Human NKT cells mediate antitumor cytotoxicity directly by recognizing target cell CD1d with bound ligand or indirectly by producing IL-2 to activate NK cells

alpha-Galactosylceramide (alphaGalCer) stimulates NKT cells and has antitumor activity in mice. Murine NKT cells may directly kill tumor cells and induce NK cell cytotoxicity, but the mechanisms are not well defined. Newly developed human CD1d/alphaGalCer tetrameric complexes were used to obtain highly purified human alphaGalCer-reactive NKT cell lines (>99%), and the mechanisms of NKT cell cytotoxicity and activation of NK cells were investigated. Human NKT cells were cytotoxic against CD1d(-) neuroblastoma cells only when they were rendered CD1d(+) by transfection and pulsed with alphaGalCer. Four other CD1d(-) tumor cell lines of diverse origin were resistant to NKT cells, whereas Jurkat and U937 leukemia cell lines, which are constitutively CD1d(+), were killed. Killing of the latter was greatly augmented in the presence of alphaGalCer. Upon human CD1d/alphaGalCer recognition, NKT cells induced potent cytotoxicity of NK cells against CD1d(-) neuroblastoma cell lines that were not killed directly by NKT cells. NK cell activation depended upon NKT cell production of IL-2, and was enhanced by secretion of IFN-gamma. These data demonstrate that cytotoxicity of human NKT cells can be CD1d and ligand dependent, and that TCR-stimulated NKT cells produce IL-2 that is required to induce NK cell cytotoxicity. Thus, NKT cells can mediate potent antitumor activity both directly by targeting CD1d and indirectly by activating NK cells.

Antibodies to intermediate filament proteins in the immunohistochemical identification of human tumours: an overview

Intermediate-sized filament proteins (IFP) are tissue specific in that antibodies to keratin, vimentin, desmin, glial fibrillary acidic protein (GFAP) and the neurofilament proteins can distinguish between cells of epithelial and mesenchymal origin as well as of myogenic and neural origin respectively. Malignant cells retain their tissue-specific IFP, which makes it possible to use these antibodies in tumour diagnosis. Carcinomas are exclusively detected by antibodies to keratin. Monoclonal antibodies to keratin have allowed the differentiation between subgroups of epithelial tumours until now between adenocarcinomas and squamous cell carcinomas. Lymphomas, melanomas and several soft tissue tumours are distinctly recognized by antibodies to vimentin. On the other hand, rhabdomyosarcomas and leiomyosarcomas are positive for desmin, while astrocytomas give a strong reaction with GFAP antibodies. Thus, antibodies to IFP are useful tools for differential diagnosis in surgical pathology.

Coexpression of keratin- and vimentin-type intermediate filaments in human metastatic carcinoma cells

Metastatic tumor cells of epithelial origin present in effusions from human serous cavity fluids (ascites or pleural fluid) were examined for their intermediate-sized filament types by using antibodies to keratin, vimentin, and desmin in the indirect immunofluorescence technique. Solid epithelial tumors (both primary carcinomas and their metastases) contain keratin intermediate-sized filaments exclusively. However, when these cells are present in ascitic or pleural fluid, they also express vimentin, which occurs in a fibrillar organization. The possible effects of this additional, but temporary, cytoskeleton on metastatic growth or aggressiveness (or both) are discussed.

Occurrence and characteristics of extended-spectrum-β-lactamase- and AmpC-producing clinical isolates derived from companion animals and horses

OBJECTIVES

To investigate the occurrence and characteristics of extended-spectrum β-lactamase (ESBL)- and AmpC-producing Enterobacteriaceae isolates in clinical samples of companion animals and horses and compare the results with ESBL/AmpC-producing isolates described in humans.

METHODS

Between October 2007 and August 2009, 2700 Enterobacteriaceae derived from clinical infections in companion animals and horses were collected. Isolates displaying inhibition zones of ≤ 25 mm for ceftiofur and/or cefquinome by disc diffusion were included. ESBL/AmpC production was confirmed by combination disc tests. The presence of resistance genes was identified by microarray, PCR and sequencing, Escherichia coli genotypes by multilocus sequence typing and antimicrobial susceptibility by broth microdilution.

