IntroductionMononuclear cell recruitment to an allograft is a classic hallmark of cellular rejection. At least in broad terms, such leukocyte recruitment from the vascular pool across activated endothelial cells and into tissues is now reasonably well understood (1). Thus, leukocytes roll along selectin-expressing endothelium adjacent to a chemoattractant source, attach more firmly, change shape, migrate between adjacent endothelial cells as a result of integrin and other adhesion molecule binding, and migrate through extravascular tissues along chemotactic gradients to reach their destination. The latter chemokine/chemokine receptor phase is the least understood, with little in vivo data available. However, given the burgeoning field of chemokine biology, dissecting which molecules are generated in a given inflammatory setting, and especially the nature of chemokine receptors responsible for leukocyte recruitment, might well prove key to developing better therapeutic strategies for the prevention and treatment of allograft rejection. The current literature on chemokine receptor expression in organ transplants is limited to 2 papers noting expression of CXCR4 (ref. The current studies involve serial analysis of intragraft chemokine and chemokine receptor expression within completely MHC-mismatched mouse cardiac allografts. On the basis of our initial data, in which several chemokine receptors and their ligands were associated with host mononuclear cell infiltration, we undertook a detailed analysis of the significance of 1 of the more highly expressed chemokine receptors, CCR1 (4), which binds RANTES, macrophage inflammatory protein 1-alpha (MIP-1α), and various monocyte chemoattractant proteins (MCPs). Our studies demonstrate that compared with control CCR1 +/+ mice, CCR1 -/-mice show significantly delayed, or in some cases an absence of, acute or chronic rejection, such that targeting of CCR1 may eventually prove of therapeutic significance clinically. Although mononuclear cell infiltration is a hallmark of cellular rejection of a vascularized allograft, efforts to inhibit rejection by blocking leukocyte-endothelial cell adhesion have proved largely unsuccessful, perhaps in part because of persistent generation of chemokines within rejecting grafts. We now provide, to our knowledge, the first evidence that in vivo blockade of specific chemokine receptors is of therapeutic significance in organ transplantation. Inbred mice with a targeted deletion of the chemokine receptor CCR1 showed significant prolongation of allograft survival in 4 models. First, cardiac allografts across a class II mismatch were rejected by CCR1 +/+ recipients but were accepted permanently by CCR1 -/-recipients. Second, CCR1 -/-mice rejected completely class I-and class II-mismatched BALB/c cardiac allografts more slowly than control mice. Third, levels of cyclosporin A that had marginal effects in CCR1 +/+ mice resulted in permanent allograft acceptance in CCR1 -/-recipients. These latter allografts showed no sign of chronic rejection 50-...

P roteomics is the study of protein expression in a tissue or biological fluid. Comparison of protein patterns in biological fluids between healthy individuals and patients with disease is increasingly being used both to discover biological markers of disease (biomarkers) and to identify biochemical processes important in disease pathogenesis. Although currently available tests for urine proteins measure either the total level of urine protein or the presence of a single protein species, emerging proteomic technologies allow simultaneous examination of the patterns of multiple urinary proteins and their correlation with individual diagnoses, response to treatment or prognosis. Analysis of the various protein constituents of urine may suggest novel, noninvasive diagnostic tests, therapeutic guidance, and prognostic information for patients and clinicians.In this review, we describe the current practice of urine protein testing and the emerging technologies that are being used for analysis of the urinary proteome. BackgroundNormally, the low-molecular-weight proteins and albumin that are filtered from plasma into the early tubular fluid are almost completely reabsorbed and catabolized in the proximal tubules. As a result, daily urinary protein excretion is less than 150 mg/day, of which about 10 mg is albumin. In patients with physiologic proteinuria, the proteins excreted include mucoproteins (mainly Tamm-Horsfall protein), blood-group proteins, albumin, immunoglobulins, mucopolysaccharides and very small amounts of hormones and enzymes. Historically, proteinuria of more than 150 mg/day was regarded as abnormal. However, it is now appreciated that early renal disease is often characterized by low-level albuminuria (between 30 and 300 mg/day).1 This condition is termed microalbuminuria because the concentration of albumin is below the detection limit of traditional assays. Protein or albumin excretion greater than 300 mg/day represents overt proteinuria or macroalbuminuria; at this level, the result of standard urine dipstick testing becomes positive.Pathological proteinuria can be divided into 3 categories: glomerular proteinuria, tubular proteinuria and overload proteinuria.2 Glomerular proteinuria results from an increase in the permeability of the glomerular capillary wall to macromolecules (particularly albumin) and usually results from glomerular disease. Tubular proteinuria results from reduced reabsorption of proteins that are normally present in the glomerular filtrate or from excretion of proteins derived from injured tubular epithelial cells. It is usually caused by diseases of the tubulointerstitium. Overload proteinuria is due to an excess of low-molecular-weight proteins that are normally reabsorbed by the proximal tubules. These proteins are most often immunoglobulin light chains (in the plasma cell dyscrasias), although lysozyme (in myelomonocytic leukemia), myoglobin (in rhabdomyolysis) or hemoglobin (in intravascular hemolysis) may also be identified.Under normal conditions, urinary proteins exis...

We hypothesized that screening for nonadherence to antihypertensive treatment using liquid chromatography-tandem mass spectrometry–based biochemical analysis of urine/serum has therapeutic applications in nonadherent hypertensive patients. A retrospective analysis of hypertensive patients attending specialist tertiary care centers was conducted in 2 European countries (United Kingdom and Czech Republic). Nonadherence to antihypertensive treatment was diagnosed using biochemical analysis of urine (United Kingdom) or serum (Czech Republic). These results were subsequently discussed with each patient, and data on follow-up clinic blood pressure (BP) measurements were collected from clinical files. Of 238 UK patients who underwent biochemical urine analysis, 73 were nonadherent to antihypertensive treatment. Their initial urinary adherence ratio (the ratio of detected to prescribed antihypertensive medications) increased from 0.33 (0–0.67) to 1 (0.67–1) between the first and the last clinic appointments. The observed increase in the urinary adherence ratio in initially nonadherent UK patients was associated with the improved BP control; by the last clinic appointment, systolic and diastolic BPs were ≈19.5 and 7.5 mm Hg lower than at baseline (P=0.001 and 0.009, respectively). These findings were further corroborated in 93 nonadherent hypertensive patients from Czech Republic—their average systolic and diastolic BPs dropped by ≈32.6 and 17.4 mm Hg, respectively (P<0.001), on appointments after the biochemical analysis. Our data show that nonadherent hypertensive patients respond to liquid chromatography–tandem mass spectrometry-based biochemical analysis with improved adherence and significant BP drop. Such repeated biochemical analyses should be considered as a therapeutic approach in nonadherent hypertensive patients.