Body-wide chimerism and mosaicism are predominant causes of naturally occurring ABO discrepancies.

Routine ABO blood group typing of apparently healthy individuals sporadically uncovers unexplained mixed-field reactions. Such blood group discrepancies can either result from a haematopoiesis-confined or body-wide dispersed chimerism or mosaicism. Taking the distinct clinical consequences of these four different possibilities into account, we explored the responsible cause in nine affected individuals. Genotype analyses revealed that more than three-quarters were chimaeras (two same-sex females, four same-sex males, one sex-mismatched male), while two were mosaics. Short tandem repeat analyses of buccal swab, hair root and nail DNA suggested a body-wide involvement in all instances. Moreover, genome-wide array analyses unveiled that in both mosaic cases the causative genetic defect was a unique copy-neutral loss of heterozygosity encompassing the entire long arm of chromosome 9. The practical transfusion- or transplantation-associated consequences of such incidental discoveries are well known and therefore easily manageable. Far less appreciated is the fact that such findings also call attention to potential problems that directly ensue from their specific genetic make-up. In case of chimerism, these are the appearance of seemingly implausible family relationships and pitfalls in forensic testing. In case of mosaicism, they concern with the necessity to delineate innocuous pre-existent or age-related from disease-predisposing and disease-indicating cell clones.

Tick-borne encephalitis virus IgG antibody surveillance: vaccination- and infection-induced seroprevalences, south-western Germany, 2021.

BackgroundThe exact epidemiology of tick-borne encephalitis virus (TBEV) infections is unknown because many TBEV infections have an influenza-like or asymptomatic course. Surveillance data are based on patients with any (predominantly neurological) symptoms that prompted diagnostic testing. Infection- and vaccine-induced antibodies against TBEV can be distinguished using an NS1 IgG ELISA.AimIn a seroprevalence study we aimed to investigate TBEV antibody prevalence, incidences, manifestation indices and potential protection rates in a highly endemic district in south-western Germany.MethodsWe analysed 2,220 samples from healthy blood donors collected between May and September 2021. The reported number of TBEV infections was provided on a sub-district level by the local public health authorities. Blood samples were first screened using a TBEV IgG ELISA. In a second step, all positive samples were further analysed with a recently established NS1 IgG ELISA. The presence of specific antibodies against TBEV (excluding cross-reacting antibodies against other flaviviruses) was confirmed by testing screening-positive samples with a microneutralisation assay.ResultsOf 2,220 included samples, 1,257 (57%) tested positive by TBEV IgG ELISA and 125 tested positive for infection-induced TBEV NS1 antibodies, resulting in a TBEV NS1 IgG seroprevalence at 5.6% in our population. The yearly incidence based on the NS1 ELISA findings resulted in 283 cases per 100,000 inhabitants.ConclusionUsing the TBEV NS1 IgG assay, we confirmed a manifestation index of ca 2% and a high incidence of predominantly silent TBEV infections (> 250/100,000/year), which exceeds the incidence of notified cases (4.7/100,000/year) considerably.

Motivation, blood donor satisfaction and intention to return during the COVID-19 pandemic.

BACKGROUND AND OBJECTIVES: This study aimed to describe motives as well as donation experiences and the intention to return for further donations of German whole blood donors who donated at the beginning of the COVID-19 pandemic. MATERIALS AND METHODS: To describe motives and donor experiences, a retrospective survey was conducted among whole blood donors that had a donation appointment at the German Red Cross Blood Donation Service in the first 4 weeks of the pandemic. A donor questionnaire including 17 retrospective questions was sent to 7500 donors. Donor motivation and donor experiences were compared for different donor groups using chi-square statistics. Finally, in an ordinal logistic regression model predictors for the intention to return were identified. RESULTS: More than half of the participating donors (56.9%) wanted to contribute to the fight against the pandemic by donating blood. Most of the donors were satisfied with their last donation experience and felt safe during the blood donor appointment. However, some donors would have liked more information on how to deal with the pandemic (20.3%). Intention to return for further donations was strongly associated with overall satisfaction (OR: 1.67, CI: 1.47-1.90) and the feeling of being safe during blood donation (OR: 1.33, CI: 1.05-1.68). CONCLUSION: Donor satisfaction with the last donation was high and the vast majority of donors felt very safe. However, those donors who felt unsafe expressed a low intention to return and blood donation services should therefore carefully monitor donor satisfaction.

