Humoral and Cellular Immune Responses of People Living With Human Immunodeficiency Virus After 3 Doses of Messenger RNA BNT162b2 Severe Acute Respiratory Syndrome Coronavirus 2 Vaccine: A Prospective Cohort Study

Background

Recent studies have shown good serological and cellular immune responses in people living with human immunodeficiency virus (PLWH) after receipt of 2 doses of messenger RNAA (mRNA) severe acute respiratory syndrome coronavirus 2 vaccine. Data are missing regarding the response after 3 vaccine doses.

Methods

We followed up a group of PLWH who received 3 doses of the mRNA BNT162b2 vaccine and for whom data of humoral immune response after 2 vaccine doses were available. Patients provided a blood sample 4-6 months after the booster dose. The aim of the study was to measure the serological and cellular response after the third dose and to evaluate factors associated with the vaccine response.

Results

Fifty patients have provided a serum sample for serological evaluation after the booster. The anti-receptor-binding domain (RBD) immunoglobulin (Ig) G titers were higher after the booster with a median delta of 3240 arbitrary units/mL. The median CD4+ T-cell count was 660/μL (interquartile range, 515-958/μL) and had no influence on the antibody level. Factors associated with lower delta included higher CD8+ T-cell count (P = .02) and longer time between the third dose and the blood test (P = .01). Higher anti-RBD IgG titer after the second vaccine (P = .03), as well as a longer interval between second and third doses (P = .031) were associated with higher delta. There was no increase in the median number of activated interferon γ+ and tumor necrosis factor α+ CD4+ T cells after the booster (n = 8).

Conclusions

The anti-RBD IgG level after 3 doses of mRNA BNT162b2 vaccine was higher than the level after 2 doses, suggesting additional value of the booster. Cellular response did not further increase after a booster.

Clinically Complex LRBA Deficiency Due to a Founder Allele in the Georgian Jewish Population

Pathogenic variants in LRBA, encoding the LPS Responsive Beige-Like Anchor (LRBA) protein, are responsible for recessive, early-onset hypogammaglobulinemia, severe multi-organ autoimmunity, and lymphoproliferation, with increased risk for malignancy. LRBA deficiency has a wide clinical spectrum with variable age of onset and disease severity. Three apparently unrelated patients with LRBA deficiency, of Georgian Jewish descent, were homozygous for LRBA c.6640C > T, p.R2214*, leading to a stop upstream of the LRBA BEACH domain. Despite carrying the same LRBA genotype, the three patients differed in clinical course: the first patient was asymptomatic until age 25 years; the second presented with failure to thrive at age 3 months; and the third presented at age 7 years with immune cytopenias and severe infections. Two of the patients developed malignancies: the first patient was diagnosed with recurrent Hodgkin's disease at age 36 years, and the second patient developed aggressive gastric cancer at age 15 years. Among Georgian Jews, the carrier frequency of the LRBA p.R2214* allele was 1.6% (4 of 236 Georgian Jewish controls). The allele was absent from other populations. Haplotype analysis showed a shared origin of the mutation. These three patients revealed a pathogenic LRBA founder allele in the Georgian Jewish population, support the diverse and complex clinical spectrum of LRBA deficiency, and support the possibility that LRBA deficiency predisposes to malignancy.

Dominant-negative signal transducer and activator of transcription (STAT)3 variants in adult patients: A single center experience

Background

Autosomal dominant hyper-IgE syndrome (AD-HIES) caused by dominant negative (DN) variants in the signal transducer and activator of transcription 3 gene (STAT3) is characterized by recurrent Staphylococcal abscesses, severe eczema, chronic mucocutaneous candidiasis (CMC), and non-immunological facial and skeletal features.

Objectives

To describe our experience with the diagnosis and treatment of adult patients with AD-HIES induced by DN-STAT3 variants.

Methods

The medical records of adult patients (>18 years) treated at the Allergy and Clinical Immunology Clinic of Hadassah Medical Center, Jerusalem, Israel, were retrospectively analyzed. Immune and genetic workups were used to confirm diagnosis.

Results

Three adult patients (2 males; age 29-41 years) were diagnosed with DN-STAT3 variants. All patients had non-immunological features, including coarse faces and osteopenia. Serious bacterial infections were noted in all patients, including recurrent abscesses, recurrent pneumonia, and bronchiectasis. CMC and diffuse dermatophytosis were noted in two patients. Two patients had severe atopic dermatitis refractory to topical steroids and phototherapy. Immune workup revealed elevated IgE in three patients and eosinophilia in two patients. Whole exome sequencing revealed DN-STAT3 variants (c.1166C>T; p.Thr389Ile in two patients and c.1268G>A; p. Arg423Gln in one patient). Variants were located in DNA-binding domain (DBD) and did not hamper STAT3 phosphorylation Treatment included antimicrobial prophylaxis with trimethoprim/sulfamethoxazole (n=2) and amoxycillin-clavulanic acid (n=1), and anti-fungal treatment with fluconazole (n=2) and voriconazole (n=1). Two patients who had severe atopic dermatitis, were treated with dupilumab with complete resolution of their rash. No adverse responses were noted in the dupilumab-treated patients.

Discussion

Dupilumab can be used safely as a biotherapy for atopic dermatitis in these patients as it can effectively alleviate eczema-related symptoms. Immunologists and dermatologists treating AD-HIES adult patients should be aware of demodicosis as a possible manifestation. DN-STAT3 variants in DBD do not hamper STAT3 phosphorylation.

