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Background: Jehovah's Witnesses (JWs) refuse blood transfusions due to religious issues. This situation may impact kidney transplantation (KT) outcomes in case of hemorrhagic complications. We evaluated demographic characteristics of this population, hematologic safety, and graft outcomes., Methods: This was a retrospective, single-center study comparing KT outcomes in JW patients versus a non-JW control group. Hematologic endpoints included clinical indication for blood transfusion (hemoglobin <7 g/dL), decrease of hemoglobin >2 g/dL or hematocrit >5% in the first week after KT, hemorrhagic complications requiring surgery, and de novo prescription of erythropoiesis-stimulating agents. Secondary endpoints included delayed graft function, treated biopsy-proven acute rejection, renal function, mortality, and graft survival at 12 months., Results: From January 1989 to September 2018, we identified 143 JW (10 pediatric) and selected 142 matched control (non-JW) patients. There were no differences in the incidence of clinical indication for transfusion (13.3% versus 11.3%, P = 0.640), but a higher proportion of non-JW patients received transfusions (2.1% versus 9.2%, P = 0.010). There were no differences in the proportion of patients with decreased hemoglobin concentration, in reinterventions due to hemorrhagic complications, in the use of erythropoiesis-stimulating agents at hospital discharge, in the incidence of acute rejection, in renal function, and in mortality or graft survival rate at 12 months., Conclusions: In summary, this matched control cohort study suggests that, when clinically indicated, blood transfusions can be safely avoided in the majority of JW kidney transplant, who achieve and maintain comparable hemoglobin concentrations during the first year after transplantation compared with non-JW patients., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Autocrine activation of the complement receptors C3aR and CD46 by complement activation components C3a and C3b produced through C3 cleavage by the protease cathepsin L (CTSL) during T cell stimulation is a requirement for IFN-γ production and Th1 induction in human CD4 + T cells. Thus, lack of autocrine CD46 activation, such as in CD46-deficient patients, is associated with defective Th1 responses and recurrent infections. We have identified LGMN [the gene coding for legumain, also known as asparaginyl endopeptidase (AEP)] as one of the key genes induced by CD46 co-stimulation during human CD4 + T cell activation. AEP processes and activates a range of proteins, among those α1-thymosin and CTSL, which both drive intrinsically Th1 activity-but has so far not been described to be functionally active in human T cells. Here we found that pharmacological inhibition of AEP during activation of human CD4 + T cells reduced CTSL activation and the CTSL-mediated generation of intracellular C3a. This translated into a specific reduction of IFN-γ production without affecting cell proliferation or survival. In line with these findings, CD4 + T cells isolated from Lgmn -/- mice also displayed a specific defect in IFN-γ secretion and Th1 induction. Furthermore, we did not observe a role for AEP-driven autocrine α1-thymosin activation in T cell-derived IFN-γ production. These data suggest that AEP is an "upstream" activator of the CTSL-C3-IFN-γ axis in human CD4 + T cells and hence an important supporter of human Th1 induction.

Unlabelled: Defective immune regulation plays a permissive role enabling effector cells to initiate and perpetuate tissue damage, eventually resulting in autoimmune disease. Numerical and functional regulatory T-cell (Treg) impairment has been previously reported in autoimmune liver disease (AILD; including autoimmune hepatitis and autoimmune sclerosing cholangitis ASC). However, in these early reports, Tregs were phenotypically defined as CD4(+) CD25(+) or CD4(+) CD25(high) cells. In the current study, we reexamined phenotypic and functional properties of Tregs by adopting a more refined definition of these cells that also includes negativity or low level of expression of CD127. We studied 43 AILD patients and 22 healthy subjects (HSs) and found that CD4(+) CD25(+) CD127(-) Tregs were decreased in the former. This decrease was more marked in patients with active disease than in those in remission. In AILD, Treg frequencies correlated inversely with parameters of disease activity and were not affected by immunosuppressive treatment. We also document, for the first time, that, in AILD, bona-fide Tregs produce less interleukin (IL)-10 and are impaired in their ability to suppress CD4(+) CD25(-) target cell proliferation, a feature that in HSs, but not in AILDs, is dependent, at least in part, on IL-10 secretion. Decreased IL-10 production by Tregs in AILD is linked to poor responsiveness to IL-2 and phospho signal transducer and activator of transcription 5 up-regulation., Conclusion: Tregs are numerically impaired in AILD, this impairment being more prominent during active disease. Notably, defective IL-10 production, resulting from low Treg responsiveness to IL-2, contributes to Treg functional impairment., (© 2015 by the American Association for the Study of Liver Diseases.)