RESULTS

Sixty-five isolates from dogs (n = 38), cats (n = 14), horses (n = 12) and a turtle were included. Six Enterobacteriaceae species were observed, mostly derived from urinary tract infections (n = 32). All except 10 isolates tested resistant to cefotaxime and ceftazidime by broth microdilution using clinical breakpoints. ESBL/AmpC genes observed were bla(CTX-M-1, -2, -9, -14, -15,) bla(TEM-52), bla(CMY-2) and bla(CMY-)(39). bla(CTX-M-1) was predominant (n = 17). bla(CTX-M-9) occurred in combination with qnrA1 in 3 of the 11 Enterobacter cloacae isolates. Twenty-eight different E. coli sequence types (STs) were found. E. coli carrying bla(CTX-M-1) belonged to 13 STs of which 3 were previously described in Dutch poultry and patients.

CONCLUSIONS

This is the first study among a large collection of Dutch companion animals and horses characterizing ESBL/AmpC-producing isolates. A similarity in resistance genes and E. coli STs among these isolates and isolates from Dutch poultry and humans may suggest exchange of resistance between different reservoirs.

Location of the amino acid differences in the S1 spike glycoprotein subunit of closely related serotypes of infectious bronchitis virus

Four UK strains of three different serotypes were found to differ by only 2-3% of their S1 amino acids. The S1 sequences were also very similar to those of three Dutch isolates (D207, D274 and D3896), the greatest difference between two of the seven isolates being 4.4%. The few amino acid differences between the seven isolates were located largely between residues 19-122 and 251-347 of the mature S1 subunit. The seven isolates could be differentiated using 16 monoclonal antibodies in an enzyme-linked immunosorbent assay. Some virus neutralizing (VN) antibody-inducing epitopes were common to all seven isolates even though the strains had been differentiated into three serotypes by polyclonal sera. The results indicate that the most antigenic of the VN antibody-inducing epitopes are formed by very few amino acids and that these occur in the first and third quarters of the S1 subunit. We suggest that serology-based epizootiological studies of IBV should, therefore, be augmented by the inclusion of nucleic acid sequencing and/or monoclonal antibody analysis.

Antigenic domains on the peplomer protein of avian infectious bronchitis virus: correlation with biological functions

Monoclonal antibodies (MAbs) directed against structural proteins of infectious bronchitis virus (IBV) were produced to analyse the antigenic structure of this virus. Competitive binding of enzyme-labelled and unlabelled MAbs to IBV peplomer protein was analysed in an antibody binding assay to test the relatedness of the epitopes defined by the MAbs. Based on the competition groups, eight epitope clusters were defined (S-A to S-H); six of these clusters (S1-A to S1-F) were located on the S1 subunit and two (S2-G and S2-H) on the S2 subunit of the peplomer protein. Epitope clusters S1-A and S1-B overlapped extensively. The biological activities of the MAbs were determined and correlated to the epitope clusters. Monoclonal antibodies directed against epitope clusters S1-A to S1-E and one MAb directed against cluster S2-G moderately to strongly neutralized IBV at titres higher than 2 log10, whereas the remaining MAbs, directed against S1 and S2, neutralized at titres lower than 2 log10. One MAb, directed against cluster S1-D, inhibited the agglutination of chicken erythrocytes.

Location of antigenic sites defined by neutralizing monoclonal antibodies on the S1 avian infectious bronchitis virus glycopolypeptide

Neutralizing monoclonal antibodies directed against five antigenic sites on the spike (S) S1 glycopolypeptide of avian infectious bronchitis virus (IBV) were used to select neutralization-resistant variants of the virus. By comparing the nucleotide sequence of such variants with the sequence of the IBV parent strain, we located five antigenic sites on the amino acid sequence of the S1 glycopolypeptide. The variants had mutations within three regions corresponding to amino acid residues 24 to 61, 132 to 149 and 291 to 398 of the S1 glycopolypeptide. The location of three overlapping antigenic sites on the IBV spike protein was similar to the location of antigenic sites on the spike protein of other coronaviruses.