Immunogenicity induced by two and three doses of the BNT162b2 mRNA vaccine in patients with autoimmune inflammatory rheumatic diseases and immunocompetent controls: a longitudinal multicentre study

OBJECTIVES

To evaluate long-term kinetics of the BNT162b2 mRNA vaccine-induced immune response in adult patients with autoimmune inflammatory rheumatic diseases (AIIRD) and immunocompetent controls.

METHODS

A prospective multicentre study investigated serum anti-SARS-CoV-2 S1/S2 IgG titre at 2-6 weeks (AIIRD n=720, controls n=122) and 6 months (AIIRD n=628, controls n=116) after the second vaccine, and 2-6 weeks after the third vaccine dose (AIIRD n=169, controls n=45). T-cell immune response to the third vaccine was evaluated in a small sample.

RESULTS

The two-dose vaccine regimen induced a higher humoral response in controls compared with patients, postvaccination seropositivity rates of 100% versus 84.72%, p<0.0001, and 96.55% versus 74.26%, p<0.0001 at 2-6 weeks and at 6 months, respectively. The third vaccine dose restored the seropositive response in all controls and 80.47% of patients with AIIRD, p=0.0028. All patients treated with methotrexate monotherapy, anticytokine biologics, abatacept and janus kinase (JAK) inhibitors regained the humoral response after the third vaccine, compared with only a third of patients treated with rituximab, entailing a 16.1-fold risk for a negative humoral response, p≤0.0001. Cellular immune response in rituximab-treated patients was preserved before and after the third vaccine and was similar to controls. Breakthrough COVID-19 rate during the Delta surge was similar in patients and controls, 1.83% versus 1.43%, p=1.

CONCLUSIONS

The two-dose BNTb262 regimen was associated with similar clinical efficacy and similar waning of the humoral response over 6 months among patients with AIIRD and controls. The third vaccine dose restored the humoral response in all of the controls and the majority of patients.

Humoral Response to the Third Dose of Sars-Cov-2 Vaccine in Kidney Transplant Recipients

BACKGROUND

Most solid organ transplant recipients did not develop an appreciable serologic response after 2 doses of the mRNA SARS-CoV-2 vaccine.

METHODS

We analyzed the humoral response after a third dose of the BNT162b2 vaccine in 130 kidney transplant recipients, compared to 48 health care workers, and associated factors, including prevaccine cellular immune response, by evaluating intracellular cytokine production after stimulation of donor's peripheral blood mononuclear cells.

RESULTS

After 2 doses, most of the controls (47 out of 48, 98%) and only 40% of kidney recipients (52 of 130) kidney recipients were seropositive (P < .001). Most seronegative recipients developed a serologic response after the booster (47 out 78, 60%), thus bringing the total number of seropositive recipients to 99 out of 130 (76%). After the third dose, there was a significant increase in antibodies titers in both groups. Decreased humoral response was significantly associated with an older age, lower lymphocyte count, and a lower level of antibodies before booster administration. CD4+TNFα+ and CD4+INFγ+ were correlated with mean increase in antibody titers.

CONCLUSIONS

A third dose of the BNT162b2 mRNA vaccine in kidney recipients is safe and effectively results in increased IgG anti-S levels, including in individuals who were seronegative after 2 doses. Long-term studies of the length of the immune response and protection are required.

OP0177 IMMUNOGENICITY INDUCED BY TWO AND THREE DOSES OF THE BNT162B2 mRNA VACCINE IN PATIENTS WITH AUTOIMMUNE INFLAMMATORY RHEUMATIC DISEASES AND IMMUNOCOMPETENT CONTROLS: A LONGITUDINAL MULTI-CENTER STUDY

Background

Data on the kinetics of the immune response to SARS-CoV-2 vaccination in patients with autoimmune inflammatory rheumatic diseases (AIIRD) are limited.

Objectives

To evaluate the kinetics of the immune response induced by two and three doses of the BNT162b2 mRNA vaccine in adult patients with AIIRD and immunocompetent controls.

Methods

A prospective multicenter study investigated the antibody response to the BNT162b2 vaccine by serial measurement of serum anti-SARS-CoV-2 S1/S2 IgG titers at the following time points: 2-6 weeks (AIIRD n=720, controls n=122) and six months (AIIRD n=628, controls=116) after the second vaccine dose, and 2-6 weeks after the third vaccine dose (AIIRD n=169, controls n=45). A seropositive response was defined as a detectable anti-S1/S2 IgG titer ≥ 15 BAU/ml. T-cell immune response was evaluated in a sample of patients (n=28) and controls (n=9) by intracellular staining of S-stimulated CD4+ T-cells for TNFα and IFNγ production.

Results

The two-dose vaccine regimen induced a higher humoral response in controls compared to patients, as reflected by the post-vaccination seropositivity rates of 100% vs 84.72%, p<0.0001, and 96.55% vs 74.26%, p<0.0001 at 2-to-6 weeks and at 6 months, respectively. The decline of S1/S2 IgG titers within six months was similar in controls and patients. Following the 3rd vaccine, the seropositivity rate increased to 80.47% and 100% in AIIRD and control groups, p=0.0028, with a significantly higher increase of S1/S2 IgG titers in controls compared with AIIRD patients, 284.09±76.58 vs 219.39±151.55 BAU/ml, p=0.0016. At all-time points, S1/S2 IgG titers were significantly lower in AIIRD patients compared with controls (Figure 1).

