Broadly neutralizing antibodies (bNAbs), which develop over time in some HIV-1 infected individuals, define critical epitopes for HIV vaccine design. Using a systematic approach, we have examined neutralization breadth in the sera of about 1,800 HIV-1 infected individuals, primarily infected with non-clade B viruses, and selected donors for monoclonal antibody (mAb) generation. We then used a high-throughput neutralization screen of antibody-containing culture supernatants from approximately 30,000 activated memory B cells from a clade A-infected African donor to isolate two potent mAbs that target a broadly neutralizing epitope. The previously undescribed epitope is preferentially expressed on trimeric Envelope protein and spans conserved regions of variable loops of the gp120 subunit. The results provide a framework for the design of new vaccine candidates for the elicitation of bNAb responses.

Broadly neutralizing antibodies (bnAbs) against highly variable viral pathogens are much sought-after to treat or protect against global circulating viruses. We have probed the neutralizing antibody repertoires of four HIV-infected donors with remarkably broad and potent neutralizing responses and rescued 17 new monoclonal antibodies (MAbs) that neutralize broadly across clades. Many of the new MAbs are almost 10-fold more potent than the recently described PG9, PG16, and VRC01 bnMAbs and 100-fold more potent than the original prototype HIV bnMAbs1–3. The MAbs largely recapitulate the neutralization breadth found in the corresponding donor serum and many recognize novel epitopes on envelope (Env) glycoprotein gp120, illuminating new targets for vaccine design. Analysis of neutralization by the full complement of anti-HIV bnMAbs now available reveals that certain combinations of antibodies provide significantly more favorable coverage of the enormous diversity of global circulating viruses than others and these combinations might be sought in active or passive immunization regimes. Overall, the isolation of multiple HIV bnMAbs, from several donors, that, in aggregate, provide broad coverage at low concentrations is a highly positive indicator for the eventual design of an effective antibody-based HIV vaccine.

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Gene expression patterns can provide vital clues to the pathogenesis of neoplastic diseases. We investigated the expression of 950 genes in Hodgkin's disease (HD) by analyzing differential mRNA expression using microarrays. In two independent microarray experiments, the HD-derived cell lines L428 and KMH2 were compared with an Epstein-Barr virus (EBV)-immortalized lymphoblastoid B cell line, LCL-GK. Interleukin (IL)-13 and IL-5 were found to be highly expressed in the HD-derived cell lines. Examination of IL-13 and IL-5 expression by Northern blot analysis and enzyme-linked immunosorbent assay confirmed these results and revealed the expression of IL-13 in a third HD-derived cell line, HDLM2. Control LCL and EBV-negative non-Hodgkin lymphoma–derived cell lines did not express IL-13. In situ hybridization of lymph node tissue from HD patients showed that elevated levels of IL-13 were specifically expressed by Hodgkin/Reed-Sternberg (H/RS) tumor cells. Treatment of a HD-derived cell line with a neutralizing antibody to IL-13 resulted in a dose-dependent inhibition of H/RS cell proliferation. These data suggest that H/RS cells produce IL-13 and that IL-13 plays an important role in the stimulation of H/RS cell growth, possibly by an autocrine mechanism. Modulation of the IL-13 signaling pathway may be a logical objective for future therapeutic strategies.

Atopic dermatitis (AD) is a chronic, systemic, inflammatory disease that affects the skin and is characterized by persistent itch and marked redness. AD is associated with an increased risk of skin infections and a reduced quality of life. Most AD treatment options to date were not designed to selectively target disease‐causing pathways that have been established for this indication. Topical therapies have limited efficacy in moderate‐to‐severe disease, and systemic agents such as corticosteroids and immunosuppressants present with tolerability issues. Advances in the understanding of AD pathobiology have made possible a new generation of more disease‐specific AD therapies. AD is characterized by the inappropriate activation of type 2 T helper (Th2) cells and type 2 innate lymphoid (ILC2) cells, with a predominant increase in type 2 cytokines in the skin, including interleukin (IL)‐13 and IL‐4. Both cytokines are implicated in tissue inflammation and epidermal barrier dysfunction, and monoclonal antibodies targeting each of these interleukins or their receptors are in clinical development in AD. In March 2017, dupilumab, a human anti–IL‐4Rα antibody, became the first biologic to receive approval in the United States for the treatment of moderate‐to‐severe AD. The anti–IL‐13 monoclonal antibodies lebrikizumab and tralokinumab, which bind different IL‐13 epitopes with potentially different effects, are currently in advanced‐stage trials. Here, we briefly review the underlying pathobiology of AD, the scientific basis for current AD targets, and summarize current clinical studies of these agents, including new research to develop both predictive and response biomarkers to further advance AD therapy in the era of precision medicine.