A prospective study of outcome from protein-energy malnutrition in nursing home residents

To study recovery from protein-energy malnutrition in patients newly admitted to a chronic care facility, biochemical and anthropomorphic malnutrition indicators were measured prospectively over a 2-month period. Subjects were observed for a mean of 76 +/- 18 days after admission. Factors which might affect nutritional status including method of feeding, energy prescribed, use of supplemental feedings, assistance in eating, and amount of diet consumed were recorded. Confounding variables including illness, mental status, functional status, or prescription drugs were evaluated for their impact. On the basis of an empiric nutrition score, 54% of newly admitted residents were malnourished. Improvement in nutritional score occurred in 63% of malnourished patients remaining in the facility whereas 37% remained malnourished. Two related factors, percentage of diet consumed and degree of assistance required in eating, were important differences in the outcome of patients remaining malnourished. Interventional studies to determine whether outcome can be improved by more aggressive feeding methods or by feeding teams need to be undertaken.

Faecal carriage, risk factors, acquisition and persistence of ESBL-producing Enterobacteriaceae in dogs and cats and co-carriage with humans belonging to the same household

Background

ESBL-producing Enterobacteriaceae (ESBL-E) are observed in many reservoirs. Pets might play an important role in the dissemination of ESBL-E to humans since they live closely together.

Objectives

To identify prevalence, risk factors, molecular characteristics, persistence and acquisition of ESBL-E in dogs and cats, and co-carriage in human–pet pairs belonging to the same household.

Methods

In a nationwide study, one person per household was randomly invited to complete a questionnaire and to submit a faecal sample. Dog and cat owners were invited to also submit a faecal sample from their pet. Repeated sampling after 1 and 6 months was performed in a subset. ESBL-E were obtained through selective culture and characterized by WGS. Logistic regression analyses and random forest models were performed to identify risk factors.

Results

The prevalence of ESBL-E carriage in these cohorts was 3.8% (95% CI: 2.7%–5.4%) for human participants (n=550), 10.7% (95% CI: 8.3%–13.7%) for dogs (n=555) and 1.4% (95% CI: 0.5%–3.8%) for cats (n=285). Among animals, bla_CTX-M-1 was most abundant, followed by bla_CTX-M-15. In dogs, persistence of carriage was 57.1% at 1 month and 42.9% at 6 months. Eating raw meat [OR: 8.8, 95% CI: 4.7–16.4; population attributable risk (PAR): 46.5%, 95% CI: 41.3%–49.3%] and dry food (OR: 0.2, 95% CI: 0.1–0.5; PAR: 56.5%, 95% CI: 33.2%–66.6%) were predictors for ESBL-E carriage in dogs. Human–dog co-carriage was demonstrated in five households. Human–cat co-carriage was not observed.

Conclusions

ESBL-E prevalence was higher in dogs than in humans and lowest in cats. The main risk factor for ESBL-E carriage was eating raw meat. Co-carriage in dogs and household members was uncommon.

Is renal cell (Grawitz) tumor a carcinosarcoma? Evidence from analysis of intermediate filament types

The expression of intermediate filament type was determined in 13 renal cell (Grawitz) tumors (10 primary renal tumors and 3 lymph node metastases). All of the tumors except one lymph node metastasis contained cells expressing vimentin intermediate filaments, generally a marker of mesodermally-derived tissues and their tumors, the sarcomas. In addition, the 10 primary renal tumors and two lymph node metastases contained cells expressing keratin proteins. Using a monoclonal antibody to keratins, specific for glandular epithelial cells, it has been shown that some of the tumor cells resemble adenocarcinomas, at least in this respect. Double immunofluorescence labeling demonstrated that some of the vimentin-containing cells contained keratin while others did not. Only occasional cells were found to contain keratin but not vimentin. However, one of the lymph node metastases was positive only for vimentin. Thus Grawitz tumor cells express intermediate filament types which are generally biological markers of both sarcomatous and carcinomatous tumors.

