Evaluation of B-Cell Kinetics After Acellular Pertussis Vaccination in Four Cohorts of Different Age and Priming Background

Pertussis is a vaccine-preventable disease caused by the bacterium Bordetella pertussis. Over the past years, the incidence and mortality of pertussis increased significantly. A possible cause is the switch from whole cell to acellular pertussis vaccines, although other factors may also contribute. To develop future vaccines and improve current vaccination strategies, it is critical to understand factors influencing the generation of immunological memory. We applied high-dimensional flow cytometry to investigate changes in B cells in individuals of different ages and distinct priming backgrounds upon administration of an acellular pertussis booster vaccine. These findings were correlated to vaccine-specific plasma cells and serum Ig levels. Expansion and maturation of plasma cells 7 days post-vaccination was the most prominent cellular change in all age groups, and was most pronounced for more mature IgG1+ plasma cells. Cellular responses were stronger in individuals primed with whole cell vaccine than in individuals primed with acellular vaccine. Moreover, IgG1+ plasma cell expansion weakly correlated with Prn- and PT- specific serum IgG levels. Our study points at plasma cells as a potential early cellular marker of an immune response and contributes to understanding differences in immune responses between age groups and priming backgrounds.

1153 “To FNA Or to Not FNA, That Is the Question.” A 5-Year Retrospective Epidemiological Study Of 238 Surgical Parotid Cases Treated at An East Yorkshire OMFS Unit

Introduction Fine needle aspiration (FNA) is a surgical procedure used to aid with diagnosis and subsequent treatment planning. This study compares FNA histology with final histology (gold standard) for diagnostic accuracy in parotid surgery patients. Method A retrospective investigation of patient records from January 2014-January 2019 was performed to find eligible patients that underwent parotid surgery. Histology reports of the ultrasound (US) FNA and final parotid sample were compared for diagnostic accuracy and ability to differentiate between malignant & benign tumours. Results 240 parotid surgeries on 238 patients were undertaken between 2014-2019 under OMFS and ENT specialities. 137 US FNA’s were performed, of these, there was an 85% diagnostic rate. Of the diagnostic FNA’s 79% reach gold standard, with the histology matching that of the final histology. Of the 24 without diagnostic accuracy, 2/3 were still able to differentiate between malignant and benign lesions. Overall, the US FNA’s were able to differentiate malignant and benign parotid lesions in 93% of cases. Conclusions The audit has proven US FNA to be an accurate diagnostic test, it gives extra data to aid in the decision making and planning for parotid surgeries. Although US FNA has shown to be more accurate in diagnosing benign parotid tumours; it is useful in detecting cellular change which could be indicative of malignancy.

Dissociated hippocampal neurons exhibit distinct Zn2+ dynamics in a stimulation method-dependent manner

ABSTRACTIonic Zn2+ has increasingly been recognized as an important neurotransmitter and signaling ion in glutamatergic neuron pathways. Intracellular Zn2+ transiently increases as a result of neuronal excitation, and this Zn2+ signal is essential for neuron plasticity, but the source and regulation of the signal is still unclear. In this study we rigorously quantified Zn2+, Ca2+ and pH dynamics in dissociated mouse hippocampal neurons stimulated with bath application of high KCl or glutamate. While both stimulation methods yielded Zn2+ signals, Ca2+ influx, and acidification, glutamate stimulation induced more sustained high intracellular Ca2+ and a larger increase in intracellular Zn2+. However, the stimulation-induced pH change was similar between conditions, indicating that a different cellular change is responsible for the stimulation-dependent difference in Zn2+ signal. This work provides the first robust quantification of Zn2+ dynamics in neurons using different methods of stimulation.