Changes in the Whole Blood Donor Population in South-West Germany: 2010 versus 2016.

BACKGROUND: In the recent past, the discrepancy between blood supply and future demand may have been overestimated. As medical progress develops rapidly, it will be essential to monitor ongoing demographic changes in the donor population regularly and to re-evaluate retention and recruiting strategies. The aim of the current study was to compare first-time donor (FTD) characteristics and their return rates. We therefore compared whole blood (WB) donations in total and the annual donation frequencies in 2010 and in 2015/2016. Furthermore, we evaluated whether over the same observation period, medical reasons for deferral underwent a change (2010 vs. 2015). METHODS: The return probability of FTD within 12 months was analysed in 2010 and 2015 with respect to successful donation versus deferral and with regard to age. The total number of WB donations was investigated, and age distribution was compared between 2010, 2013 and 2016. WB donation frequencies were calculated with respect to age and gender in 2010 and 2016. In a second analysis, medical reasons for deferral were differentiated into 14 categories and a possible impact of time (2010 vs. 2015) on the respective percentage was studied. RESULTS: We observed a significant decline of the FTD return rate from 42.5% to 38.8% in donors that successfully donated WB while the rate remained unchanged in deferred FTD. At the same time the mean FTD age decreased from 29.1 ± 11.6 to 28.5 ± 11.7 years in 2016. Analysis of total WB donations revealed an increase of all donations from donors ≥60 years, a constant percentage from donors <30 years but a declining proportion of donors aged 30-59 years from 2010 to 2013 to 2016. In parallel, annual mean WB donation frequencies decreased over time. Deferrals due to travel history increased significantly from 2010 to 2015 both in FTD and repeat donors. CONCLUSION: There is ongoing demographic change in our WB donor population. Our data prove a need for a re-evaluation of retention and recruitment strategies since previous marketing campaigns seem to have neglected the age group 30-59 years. This must be addressed in further studies as this age group will be highly relevant for assuring future blood supplies since donor recruitment from adolescents will be limited due to declining birth rates. Furthermore, deferral due to travel history is increasing significantly. Thus we will require further studies on the possible impact on donor retention.

Monetary compensation and blood donor return: results of a donor survey in southwest Germany.

BACKGROUND/AIMS: The aim of this study was to compare donor return patterns of non-compensated and compensated German first-time donors to assess the effect of monetary reward on donor return. METHODS: We conducted a retrospective analysis of a donor survey of 3,077 non-compensated and 738 compensated German first-time donors. Survey data were pooled and linked with blood donor return rates within the 1st, 2nd, and 3rd year. Logistic regression models were used to estimate differences in the probability of donor return between non-compensated and compensated donors. RESULTS: In the first 2 years following the initial donation, compensated donors were more likely to return with the odds of giving at least one further donation 1.86 (1st year) and 1.32 (2nd year) times higher for compensated donors than for non-compensated donors. In the 3rd year, there were no significant differences in donor return. CONCLUSION: This report, which was based on two non-randomized donor samples, suggests that monetary compensation may increase the likelihood of donors returning in the first months after the initial donation. Monetary reward may therefore be used as a short-term strategy to recruit new donors. The long-term commitment, however, seems not to be affected by monetary reward, and complementary donor retention strategies are needed.

Donor satisfaction with a new german blood donor questionnaire and intention of the donor to return for further donations.