Using DNA encoding the largest subunit of Drosophila melanogaster RNA polymerase II, we isolated the homologous hamster RP021 gene. Nucleotide sequencing of both the hamster and D. melanogaster RP021 DNAs confirmed that the RP021 polypeptides of these two species, like the Saccharomyces cerevisiae RP021 polypeptide, contain both an N-terminal region homologous to the Escherichia coli RNA Biochemical and genetic approaches are being used to study the molecular mechanisms which regulate mRNA transcription in eucaryotes. Through such approaches, regulatory cis-acting DNA elements have been identified and protein factors that recognize these specific sequences have been described. These DNA-binding transcription factors must directly or indirectly affect the activity of RNA polymerase II. To address this aspect of transcriptional regulation, a more thorough understanding of this enzyme itself may be required. Toward this end, we and others have used mutations that increase the a-amanitin resistance of RNA polymerase II to select, identify, or characterize other RNA polymerase II mutations (11,15,20). An a-amanitin resistance mutation in RNA polymerase II has also been used for the chromosomal mapping (11) and molecular cloning (25) of DNA encoding the largest subunit (10) of Drosophila melanogaster RNA polymerase II.Previous studies in this laboratory showed that the RNA polymerase II DNA from the D. melanogaster RP021 (also called RpII215 in reference 2) locus hybridized to mammalian DNA. Using DNA-mediated gene transfer, we identified cross-hybridizing restriction fragments in DNA from Chinese hamster ovary (CHO), Syrian hamster, and human cells that encode at least part of the mammalian RNA polymerase II polypeptide (16). Subsequently this D. melanogaster DNA was used to isolate the analogous polymerase II genes from Saccharomyces cerevisiae (17), human (4), and mouse (5) cells. Nucleotide-sequencing studies of the yeast genes RP021 and RP031 (la), which encode the largest subunit of RNA polymerase II (la,17) and RNA polymerase III (21), respectively, and a similar analysis of a portion of the D. melanogaster RP021 DNA (2) established that the eucaryotic RNA polymerase polypeptides are remarkably similar in * Corresponding author. their primary structure to the analogous subunit of the Escherichia coli RNA polymerase, ,B'. In addition, the largest subunit of yeast (la) and mouse (5) RNA polymerase II was found to contain a C-terminal extension. This domain consists of an evolutionarily conserved, tandemly repeated heptapeptide sequence with the consensus sequence TyrSer-Pro-Thr-Ser-Pro-Ser.In the present study we report the isolation of DNA encoding the Chinese hamster RNA polymerase II RP021 polypeptide and the nucleotide sequences of the 3' portion of both this hamster gene and the D. melanogaster gene. Like the RP021 polypeptide of S. cerevisiae

In this study, we show that all-trans-retinoic acid (RA) is a potent inducer of tissue transglutaminase (TGase II) and apoptosis in the rat tracheobronchial epithelial cell line SPOC-1. We demonstrate that these cells express the retinoid receptors RAR alpha, RAR gamma, and RXR beta. To identify which of these receptors are involved in regulating these processes, we analyzed the effects of several receptor-selective agonists, an antagonist, and a dominant-negative RAR alpha. We show that the RAR-selective retinoid SRI-6751-84 strongly increased TGase II expression at both the protein and mRNA levels, whereas the RXR-selective retinoid SR11217 had little effect. The RAR alpha-selective retinoid Ro40-6055 was also able to induce TGase II, whereas the RAR gamma-selective retinoid CD437 was inactive. The induction of TGase II by the RAR-selective retinoid was completely inhibited by the RAR alpha-antagonist Ro41-5253. Overexpression of a truncated RAR alpha gene with dominant-negative activity also inhibited the induction of TGase II expression. The increase in TGase II is associated with an induction of apoptosis as revealed by DNA fragmentation and the generation of apoptotic cells. We demonstrate that apoptosis is affected by retinoids in a manner similar to TGase II. Our results suggest that the induction of TGase II expression and apoptosis in SPOC-1 cells are mediated through an RAR alpha-dependent signaling pathway.

Influenza remains a serious public health threat throughout the world. Vaccines and antivirals are available that can provide protection from infection. However, new viral strains emerge continuously because of the plasticity of the influenza genome, which necessitates annual reformulation of vaccine antigens, and resistance to antivirals can appear rapidly and become entrenched in circulating virus populations. In addition, the spread of new pandemic strains is difficult to contain because of the time required to engineer and manufacture effective vaccines. Monoclonal antibodies that target highly conserved viral epitopes might offer an alternative protection paradigm. Herein we describe the isolation of a panel of monoclonal antibodies derived from the IgG + memory B cells of healthy, human subjects that recognize a previously unknown conformational epitope within the ectodomain of the influenza matrix 2 protein, M2e. This antibody binding region is highly conserved in influenza A viruses, being present in nearly all strains detected to date, including highly pathogenic viruses that infect primarily birds and swine, and the current 2009 swine-origin H1N1 pandemic strain (S-OIV). Furthermore, these human anti-M2e monoclonal antibodies protect mice from lethal challenges with either H5N1 or H1N1 influenza viruses. These results suggest that viral M2e can elicit broadly cross-reactive and protective antibodies in humans. Accordingly, recombinant forms of these human antibodies may provide useful therapeutic agents to protect against infection from a broad spectrum of influenza A strains.