Cervical Cytopathological Findings in Korean Women withChlamydia trachomatis,Mycoplasma hominis, andUreaplasma urealyticumInfections

This is to investigate the cervical cytological abnormalities associated withChlamydia trachomatis,Mycoplasma hominis,Mycoplasma genitalium,andUreaplasma urealyticuminfections on routine screen. A total of 714 subjects who had undergone cervical Pap smears and concomitant analyses for cervical infections were included by a retrospective search. The frequencies of reactive cellular change (RCC) and squamous epithelial abnormalities were significantly higher inChlamydiapositive subjects than in uninfected subjects(P<0.001). Of the 124 subjects tested forM. hominis,M. genitalium, andU. urealyticum, 14 (11%) were positive forM. hominisand 29 (23%) were positive forU. urealyticum. Squamous abnormalities were more frequent in subjects withUreaplasmainfections than in uninfected subjects (24% versus 8%). Taking together these findings,C. trachomatisandU. urealyticummay have a causal role in the development of cervical epithelial changes, including RCC. Thus, extra awareness is warranted in cervical screening of women withChlamydiaorUreaplasmainfections.

Dissecting the link between nanoparticle lung effects and tumor markers with CD24 measurements.

e21085 Background: It was postulated that carbon nanoparticles (CN) induced mesothelioma-like changes equal to asbestos in mice. We investigated CN added to human mesothelial cells in culture and reported that CN-induced cell damage to untransformed human mesothelial cells is rapidly followed by secretion of tumor markers like mesothelin and osteopontin. In vivo in animals, our group quantifies CN lung damage by HMGB1, an intranuclear protein released into alveolar lavage after CN exposure. Recent work suggests that the cell surface marker CD24 associates with HMGB1 to blunt lung responses to damage (like CN), but does not blunt cell response to pathogen-released HMGB1. Since CD24 is also a known cancer marker, elevated in many malignancies, we hypothesized that the cellular change elicited by CD24 when coupled with a damage marker would offer a mechanism through which CN could produce –repeated over time—malignant change in exposed human mesothelial cells. Such expression would support our previous research efforts. Methods: Untransformed human mesothelial cells were cultured and then stimulated or not with a CN dose giving 80% cell viability. At 24, 48 & 72 hr cells were fixed and stained with anti-CD 24. Presence of positive stain was photographed and counted. CN exposed and control rat lungs were harvested and frozen at 0.5 hr, 3 hr, 24 hr and 4 weeks. Western blot and immunostaining (with Anti-CD24 antibody and mucin chemical stain) was used to measure CD24 levels. Results: In CN-exposed animals, CD24 was highest at 24 hr. Mucin presence confirms the CD24 staining. Homogenates by Western blot also showed highest CD24 reactivity at 24 hr. In CN-exposed cultured cells, at 48 hr, some anti-CD24 staining was seen and at 72 hr in clusters of hyperproliferating cells, strong CD24 stain was seen. Conclusions: Our data suggest, as shown by a second cellular marker CD24, that the mesothelin upregulation seen in our previous studies indicated a cellular change beyond necrosis. Nanoparticles at a dose producing 20% cell death induce this change in healthy human mesothelial cells in culture.

Desmosomal Component Expression in Normal, Dysplastic, and Oral Squamous Cell Carcinoma

Squamous cell carcinoma (oral SCC) is the most common oral cancer in the U.S., affecting nearly 30,000 Americans each year. Despite recent advances in detection and treatment, there has been little improvement in the five-year survival rate for this devastating disease. Oral cancer may be preceded by premalignant disease that appears histologically as dysplasia. Identification of molecular markers for cellular change would assist in determining the risk of dysplasia progressing to oral squamous cell carcinoma. The goal of this study was to determine if any correlation exists between histological diagnosed dysplasia and OSCC lesions and altered expression of desmosomal cell-cell adhesion molecules in the oral epithelium. Our data showed that oral SCC tissue samples showed decreased immunoreactivity of both desmoplakin and plakophilin-1 proteins compared to normal oral epithelium. Furthermore, significant decrease in desmoplakin immunoreactivity was observed in dysplastic tissue compared to normal oral epithelium. In contrast, the level of desmoglein-1 staining was unchanged between samples however desmoglein-1 was found localized to cell borders in oral SCC samples. These data suggest that changes in expression of desmoplakin and plakophilin-1 may prove to be a useful marker for changes in tissue morphology and provide a tool for identifying pre-neoplastic lesions of the oral cavity.