BACKGROUND: The aim of this study was to describe donor satisfaction regarding different aspects of the new German blood donor questionnaire (BDQ) and to assess whether donor satisfaction is associated with the intention to return for further donations. METHODS: A random number of 6,600 blood donors, donating at the German Red Cross Blood Service Baden-Wuerttemberg - Hessen, were asked to rate their satisfaction with four different aspects of the BDQ. Chi-square statistics was used to test for associations between satisfaction and the intention to return. RESULTS: Most of the donors were satisfied with format and layout (72.7%) and the clarity of the questions (72.5%). However, only 39.5% of the donors were satisfied with the scope of the BDQ and 44.3% with the questions about sexual risk behavior. The lowest satisfaction seemed to be among experienced donors and among donors from small municipalities. Among experienced and very experienced donors, a significant association between the satisfaction with the different aspects and the intention to return became apparent. CONCLUSION: When considering the implementation of the BDQ, Blood Donor Services have to weigh up the advantages of increased deferral rates among donors with high-risk behavior against the potential drop-out of dissatisfied blood donors.

Characteristics of Lapsed German Whole Blood Donors and Barriers to Return Four Years after the Initial Donation.

BACKGROUND: The aim of the study was to identify characteristics of lapsed donors 4 years after the initial donation as well as self-reported barriers to return for further blood donations. METHODS: A random number of 8,000 blood donors, donating for the German Red Cross Blood Service Baden-Württemberg - Hessen, were asked to fill in a self-administered questionnaire. The response rate was 38.5%. Donors were categorized as 'lapsed' if they had not donated within the last 24 months. The odds of being a lapsed donor were determined in a multivariate logistic regression. RESULTS: Multivariate analysis showed that lapsed donors were more likely to be female, between 26 and 33 years old, not employed, have moved, and were dissatisfied with the last donation experience. Furthermore, lapsed donors were less likely to have family members or friends who also donate blood. Medical reasons and having moved to another city were the most frequently named reasons preventing lapsed donors from continuing to donate blood. CONCLUSION: The importance of medical reasons and having moved was rated much higher than in previous studies. We conclude that barriers to return may vary considerably between countries and blood services. Therefore, donor surveys are required to guide reactivation campaigns.

Donor Deferral Rates after the Implementation of a New German Blood Donor Questionnaire.

BACKGROUND: The implementation of a new national German blood donor questionnaire was proposed to improve donor and recipient safety. METHODS: We compared deferral/exclusion rates of whole blood donors before (May 2010, n = 64,735) and after (May 2011, n = 71,687) the implementation of a new blood donor questionnaire. Considering seasonal variations, analysis was performed with respect to collection site (mobile vs. fixed), sex, donor status (first-time vs. repeat), age, and the frequencies of sexual risk behavior and other reasons for deferral. RESULTS: We observed a statistically significant increase (p < 0.001) of the overall deferral/exclusion rate from 6.2 to 8.1%, irrespective of type of collection site (fixed: from 6.0 to 8.5%; mobile: from 6.2 to 8.0%), sex (females: from 7.5 to 9.9%; males: from 5.1 to 6.6%), donor status (first-time donors: from 19.7 to 24.7%; repeat donors: from 4.6 to 6.3%) or age (18-29 years: from 9.1 to 11.7%; 60-71 years: from 5.1 to 6.6%). Confidential self-exclusion increased from 0.08 to 0.14% (p < 0.001). Besides risk behavior, various medical reasons could be identified that explain this increase. CONCLUSIONS: The new blood donor questionnaire resulted in an increased deferral/exclusion of all donor groups. Thus the impact on future blood supply must be considered carefully, and long-term studies and investigation of donor acceptance will be needed.

Common clonal origin of conventional T cells and induced regulatory T cells in breast cancer patients.