We further investigated the impact of therapies on the vaccine‘s immunogenicity (Figure 1). Glucocorticoids (GC) were associated with a significantly lower seropositivity rate and lower S1/S2 IgG titers compared to controls at all time points. Monotherapy with methotrexate (MTX) was associated with a comparable to controls humoral response at all time points. Anti-cytokine biologics (TNFi, IL6i, IL17i) were associated with an initial high seropositivity rate, similar to controls, followed by a steeper decline at 6 months, 79.82% vs 96.55%, p=0.0001, and restoration of seropositivity after the 3rd vaccine dose in all patients. JAKi were associated with a mildly decreased seropositivity rate after the 2nd vaccine dose and similar to controls response after the 3rd vaccine dose. Abatacept was associated with a reduced immunogenicity after the 2nd vaccine dose, but was restored to 100% seropositivity after the 3rd vaccine dose. Rituximab (RTX) significantly blunted the humoral response at all time points, with a seropositivity rate of 42% after the 2nd vaccine dose, 29% at 6 months, and with increase to 40% after the 3rd vaccine dose. A third of the RTX-treated patients who were seronegative after two vaccine doses, seroconverted after the 3rd dose. The multivariate model for predicting the seropositive response to vaccination found that higher S1/S2 IgG titers after the 2nd vaccine dose was associated with a higher seropositivity rate following the 3rd vaccine dose, OR 1.026 (1.008-1.045), p=0.0027, and that treatment with RTX was associated with a 14.3-fold risk for a negative humoral response, p≤0.0001. Cellular immune response, evaluated mainly in RTX treated patients, was preserved prior to and after the 3rd vaccine dose and was similar to controls.

Conclusion

Over a six-month period, the two dose BNTb262 vaccination was associated with a similar extent of waning of the humoral immune response in AIIRD patients and controls. The 3rd vaccine dose restored the response in all controls and in patients treated with MTX monotherapy, anti-cytokine biologics, abatacept, and JAKi. Treatment with GC and RTX was associated with an impaired humoral response at all time points.

Acknowledgements

We would like to thank the statistician Mr Yishai Friedlander and Mr Yoram Neufeld for their valuable assistance.

Disclosure of Interests

None declared

SARS-CoV-2 Humoral and Cellular Immune Responses of Patients With HIV After Vaccination With BNT162b2 mRNA COVID-19 Vaccine in the Tel-Aviv Medical Center

Background

Little is known about vaccine efficacy and sustainability among people with HIV (PWH). We estimated humoral and cellular immune responses postvaccination with BNT162b2 mRNA coronavirus disease 2019 (COVID-19) vaccine among PWH in Tel-Aviv Medical Center.

Methods

The vaccine humoral response was evaluated by measuring immunoglobulin G (IgG) titers of antispike receptor-binding domain antibodies (anti-RBD IgG). Cellular response was assessed by stimulating donor peripheral blood mononuclear cells with pooled complete S-peptide mix.

Results

One hundred thirty-six PWH who completed 2 doses of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine were tested for anti-RBD IgG and compared with 61 vaccinated health care workers (HCWs). The antibody titers were similar between the groups (median, 118 BAU/mL for PWH and 101.4 BAU/mL for HCWs; P = .231), although the mean time from second vaccine was 4.5 months in PWH and 6.7 months in HCWs (P < .0001). Longer time from second vaccine dose was associated with decreased antibody level, as were CD4 counts <300 cells/µL compared with higher CD4 counts (25.1 BAU/mL vs 119.3 BAU/mL, respectively; P = .047). There was no difference in cellular immune response between vaccinated PWH, convalescent unvaccinated PWH, and vaccinated HCWs.

Conclusions

The humoral immune response of PWH was comparable to that of HCWs after BNT162b2 mRNA vaccination. Cellular immune response did not differ between vaccinated PWH, convalescent PWH, and vaccinated HCWs. PWH with CD4 counts <300 cells/µL (n = 9) had lower antibody titers compared with patients with counts >300 cells/µL (n = 127).

Immunogenicity of a third dose of the BNT162b2 mRNA Covid-19 Vaccine in Patients with impaired B cell reconstitution after cellular therapy - a Single Center Prospective Cohort Study

Patients with delayed B-cell reconstitution/B-cell aplasia after cellular therapy show decreased immunogenicity to the BNT162b2 mRNA COVID-19 vaccine. We prospectively evaluated both humoral and cellular immune response to a third vaccine dose in patients after allogeneic HCT (n = 10) or CD19-based chimeric antigen receptor T cells (CAR-T) therapy (n = 6) with low absolute B cell numbers and who failed to mount a humeral response after 2 vaccine doses. Humoral response was documented in 40% and 17% after allogeneic HCT and CAR-T therapy, respectively. None of the patients with complete B-cell aplasia developed anti-vaccine antibodies. Cellular response was documented in all patients after allogeneic HCT and in 83% of the patients after CAR-T. T-cell subclasses levels were not predictive for response, while a longer duration from infusion of cells was associated with a better cellular response. We conclude that cellular response develops with repeated vaccine doses even in patients with B-cell aplasia or delayed B-cell reconstitution, and these patients should therefore be vaccinated. These results should be considered in future studies analyzing immunogenicity in this population. Larger and longer follow-up studies are required to confirm whether cellular immunogenicity translates into vaccine efficacy.

Safety and Immunogenicity of the BNT162b2 mRNA COVID-19 Vaccine in Patients after Allogeneic HCT or CD19-based CART therapy-A Single-Center Prospective Cohort Study

Data are scarce regarding both the safety and immunogenicity of the BNT162b2 mRNA COVID-19 vaccine in patients undergoing immune cell therapy; thus, we prospectively evaluated these two domains in patients receiving this vaccine after allogeneic hematopoietic cell transplantation (HCT; n = 66) or after CD19-based chimeric antigen receptor T cell (CART) therapy (n = 14). Overall, the vaccine was well tolerated, with mild non-hematologic vaccine-reported adverse events in a minority of the patients. Twelve percent of the patients after the first dose and 10% of the patients after the second dose developed cytopenia, and there were three cases of graft-versus-host disease exacerbation after each dose. A single case of impending graft rejection was summarized as possibly related. Evaluation of immunogenicity showed that 57% of patients after CART infusion and 75% patients after allogeneic HCT had evidence of humoral and/or cellular response to the vaccine. The Cox regression model indicated that longer time from infusion of cells, female sex, and higher CD19⁺ cells were associated with a positive humoral response, whereas a higher CD4⁺/CD8⁺ ratio was correlated with a positive cellular response, as confirmed by the ELISpot test. We conclude that the BNT162b2 mRNA COVID-19 vaccine has impressive immunogenicity in patients after allogeneic HCT or CART. Adverse events were mostly mild and transient, but some significant hematologic events were observed; hence, patients should be closely monitored.

