Citations

We describe a strategy to “revive” putatively pathogenic T cells from frozen specimens of human inflammatory target organs. To distinguish pathogenic from irrelevant bystander T cells, we focused on cells that were ( i ) clonally expanded and ( ii ) in direct morphological contact with a target cell. Using CDR3 spectratyping, we identified clonally expanded T cell receptor (TCR) β-chains in muscle sections of patients with inflammatory muscle diseases. By immunohistochemistry, we identified those Vβ-positive T cells that fulfilled the morphological criteria of myocytotoxicity and isolated them by laser microdissection. Next, we identified coexpressed pairs of TCR α- and β-chains by a multiplex PCR protocol, which allows the concomitant amplification of both chains from single cells. This concomitant amplification had not been achieved previously in histological sections, mainly because of the paucity of available anti-α-chain antibodies and the great heterogeneity of the α-chain genes. From muscle tissue of a patient with polymyositis, we isolated 64 T cells that expressed an expanded Vβ1 chain. In 23 of these cells, we identified the corresponding α-chain. Twenty of these 23 α-chains were identical, suggesting antigen-driven selection. After functional reconstitution of the αβ-pairs, their antigen-recognition properties could be studied. Our results open avenues for combined analysis of the full TCR α- and β-chain repertoire in human inflammatory tissues.

Background— Atrioventricular (AV) nodal ablation for management of atrial fibrillation (AF) is irreversible and requires permanent pacemaker implantation. We hypothesized that as an alternative, implantation of autologous fibroblasts in the perinodal region would focally modify AV nodal conduction and that this modulation would be enhanced by pretreatment with transforming growth factor-β1 (TGF-β1), a stimulant of fibroblasts. Methods and Results— Skin biopsies were taken from 12 mongrel dogs, and derived fibroblasts were dissociated and grown in culture for 2 weeks. Multiple injections (0.25 mL) were made through an 8F NOGA catheter along the fast/slow AV nodal pathways as guided by an electroanatomic mapping system. Seven dogs received fibroblasts alone (1×10 6 cells/mL), 7 dogs received TGF-β1 (5 μg), 4 dogs received fibroblasts and TGF-β1 (1×10 6 cells/mL+5 μg), and 4 dogs received saline only. AV node function was assessed at baseline and after 4 weeks. Saline (80 mL) with assigned therapy (0.25 mL per injection) was injected into the peri-AV nodal region in each dog. At baseline, the AH interval (66±3 ms) and the average RR interval (331±17 ms) in pacing-induced AF were similar in each cohort. The increase in AH interval in normal sinus rhythm was longer after fibroblast (23±4 versus 5±5 ms; P =0.05) and fibroblast plus TGF-β1 (50±5 versus 5±5 ms; P <0.001) injections than with saline alone, with similar findings during high right atrium and distal coronary sinus pacing. The AH interval was not significantly increased after TGF-β1 injections. The AH interval was significantly longer after fibroblast plus TGF-β1 injections than with either therapy (TGF-β1 or fibroblasts) alone. The RR interval during AF was increased in dogs that received fibroblasts alone (110±36 versus −41±34 ms) and to a greater extent with the addition of TGF-β1 (294±108 versus −41±34 ms). No AV block was seen in any cohort at 4 weeks. Labeled fibroblasts that expressed vimentin were identified in all dogs that received cell injections at 4 weeks. Conclusions— AV nodal modification can be achieved with injected fibroblasts without the creation of AV block. The effect on AV node conduction is substantially enhanced by pretreatment of fibroblasts with TGF-β1. These data have therapeutic potential for the management of rapid ventricular rate during AF without pacemaker implantation.

Abstract Purpose: In the adjuvant treatment of estrogen receptor (ER)–positive breast cancer, additional markers are needed to identify women at high risk for recurrence. Experimental Design: We examined the association between the ratio of the homeobox 13 (HOXB13) to interleukin-17B receptor (IL-17BR) expression and the clinical outcomes of relapse and survival in women with ER-positive breast cancer enrolled onto a North Central Cancer Treatment Group adjuvant tamoxifen trial (NCCTG 89-30-52). Results: Tumor blocks were obtained from 211 of 256 eligible patients, and quantitative reverse transcription-PCR profiles for HOXB13 and IL-17BR were obtained from 206 patients. The cut point for the two-gene log 2(expression ratio) that best discriminated clinical outcome (recurrence and survival) was selected and identified women with significantly worse relapse-free survival (RFS), disease-free survival (DFS), and overall survival (OS), independent of standard prognostic markers. The cut point differed as a function of nodal status [node negative (59th percentile) versus node positive (90th percentile)]. In the node-positive cohort (n = 86), the HOXB13/IL-17BR ratio was not associated with relapse or survival. In contrast, in the node-negative cohort (n = 130), a high HOXB13/IL-17BR ratio was associated with significantly worse RFS [hazard ratio (HR), 1.98; P = 0.031], DFS (HR, 2.03; P = 0.015), and OS (HR, 2.4; P = 0.014), independent of standard prognostic markers. Conclusion: A high HOXB13/IL-17BR expression ratio is associated with increased relapse and death in patients with resected node-negative, ER-positive breast cancer treated with tamoxifen and may identify patients in whom alternative therapies should be studied.