Unlabelled: Autoimmune hepatitis (AIH) is an important cause of severe liver disease and is associated with both quantitative and qualitative regulatory T-cell (Treg) impairments. Tregs express CD39, an ectonucleotidase responsible for extracellular nucleotide hydrolysis, culminating in the production of immunosuppressive adenosine. Here, we describe multiple CD39(pos) Treg defects that potentially contribute to the impaired immunoregulation that is characteristic of AIH. We have examined the frequency and phenotype of CD39(pos) Tregs by flow cytometry and measured their ectonucleotidase activity. The capacity of CD4(pos) CD25(high) , CD4(pos) CD25(high) CD39(pos) , and CD4(pos) CD25(high) CD39(neg) subsets to suppress both proliferation of effector T cells and interleukin (IL)-17 production was evaluated. In AIH, CD39(pos) Tregs are decreased in frequency, exhibit limited adenosine triphosphate/adenosine diphosphate hydrolysis activity, and fail to suppress IL-17 production by effector CD4 T cells. Moreover, these CD39(pos) Tregs display a more proinflammatory profile in AIH, which is characterized by elevated CD127 positivity, and a greater propensity to produce interferon-gamma or IL-17 upon challenge with proinflammatory stimuli., Conclusions: In AIH, CD39(pos) Tregs are decreased in number, fail to adequately hydrolyze proinflammatory nucleotides and do not efficiently suppress IL-17 production by effector CD4 T cells. CD39(pos) Tregs show plasticity and are unstable upon proinflammatory challenge, suggesting that defective immunoregulation in AIH might result not only from reduced Treg number and function, but also from increased conversion of Tregs into effector cells., (© 2014 by the American Association for the Study of Liver Diseases.)

The intestinal epithelium not only provides a vital physical barrier between the host and environment but is also required for uptake of nutrients and the induction of tolerance against commensals. Deregulation of any of these functions leads to several disease states including chronic infection, inflammatory bowel disease, and cancer. Here, we describe a novel role for the complement regulator CD46 in the regulation of intestinal epithelial cell (IEC) barrier function. We found that CD46 directly interacts in IECs with the cytoplasmic kinase SPAK and with transmembrane E-cadherin, both proteins necessary for epithelial cell junction and barrier formation. Further, CD46 activation on Caco-2 cells induced rapid and significant decrease in transepithelial resistance with concomitant increase in paracellular permeability. Importantly, though CD46 activation of IEC layers allowed for increased transgression of pathogenic E. coli, it also increased epithelial cell proliferation and accelerated wound repair. These data suggest a previously unappreciated role for CD46 in the maintenance of epithelial cell barrier integrity as well as barrier repair. However, this role for CD46 as "gate keeper" of the epithelium could also provide reason as to why so many pathogens bind to CD46 as such event would facilitate infection.

Control of IFN-γ-secreting T helper (Th) 1 cells prevents autoimmunity and immunopathology during infection. IL-10-mediated suppression of Th1 cells is achieved not only through IL-10 produced extrinsically, but also through a negative feedback loop that induces "intrinsic" IL-10 expression in cells also expressing IFN-γ, during Th1 lineage differentiation. Targeting this Th1 cell IFN-γ to IL-10 switching is a tantalising prospect for developing therapeutics for Th1-mediated diseases. In this review, the molecular pathways that regulate IFN-γ versus IL-10 expression in Th1 cells are examined, with focus on the role of complement regulator and T cell co-stimulatory molecule CD46, and also discussed are challenges and controversies in the field., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

In this study we demonstrate a new form of immunoregulation: engagement on CD4(+) T cells of the complement regulator CD46 promoted the effector potential of T helper type 1 cells (T(H)1 cells), but as interleukin 2 (IL-2) accumulated, it switched cells toward a regulatory phenotype, attenuating IL-2 production via the transcriptional regulator ICER/CREM and upregulating IL-10 after interaction of the CD46 tail with the serine-threonine kinase SPAK. Activated CD4(+) T cells produced CD46 ligands, and blocking CD46 inhibited IL-10 production. Furthermore, CD4(+) T cells in rheumatoid arthritis failed to switch, consequently producing excessive interferon-gamma (IFN-gamma). Finally, gammadelta T cells, which rarely produce IL-10, expressed an alternative CD46 isoform and were unable to switch. Nonetheless, coengagement of T cell antigen receptor (TCR) gammadelta and CD46 suppressed effector cytokine production, establishing that CD46 uses distinct mechanisms to regulate different T cell subsets during an immune response.