Intermediate filaments in malignant melanomas. Identification and use as marker in surgical pathology

Intermediate-sized filaments have been studied in human malignant melanomas and in normal melanocytes by immunofluorescence microscopy with antibodies directed against keratin, vimentin, desmin, neurofilament protein, and glial filament protein. Both human melanotic and amelanotic tumor cells and tumor metastases as well as normal melanocytes in human skin and in the rat eye contain exclusively intermediate filaments of the vimentin type. No reaction was seen with antibodies to keratin, desmin, neurofilaments, or glial filaments. These latter four antisera, however, gave strong reactions in epidermis and other epithelial tissues, muscle, or neural tissues, respectively. The results favor a mesenchymal character of melanocytes, although a neuroectodermal origin in an early developmental stage is possible. The finding that melanomas contain exclusively vimentin intermediate filaments may prove useful in differential diagnosis of melanomas from other tumor types.

Treatment resistant depression and axis I co-morbidity

BACKGROUND

Treatment resistant depression (TRD) continues to present a formidable challenge to clinicians, accounts for over half of the annual costs associated with treatment for depression and causes great frustration to patients. Although there have been studies attempting to define TRD, little information is available as to the cause of TRD. One suggestion is that patients with TRD have a greater frequency of co-morbid psychiatric disorders, which explains their resistance to standard antidepressant treatments. The objective of this study was to compare the co-morbidity of Axis I disorders between a sample of TRD patients and a sample of non-TRD patients.

METHODS

TRD and non-TRD patients, recruited from two separate antidepressant treatment studies, were assessed for Axis I co-morbidity using the SCID-P for the DSM-III-R. Patients for the two samples were then matched for baseline HAM-D-17 total score and gender.

RESULTS

Results reveal that non-TRD patients had a higher rate of both lifetime and current generalized anxiety disorder co-morbidity than did the TRD patients. No other statistically significant differences in Axis I co-morbidity were found.

CONCLUSIONS

These findings do not support the idea that current or lifetime Axis I co-morbidity is more common in TRD than non-TRD patients. In fact, the only statistical difference showed non-TRD patients with higher co-morbidity rates.

Patient-Reported Safety Information: A Renaissance of Pharmacovigilance?

The role of patients as key contributors in pharmacovigilance was acknowledged in the new EU pharmacovigilance legislation. This contains several efforts to increase the involvement of the general public, including making patient adverse drug reaction (ADR) reporting systems mandatory. Three years have passed since the legislation was introduced and the key question is: does pharmacovigilance yet make optimal use of patient-reported safety information? Independent research has shown beyond doubt that patients make an important contribution to pharmacovigilance signal detection. Patient reports provide first-hand information about the suspected ADR and the circumstances under which it occurred, including medication errors, quality failures, and 'near misses'. Patient-reported safety information leads to a better understanding of the patient's experiences of the ADR. Patients are better at explaining the nature, personal significance and consequences of ADRs than healthcare professionals' reports on similar associations and they give more detailed information regarding quality of life including psychological effects and effects on everyday tasks. Current methods used in pharmacovigilance need to optimise use of the information reported from patients. To make the most of information from patients, the systems we use for collecting, coding and recording patient-reported information and the methodologies applied for signal detection and assessment need to be further developed, such as a patient-specific form, development of a severity grading and evolution of the database structure and the signal detection methods applied. It is time for a renaissance of pharmacovigilance.

Differential diagnosis of human carcinomas, sarcomas and their metastases using antibodies to intermediate-sized filaments

Intermediate filaments (IF) are tissue-specific in so far that epithelial, mesenchymal, muscle and neural tissue types can be distinguished by the use of specific antibodies to keratin, vimentin, desmin and neurofilaments or glial filaments respectively. We have examined the possibility of using these sera in the differential diagnosis of human malignant tumors. Using antisera to human skin keratin and bovine lens vimentin we could differentiate between carcinomas (keratin +) and sarcomas (vimentin +). Furthermore, we could show that when cells become malignant and metastasize they retain their original IF and do not develop additional IF systems. We conclude that antibodies to IF proteins are powerful tools in the hands of a pathologist as an additional method to improve identification of tumors and their metastases.