Abstract Bortezomib, a potent and reversible proteasome inhibitor, affects the myeloma cell and its microenvironment, resulting in down-regulation of growth and survival signaling pathways and durable responses in patients with relapsed and refractory myeloma. Potential associations between baseline parameters and outcomes with bortezomib were explored in 202 patients who received bortezomib 1.3 mg/m2 twice weekly for 2 weeks every 3 weeks for up to 8 cycles in a phase 2 trial. Using European Group for Blood and Marrow Transplantation criteria, the response rate (complete or partial response) to bortezomib alone was 27% and was not associated with sex, race, performance status, isotype, chromosome 13 deletion, number or type of previous therapies, or concentration of hemoglobin or β2-microglobulin. By multivariate analysis, factors associated with lower response were being age 65 or older versus younger than 65 (19% vs 32%; P &lt; .05) and plasma-cell infiltration in bone marrow greater than 50% versus 50% or less (20% vs 35%; P &lt; .05). Factors that may be indicative of tumor burden (bone marrow plasma-cell infiltration greater than 50%, hypoalbuminemia, thrombocytopenia) were predictive of overall survival. Chromosome 13 deletion and elevated β2-microglobulin, generally considered poor prognostic factors, were not predictive of poor outcome with bortezomib in this study.

Abstract The PAX8/PPARγ (PPFP) fusion-oncogene is moderately specific for follicular thyroid carcinomas (FTC). It remains unknown whether this can be translated into improved diagnosis, classification, or outcome prediction. We studied a cohort of well-characterized follicular adenomas (FA), FTC, and Hürthle cell carcinomas (HCC) from patients with complete clinical follow-up, to determine whether PPARγ immunohistochemistry (as a surrogate of PAX8/PPARγ expression) helps to distinguish FA from FTC and to assess its diagnostic accuracy as an adjunct to frozen section. We also correlated PPARγ staining with clinical outcomes to assess its role as a prognostic marker. PPARγ staining was more common in FTC (31 of 54; 57%) than in HCC (one of 23; 4%) or FA (four of 31; 13%) (P &lt; 0.000001). Adjunctive use of PPARγ immunohistochemistry improved diagnostic sensitivity of intraoperative frozen section from 84% to 96% (P &lt; 0.05) but reduced specificity from 100% to 90% (P &lt; 0.05). PPARγ staining was associated with favorable prognostic indicators (female gender, better tumor differentiation, and lesser risk of metastases). PPARγ staining may be helpful in the differential diagnosis of FA, FTC, and HCC, particularly when diagnostic sensitivity of histomorphology is reduced (e.g. during intraoperative frozen section). PPARγ staining also shows an association with favorable prognosis and may have a role in risk stratification.

AbstractAlthough hyperhomocysteinemia is an independent risk factor for cardiovascular disease, a direct role for homocysteine (Hcy) in this disease remains to be shown. Whereas diet-induced hyperhomocysteinemia promotes atherosclerosis in animal models, the effects of Hcy on atherogenesis in the absence of dietary perturbations is not known. We have generated double knock-out mice with targeted deletions of the genes for apolipoprotein E (apoE) and cystathionine β-synthase (CBS), which converts Hcy to cystathionine. ApoE−/−/CBS−/− mice developed aortic lesions even in the absence of dietary manipulation; lesion area and lesion cholesteryl ester (CE) and triglyceride (TG) contents increased with animal age and plasma Hcy levels. Plasma total cholesterol was significantly increased, whereas high density lipoprotein (HDL) cholesterol and TG concentrations of apoE−/−/CBS−/− mice were decreased. Cholesterol esterification and activities of enzymes catalyzing CE or TG formation in the vessel wall and in peritoneal macrophages were not changed by hyperhomocysteinemia. However, uptake of human acetyl-LDL, but not native low density lipoprotein (LDL), by mouse peritoneal macrophages was higher in the presence of hyperhomocysteinemia. These results suggest that isolated hyperhomocysteinemia is atherogenic and alters hepatic and macrophage lipoprotein metabolism, in part, by enhancing uptake of modified LDL.