Regulatory CD4+ T cells (Treg) prevent tumor clearance by conventional T cells (Tconv) comprising a major obstacle of cancer immune-surveillance. Hitherto, the mechanisms of Treg repertoire formation in human cancers remain largely unclear. Here, we analyze Treg clonal origin in breast cancer patients using T-Cell Receptor and single-cell transcriptome sequencing. While Treg in peripheral blood and breast tumors are clonally distinct, Tconv clones, including tumor-antigen reactive effectors (Teff), are detected in both compartments. Tumor-infiltrating CD4+ cells accumulate into distinct transcriptome clusters, including early activated Tconv, uncommitted Teff, Th1 Teff, suppressive Treg and pro-tumorigenic Treg. Trajectory analysis suggests early activated Tconv differentiation either into Th1 Teff or into suppressive and pro-tumorigenic Treg. Importantly, Tconv, activated Tconv and Treg share highly-expanded clones contributing up to 65% of intratumoral Treg. Here we show that Treg in human breast cancer may considerably stem from antigen-experienced Tconv converting into secondary induced Treg through intratumoral activation.

The Mannheim Cord Blood Bank: Experiences and Perspectives for the Future.

SUMMARY: BACKGROUND AND METHODS: As a source of hematopoietic stem cells, cord blood (CB) is an alternative to bone marrow or peripheral blood stem cells (PBSC). The Mannheim Cord Blood Bank has currently stored about 1,750 allogeneic CB units. Here we report our experiences and discuss future perspectives of CB banking. We analyzed CB units for nucleated cell (NC), mononucleated cell (MNC) and CD34+ cell count, volume, colony-forming units (CFU-GM) as well as ethnic background of the donor. Transplanted CB units were analyzed for patient and transplant characteristics and compared to stored CB units. RESULTS: Only 25% of all collected CB units met storage criteria. Main reasons for exclusion were: i) insufficient volume (57.7%), ii) delayed arrival at the processing site (19.2%) and iii) little cell count (7.2%). Up to now 36 CB units have been released for transplantation mainly to children (62%). Transplant indications were hematological diseases, immune deficiencies and metabolic diseases. Transplanted CB units showed significantly higher cell counts compared to stored units (NC: 12.5 vs. 7.2 x 10(8), MNC: 4.7 vs. 2.9 x 10(8), CD34+ cells: 3.3 vs. 1.8 x 10(6), mean; p < 0.001 each) and were found more often in ethnic minority groups (36 vs. 20%; p = 0.04). CONCLUSIONS: Even though cell count and volume are key parameters for the eligibility of CB units, our data indicate that the ethnic background of the donor also plays a major role. Collection and processing of CB should be optimized in order to gain maximum volume and cell counts.

Rapid screening of granulocyte antibodies with a novel assay: flow cytometric granulocyte immunofluorescence test.

BACKGROUND: White blood cell (WBC)-associated antibodies can lead to severe pulmonary transfusion reactions (transfusion-related acute lung injury [TRALI]). Investigation of a large number of blood donor samples using the standard granulocyte immunofluorescence test (GIFT) and granulocyte agglutination test (GAT) proved to be difficult to perform due to the time-consuming process and the large quantity of test cells required. This study describes the novel flow cytometric GIFT (Flow-GIFT) method for a rapid detection of granulocyte antibodies by flow cytometric analysis. STUDY DESIGN AND METHODS: A total of 141 sera were analyzed for the presence of granulocyte antibodies that were previously associated with suspected TRALI. As test cells whole blood samples from human neutrophil antigen (HNA)-typed donors were isolated using cell sedimentation in a ficoll density gradient. WBCs were incubated with the respective serum and binding of antibodies to the test cells was detected using fluorescein isothiocyanate-conjugated anti-human antibody. Standard GIFT and GAT were performed as reference methods. RESULTS: Seven sera containing anti-HNA-3a, CD16, and HLA Class I were negative in the standard GIFT and eight sera containing anti-HNA-2a, anti-CD16, and anti-HLA Class I were not detected in the GAT. The novel Flow-GIFT was able to detect all granulocyte antibodies, which were only detectable in a combination of standard GIFT and GAT. In serial dilution tests, the Flow-GIFT detected the antibodies at higher dilutions than the reference methods GIFT and GAT. CONCLUSION: The Flow-GIFT method permits rapid detection of granulocyte antibodies requiring fewer donor test cells. This method is ideal for automation and will potentially open the way for screening of granulocyte antibodies in a large donor population.

