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Blood-borne RNA circulating in association with autoantibodies is a potent stimulator of interferon production and immune system activation. RSLV-132 is a novel fully human biologic Fc fusion protein that is comprised of human RNase fused to the Fc domain of human IgG1. The drug is designed to remain in circulation and digest extracellular RNA with the aim of preventing activation of the immune system via Toll-like receptors and the interferon pathway. The present study describes the first clinical study of nuclease therapy in 32 subjects with systemic lupus erythematosus. The drug was well tolerated with a very favorable safety profile. The approximately 19-day serum half-life potentially supports once monthly dosing. There were no subjects in the study that developed anti-RSLV-132 antibodies. Decreases in B-cell activating factor correlated with decreases in disease activity in a subset of patients. [ABSTRACT FROM AUTHOR]

Background: Since bleeding is a major cause of early mortality in trauma, there is continued interest in providing transfusion support as early as possible to trauma patients. Various approaches have been taken to accomplish this, including the rapid provision of blood products upon arrival at the hospital, as well as a variety of prehospital approaches. However, implementing prehospital blood availability statewide for use in all populations has been limited., Study Design and Methods: The program described for prehospital transfusion identifies a direct partnership between state EMS providers and the local blood center. Predictive modeling is compared to early outcome data of the first 100 patients who received whole blood from this program. Additional discussion contains key elements of the program, including planning, validation, and implementation., Results: Between May 2023 and July 2024, an average of 11 prehospital whole blood units were transfused per month against the projected average of 10-16 units administered per month, with the median time to transfusion of 29.2 min. The leading reason for blood administration was due to blunt trauma. Of the patients who were not in prehospital cardiac arrest prior to paramedic arrival or excluded for other reasons, approximately 95% survived to hospital discharge., Discussion: Implementation of prehospital whole blood across the state has demonstrated effectiveness early within the first year of the program. Continued process improvements will be implemented with statewide ground paramedic agency utilization of whole blood as well as expansion into aviation divisions for more expedient whole blood administration times., (© 2025 AABB.)

Frequently overlooked, Morel-Lavallée lesions are associated with a closed degloving or shearing mechanism causing a dehiscence of underlying soft tissue with formation of a potential space. This space fills with blood, lymph, and cellular debris, giving the lesion a fluctuant appearance on examination. The potential space associated with larger lesions can be a source for hemorrhage in the appropriate clinical context. However, these lesions are often diagnosed late in their clinical course or are misdiagnosed, leading to long-term complications. Management of this injury typically depends upon the size of the lesion. This article discusses a Morel-Lavallée lesion in an active-duty Servicemember requiring treatment by a plastic surgeon and includes the pathophysiology of Morel-Lavallée lesions, diagnostic strategies, and management pearls., (2016.)

Radial glia serve as the resident neural stem cells in the embryonic vertebrate nervous system, and their proliferation must be tightly regulated to generate the correct number of neuronal and glial cell progeny in the neural tube. During a forward genetic screen, we recently identified a zebrafish mutant in the kif11 loci that displayed a significant increase in radial glial cell bodies at the ventricular zone of the spinal cord. Kif11, also known as Eg5, is a kinesin-related, plus-end directed motor protein responsible for stabilizing and separating the bipolar mitotic spindle. We show here that Gfap+ radial glial cells express kif11 in the ventricular zone and floor plate. Loss of Kif11 by mutation or pharmacological inhibition with S-trityl-L-cysteine (STLC) results in monoastral spindle formation in radial glial cells, which is characteristic of mitotic arrest. We show that M-phase radial glia accumulate over time at the ventricular zone in kif11 mutants and STLC treated embryos. Mathematical modeling of the radial glial accumulation in kif11 mutants not only confirmed an ~226× delay in mitotic exit (likely a mitotic arrest), but also predicted two modes of increased cell death. These modeling predictions were supported by an increase in the apoptosis marker, anti-activated Caspase-3, which was also found to be inversely proportional to a decrease in cell proliferation. In addition, treatment with STLC at different stages of neural development uncovered two critical periods that most significantly require Kif11 function for stem cell progression through mitosis. We also show that loss of Kif11 function causes specific reductions in oligodendroglia and secondary interneurons and motorneurons, suggesting these later born populations require proper radial glia division. Despite these alterations to cell cycle dynamics, survival, and neurogenesis, we document unchanged cell densities within the neural tube in kif11 mutants, suggesting that a mechanism of compensatory regulation may exist to maintain overall proportions in the neural tube. We propose a model in which Kif11 normally functions during mitotic spindle formation to facilitate the progression of radial glia through mitosis, which leads to the maturation of progeny into specific secondary neuronal and glial lineages in the developing neural tube., (Copyright © 2014. Published by Elsevier Inc.)

