Immunologic Resolution of Human Chronic Graft-versus-Host Disease

To determine the role of regulatory T lymphocytes (Tregs) in the pathogenesis of human chronic graft-versus-host disease (GVHD) and its clinical resolution, we evaluated long-term recipients of pediatric allogeneic hematopoietic stem cell transplantation (HSCT). Seventy-one recipients were evaluated, 30 of whom had a history of chronic GVHD, including 16 with active chronic GVHD and 14 with resolved chronic GVHD. There were no significant clinical differences and no differences in the frequency of Tregs (CD4⁺, CD127⁻, CD25⁺) between the recipients with active chronic GVHD and those with resolved chronic GVHD. Using the Miyara/Sakaguchi classification scheme to identify functional Tregs, a decreased frequency of functional resting Tregs (rTregs) was identified in recipients with active chronic GVHD (P = .009 compared with normal donors; P = .001 compared with HSCT recipients without history of chronic GVHD; P = .005 compared with recipients with resolved chronic GVHD). The frequency and number of recent thymic emigrants in rTregs were normal in recipients with resolved chronic GVHD, but persistently decreased in recipients with active chronic GVHD. These results support the hypothesis that the reestablishment of normal numbers of functional rTregs is required for the clinical resolution of chronic GVHD.     

Immunologic Analysis of HIV-Uninfected Taiwanese Children with BCG-Induced Disease

Objectives  The aim of this study was to evaluate immunity in HIV-uninfected children with bacille Calmette–Guerin-induced disease (BCG-ID) over an 8-year period, with particular emphasis on underlying diseases. Methods  Patient afflicted with BCG-ID proven by clinical courses, dermatologic features, pathology, specific polymerase chain reaction, and/or spoligotyping were enrolled between 2000 and 2007. Lymphocyte proliferation, polymorphonuclear function, interleukin (IL)-12/23–interferons (IFN)-γ circuit, and Toll-like receptor 2-associated signaling were investigated. Results  Of the 271,618 total live births who received the BCG vaccine, eight patients (seven males) with BCG-ID were enrolled during an 8-year period and presented as three disseminated, two distant, and three regional BCG-ID. Their age at onset ranged from 1 to 28 months. All had a vaccine-injection scar except for one with lower CD3 and natural killer cells, compatible with severe combined immunodeficiency (SCID) identified by IL-2 receptor common gamma chain (IL2RG) mutation (Arg226Lys). The other SCID patient with de novo IL2RG mutation (Trp74Gly) had more recurrent infections. The third patient with primary autoimmune neutropenia had disseminated BCG-ID extending to abdominal wall. The fourth patient with chronic mucocutaneous candidiasis had regional BCG-ID and impaired lymphocyte proliferation to Candida and BCG antigens. No defective evidence of polymorphonuclear functions, IL-12/23–IFN-γ circuit, and Toll-like receptor 2-associated signaling was detected in the remaining four patients. Conclusion  Immunologic analysis in HIV-uninfected patients with BCG-ID reveals primary immunodeficiency diseases, especially in those with deficiencies in T-cell and neutrophil functions observed in our cohort, including primary autoimmune neutropenia and chronic mucocutaneous candidiasis.     

Regulatory T Cells in Immunologic Self-Tolerance and Autoimmune Disease

Naturally arising CD25⁺CD4⁺ regulatory T cells play key roles in the maintenance of immunologic self-tolerance and negative control of various immune responses. The majority, if not all, of them are produced by the normal thymus as a functionally distinct T-cell subpopulation, and their generation is in part developmentally controlled. Genetic abnormality in the development and function of this population can indeed be a cause of autoimmune disease, immunopathology, and allergy in humans. This regulatory population can be exploited to prevent and treat autoimmune disease by strengthening and reestablishing immunologic self-tolerance.     

先天性心脏病的分子生物学研究

先天性心脏病的分子生物学研究谢进生（北京心肺血管疾病研究所－安贞医院心外科北京１０００２９）ＡｂｓｔｒａｃｔＦｏｒａｌｏｎｇｔｉｍｅ，ｉｔｈａｄｂｅｎｖｉｅｗｅｄｔｈａｔｍｏｓｔｃｏｎｇｅｎｉｔａｌｈｅａｒｔｄｉｓｅａｓｅｓ（ＣＨＤ）ａｒｅｃａｕｓｅ...     

Influenza and Bacterial Superinfection: Illuminating the Immunologic Mechanisms of Disease

Seasonal influenza virus infection presents a major strain on the health care system. Influenza virus infection has pandemic potential, which was repeatedly observed during the last century. Severe disease may occur in the young, in the elderly, in those with preexisting lung disease, and in previously healthy individuals. A common cause of severe influenza pathogenesis is superinfection with bacterial pathogens, namely, Staphylococcus aureus and Streptococcus pneumoniae. A great deal of recent research has focused on the immune pathways involved in influenza-induced susceptibility to secondary bacterial pneumonia. Both innate and adaptive antibacterial host defenses are impaired in the context of preceding influenza virus infection. The goal of this minireview is to highlight these findings and synthesize these data into a shared central theme of pathogenesis.     

Immunologic monitoring

Summary:  The development of reliable in vitro assays that could allow the quantitation and characterization of anti-donor alloimmune responses has always been a goal in clinical transplantation, both to predict presensitization to the transplanted tissue and to be able to identify rejection without resorting to more invasive tests. With recent development in our understanding of transplantation biology and therapeutics, there is a real expectation that these tests may be used to identify tolerance as much as to predict rejection. The traditional limiting dilution assays still have a contribution to make and are being complemented by an array of tools, such as ELISpot, flow cytometry-based techniques, and microarray analysis. The assays that have been informative, to date, are discussed in this review. This information will lead, at least, to a better understanding of how and when the rejection process occurs. More interestingly, the objective is to apply this information to evaluate tolerance-inducing strategies or to identify patients that have become tolerant to their graft and can be weaned of immunosuppression. Of course sensitive, accurate and specific immunologic monitoring has applications well beyond the field of transplantation.     

Cell Biology of Sarcomeric Protein Engineering: Disease Modeling and Therapeutic Potential

The cardiac sarcomere is the functional unit for myocyte contraction. Ordered arrays of sarcomeric proteins, held in stoichiometric balance with each other, respond to calcium to coordinate contraction and relaxation of the heart. Altered sarcomeric structure–function underlies the primary basis of disease in multiple acquired and inherited heart disease states. Hypertrophic and restrictive cardiomyopathies are caused by inherited mutations in sarcomeric genes and result in altered contractility. Ischemia‐mediated acidosis directly alters sarcomere function resulting in decreased contractility. In this review, we highlight the use of acute genetic engineering of adult cardiac myocytes through stoichiometric replacement of sarcomeric proteins in these disease states with particular focus on cardiac troponin I. Stoichiometric replacement of disease causing mutations has been instrumental in defining the molecular mechanisms of hypertrophic and restrictive cardiomyopathy in a cellular context. In addition, taking advantage of stoichiometric replacement through gene therapy is discussed, highlighting the ischemia‐resistant histidine‐button, A164H cTnI. Stoichiometric replacement of sarcomeric proteins offers a potential gene therapy avenue to replace mutant proteins, alter sarcomeric responses to pathophysiologic insults, or neutralize altered sarcomeric function in disease. Anat Rec, 297:1663–1669, 2014. © 2014 Wiley Periodicals, Inc.