Anti-HLA antibodies and pulmonary valve allograft function after the Ross procedure.

BACKGROUND AND AIM OF THE STUDY: Rejection is a plausible cause of failure of allograft valves, but has not been demonstrated unequivocally in humans. A cross-sectional study has been conducted on the frequency of anti-human leukocyte antigen (HLA) antibodies in order to identify any correlation with allograft function in adult patients, following the Ross procedure. METHODS: Anti-HLA antibodies were determined during regular follow up (median 1.1 years postoperatively) in a random sample of 197 patients (151 males, 46 females; mean age 46 +/- 13 years). Panel-reactive antibodies (PRA) were determined by cytotoxicity testing; anti-HLA class 2 antibodies (HLA2AB) were determined by ELISA in a subgroup of 94 patients. Echocardiographic examinations were performed during the first visit and at a median of 6.8 years postoperatively. RESULTS: The prevalence of positive antibody tests was 47% for PRA and 52% for HLA2AB. A slight deterioration of allograft valve function occurred between the two examinations (median maximal pressure gradient increased from 9 mmHg to 13 mmHg, p < 0.001; median degree of regurgitation increased from zero to trivial, p = 0.020). The degree of regurgitation was slightly, but significantly, higher in PRA-positive patients at both examinations (p = 0.008 and p = 0.038). No relationship was observed between PRA status and pressure gradients, nor between HLA2AB status and allograft valve function. Neither were any other risk factors for allograft valve deterioration identified. CONCLUSION: Subtle, clinically irrelevant and temporally stable differences with regard to regurgitation across the allograft were observed between PRA-positive and -negative patients. These findings neither proved nor disproved rejection, but rather suggested that a slow deterioration of allograft valve function was complex, and most likely multifactorial.

Laparoscopy in patients over 60 years old: a prospective, randomized evaluation of laparoscopic versus open adnexectomy.

OBJECTIVE: To compare objective and subjective parameters of surgical stress following laparoscopic and open adnexectomy in patients older than 60 years old. STUDY DESIGN: Twenty patients with a benign ovarian tumour were prospectively randomized to undergo adnexectomy by a laparoscopic or an open surgical procedure. Measurements included C-reactive protein; interleukin-6 before, during, and after surgery; intensity and duration of postoperative pain; and complications and recovery period. Statistical analysis consisted of analysis of variance and a Mann-Whitney U test. RESULTS: The levels of the interleukin-6 and C-reactive protein differed significantly between the 2 operative procedures (P = .013) in favor of the laparoscopic approach. The laparoscopic approach was associated with a reduction in operative morbidity, postoperative pain, analgesic requirement, and recovery period. CONCLUSIONS: Minimally invasive surgery is of particular benefit to elderly patients if there is a plan in place for appropriate staging and treatment by laparotomy for malignancy. It should be the first choice and may help to reduce postoperative complications.

Individual variability in cyclosporin A sensitivity: the assessment of functional measures on CD28-mediated costimulation of human whole blood T lymphocytes.

The quantitative analysis of cyclosporin A (CsA) effects might be helpful for optimizing immunosuppressive treatment after allogeneic organ transplantation in individual patients, as rejection can occur despite the existence of CsA blood levels within therapeutic ranges. Previous investigations found that costimulation of the CD28 pathway generally mediates CsA-resistant proliferation of T cell receptor (TCR)-activated T lymphocytes. However, here we describe considerable interindividual variation regarding the immunosuppressive effects of CsA (1000 microg/L) on anti-CD3/CD28 T cell costimulation in a human whole blood assay. In the in vitro study, we found a significant reduction of T cell proliferation, activation marker expression (CD25, CD69) on the T cell surface, and interleukin-2 (IL-2) protein expression in whole blood samples of all healthy subjects (n = 11). However, the investigation of cytokine mRNA profiles revealed variable results of in vitro CsA sensitivity. Whole blood samples of 3 of 11 healthy individuals demonstrated a marked suppression of IL-2 mRNA expression (>50%) and a partial inhibition of IL-4, interferon-gamma (IFN-gamma), and tumor necrosis factor-alpha (TNF-alpha) mRNA expression on addition of CsA. In contrast, the remaining 8 healthy individuals had cytokine mRNA expression levels that were unaffected or even increased when CsA was administered in vitro. In patients undergoing CsA monotherapy (ex vivo study, n = 9), we found a significant suppression of IL-2 mRNA levels in 4 of 9 patients ex vivo. Thus, we cannot confirm a universal CsA resistance of T cells on anti-CD3/CD28 costimulation. Instead, our results suggest an individual degree of CsA sensitivity that might be more consistent with clinical experience. Prospective studies are necessary to determine if individual degrees of CsA sensitivity correlate with clinical events and are associated with a low or high risk of transplant rejection.