Immunogenicity of Pfizer-BioNTech COVID-19 vaccine in patients with inborn errors of immunity

Background

In mid-December 2020, Israel started a nationwide mass vaccination campaign against coronavirus disease 2019 (COVID-19). In the first few weeks, medical personnel, elderly citizens, and patients with chronic diseases were prioritized. As such, patients with primary and secondary immunodeficiencies were encouraged to receive the vaccine. Although the efficacy of RNA-based COVID-19 vaccines has been demonstrated in the general population, little is known about their efficacy and safety in patients with inborn errors of immunity (IEI).

Objective

Our aim was to evaluate the humoral and cellular immune response to COVID-19 vaccine in a cohort of patients with IEI.

Methods

A total of 26 adult patients were enrolled, and plasma and peripheral blood mononuclear cells were collected from them 2 weeks following the second dose of Pfizer-BioNTech COVID-19 vaccine. Humoral response was evaluated by testing anti–SARS-CoV-2 spike (S) receptor-binding domain and antinucleocapsid antibody titers and evaluating neutralizing ability by inhibition of receptor-binding domain–angiotensin-converting enzyme 2 binding. Cellular immune response was evaluated by using ELISpot, estimating IL-2 and IFN-γ secretion in response to pooled SARS-CoV-2 S- or M-peptides.

Results

Our cohort included 18 patients with a predominantly antibody deficiency, 2 with combined immunodeficiency, 3 with immune dysregulation, and 3 with other genetically defined diagnoses. Twenty-two of them were receiving immunoglobulin replacement therapy. Of the 26 patients, 18 developed specific antibody response, and 19 showed S-peptide–specific T-cell response. None of the patients reported significant adverse events.

Conclusion

Vaccinating patients with IEI is safe, and most patients were able to develop vaccine-specific antibody response, S-protein–specific cellular response, or both.

Anti-CD19 CAR-T therapy for EBV-negative posttransplantation lymphoproliferative disease-a single center case series

Posttransplantation lymphoproliferative disease (PTLD) is a potentially fatal disorder arising after solid organ or hematopoietic cell transplantation. Survival rates of PTLD with diffuse large B-cell lymphoma (DLBCL) phenotype have improved due to the introduction of rituximab, however, reports on curative management of refractory PTLD are scarce. Here, we describe successful management of three patients with refractory EBV-negative PTLD with chimeric antigen receptor T-cell (CAR-T) therapy. All patients continued calcineurin inhibitors throughout the whole course of treatment. T-cell immunophenotyping was performed on both the apheresed cells and CAR-T product to investigate the T-cell compartment subpopulations. All three patients responded to a single infusion of tisagenlecleucel and two of them achieved CR. Toxicity profile was similar to other patients with non-PTLD DLBCL treated with CAR-T. No transplanted graft dysfunction was observed during the course of therapy. To our knowledge, this is the first report demonstrating that patients with EBV-negative refractory PTLD may benefit from CAR-T therapy, similarly to other patients with relapse/refractory DLBCL. A larger cohort of patients is needed to further establish proof-of-concept.

Monogenic Inflammatory Bowel Disease: It's Never Too Late to Make a Diagnosis

Background: More than 50 different monogenic disorders have been identified as directly causing inflammatory bowel diseases, typically manifesting in the first years of life. We present the clinical course and immunological work-up of an adult patient who presented in adolescent years with an atypical gastrointestinal phenotype and was diagnosed more than two decades later with a monogenic disorder with important therapeutic implications.

Methods: Whole exome sequencing was performed in a 37-years-old patient with a history of diarrhea since adolescence. Sanger sequencing was used to validate the suspected variant. Mass cytometry (CyTOF) and flow cytometry were conducted on peripheral blood mononuclear cells for deep immunophenotyping. Next-generation sequencing of the TCRB and IgH was performed for global immune repertoire analysis of circulating lymphocytes.

Results: We identified a novel deleterious c.1455C>A (p.Y485X) mutation in LRBA. CyTOF studies demonstrated significant changes in immune landscape in the LRBA-deficient patient, including an increase in myeloid derived suppressor cells and double-negative T cells, decreased B cells, low ratio of naïve:memory T cells, and reduced capacity of T cells to secrete various cytokines following stimulation, including tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ). In addition, this patient exhibited low frequency of regulatory T cells, with a reduction in their CTLA4 expression and interleukin (IL)-10 secretion. Finally, we show marked oligoclonal expansion of specific B- and T-cell clones in the peripheral blood of the LRBA-deficient patient.

Conclusions: LRBA deficiency is characterized by marked immunological changes in innate and adaptive immune cells. This case highlights the importance of advanced genetic studies in patients with a unique phenotype, regardless of their age at presentation.