Description of Frequencies of Reported Adverse Events Following Immunization Among Four Different COVID-19 Vaccine Brands

INTRODUCTION

The rapid rollout of coronavirus disease 2019 (COVID-19) vaccines for a large proportion of the population necessitates a strong emphasis on safety. Complementary to the existing spontaneous reporting system, The Netherlands Pharmacovigilance Centre Lareb conducted patient-reported cohort event monitoring (CEM).

OBJECTIVE

The primary aim was to investigate differences in the frequencies of any and commonly reported, 'well-known', systemic adverse events following immunization (AEFIs) with four COVID-19 vaccines (Pfizer's Comirnaty®, Moderna's Spikevax®, AstraZeneca's Vaxzevria® and the Janssen vaccine). As a secondary aim, we analyzed the frequencies of well-known systemic adverse events after the first and, if applicable, second COVID-19 vaccinations, taking into account age, sex and prior COVID-19 infection.

METHODS

Patient-reported outcomes (PROs) in the Netherlands starting in February 2021 were analyzed using a prospective cohort design.

RESULTS

Data of 27,554 participants who received one vaccination and 20,682 participants who received complete immunization were analyzed. The percentage of patients reporting any AEFI was high and ranged from approximately 53% for the Pfizer vaccine to approximately 94% for the Moderna vaccine. The frequency of serious AEFIs was low, with the highest frequency found for the AstraZeneca vaccine (0.228%). AEFIs were most often experienced by participants receiving the first dose of the AstraZeneca and Janssen vaccines and the second dose of the Moderna vaccine; the Pfizer vaccine was associated with the lowest rate of AEFIs. Participants with a COVID-19 history before vaccination experienced commonly reported systemic AEFIs more frequently after the first vaccination than after the second vaccination. Women and young people experienced more AEFIs than men and older people, respectively.

CONCLUSIONS

The analysis of a large cohort provides important information about the rates of AEFIs across age groups, among brands of vaccines and between those with and without prior COVID-19 infection. Participants reported a high number of AEFIs in general, but the frequency of serious AEFIs was low.

Sex-disaggregated outcomes of adverse events after COVID-19 vaccination: A Dutch cohort study and review of the literature

Background

Albeit the need for sex-disaggregated results of adverse events after immunization (AEFIs) is gaining attention since the COVID-19 pandemic, studies with emphasis on sexual dimorphism in response to COVID-19 vaccination are relatively scarce. This prospective cohort study aimed to assess differences in the incidence and course of reported AEFIs after COVID-19 vaccination between males and females in the Netherlands and provides a summary of sex-disaggregated outcomes in published literature.

Methods

Patient reported outcomes of AEFIs over a six month period following the first vaccination with BioNTech-Pfizer, AstraZeneca, Moderna or the Johnson&Johnson vaccine were collected in a Cohort Event Monitoring study. Logistic regression was used to assess differences in incidence of 'any AEFI', local reactions and the top ten most reported AEFIs between the sexes. Effects of age, vaccine brand, comorbidities, prior COVID-19 infection and the use of antipyretic drugs were analyzed as well. Also, time-to-onset, time-to-recovery and perceived burden of AEFIs was compared between the sexes. Third, a literature review was done to retrieve sex-disaggregated outcomes of COVID-19 vaccination.

Results

The cohort included 27,540 vaccinees (38.5% males). Females showed around two-fold higher odds of having any AEFI as compared to males with most pronounced differences after the first dose and for nausea and injection site inflammation. Age was inversely associated with AEFI incidence, whereas a prior COVID-19 infection, the use of antipyretic drugs and several comorbidities were positively associated. The perceived burden of AEFIs and time-to-recovery were slightly higher in females.

Discussion

The results of this large cohort study correspond to existing evidence and contribute to the knowledge gain necessary to disentangle the magnitude of the effect sex in response to vaccination. Whilst females have a significant higher probability of experiencing an AEFI than males, we observed that the course and burden is only to a minor extent different between the sexes.