Evaluation of the decellularized pulmonary valve homograft (SynerGraft).

BACKGROUND AND AIM OF THE STUDY: Rejection is thought to contribute to the degeneration of valved homografts. A novel cryopreserved decellularized homograft valve (SynerGraft; CryoLife, Inc.) offers the unique opportunity to gain new insight into the immunology of homograft implantation and its significance for valve function. METHODS: Twenty-four patients (group I; mean age 37 +/- 11 years) underwent implantation of a pulmonary SynerGraft and were examined at one and six months postoperatively; 22 patients (group II; mean age 41 +/- 17 years) with conventional homografts served as controls. Temperature, C-reactive protein (CRP) levels and white blood cell count (WBC) were studied perioperatively. Follow up included echocardiography and anti-human leukocyte antigen (HLA) class I antibody determination. RESULTS: Significantly lower temperatures were measured in group I (p = 0.019). CRP level and WBC each increased postoperatively, but did not differ between groups. During follow up, none of the SynerGraft patients became positive for anti-HLA antibodies, compared with 66% of controls (p = 0.011). Homograft diameter and valve orifice area were decreased significantly at one month after surgery in groups I and II (25 +/- 1 versus 18 +/- 3 mm; 25 +/- 1 versus 19 +/- 2 mm, respectively; p <0.001 both groups). Transvalvular pressure gradients significantly increased during follow up. CONCLUSION: Implantation of the SynerGraft pulmonary homograft appeared safe, and though evidence was found of a reduced immunologic response after SynerGraft implantation this (unexpectedly) did not translate into any hemodynamic advantage. Hence, factors other than rejection appear as the main contributions to the observed functional changes.

The interleukin-6 promoter (-597/-572/-174)genotype does not affect interleukin-6 production in hemodialysis patients.

Kidney transplant recipients with the interleukin-6 (IL-6) GGG/GGG promoter (-597/-572/-174)genotype were shown to have a better long-term outcome. Further, the same (-597/-572/-174)genotype was found to be associated with less IL-6 production in healthy control subjects. To verify this observation in potential kidney transplant recipients, IL-6 production was analyzed in 85/142 hemodialysis patients. We could not confirm an impaired IL-6 secretion in carriers of the GGG/GGG (-597/-572/-174)genotype and propose a significantly lower IL-6 production in hemodialysis patients versus healthy control subjects to explain this. However, we suggest subsequent studies of IL-6 production in kidney allograft recipients to further elucidate the pathophysiological relevance of IL-6 for transplant outcome.

Optimized PCR with sequence specific primers (PCR-SSP) for fast and efficient determination of Interleukin-6 Promoter -597/-572/-174Haplotypes.

BACKGROUND: Interleukin-6 (IL-6) promoter polymorphisms at positions -597(G-->A), -572(G-->C) and -174(G-->C) were shown to have a clinical impact on different major diseases. At present PCR-SSP protocols for IL-6 -597/-572/-174haplotyping are elaborate and require large amounts of genomic DNA. FINDINGS: We describe an improved typing technique requiring a decreased number of PCR-reactions and a reduced PCR-runtime due to optimized PCR-conditions. CONCLUSION: This enables a fast and efficient determination of IL-6 -597/-572/-174haplotypes in clinical diagnosis and further evaluation of IL-6 promoter polymorphisms in larger patient cohorts.