Process evaluation of five tailored programs to improve the implementation of evidence-based recommendations for chronic conditions in primary care

Background

Although there is evidence that tailored implementation strategies can be effective, there is little evidence on which methods of tailoring improve the effect. We designed and evaluated five tailored programs (TPs) each consisting of various strategies. The aim of this study was to examine (a) how determinants of practice prioritized in the design phase of the TPs were perceived by health care professionals who had been exposed to the TPs and whether they suggested other important determinants of practice and (b) how professionals used the offered strategies and whether they suggested other strategies that might have been more effective.

Methods

We conducted a mixed-method process evaluation linked to five cluster-randomized trials carried out in five European countries to implement recommendations for five chronic conditions in primary care settings. The five TPs used a total of 28 strategies which aimed to address 38 determinants of practice. Interviews of professionals in the intervention groups and a survey of professionals in the intervention and control groups were performed. Data collection was conducted by each research team in the respective national language. The interview data were first analyzed inductively by each research team, and subsequently, a meta-synthesis was conducted. The survey was analyzed descriptively.

Results

We conducted 71 interviews; 125 professionals completed the survey. The survey showed that 76 % (n = 29) of targeted determinants of practice were perceived as relevant and 95 % (n = 36) as being modified by the implementation interventions by 66 to 100 % of professionals. On average, 47 % of professionals reported using the strategies and 51 % considered them helpful, albeit with substantial variance between countries and strategies. In the interviews, 89 determinants of practice were identified, of which 70 % (n = 62) had been identified and 45 % (n = 40) had been prioritized in the design phase. The interviewees suggested 65 additional strategies, of which 54 % (n = 35) had been identified and 20 % (n = 13) had been prioritized, but not selected in the final programs.

Conclusions

This study largely confirmed the perceived relevance of the targeted determinants of practice. This contrasts with the fact that no impact of the trials on the implementation of the recommendations could be observed. The findings suggest that better methods for prioritization of determinants and strategies are needed.

Trial registration

Each of the five trials was registered separately in recognized trial registries. Details are given in the respective trial outcome papers.

Electronic supplementary material

The online version of this article (doi:10.1186/s13012-016-0473-8) contains supplementary material, which is available to authorized users.

Comparison of indirect CsI/a:Si and direct a: SE digital radiography: An assessment of contrast and detail visualization

Purpose: To assess and quantify the image quality at two dose levels for an amorphous Silicon (a:Si) Cesium Iodide (CsI) flat panel system compared with a direct amorphous Selenium (a:Se) digital radiography system.

Material and Methods: A contrast detectability test was performed employing the CDRAD-phantom at mAs-values leading to approximately equal phantom entrance doses of 41.4, 57.9, 75.1 and 120.8 µGy for the a:Se and 39.9, 58.4, 75.6 and 117.9 µGy for the CsI system. Images were presented to 4 independent observers. For quantitative comparison, the image quality figure (IQF) was calculated. Statistical analysis was performed using Pearson's correlation and the Wilcoxon test. A ROC-analysis was performed employing the TRG-phantom in a high- and a low-dose setting leading to entrance doses of 126.2 and 35 µGy for the direct, and 125.9 and 34.4 µGy for the indirect system. Statistical significance was evaluated using the Wilcoxon test

Results: The flat panel a:Si digital system provided superior results compared with the a:Se drum digital system with respect to low-dose settings for CDRAD-phantom and ROC-analysis, ensuring a better image quality with respect to contrast and detail detectability. Higher-dose settings provided similar results for both systems.

Conclusion: Image quality of a:Si flat panel digital radiography proved to be superior to a:Se drum digital radiography using low-dose settings. If the primary target is dose reduction indirect flat panel technology should be used.

[Challenges and potentials of primary care in a multicultural society]

The greatest proportion of basic health care for patients with a migrational background living in Germany is provided by general practitioners. There is evidence that patients with a migrational background see a general practitioner as a gate keeper in case of physical or mental complaints even more frequently than the native German population. In contrast, the impact of migration-specific tasks in general practice appears to be relatively low in the medical and public discourse. This article analyzes the current situation of medical care for migrant patients in general practice and shows its potential to offer low-threshold high quality health care services to migrant patients and the whole population. In addition, an overview on migration-specific issues in research, teaching, and continuous medical education of general practitioners is provided. Finally, the implications of these findings for future research questions on migration-sensitive interventions are discussed.

[Health screening and vaccination status--results from a patient survey in German general practices]

The vaccination status of German adults needs improvement. Low participation is also known in health screening programmes like the "Check up 35" which is offered every two years for adults aged 35 or above. However, the number of participants in health screening increases with age whereas vaccination status decreases. Within a study about patients' attitudes towards prevention in primary care, we investigated the knowledge about the vaccination status. Therefore, an anonymous survey was conducted among 333 patients from five general practices in 2007. 76% of the potential participants in health screening declared that they utilise it at least infrequently. In contrast to those who participate frequently in health screening (67%), those who participate infrequently (38%) or never (33%) but declare that their vaccination status is complete are significantly rare. Due to the results of our study it has to be discussed whether the health screening "Check up 35" should be regularly accompanied with vaccination counselling.

BCG priming of dendritic cells enhances T regulatory and Th1 function and suppresses allergen-induced Th2 function in vitro and in vivo

BACKGROUND

The inverse correlation of mycobacterial infection with asthma prevalence and the inhibitory effects of vaccination with Bacille Calmette-Guérin (BCG) on airway hyperreactivity in asthma models suggest modulation of dendritic cell (DC) and T cell functions by mycobacterial compounds.

METHODS

To delineate these immunological effects, the immunogenicity of BCG Copenhagen, BCG Chicago and BCG Pasteur was compared in a mouse model. Bone marrow-derived dendritic cells (BMDCs) from BALB/c mice were stimulated with ovalbumin (OVA) with or without BCG. BMDCs were phenotypically characterized by flow cytometry, and we used ELISA to measure the cytokine production of BMDCs as well as of co-cultivated allergen-specific T cells in response to OVA-pulsed. Immunomodulatory effects of BCG were studied in a model of allergic airway inflammation by adoptive transfer of allergen-pulsed BMDCs.

