A screen of cell surface markers differentially expressed during peripheral B cell differentiation identified that the CD45RB epitope detected by the mAb MEM-55 was highly expressed on CD27+ memory B cells and absent on CD27- naïve B cells. IgG+CD27- memory and a previously unacknowledged CD27- population in blood also expressed high levels of CD45RBMEM55. Naïve and memory B cells from tonsils fol

Background To accurately interpret COVID-19 seroprevalence surveys, knowledge of serum-IgG responses to SARS-CoV-2 with a better understanding of patients who do not seroconvert, is imperative. This study aimed to describe serum-IgG responses to SARS-CoV-2 in a cohort of patients with both severe and mild COVID-19, including extended studies of patients who remained seronegative more than 90 days

Adjuvants have traditionally been appreciated for their immunoenhancing effects, whereas their impact on immunological memory has largely been neglected. In this paper, we have compared three mechanistically distinct adjuvants: aluminum salts (Alum), Ribi (monophosphoryl lipid A), and the cholera toxin A1 fusion protein CTA1-DD. Their influence on long-term memory development was dramatically diff

Promoter region sequences of human and mouse Igk-V genes were aligned and found to be conserved for about 200-300 base pairs (bp) within subgroups/families. No promoter similarity was found between IGKV promoters from different human subgroups. Related mouse Igk-V gene families were conserved in the promoter region but no similarity was evident when promoters from unrelated Igk-V gene families wer

Recruitment of immune cells to tumors is a complex process crucial for both inflammation-driven tumor progression and specific anti-tumor cytotoxicity. Chemokines control the directed migration of immune cells, and their actions are partly controlled by nonsignaling chemokine decoy receptors. The role of the receptors such as D6, Duffy antigen receptor for chemokines and ChemoCentryx chemokine rec

Our understanding of how class-switch recombination (CSR) to IgA occurs in the gut is still incomplete. Earlier studies have indicated that Tregs are important for IgA CSR and these cells were thought to transform into follicular helper T cells (Tfh), responsible for germinal center formation in the Peyer’s patches (PP). Following adoptive transfer of T-cell receptor-transgenic (TCR-Tg) CD4 T cell

Background: In many studies it would be advantageous if blood samples could be collected and analyzed using flow cytometry at a later stage. Ideally, sample collection should involve little hands-on time, allow for long-term storage, and minimally influence the samples. Methods: Here we establish a flow cytometry antibody panel that can be used to determine granulocytes, monocytes, and lymphocyte

Inspired by the work of Paul Sinclair we yearn for the publication of a guidebook to provide an inventory of Zimbabwe Sites (Sinclair 1987, 1989, 1993, 2010). These sites are the tangible archaeological espression and hence vital evidence of the anatomy of the precolo-nial state in Zimbabwe (Pikirayi 1993, 2001; Pwiti 1996, Mudenge 2011, Beach 1980). The precolonial history of Zimbabwe may be rend

Whereas gut IgA responses to the microbiota may be multi-centered and diverse, little is known about IgA responses to T-cell-dependent antigens following oral immunizations. Using a novel approach, gut IgA responses to oral hapten (4-hydroxy-3-nitrophenyl)acetyl-cholera toxin (NP-CT) conjugates were followed at the cellular and molecular level. Surprisingly, these responses were highly synchronize

Somatic hypermutation and isotype switch recombination occur in germinal center B cells, are linked to transcription, and are similarly affected by deficiency in MutS homologue (MSH)2. Class-switch recombination is abrogated by disruption of genes encoding components of the catalytic subunit of DNA-dependent protein kinase (DNA-PK(cs))/Ku complex and likely involves nonhomologous end joining (NHEJ

Most antibodies produced in the body are of the IgA class. The dominant cell population producing them are plasma cells within the lamina propria of the gastrointestinal tract, but many IgA-producing cells are also found in the airways, within mammary tissues, the urogenital tract and inside the bone marrow. Most IgA antibodies are transported into the lumen by epithelial cells as part of the muco

A novel Ets protein was isolated by yeast one-hybrid screening of a cDNA library made from lipopolysaccharide-stimulated mouse splenic B cells, using the SP6 κ promoter κY element as a bait. The novel Ets protein was most closely related to PU.1 and Spi-B within the DNA binding Ets domain and was therefore named Spi-C. However, Spi-C may represent a novel subgroup within the Ets protein family, as

Neuroblastoma is the most commonly diagnosed extracranial tumor in the first year of life. Approximately 9% of neuroblastoma patients present germline or somatic aberrations in the gene encoding for anaplastic lymphoma kinase (ALK). This increases in high-risk neuroblastomas, which have a 14% frequency of ALK aberrations at the time of diagnosis and show increasing numbers at relapse. Abrogating A

Haematopoietic stem cell transplantation (HSCT) is an immunological treatment that has been used for more than 40 years to cure a variety of diseases. The procedure is associated with serious side effects, due to the severe impairment of the immune system induced by the treatment. After a conditioning regimen with high-dose chemotherapy, sometimes in combination with total body irradiation, haemat

In this article, Mats Bemark and Tomas Leanderson discuss the levels at which immunoglobulin gene transcription is controlled, and highlight the complex nature and mode of action of immunoglobulin promoters.

Switched antibody classes are important for efficient immune responses. Aberrant antibody production to otherwise harmless antigens may result in autoimmunity. The protein kinase fms-like tyrosine kinase 3 receptor (Flt3) has an important role during early B-cell development, but the role of Flt3 in peripheral B cells has not been assessed before. Herein we describe a previously unappreciated role

Two C57BL/6 mice colonies maintained in two rooms of the same specific pathogen-free (SPF) facility were found to have different gut microbiota and a mucus phenotype that was specific for each colony. The thickness and growth of the colon mucus were similar in the two colonies. However, one colony had mucus that was impenetrable to bacteria or beads the size of bacteria - which is comparable to wh

Recently, we reported that CD40-/- mice, exhibiting exclusively T cell-independent IgA class switch recombination (CSR), demonstrated near normal levels of IgA plasma cells in the gut lamina propria (LP), despite the complete lack of germinal centers (GCs). In this study, we have extended our analysis focusing on how to reconcile these findings using flow cytometry and molecular markers for IgA CS

Gut-derived antigens trigger immunoglobulin A (IgA) immune responses that are initiated by cognate B cells in Peyer’s patches (PPs). These cells colonize the subepithelial domes (SEDs) of the PPs and subsequently infiltrate pre-existing germinal centers (GCs). Here we defined the pre-GC events and the micro-anatomical site at which affinity-based B cell selection occurred in PPs. Using whole-organ

By mutational analysis of the octamer-TATA box intervening region in the mouse SP6 κ promoter, we have mapped two octamer-dependent, costimulatory regions, A and B. The A region was active in late B cells only, while the B region was active throughout B cell differentiation. The B region was TATA proximal and contained a heptamer and an E box of the E2A type that is common in Vκ promoters. Mutatio