The immune system is dysfunctional for years after hematopoietic stem cell transplantation (HSCT). A potential cause is an intrinsic B cell deficiency. In a cohort of pediatric HSCT patients few CD27+ B cells formed after transplantation with the number of CD27+IgMhigh cells more affected than class-switched ones. A previously unacknowledged population of CD27-IgMhigh cells made up the majority of

Immunoglobulin κ promoters show sequence divergence but conserved function between different subgroups. Here we show that three separate 5' elements are required for synergistic stimulation of transcription with the decamer in a κ promoter. These sites are a 5' E-box, a 3' AT-rich region in the pentadecamer (pd) element, and the κ-Y element. Elf-1 is a novel κ-Y element ligand induced upon mitogen

The intact SP6 χ promoter stimulated transcription 30 times more efficiently than did a control promoter consisting of a TATA motif as the only promoter element. Mutation of the SP6 χ promoter decamer in two positions reduced the transcriptional stimulation activity by over 90%. Promoters containing the SP6 χ promoter octamer or a consensus octamer in front of a TATA box were ineffective immunoglo

A prime function of the mucosal immune system is the production of secretory immunoglobulin (Ig) A antibodies. To initiate this, the organized lymphoid system is strategically located at sites where mucosal antigens are encountered. The follicle-associated epithelium (FAE) hosts specialized cells called M cells that effectively take up antigen. After transport of antigen via the FAE, the mucosal-a

Multiple DNA polymerases exist in eukaryotes. Polymerases α, δ and ε are mainly responsible for chromosomal DNA replication in the nucleus and are required for proliferation. In contrast, the repair polymerases β and η are not essential for cellular proliferation in yeast or mice, but a lack of either polymerase can lead, respectively, to defects in base excision repair or the ability to replicate

The GAGA box of the rat serine protease inhibitor 2 (spi 2) genes not only acts as a basal promoter element, but also mediates transcriptional activation by growth hormone and interleukin-6. The GAGA box is separated from the TATA box by only 12 bp, and this close association is required for efficient transcription. Hence, the GAGA box may influence transcription efficiency through interactions be

The SP6 κ-promoter pentadecamer (pd) element was found to be unable to stimulate transcription when present in one copy as the only promoter element in a minimal promoter but showed weak stimulatory activity when present as a multimer (four copies). One copy of the pd element acted synergistically with an octamer element, but not with a SP1 site, to stimulate transcription. The effect was orientat

The gut immune system protects against mucosal pathogens, maintains a mutualistic relationship with the microbiota, and establishes tolerance against food antigens. This requires a balance between immune effector responses and induction of tolerance. Disturbances of this strictly regulated balance can lead to infections or the development inflammatory diseases and allergies. Production of secretor

DNA interstrand cross-links (ICLs) are the most cytotoxic lesions to eukaryotic genome and are repaired by both homologous recombination-dependent and -independent mechanisms. To better understand the role of lesion bypass polymerases in ICL repair, we investigated recombination-independent repair of ICLs in REV3 and REV1 deletion mutants constructed in avian DT40 cells and mouse embryonic fibrobl

The catalytic subunit of polymerase ζ is encoded from the Rev3 gene. The enzyme is conserved through eukaryotic evolution and its main function appears to be translesion synthesis (TLS) over damaged bases that stall DNA replication. In non-vertebrate cells, inactivation of polymerase ζ results in a moderate hypersensitivity to DNA damage but no proliferative defect in the absence of exogenous dama

The germinal center (GC) reaction in Peyer′s patches (PP) requires continuous access to antigens, but how this is achieved is not known. Here we show that activated antigen-specific CCR6+CCR1+GL7− B cells make close contact with M cells in the subepithelial dome (SED). Using in situ photoactivation analysis of antigen-specific SED B cells, we find migration of cells towards the GC. Following antig

During the last two decades our understanding of human B cell differentiation has developed considerably. Our understanding of the human B cell compartment has advanced from a point where essentially all assays were based on the presence or not of class-switched antibodies to a level where a substantial diversity is appreciated among the cells involved. Several consecutive transitional stages that

The physiological mechanism for producing antigen-specific antibodies is based on a two-phase neo-Darwinian process: the first phase consists of diversity generation (formation of the repertoire), and the second phase is antigen-mediated selection. In this article, we consider how the natural immunoglobulin gene-diversification processes can be exploited both in vivo and in vitro in order to allow

Because Peyer's patches (PP) are the main inductive sites for gut IgA responses we have focused this review on what we know about the function of PP germinal centers (GC).The vast majority of IgA gene sequences in the gut lamina propria (LP) are heavily mutated arguing for an origin in GC. Because PP GC formation is dependent on the presence of CD4 T cells, we speculate that all IgA responses in t

Abstract In this study we present new palaeointensity measurements on Iron Age (200 AD – 1840 AD) pottery from the southern Africa region, where there is only limited data available at present. Many sites only produce a single accepted palaeointensity result and we have therefore opted to focus on analysis at sample level as opposed to site level, which is more common in traditional archaeomagneti

The first mass-distributed vaccines based on mRNA technology were launched in 2021 to protect against COVID-19, sparking rumours among vaccine critical individuals that these “new” vaccines might be more dangerous to the health than other, “traditional” vaccines. Drawing on rumour theories and social cognitive perspectives, the aim of this chapter is to account for the purpose and the spreading of

Cancer cells evade the immune system by downregulating antigen presentation. Although immune checkpoint inhibitors (ICI) and adoptive T-cell therapies revolutionized cancer treatment, their efficacy relies on the intrinsic immunogenicity of tumor cells and antigen presentation by dendritic cells. Here, we describe a protocol to directly reprogram murine and human cancer cells into tumor-antigen-pr

This chapter provides examples of basic analyses of macro and micro levels of intermediality in social media: YouTube entertainment, an example of a multi-layered social media practice, and GIFs, which derive from other media and migrate across different platforms on the internet. Apart from media combination and integration, even the two aspects of media transformation, transmediation and represe

Carriers of BRCA1 germline pathogenic variants are at substantially higher risk of developing breast and ovarian cancer than the general population. Accurate identification of at-risk individuals is crucial for risk stratification and the implementation of targeted preventive and therapeutic interventions. Despite significant progress in variant classification efforts, a sizable portion of reporte