RESULTS

Immunomodulation with BCG induced production of IL-10 and IL-12 by BMDCs. Co-cultured allergen-specific T cells produced less IL-5, IL-13 and IFN-gamma but more IL-10. Also the number of FoxP3(+) regulatory T cells was enhanced. Strongest effects were seen with BCG Chicago and BCG Pasteur. In vivo, administration of BCG modulated OVA-pulsed BMDCs then reduced eosinophilic airway inflammation but enhanced infiltration with granulocytes. Airway hyperreactivity and mucus production were reduced and more FoxP3(+) T cells were observed.

CONCLUSION

BCG-induced suppression of Th2-type allergic airway inflammation was associated with enhancement of regulatory T cell function but also of Th1-associated neutrophilic airway inflammation. These findings raise concerns regarding the safety profile of BCG as a potential tool for prevention and therapy of allergic airway disease.

Quantitative proton magnetic resonance spectroscopy of the normal liver and malignant hepatic lesions at 3.0 Tesla

This comparative study of tumour patients and volunteers aimed at differentiating liver parenchyma from neoplastic lesions by using localised (1)H MRS at 3.0 T as an adjunct to MRI. In total 186 single-voxel proton spectra of the liver were acquired at 3.0 T using the body transmit receive coil. Consecutive stacks of breath-hold spectra were acquired in the PRESS technique at a short echo time of 35 ms and a repetition time of 2,000 ms. Processing of the spectra included spectral alignment with the software package SAGE and quantitative processing with LCModel. The resulting metabolite concentrations were presented in arbitrary units relative to the internal water. In general, the spectra showed four main groups of resonances originating from the methyl protons (0.8-1.1 ppm) and methylene protons of the lipids (1.1-1.5 ppm; 2.0-2.2 ppm) as well as the methyl protons of choline-containing compounds (CCC) at 3.2 ppm. Overall, the CCC and lipid values in malignant liver tumours showed no significant differences to liver parenchyma. On average, total lipid measurements in normal liver parenchyma increased with age, while those of the CCC did not show pertinent changes. Significant differences between the contents of CCC in malignant liver tumours and normal liver parenchyma were not observed, because in patients and volunteers normal liver tissue showed a large variability in the content of CCC.

MR-guided interstitial laser thermotherapy of colorectal liver metastases: efficiency, safety and patient survival

PURPOSE

Evaluation of MR-guided interstitial laser thermotherapy (ILT) of colorectal liver metastases under consideration of efficacy, safety and patient survival.

MATERIALS AND METHODS

Sixty-six inoperable patients with a total of 117 colorectal liver metastases were treated with MR-guided laser therapy in 96 sessions. 40.9% of patients presented metastases from rectum carcinoma, 30.3% from sigmoid carcinoma and 28.8% from colon carcinoma. Inclusion criteria were < or =5 metastases < or =5 cm in greatest diameter and no extrahepatic tumor spread. Internally water-cooled 9F power-laser-applicators were placed under CT-fluoroscopy. For MR-guided ILT, a 1064 nm Nd-YAG-lasers with a beam divider with multi applicator technique was used. The energy applied was 10 watt per centimeter diffusor length, with the diffusor length ranging from 20 to 40 mm. The mean duration of the energy application was 23 minutes (range: 15 - 37 minutes). The endpoint of the laser ablation was defined as the absence of hyperintense tumor tissue in the continuously monitored T2-w fat saturated gradient-echo sequences. Follow-up included contrast-enhanced MRI using T1- and T2-weighted spin-echo and gradient-echo sequences every three months after treatment. Survival times were calculated using the Kaplan-Meier method.

RESULTS

The median follow-up was 8.7 months (mean 11.8; standard deviation 9.9; range 1 to 36). The overall median progression free survival was 6.1 months (range, 0.3 to 27+ months). Median survival was 23 months (95% CI, 17-29 months). The rate of major complications was 2.1% (n = 2) and peri-procedural mortality (30 days) was 3% (n = 2). After 3, 6, 9, and 12 months, local tumor control was 98.3%, 91.4%, 76.1%, and 69.4%, respectively. In no patient metastatic deposits along the catheter access route were found.

CONCLUSIONS

In patients with colorectal liver metastases, interstitial laser thermotherapy is an effective and safe therapeutic option and therefore suitable not only in palliative situations.

Colon dissection: a new three-dimensional reconstruction tool for computed tomography colonography

PURPOSE

To improve the sensitivity of computed tomography (CT) colonography in the detection of polyps by comparing the 3D reconstruction tool "colon dissection" and endoluminal view (virtual colonoscopy) with axial 2D reconstructions.

MATERIAL AND METHODS

Forty-eight patients (22 M, 26 F, mean age 57 +/- 21) were studied after intra-anal air insufflation in the supine and prone positions using a 16-slice helical CT (16 x 0.625 mm, pitch 1.7; detector rotation time 0.5 s; 160 mAs und 120 kV) and conventional colonoscopy. Two radiologists blinded to the results of the conventional colonoscopy analyzed the 3D reconstruction in virtual-endoscopy mode, in colon-dissection mode, and axial 2D slices.

