Sublingual allergen immunotherapy prevents house dust mite inhalant type 2 immunity through dendritic cell-mediated induction of Foxp3+ regulatory T cells.

Sublingual allergen immunotherapy (SLIT) is an emerging treatment option for allergic asthma and a potential disease-modifying strategy for asthma prevention. The key cellular events leading to such long-term tolerance remain to be fully elucidated. We administered prophylactic SLIT in a mouse model of house dust mite (HDM)-driven allergic asthma. HDM extract was sublingually administered over 3 weeks followed by intratracheal sensitization and intranasal challenges with HDM. Prophylactic SLIT prevented allergic airway inflammation and hyperreactivity with a low lab-to-lab variation. The HDM-specific T helper (Th)2 (cluster of differentiation 4 Th) response was shifted by SLIT toward a regulatory and Th17 response in the lung and mediastinal lymph node. By using Derp1-specific cluster of differentiation 4+ T cells (1-DER), we found that SLIT blocked 1-DER T cell recruitment to the mediastinal lymph node and dampened IL-4 secretion following intratracheal HDM sensitization. Sublingually administered Derp1 protein activated 1-DER T cells in the cervical lymph node via chemokine receptor7+ migratory dendritic cells (DC). DCs migrating from the oral submucosa to the cervical lymph node after SLIT-induced Foxp3+ regulatory T cells. When mice were sensitized with HDM, prior prophylactic SLIT increased Derp1 specific regulatory T cells (Tregs) and lowered Th2 recruitment in the lung. By using Foxp3-diphtheria toxin receptor mice, Tregs were found to contribute to the immunoregulatory prophylactic effect of SLIT on type 2 immunity. These findings in a mouse model suggest that DC-mediated functional Treg induction in oral mucosa draining lymph nodes is one of the driving mechanisms behind the disease-modifying effect of prophylactic SLIT.

Factors Influencing Patient Satisfaction With Breast Augmentation: A BREAST-Q Effect of Magnitude Analysis.

BACKGROUND: Breast augmentation is one of the most performed cosmetic surgeries. Despite this, patient satisfaction following breast augmentation is poorly understood. OBJECTIVES: The aim of this study was to investigate what patient and surgical factors influence patient satisfaction following primary breast augmentation. METHODS: The BREAST-Q Augmentation module was sent to all females undergoing primary breast augmentation at a single private clinic (Amalieklinikken, Copenhagen, Denmark) between 2012 and 2019. Patient and surgical characteristics at the time of surgery were obtained from the patients' medical records, and data on factors that occurred after the surgery (eg, breastfeeding) were obtained by patient contact. Multivariate linear regression modeled the impact of these factors on BREAST-Q outcomes. RESULTS: A total of 554 females with a mean follow-up time of 5 years after primary breast augmentation were included in this study. Implant type and volume did not affect patient satisfaction. However, higher patient age was associated with significantly higher postoperative patient satisfaction, psychosocial well-being, and sexual well-being (P < .05). Conversely, higher patient BMI, postoperative weight gain, and breastfeeding were associated with significantly lower satisfaction (P < .05). Additionally, subglandular implant placement was associated with significantly lower satisfaction than submuscular implant placement (P < .05). CONCLUSIONS: Implant type and volume did not affect patient satisfaction with breast augmentation. However, young age, higher BMI, subglandular implant placement, and postoperative weight gain were associated with lower patient satisfaction. These factors should be considered when aligning outcome expectations with breast augmentation.

Hematoma and deep surgical site infection following primary breast augmentation: A retrospective review of 1128 patients.

BACKGROUND: Breast augmentation is one of the most frequently performed cosmetic surgery worldwide. Some of the most severe short-term complications after breast augmentation are hematoma and deep surgical site infection. However, these complications are relatively rare; therefore, large patient populations are required to perform statistical analyses. In this study, we provide a detailed analysis of the complications after primary breast augmentation with an emphasis on deep surgical site infection and hematoma. METHOD: We retrospectively reviewed the medical records of women who underwent primary breast augmentation without the use of pocket irrigation between 2012 and 2019 in a single private clinic. A cumulative hazard function and a multivariate analysis on the risk of hematoma were performed. RESULTS: We included 1128 patients in the study. Thirty patients (2.7%) developed postoperative hematoma after a median time of 14 h (IQR 5 h-9 days). Six patients (0.5%) contracted a deep surgical site infection after a median time of 14 days (range 4-41 days). Age, BMI, implant volume, or implant placement was not significantly associated with hematoma. CONCLUSION: Our findings support that the risk of hematoma after primary breast augmentation is highest within the first 24 h after the surgery. This time period should be considered when planning postoperative care for these patients. We did not find an increased rate of deep surgical site infection compared with studies of breast augmentations with pocket irrigation. Further studies and meta-analyses are needed to explore the effect of pocket irrigation and other risk factors.