Immunocytochemical demonstration of intermediate filaments in a granular cell ameloblastoma

The nature and location of intermediate filament proteins (IFP) may provide new insights into the origin and differentiation of neoplastic cells. An immunofluorescent study of these IFP in a case of a granular cell ameloblastoma revealed that all tumor cells contained the IFP keratin. Some granular cells, however, also contained the IFP vimentin, which is considered specific for mesenchymal tissues only. The implications of these observations are discussed. Study with monoclonal antibodies indicated the origin of the ameloblastoma from non-keratinized squamous epithelium. A comparison of the anti-keratin immunofluorescence pattern of the ameloblast-like cells in the present tumor with ameloblasts in the tooth germ revealed no similarities, indicating that despite some resemblance of the peripheral columnar cells to ameloblasts, these cells differ in other aspects.

COVID-19 vaccine reactogenicity - A cohort event monitoring study in the Netherlands using patient reported outcomes

Objectives

To explore factors that are associated with reactogenicity in general and systemic after the first dose of COVID-19 vaccine in the Netherlands.

Design

A web-based prospective cohort design using patient reported outcomes (PROs).

Setting

Any person who has been vaccinated with any brand of COVID-19 vaccine in the Dutch COVID immunization programme.

Participants

22,184 participants. Of these, 13,959 (62.9%) experienced reactogenicity in general and 11,979 (54.0%) systemic reactogenicity within 7 days after vaccination.

Main outcome measures

Factors that are associated with the occurrence of reactogenicity after COVID-19 vaccination.

Results

Compared to the Comirnaty® vaccine, the highest odds ratio (OR) for developing reactogenicity was for the Vaxzevria® vaccine (OR 5.18) followed by Spikevax® (OR 2.16), and Janssen (OR 1.65). Participants with a history of COVID-19 disease had a 3.10 increased odds for reactogenicity. Women had a 2.08 increased odds compared to men. Older participants experienced less reactogenicity. Compared to the age group < 50, the ORs for the age groups 50–60, 61–79, and ≥80 were 0.36, 0.15, and 0.10 respectively. The use of an antipyretic drug, or a drug for nervous system disorders gave an increased odds of 1.34 and 1.16 respectively. A body mass index of 25.0–29.9 and over 30 was negatively associated with reactogenicity (OR 0.87 and OR 0.72 respectively). Comorbidities that were associated with reactogenicity were cardiac disorders (OR 1.26), respiratory disorders (OR 1.31), psychiatric disorders (1.37), reproductive disorders (OR 1.54), and eye disorders (OR 1.55). The factors associated with systemic reactogenicity were mostly comparable, but there were differences for comorbidities, drug use, and the strength of the regression coefficient.

Conclusions

This extensive study with over 22,000 vaccine recipients in the Netherlands demonstrated that, taken into account all factors in the model, the Comirnaty® vaccine gave the least and the Vaxzevria® vaccine the most reactogenicity in general and systemic after the first dose. Also a person with a history of COVID-19 disease, female sex and younger age had an increased odds for experiencing reactogenicity after vaccination.

Rescue of infectious bursal disease virus from mosaic full-length clones composed of serotype I and II cDNA

Infectious Bursal Disease Virus (IBDV) is the causative agent of one of the most important and wide-spread infectious diseases among commercial chicken flocks. IBDV causes a depletion of B-lymphoid cells in the bursa of Fabricius, inducing immunosuppression, morbidity, or even acute mortality. Because currently used live IBDV vaccines are derivatives from field isolates no serologic discrimination between field isolates and live vaccines can be made. The recently developed reverse genetics techniques for IBDV allows one to generate genetically modified IBDVs which might have altered biological and antigenic properties. Here, we describe the rescue of mosaic serotype I IBDVs, of which the polyprotein encoding region was partly replaced by the corresponding region of a serotype II strain. A mosaic virus, containing the C-terminal part of serotype II VP3 showed only a slightly delayed release of progeny virus compared to unmodified serotype I virus, while maximum viral titers at 25 h post infection were equal. Since serotype specific epitope(s) are present in the C-terminal part of VP3, we were able to discriminate this rescued virus from serotype I and II IBDV strains. These findings make the use of a chimeric VP3 a promising approach to develop an IBDV marker vaccine.