The majority of those infected with HIV in sub-Saharan Africa do not have access to antiretroviral therapy, which is known to prolong the lives of HIV-positive persons in industrialized countries. Although the availability of antiretroviral therapy for those infected with HIV has increased worldwide, the infection rate out surpasses those started on such treatment. Without an AIDS vaccine or curative treatment, and given the difficulty in getting persons at risk to adopt healthy sexual behaviors, alternative approaches to decrease the spread of HIV infection are urgently needed. Three recent randomized controlled trials undertaken in Kisumu, Kenya, Raki District, Uganda and Orange Farm, South Africa have confirmed that male circumcision reduces the risk of heterosexually acquired HIV infection in men by approximately 51% to 60%. These three studies provide a solid evidence-base for future health policy. The procedure for adolescents and adults is expensive compared to abstinence, condoms or other methods; and the surgery is not without serious risks if performed by traditional healers using unsterilized blades as often happens in rural Africa. However, neonatally, the procedure is relatively inexpensive and the risks diminish considerably. Mandating neonatal male circumcision is an effective therapy that has minimal risks, is cost efficient and will save human lives. To deny individuals access to this effective therapy is to deny them the dignity and respect all persons deserve. Neonatal male circumcision is medically necessary and ethically imperative.

Inexpensive methods were developed for isolating and isotopically labeling tryptic peptides that contain either cysteine or methionine. After covalently capturing cysteine-containing peptides with pyridyl disulfide reactive groups on agarose beads, extensive wash steps were applied, and the attached peptides were released using a reducing agent. This approach results in less nonspecifically bound peptides and eliminates the possibility of generating avidin peptide background ions that can arise when using methods based on biotin and avidin (e.g. isotope-coded affinity tag). The thiols were alkylated using either N-ethyl- or N-D5-ethyl-iodoacetamide, both of which can be synthesized in a single step using inexpensive reagents. This isotopic labeling does not greatly increase the peptide mass, nor does it affect the peptide ion charge state in electrospray ionization. In addition, methionine-containing peptides were captured using commercially available methionine-reactive beads, and relative quantitation of peptides was achieved by isotopic labeling of amino groups using activated esters of either nicotinic acid or D4-nicotinic acid. These methods were used to study the metalloprotease-mediated shedding of cell surface proteins from a mouse monocyte cell line that had been treated with a phorbol ester and lipopolysaccharide. In addition to the identification of proteins previously determined to be inducibly shed, three new shed proteins were identified: CD18, ICOS ligand, and tumor endothelial marker 7-related protein.

Tumour necrosis factor alpha (TNF alpha)-converting enzyme (TACE/ADAM-17, where ADAM stands for a disintegrin and metalloproteinase) releases from the cell surface the extracellular domains of TNF and several other proteins. Previous studies have found that, while purified TACE preferentially cleaves peptides representing the processing sites in TNF and transforming growth factor alpha, the cellular enzyme nonetheless also sheds proteins with divergent cleavage sites very efficiently. More recent work, identifying the cleavage site in the p75 TNF receptor, quantifying the susceptibility of additional peptides to cleavage by TACE and identifying additional protein substrates, underlines the complexity of TACE-substrate interactions. In addition to substrate specificity, the mechanism underlying the increased rate of shedding caused by agents that activate cells remains poorly understood. Recent work in this area, utilizing a peptide substrate as a probe for cellular TACE activity, indicates that the intrinsic activity of the enzyme is somehow increased.

Interleukin (IL-) 2 and IL-15 share the IL-2 receptor betagamma c subunits (IL-2Rbetagamma c) but have specific, unique alpha receptor subunits. We studied species specificity of human (hu), simian (si), and mouse (mu) IL-15 and found that hu and si IL-15 behaved similarly in all systems investigated. Hu and mu IL-15 bound hu or mu IL-15Ralpha with equal high affinity in the presence or absence of IL-2Rbetagamma c and exhibited similar proliferative activities on cells containing all three subunits. However, quantitative differences were noted in the specific activity of hu and mu IL-15 in both in vitro and in vivo systems utilizing IL-2Rbetagamma c in the absence of IL-15Ralpha. These data show that hu IL-15 may be used in mouse model systems, however care must be taken when comparing the efficacy and toxicity of cytokines across species.

Interleukin 15 (IL-15) is a member of the four-helix bundle cytokine family that shares many in vitro biological activities with IL-2. Previous work demonstrated that IL-15 utilizes the beta and gamma chains of the IL-2 receptor (IL-2R), and that these are essential for IL-15-mediated signal transduction. However, several lines of evidence indicated the existence of an additional, IL-15-specific receptor component. An IL-15 binding chain was identified on a murine T cell clone, and direct expression cloning was used to isolate the corresponding cDNA. The predicted structure of this protein shows sequence similarity to the IL-2R alpha chain. Transfection of this cDNA into a murine, IL-3-dependent myeloid cell line, 32D-01, conferred IL-15 binding and, together with transfection of the IL-2R beta chain, rendered the cells responsive to IL-15 stimulation. This experiment confirmed that the IL-15 binding chain is part of the IL-15 receptor, and it is designated as the IL-15R alpha subunit. The expression pattern of the IL-15R alpha mRNA is distinct from that of IL-2R alpha mRNA. Recombinant expression of a soluble form of IL-15R alpha demonstrated that it is a potent inhibitor of IL-15 biological activity.