The pharmacodynamic effect of sirolimus: individual variation of cytokine mRNA expression profiles in human whole blood samples.

Sirolimus (SRL) has become an important alternative to calcineurin inhibitors due to its unique mechanism of action. Since rejection and poor graft outcome are still frequent problems despite therapeutic-range blood concentrations, pharmacodynamic measurements of its immunosuppressive effects would be of great clinical value to optimize treatment in individual patients. We performed a human whole blood assay using real time cytokine RT-PCR for the pharmacodynamic assessment of SRL. IL-2, IL-4 and IL-6 mRNA levels were quantitatively determined upon T-cell-specific stimulation in healthy individuals (n=11; in vitro) and in kidney-transplant patients (n=3; ex vivo). Furthermore, IL-2 protein secretion and T-cell proliferation was measured. After 24h incubation we observed a stronger suppression of IL-2 and IL-4 mRNA expression upon SRL addition (p<0.005; p<0.005) versus 4h (p<0.05; p<0.05). SRL effects displayed a remarkable interindividual variation, which proved to be independent of the concentration applied. Notably, 3/11 and 2/11 individuals had unaffected IL-2 and IL-4 mRNA expression after 4h incubation with SRL, respectively. In contrast, a general suppression of IL-2 protein secretion and T-cell proliferation was induced. Analysis of kidney-transplant patients verified interindividual variation and proved comparability of in vitro and ex vivo effects. We describe an individual degree of SRL-sensitivity that may correlate with clinical efficacy. Rather than analysis of one single peak, we suggest determination of two absolute cytokine mRNA peak levels for the pharmacodynamic assessment of SRL. However, prospective clinical studies are necessary to determine whether individual degrees of SRL-sensitivity correlate with clinical outcome.

Immunomodulatory effects of Sanglifehrin A in the innate and acquired immune response of neonatal whole blood cells.

Previous investigations have shown the immunosuppressive activity of the immunophilin-binding macrolide Sanglifehrin A (SFA). In adults, SFA also exerts anti-inflammatory properties in lipopolysaccharide (LPS)-stimulated whole blood cultures. It was the aim of this study to investigate whether the unique properties of SFA are also present in the neonatal immune system, as neonates are susceptible to serious infection due to an immaturity of immune responses. We used a whole blood assay to investigate the impact of SFA on T-cell proliferation and secretion of T-cell cytokines upon Anti-CD3/Anti-CD28 costimulation. In addition, interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-alpha) secretion was assessed in whole blood monocytes after LPS stimulation. Furthermore, the influence of SFA on LPS-induced signal transduction pathways, specifically the activity of p42/44, p38 and Ap-1, was assessed in neonatal PBMCs. Neonatal cord blood lymphocytes were found to have a diminished IL-4, IL-6, TNF-alpha and interferon-gamma (IFN-gamma) production upon Anti-CD3/Anti-CD28 costimulation compared to adult whole blood lymphocytes. In contrast, no significant differences were noted for either IL-2 production or proliferation of CD4+ cells. Upon addition of 1000nM SFA to neonatal whole blood cultures, a significant inhibition of both, T-cell cytokine secretion and proliferation was demonstrated. In line with data from adult whole blood cultures, SFA proved to be a strong inhibitor of LPS-induced expression of IL-6 and TNF-alpha in the neonatal whole blood system. In signal transduction studies of the LPS pathway, a potent inhibition of the protein kinase p42/44 was demonstrated. SFA was also shown to block nuclear translocation of the transcription factor Ap-1. SFA was proved to have inhibitory effects on innate and acquired immune response of neonatal whole blood cells. The protein kinase p42/44 and the transcription factor Ap-1 were demonstrated to be potential key molecules for the anti-inflammatory effect of SFA.