In the last years small RNA molecules, i.e. microRNA (miRNA) encoded by miR genes, have been found to play a crucial role in regulating gene expression of a considerable part of plant's and animal's genome. Here, we report the essential information on biogenesis of miRNAs and recent evidence on their important role in human diseases. Emphasis has been given to miR-155, since this molecule represents a typical multifunctional miRNA. Recent data indicate that miR-155 has distinct expression profiles and plays a crucial role in various physiological and pathological processes such as haematopoietic lineage differentiation, immunity, inflammation, cancer, and cardiovascular diseases. Moreover, miR-155 has been found to be implicated in viral infections, particularly in those caused by DNA viruses. The available experimental evidence indicating that miR-155 is over expressed in a variety of malignant tumors allows us to include this miRNA in the list of genes of paramount importance in cancer diagnosis and prognosis. Exogenous molecular control in vivo of miR-155 expression could open up new ways to restrain malignant growth and viral infections, or to attenuate the progression of cardiovascular diseases.

Aim: To investigate the function of NOD2 in colonic epithelial cells (CEC)., Methods: A combination of in vivo and in vitro analyses of epithelial cell turnover in the presence and absence of a functional NOD2 protein and, in response to enteric Salmonella typhimurium infection, were used. shRNA interference was also used to investigate the consequences of knocking down NOD2 gene expression on the growth and survival of colorectal carcinoma cell lines., Results: In the colonic mucosa the highest levels of NOD2 expression were in proliferating crypt epithelial cells. Muramyl dipeptide (MDP), that is recognized by NOD2, promoted CEC growth in vitro. By contrast, the growth of NOD2-deficient CECs was impaired. In vivo CEC proliferation was also reduced and apoptosis increased in Nod2(-/-) mice, which were also evident following enteric Salmonella infection. Furthermore, neutralization of NOD2 mRNA expression in human colonic carcinoma cells by shRNA interference resulted in decreased survival due to increased levels of apoptosis., Conclusion: These findings are consistent with the involvement of NOD2 protein in promoting CEC growth and survival. Defects in proliferation by CECs in cases of CD may contribute to the underlying pathology of disrupted intestinal homeostasis and excessive inflammation.

DNA damage activates several mechanisms such as DNA repair and cell cycle checkpoints. The Saccharomyces cerevisiae heterotrimeric checkpoint clamp consisting of the Rad17, Mec3 and Ddc1 subunits is an early response factor to DNA damage and activates checkpoints. This complex is structurally similar to the proliferating cell nuclear antigen (PCNA), which serves as a sliding clamp platform for DNA replication. Growing evidence suggests that PCNA-like complexes play a major role in DNA repair as they have been shown to interact with and stimulate several proteins, including specialized DNA polymerases. With the aim of extending our knowledge concerning the link between checkpoint activation and DNA repair, we tested the possibility of a functional interaction between the Rad17/Mec3/Ddc1 complex and the replicative DNA polymerases alpha, delta and epsilon. The analysis of sensitivity response of single and double mutants to UVC and 8-MOP + UVA-induced DNA damage suggests that the PCNA-like component Mec3p of S. cerevisiae neither relies on nor competes with the third subunit of DNA polymerase delta, Pol32p, for lesion removal. No enhanced sensitivity was observed when inactivating components of DNA polymerases alpha and epsilon in the absence of Mec3p. The hypersensitivity of pol32Delta to photoactivated 8-MOP suggests that the replicative DNA polymerase delta also participates in the repair of mono- and bi-functional DNA adducts. Repair of UVC and 8-MOP + UVA-induced DNA damage via polymerase delta thus occurs independent of the Rad17/Mec3/Ddc1 checkpoint clamp.