Breast Augmentation with Microtextured Anatomical Implants in 653 Women: Indications and Risk of Rotation.

BACKGROUND: Anatomical implants provide a wide range of options in terms of implant dimensions for breast augmentation. Nevertheless, many surgeons choose not to use anatomical implants due to the risk of rotation malposition and because their advantages over round implants are not clearly defined. METHODS: A retrospective review of medical records was performed on all women who underwent breast augmentation or implant exchange with microtextured anatomical implants from 2012 to 2019 in a single private clinic. The authors focused on the outcomes of a subgroup of women with glandular ptosis and nipple placement below the inframammary fold who underwent breast augmentation with anatomical implants. Furthermore, the incidence and risk factors for implant rotation were analyzed. RESULTS: In total, 653 women underwent primary breast augmentation (n = 529) or implant exchange (n = 124) with anatomical implants. The median follow-up period was 2.7 years (interquartile range, 1.6 to 3.9 years). The incidence of implant rotation was 14 (2.6 percent) in the primary augmentation group and four (3.2 percent) in the implant exchange group. Implant rotation was not associated with type of surgery (p = 0.76), implant projection (p = 0.23), or implant height (p = 0.48). The authors successfully used anatomical implants to elevate the nipple in 92.9 percent of the women with glandular ptosis without using a mastopexy. CONCLUSIONS: The study results indicate that the rotation risk with microtextured implants is similar to that with macrotextured implants. Furthermore, the authors found that high-projection anatomical implants can be used as an alternative to augmentation-mastopexy in women with glandular ptosis. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Allergen-specific IgG+ memory B cells are temporally linked to IgE memory responses.

BACKGROUND: IgE is the least abundant immunoglobulin and tightly regulated, and IgE-producing B cells are rare. The cellular origin and evolution of IgE responses are poorly understood. OBJECTIVE: The cellular and clonal origin of IgE memory responses following mucosal allergen exposure by sublingual immunotherapy (SLIT) were investigated. METHODS: In a randomized double-blind, placebo-controlled, time course SLIT study, PBMCs and nasal biopsy samples were collected from 40 adults with seasonal allergic rhinitis at baseline and at 4, 8, 16, 28, and 52 weeks. RNA was extracted from PBMCs, sorted B cells, and nasal biopsy samples for heavy chain variable gene repertoire sequencing. Moreover, mAbs were derived from single B-cell transcriptomes. RESULTS: Combining heavy chain variable gene repertoire sequencing and single-cell transcriptomics yielded direct evidence of a parallel boost of 2 clonally and functionally related B-cell subsets of short-lived IgE+ plasmablasts and IgG+ memory B cells. Mucosal grass pollen allergen exposure by SLIT resulted in highly diverse IgE and IgGE repertoires. These were extensively mutated and appeared relatively stable as per heavy chain isotype, somatic hypermutations, and clonal composition. Single IgGE+ memory B-cell and IgE+ preplasmablast transcriptomes encoded antibodies that were specific for major grass pollen allergens and able to elicit basophil activation at very low allergen concentrations. CONCLUSION: For the first time, we have shown that on mucosal allergen exposure, human IgE memory resides in allergen-specific IgG+ memory B cells. These cells rapidly switch isotype, expand into short-lived IgE+ plasmablasts, and serve as a potential target for therapeutic intervention.

Novel staphylococcal glycosyltransferases SdgA and SdgB mediate immunogenicity and protection of virulence-associated cell wall proteins.