A cytokine was identified that stimulated the proliferation of T lymphocytes, and a complementary DNA clone encoding this new T cell growth factor was isolated. The cytokine, designated interleukin-15 (IL-15), is produced by a wide variety of cells and tissues and shares many biological properties with IL-2. Monoclonal antibodies to the beta chain of the IL-2 receptor inhibited the biological activity of IL-15, and IL-15 competed for binding with IL-2, indicating that IL-15 uses components of the IL-2 receptor.

The ability of murine Steel factor to promote the in vitro production of granulocyte-macrophage progenitor cells (CFU-GM) was examined in short-term liquid cultures. Bone marrow from C57BL/6J or Sl/Sld mice was placed in culture for seven days with either Steel factor alone or in the presence of IL-3. CFU-GM responsive to GM-CSF, IL-3, and CSF-1 were measured in the input population and again after 3 or 7 days in culture. Steel factor alone increased the number of all CFU-GM types as early as 3 days after culture initiation, with further increases at day 7. This effect was potentiated by the addition of IL-3. Production of CFU-GM by C57BL/6J or Sl/Sld marrow was comparable except for enhanced production of CSF-1 responsive progenitors by Sl/Sld marrow. A recombinant Sld protein was also shown to be equivalent to the wild-type protein in its capacity to promote CFU-GM production from normal bone marrow.

The gene product of the murine Steel (Sl) locus encodes an early-acting hematopoietic growth factor that is a ligand for the c-kit protooncogene. Several cDNAs for the Sl gene product, known as mast cell growth factor (MGF), stem cell factor (SCF), or kit ligand (KL), have recently been isolated, and both soluble and membrane-associated versions have been shown to be biologically active. The potential for therapeutic usage of recombinant MGF (rMGF) indicated a need for determining the biodistribution and elimination parameters of this cytokine. Pharmacokinetic studies demonstrated that radiolabeled rMGF had a distribution half-life of 2 min and an elimination half-life of 2.1 h in wild-type mice following iv injection, during which a striking localization of labeled rMGF in the lungs was noted. When administered by subcutaneous injection the elimination half-life was prolonged to 8.4 h. The primary sites of rMGF elimination appeared to be the kidneys and the liver. Pharmacokinetic analysis of labeled rMGF in mutant Sl/Sld mice, which are mast cell deficient, demonstrated similar distribution and elimination half-lives compared to wild-type mice (1.4 min and 1.8 h, respectively). In addition, the biodistribution pattern of the labeled rMGF in Sl/Sld mice was similar to that observed in wild-type mice, including the striking localization to the lungs. Binding of radiolabeled rMGF to lungs in vivo subsequent to iv injection was completely inhibited by excess unlabeled rMGF. Interestingly, mice that received an iv injection of the higher doses of rMGF (15 micrograms) demonstrated profound respiratory distress and hypotension within minutes of administration. Histologic analysis of lungs from such mice revealed extensive mast cell degranulation, which was associated with vasodilatation and pronounced hyperemia of virtually all pulmonary vessels. The respiratory distress in normal mice was probably a consequence of mast cell degranulation induced by rMGF since similar findings were not observed in Sl/Sld mice injected with identical concentrations of rMGF.

Human mast cell growth factor (MGF) complementary DNAs (cDNAs) were cloned from HeLa cells using the polymerase chain reaction with oligonucleotides corresponding to murine and human MGF sequences. Sequencing of the cloned human MGF polymerase chain reaction products revealed two types of cDNA: a full length form corresponding in size to the murine cDNA, and an alternately spliced clone with a deletion of the sixth exon of the gene. Since membrane-bound MGF is predicted to be proteolytically cleaved within the sequences encoded by exon 6 to generate a soluble protein, this alternately spliced cDNA would likely encode a noncleavable, membrane-bound form of MGF. No difference in biological activity on human bone marrow cells was observed with recombinant, soluble forms of both types of human MGF protein. Our previous localization of the murine MGF gene to the Sl locus on chromosome 10 suggested (via conserved linkage groups) that the human MGF gene would be located on human chromosome 12. Therefore, rodent-human somatic cell hybrids with or without an entire human chromosome 12 and hybrids retaining partial 12 were tested by Southern blot analysis and used to show the presence of the human Mgf locus at chromosome region 12q. Chromosomal in situ hybridization localized the gene to 12q22-q24 in the region predicted by the comparative mapping of the murine Mgf/Sl locus.