RESULTS

Conventional colonoscopy revealed a total of 35 polyps in 15 patients; 33 polyps were disclosed by CT methods. Sensitivity and specificity for detecting colon polyps were 94% and 94%, respectively, when using the "colon dissection", 89% and 94% when using "virtual endoscopy", and 62% and 100% when using axial 2D reconstruction. Sensitivity in relation to the diameter of colon polyps with "colon dissection", "virtual colonoscopy", and axial 2D-slices was: polyps with a diameter >5.0 mm, 100%, 100%, and 71%, respectively; polyps with a diameter of between 3 and 4.9 mm, 92%, 85%, and 46%; and polyps with a diameter < 3 mm, 89%, 78%, and 56%. The difference between "virtual endoscopy" and "colon dissection" in diagnosing polyps up to 4.9 mm in diameter was statistically significant.

CONCLUSION

3D reconstruction software "colon dissection" improves sensitivity of CT colonography compared with the endoluminal view.

Effect of dose on image quality in a detector-based dual-exposure, dual-energy system for chest radiography

PURPOSE

To assess the image quality of subtracted soft tissue and bone images of a CsI-detector-based dual-energy system for chest radiography at varying dose levels.

MATERIAL AND METHODS

We evaluated a CsI-detector-based, dual-exposure, dual-energy prototype system; 126 patients were categorized into groups of small, medium, and large. Fixed values were applied for mAs and mA. The patients were randomized into two groups with intended higher and lower speed pairs of approximately 400/1000 (high and low energy shot) and 200/500, respectively. True speed equivalents were calculated retrospectively using the detector dose. Image quality was evaluated by two highly experienced radiologists in consensus applying a rating scale of 1 to 5 for quality indicators such as image noise, residual bone structures, motion artifacts, and others.

RESULTS

Significantly decreased noise and a significant improvement for display of bone details in the bone image were noted with the higher dose, whereas a significant increase in motion artifacts reduced image quality at the higher dose.

CONCLUSION

Radiation dose did not significantly influence the perception of dual-energy image quality. Dual-energy subtraction, as described, has the potential to become a future routine application in chest radiography.

Comparison of indirect CsI/a:Si and direct a:Se digital radiography. An assessment of contrast and detail visualization

PURPOSE

To assess and quantify the image quality at two dose levels for an amorphous Silicon (a:Si) Cesium Iodide (CsI) flat panel system compared with a direct amorphous Selenium (a:Se) digital radiography system.

MATERIAL AND METHODS

A contrast detectability test was performed employing the CDRAD-phantom at mAs-values leading to approximately equal phantom entrance doses of 41.4, 57.9, 75.1 and 120.8 micro Gy for the a:Se and 39.9, 58.4, 75.6 and 117.9 micro Gy for the CsI system. Images were presented to 4 independent observers. For quantitative comparison, the image quality figure (IQF) was calculated. Statistical analysis was performed using Pearson's correlation and the Wilcoxon test. A ROC-analysis was performed employing the TRG-phantom in a high- and a low-dose setting leading to entrance doses of 126.2 and 35 micro Gy for the direct, and 125.9 and 34.4 micro Gy for the indirect system. Statistical significance was evaluated using the Wilcoxon test.

RESULTS

The flat panel a:Si digital system provided superior results compared with the a:Se drum digital system with respect to low-dose settings for CDRAD-phantom and ROC-analysis, ensuring a better image quality with respect to contrast and detail detectability. Higher-dose settings provided similar results for both systems.

CONCLUSION

Image quality of a:Si flat panel digital radiography proved to be superior to a:Se drum digital radiography using low-dose settings. If the primary target is dose reduction indirect flat panel technology should be used.

GABAergic cells are the major postsynaptic targets of mossy fibers in the rat hippocampus

Dentate granule cells communicate with their postsynaptic targets by three distinct terminal types. These include the large mossy terminals, filopodial extensions of the mossy terminals, and smaller en passant synaptic varicosities. We examined the postsynaptic targets of mossy fibers by combining in vivo intracellular labeling of granule cells, immunocytochemistry, and electron microscopy. Single granule cells formed large, complex "mossy" synapses on 11-15 CA3 pyramidal cells and 7-12 hilar mossy cells. In contrast, GABAergic interneurons, identified with immunostaining for substance P-receptor, parvalbumin, and mGluR1a-receptor, were selectively innervated by very thin (filopodial) extensions of the mossy terminals and by small en passant boutons in both the hilar and CA3 regions. These terminals formed single, often perforated, asymmetric synapses on the cell bodies, dendrites, and spines of GABAergic interneurons. The number of filopodial extensions and small terminals was 10 times larger than the number of mossy terminals. These findings show that in contrast to cortical pyramidal neurons, (1) granule cells developed distinct types of terminals to affect interneurons and pyramidal cells and (2) they innervated more inhibitory than excitatory cells. These findings may explain the physiological observations that increased activity of granule cells suppresses the overall excitability of the CA3 recurrent system and may form the structural basis of the target-dependent regulation of glutamate release in the mossy fiber system.

Excitatory synaptic connections onto rat hippocampal inhibitory cells may involve a single transmitter release site

1. Whole-cell tight-seal records of excitatory postsynaptic currents (EPSCs) were made from inhibitory cells in the CA3 region of thin hippocampal slices. We tested the hypothesis that excitatory synaptic connections made on inhibitory cells involve few transmitter release sites. 2. EPSCs impinging on inhibitory cells had a time to peak of 0.4-3.8 ms and an amplitude of 8-90 pA at a holding potential of -60 mV. They were suppressed by the excitatory amino acid antagonists 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) and DL-2-amino-5-phosphonovaleric acid (APV). 3. Addition of tetrodotoxin (TTX) and Co2+ to the external solution reduced the frequency of EPSCs from 0.90 to 0.25 s-1 (n = 24 cells). In the majority of cells EPSC amplitude distributions were not significantly changed. 4. Increasing Ca2+ and reducing Mg2+ in the external solution, in order to enhance the probability of transmitter release, did not change EPSC amplitude distributions. In contrast, amplitude histograms for IPSCs recorded from pyramidal cells were shifted to higher mean values in this solution. 5. EPSCs were elicited in inhibitory cells by electrical stimulation via a glass pipette placed near to pyramidal cells in stratum pyramidale. EPSCs elicited by weak stimuli had similar amplitude distributions to excitatory synaptic events recorded in the presence of TTX and Co2+. 6. These findings suggest excitatory synaptic connections made with CA3 inhibitory cells involve few or possibly just one transmitter release site.