Infection of host tissues by Staphylococcus aureus and S. epidermidis requires an unusual family of staphylococcal adhesive proteins that contain long stretches of serine-aspartate dipeptide-repeats (SDR). The prototype member of this family is clumping factor A (ClfA), a key virulence factor that mediates adhesion to host tissues by binding to extracellular matrix proteins such as fibrinogen. However, the biological siginificance of the SDR-domain and its implication for pathogenesis remain poorly understood. Here, we identified two novel bacterial glycosyltransferases, SdgA and SdgB, which modify all SDR-proteins in these two bacterial species. Genetic and biochemical data demonstrated that these two glycosyltransferases directly bind and covalently link N-acetylglucosamine (GlcNAc) moieties to the SDR-domain in a step-wise manner, with SdgB appending the sugar residues proximal to the target Ser-Asp repeats, followed by additional modification by SdgA. GlcNAc-modification of SDR-proteins by SdgB creates an immunodominant epitope for highly opsonic human antibodies, which represent up to 1% of total human IgG. Deletion of these glycosyltransferases renders SDR-proteins vulnerable to proteolysis by human neutrophil-derived cathepsin G. Thus, SdgA and SdgB glycosylate staphylococcal SDR-proteins, which protects them against host proteolytic activity, and yet generates major eptopes for the human anti-staphylococcal antibody response, which may represent an ongoing competition between host and pathogen.

Isolation of human antibody repertoires with preservation of the natural heavy and light chain pairing.

The humoral immune system in higher vertebrates is unique in its ability to generate highly diverse antibody responses against most pathogens as well as against certain malignancies. Several technologies have been developed to exploit this vast source of potentially therapeutic antibodies, including hybridoma technology, phage display and yeast display. Here, we present a novel, high-throughput technology (the Symplex Technology) for rapid direct cloning and identification of human antigen-specific high-affinity antibodies from single antibody-producing cells of immune individuals. The utility of the technology was demonstrated by isolation of diverse sets of unique high-affinity antibodies against tetanus toxoid and influenza virus from immunized volunteers. Hence, the Symplex Technology is a new method for the rapid isolation of high-affinity antibodies directly from humans.

TCR comodulation of nonengaged TCR takes place by a protein kinase C and CD3 gamma di-leucine-based motif-dependent mechanism.

One of the earliest events following TCR triggering is TCR down-regulation. However, the mechanisms behind TCR down-regulation are still not fully known. Some studies have suggested that only directly triggered TCR are internalized, whereas others studies have indicated that, in addition to triggered receptors, nonengaged TCR are also internalized (comodulated). In this study, we used transfected T cells expressing two different TCR to analyze whether comodulation took place. We show that TCR triggering by anti-TCR mAb and peptide-MHC complexes clearly induced internalization of nonengaged TCR. By using a panel of mAb against the Ti beta chain, we demonstrate that the comodulation kinetics depended on the affinity of the ligand. Thus, high-affinity mAb (K(D) = 2.3 nM) induced a rapid but reversible comodulation, whereas low-affinity mAb (K(D) = 6200 nM) induced a slower but more permanent type of comodulation. Like internalization of engaged TCR, comodulation was dependent on protein tyrosine kinase activity. Finally, we found that in contrast to internalization of engaged TCR, comodulation was highly dependent on protein kinase C activity and the CD3 gamma di-leucine-based motif. Based on these observations, a physiological role of comodulation is proposed and the plausibility of the TCR serial triggering model is discussed.

Minor structural changes in a mutated human melanoma antigen correspond to dramatically enhanced stimulation of a CD4+ tumor-infiltrating lymphocyte line.

While most immunotherapies for cancer have focused on eliciting specific CD8+ cytotoxic T lymphocyte killing of tumor cells, a mounting body of evidence suggests that stimulation of anti-tumor CD4+ T cell help may be required for highly effective therapy. Several MHC class II-restricted tumor antigens that specifically activate such CD4+ helper T lymphocytes have now been identified, including one from a melanoma tumor that is caused by a single base-pair mutation in the glycolytic enzyme triosephosphate isomerase. This mutation results in the conversion of a threonine residue to isoleucine within the antigenic epitope, concomitant with a greater than five log-fold increase in stimulation of a CD4+ tumor-infiltrating lymphocyte line. Here, we present the crystal structures of HLA-DR1 in complex with both wild-type and mutant TPI peptide antigens, the first structures of tumor peptide antigen/MHC class II complexes recognized by CD4+ T cells to be reported. These structures show that very minor changes in the binding surface for T cell receptor correspond to the dramatic differences in T cell stimulation. Defining the structural basis by which CD4+ T cell help is invoked in an anti-tumor immune response will likely aid the design of more effective cancer immunotherapies.