Complementation analysis of the pso9-1 yeast mutant strain sensitive to photoactivated mono- and bifunctional psoralens, UV-light 254 nm, and nitrosoguanidine, with pso1 to pso8 mutants, confirmed that it contains a novel pso mutation. Molecular cloning via the reverse genetics complementation approach using a yeast genomic library suggested pso9-1 to be a mutant allele of the DNA damage checkpoint control gene MEC3. Non-complementation of several sensitivity phenotypes in pso9-1/mec3Delta diploids confirmed allelism. The pso9-1 mutant allele contains a -1 frameshift mutation (deletion of one A) at nucleotide position 802 (802delA), resulting in nine different amino acid residues from that point and a premature termination. This mutation affected the binding properties of Pso9-1p, abolishing its interactions with both Rad17p and Ddc1p. Further interaction assays employing mec3 constructions lacking the last 25 and 75 amino acid carboxyl termini were also not able to maintain stable interactions. Moreover, the pso9-1 mutant strain could no longer sense DNA damage since it continued in the cell cycle after 8-MOP + UVA treatment. Taken together, these observations allowed us to propose a model for checkpoint activation generated by photo-induced adducts.

Originally used in warfare, air guns are commonly used in target shooting, as toys, and as "beginner" guns for children. The projectile force of these weapons can rival that of many conventional handguns. Pneumatic weapons pose a serious threat to the pediatric population, and their potential for serious injury must be recognized.

Cutis laxa acquisita is a rare disorder that affects collagen and elastin metabolism. The cause is unknown. Characteristic features include sagging and laxity of the skin, as well as involvement of the lungs, heart, gastrointestinal system, and urogenital tract. Three cases of cutis laxa acquisita have been reported in association with multiple myeloma. Due to the rarity of these disorders, a linkage has been postulated. The clinical and histologic data from the fourth case of cutis laxa acquisita associated with multiple myeloma were compared to the three other cases previously reported in the literature. The relationship between acquired cutis laxa and multiple myeloma is unclear, with only one case revealing possible immune-mediated elastin destruction via IgG immunoglobulin bound to dermal elastin fibers on immunofluoresence examination. No pattern in the clinical courses of the disorder can be seen on review of the four cases with coincident disease. We hypothesize that cutis laxa acquisita represents a paraneoplastic process of multiple myeloma, given the rarity of these diseases. Further investigation is necessary to determine the underlying linkage between these disorders. We suggest that serum and urine protein electrophoresis results be obtained in patients presenting with cutis laxa acquisita to screen for multiple myeloma given this association.

Background: The benefits of elective lymph node dissection (ELND) in the treatment of melanoma remain controversial, however, it may be beneficial in some patients. Tattoo pigment from decorative tattoos may migrate to the regional lymph nodes. In patients who develop malignant melanoma and who have been tattooed, this pigment may clinically mimic metastatic disease., Objective: We wish to alert clinicians that pigment from tattoos may migrate to the regional lymph nodes. In the unusual instance of a tattooed patient who develops malignant melanoma, when undergoing ELND, surgeons should rely on histologic confirmation of metastatic disease before altering operative plans., Methods: ELND for malignant melanoma, in a patient with a history of decorative tattoos that had been removed by dermabrasion, was performed. Black lymph nodes that clinically resembled metastatic disease were identified. Subsequent histologic examination revealed normal lymph node architecture with a heavy collection of black pigment. Mass spectrophotometry showed this pigment to be consistent with tattoo dye., Results: A patient who had undergone dermabrasion for removal of decorative tattoos developed malignant melanoma in the same extremity. Clinically suspicious black lymph nodes were identified during ELND. Histologic examination did not reveal metastatic disease. Additional therapy was not considered intra- or postoperatively even though the clinical suspicion of metastatic disease was high. The patient was not subjected to any unnecessary emotional or physical distress pending histologic confirmation., Conclusions: Tattoo pigment in the lymph nodes may clinically mimic metastatic melanoma. Histologic confirmation of metastatic disease should always be obtained before additional therapy is considered.

A "great imitator," like the perhaps more familiar syphilis and tuberculosis, coccidioidomycosis has a wide variety of clinical presentations. A recent dramatic surge in the incidence of this saprobe increases the likelihood that clinicians will encounter an infected patient. Although rare, the disseminated form of the disease is potentially fatal. Vigilance and familiarity with the many faces of this pathogen will permit early detection and treatment. We present two cases of disseminated coccidioidomycosis and briefly review this increasingly common fungal infection.

Thrombosis of intravascular catheters is a well-recognized and potentially serious complication, which has been treated successfully with thrombolytic agents. A routine echocardiogram in a patient with a temporary transvenous pacemaker demonstrated a large thrombus attached to the pacing electrode. This was dissolved successfully and uneventfully with high-dose intravenous streptokinase therapy. To our knowledge, this is the first report of the successful lysis of a right atrial thrombus complicating a temporary transvenous pacemaker.