Relative functional buffering capacity in 400-meter runners, long-distance runners and untrained individuals

Buffering is a factor which influences performance in short and middle-term endurance by compensating exercise acidosis. The aim of the study was to establish whether respiration parameters are a relative measure of buffering capacity and to study the influence of buffering on specific performance parameters. Three groups (each of ten subjects) with defined degrees of adaptation [untrained (UT), aerobic-trained (AeT) and elite 400-m runners (AnT) with a best time of 48.47 +/- 0.98 s] were examined in an incremental multi-stage test on the treadmill. Breath-by-breath gas analysis was performed using mass spectrometry and computer routines. Serum lactate concentrations were determined at each exercise level until subjective exhaustion. A value for the relative functional buffering capacity (relFB) was calculated using exercise metabolic parameters. Running speed at the lactate threshold was used as the starting point of buffering. The start of respiratory compensation of acidosis (RCP) was taken as the endpoint of buffering. RCP was determined at the point of decrease in end-tidal CO2 content (CO2-ET). RelFB was given in percent of buffering to running speed at RCP. Group AnT attained the same maximum performance data (maximum running speed, maximum rate of O2 consumption) as group AeT. However, these values were attained in group AnT with a significantly higher relFB (AnT: 31.0 +/- 3.2% vs. AeT: 15.7 +/- 3.9%, P < 0.0001), while a higher lactate threshold indicated a greater oxidative capacity in AeT (AeT: 3.07 +/- 0.26 m.s-1 vs. AnT: 2.68 +/- 0.22 m.s-1).(ABSTRACT TRUNCATED AT 250 WORDS)

Stimulation in vitro by 1,25-dihydroxy-vitamin D3 of intestinal cell calcium uptake and calcium-binding protein

Treatment of duodenal tissue from rats deficient in vitamin D with 1,25-dihydroxy-vitamin D3 [1,25-(OH)2-D3] led to more than a doubling of calcium uptake by the isolated cells and the appearacne in those cells of previously undetectable calcium-binding protein (CaBP). Treatment with the precursor, 25-hydroxy-vitamin D3, was without effect on calcium uptake or CaBP. Cells from vitamin D-replete animals took up three and a half times more calcium than cells from deficient animals. This rapid (90-minute) effect of in vitro treatment with a physiological dose (4.7 X 10(-8)M) of 1,25-(OH)2-D is the first such report and is in accord with the regulatory role of the hormone-like sterol.

Intestinal CaBP: a new quantitive index of vitamin D deficiency in the rat

Rats raised from weaning on regiments adequate in calcium and phosphorus but deficient in vitamin D will have no detectable intestinal calcium-binding proteins (CaBP), whether or not they show other signs of vitamin D deficiency, such as hypocalcemia. When hypocalcemic, vitamin D-deficient animals were treated with 25-hydroxycholecalciferol, a vitamin D metabolite, they showed a dose-dependent increase in plasma calcium and CaBP; both responses can be described by a single linear relationship, which appears to apply whether the metabolite is 25-hydroxycholecalciferol or dihydrotachysterol. Since vitamin D status is only one determinant of plasma calcium, whereas CaBP (or its expression) appears to depend on vitamin D quantitatively, CaBP may be used as an index of vitamin D status, provided calcium intake is controlled.

Regulation of intestinal calcium-binding protein calcium intake in the rat

Analytical gel electrophoresis of the vitamin D-dependent intestinal calcium-binding protein (CaBP) has demonstrated two protein bands (1 and 2) of similar molecular weight and similar specific binding activity. The mucosal concentration of CaBP, measured by a quantitative competitive binding assay, has been shown to vary reproducibly and inversely with calcium intake and the mucosal calcium concentration. These same factors also influence the relationship of bands 1 and 2. When animals on a high-calcium diet were placed on a low-calcium diet, their CaBP increased by 35% in 24 h and by 48% in 48 h and reached a level typical of animals on a low-calcium diet. Measurement of the diurnal variation of CaBP and mucosal calcium in animals allowed access to feed only at night revealed significant, but inverse, oscillations. These observations are interpreted as reflecting a regulation of CaBP by the mucosal calcium concentration, which appears to reflect absorbed calcium in transit.

-Crystallin. The isolation and characterization of distinct macromolecular fractions

alpha-Crystallin was isolated from calf lens periphery by chromatography on DEAE-cellulose and gel filtration. Three distinct populations of macromolecules have been isolated with molecular weights in the ranges approx. 6x10(5)-9x10(5), 0.9x10(6)-4x10(6) and greater than 10x10(6). The concentration of macromolecules at the molecular-weight limits of a population are very low. The members of the different populations do not appear to be in equilibrium with each other. Further, in those molecular-weight fractions investigated, no equilibrium between members of the same population was observed. The population of lowest molecular weight comprises 65-75% of the total material. The amino acid and subunit composition of the different-sized fractions appear very similar, if not identical. The only chemical difference observed between the fractions is the presence of significant amounts of sugar in the higher-molecular-weight fractions. Subunit molecular weights of approx. 19.5x10(3) and 22.5x10(3) were observed for all alpha-crystallin fractions.