition to central thymic selection, peripheral tolerance mechanisms, including peripheral deletion, anergy, and ignorance have been defined (5,10,27,28,36). In the latter case, it is often possible to break tolerance and induce autoimmunity, leading to immune-mediated tissue injury. Expression of neo-self antigens in the liver presents a particular interesting scenario because of the putative toleragenic role of the liver in immune response and the unique anatomy of the liver in which the fenestrated vasculature allows direct access of hepatocytes to circulating T cells (25). This intriguing question has been addressed in several transgenic models in which central and peripheral deletion of reactive T cells appears to confer a robust tolerance to the neo-self antigen expressed in the transgenic liver. In situations whereby peripheral anergy or ignorance induction is operative, tolerance at the T-cell level can be broken by either viral infection or dendritic cell or DNA immunization (23,31,35,37). However, induction of hep...

Background Infantile neuronal ceroid lipofuscinosis (INCL) is a devastating neurodegenerative storage disease caused by palmitoyl-protein thioesterase-1 (PPT1) deficiency. PPT1 deficiency impairs degradation of palmitoylated proteins (constituents of ceroid) by lysosomal hydrolases. Consequent lysosomal ceroid accumulation leads to neuronal injury, resulting in rapid neurodegeneration and childhood demise. As part of a project studying treatment benefits of a combination of cysteamine bitartrate and N-acetylcysteine, we made serial measurements of patients’ brain volumes using MRI. Methods Ten INCL patients participating in a treatment/follow-up study underwent brain MRI that included high resolution T1-weighted images. After manual placement of a mask delineating the surface of the brain, a maximum-likelihood classifier was applied to determine total brain volume, further subdivided as cerebrum, cerebellum, brainstem, and thalamus. Patients’ brain volumes were compared to those of a normal population. Results Major subdivisions of the brain followed similar trajectories with different timing. The cerebrum demonstrated early, rapid volume loss, and may never have been normal postnatally. The thalamus dropped out of the normal range around age 6 months, cerebellum around age 2 years, and brainstem around age 3 years. Discussion Rapid cerebral volume loss was expected based upon previous qualitative reports. Because our study did not include a non-treatment arm, and because progression of brain volumes in INCL has not previously been quantified, we could not determine whether our intervention had a beneficial effect on brain volumes. However, the level of quantitative detail in this study allows it to serve as a reference for evaluation of future therapeutic interventions.

There is growing interest in pooling specimens across subjects in epidemiologic studies, especially those involving biomarkers. This paper is concerned with regression analysis of epidemiologic data where a binary exposure is subject to pooling and the pooled measurement is dichotomized to indicate either that no subjects in the pool are exposed or that some are exposed, without revealing further information about the exposed subjects in the latter case. The pooling process may be stratified on the disease status (a binary outcome) and possibly other variables but is otherwise assumed random. We propose methods for estimating parameters in a prospective logistic regression model and illustrate these with data from a population-based case-control study of colorectal cancer. Simulation results show that the proposed methods perform reasonably well in realistic settings and that pooling can lead to sizable gains in cost efficiency. We make recommendations with regard to the choice of design for pooled epidemiologic studies.

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Reference curves are commonly used to identify individuals with extreme values of clinically relevant variables or stages of progression which depend naturally on age or maturation. Estimation of reference curves can be complicated by a technical limit of detection (LOD) that censors the measurement from the left, as is the case in our study of reproductive hormone levels in boys around the time of the onset of puberty. We discuss issues with common approaches to the LOD problem in the context of our pubertal hormone study, and propose a two-part model that addresses those issues. One part of the proposed model specifies the probability of a measurement exceeding the LOD as a function of age. The other part of the model specifies the conditional distribution of a measurement given that it exceeds the LOD, again as a function of age. Information from the two parts can be combined to estimate the identifiable portion (i.e., above the LOD) of a reference curve and to calculate the relative standing of a given measurement above the LOD. Unlike some common approaches to LOD problems, the two-part model is free of untestable assumptions involving unobservable quantities, flexible for modeling the observable data, and easy to implement with existing software. The method is illustrated with hormone data from the Third National Health and Nutrition Examination Survey.