A new blood group antigen is defined by anti-CD59, detected in a CD59-deficient patient

BACKGROUND

CD59 is a cell surface glycoprotein of approximately 20 kDa limiting the lytic activity of the terminal complement complex C5b-9. Although CD59 is known as a red blood cell (RBC) antigen defined by monoclonal antibodies, it so far has not been identified as a blood group antigen, since the description of a human alloantibody was missing. In this study we show the presence of an anti-CD59 in a patient affected by a homozygous CD59 deficiency.

STUDY DESIGN AND METHODS

RBC CD59 and CD55 were determined by flow cytometry or by the column agglutination technique using monoclonal antisera. Commercially available His-tagged recombinant soluble CD59 protein was used to inhibit anti-CD59.

RESULTS

Seven cases of an isolated CD59 deficiency due to three distinct null alleles of the CD59 gene have been published so far. Recently we described the CD59-null allele c.146delA in a young child of heterozygous parents. Her plasma contained an alloantibody directed against the high-prevalence RBC antigen CD59. The antibody specificity was identified using soluble recombinant human CD59 protein, which blocked the reactivity of the patient's antibody and of monoclonal anti-CD59 but not of monoclonal anti-CD55. In addition, RBC alloantibodies such as anti-K, anti-C, anti-c, or anti-Fy(a) remained unaffected. Therefore, inhibition by recombinant CD59 is a useful diagnostic tool to detect alloantibodies in the presence of anti-CD59.

CONCLUSION

This is the first demonstration of a human anti-CD59 alloantibody, which defines CD59 as an RBC blood group antigen. CD59 represents a candidate for a new blood group system.

HLA class II haplotypes differentiate between the adult autoimmune polyglandular syndrome types II and III

BACKGROUND

Genetics of the adult autoimmune polyglandular syndrome (APS) is poorly understood.

AIM

The aim of this study was to gain further insight into the genetics of the adult APS types. SITE: The study was conducted at a university referral center.

METHODS

The human leukocyte antigen (HLA) class II alleles, haplotypes, and genotypes were determined in a large cohort of patients with APS, autoimmune thyroid disease (AITD), and type 1 diabetes and in healthy controls by the consistent application of high-resolution typing at a four-digit level.

RESULTS

Comparison of the allele and haplotype frequencies significantly discriminated patients with APS vs AITD and controls. The HLA class II alleles DRB1*03:01 *04:01, DQA1*03:01, *05:01, DQB1*02:01, and *03:02 were observed more frequently (P<.001) in APS than in AITD and controls, whereas the alleles DRB1*15:01, DQB1*03:01, and *06:02 were underrepresented in APS vs AITD (Pc<.001) and controls (Pc<.01), respectively. The DRB1*03:01-DQA1*05:01-DQB1*02:01 (DR3-DQ2) and DRB1*04:01-DQA1*03:01:DQB1*03:02 (DRB1*04:01-DQ8) haplotypes were overrepresented in APS (Pc<.001). Combination of both haplotypes to a genotype was highly prevalent in APS vs AITD and controls (Pc<.001). Dividing the APS collective into those with Addison's disease (APS type II) and those without Addison's disease but including type 1 diabetes and AITD (APS type III) demonstrated DR3-DQ2/DRB1*04:01-DQ8 as a susceptibility genotype in APS III (Pc<.001), whereas the DR3-DQ2/DRB1*04:04-DQ8 genotype correlated with APS II (Pc<.001). The haplotypes DRB1*11:01-DQA1*05:05-DQB1*03:01 and DRB1*15:01-DQA1*01:02-DQB1*06:02 are protective in APS III but not in type II (Pc<.01).

CONCLUSIONS

HLA class II haplotypes differentiate between the adult APS types II and III. Susceptible haplotypes favor the development of polyglandular autoimmunity in patients with AITD.

The complement-mediated prozone effect in the Luminex single-antigen bead assay and its impact on HLA antibody determination in patient sera

The Luminex xMAP system has become an important tool for HLA antibody screening and identification in sera of transplant patients. Recently, the Luminex single antigen bead assay was shown to be prone to an artefact, the so called prozone phenomenon: Sera with high titer HLA antibodies gave negative results when tested neat, but reacted strongly positive after 1:10 dilution. We also observed such a phenomenon and found that it was most likely caused by the complement component 1 (C1) by competitively displacing the detection antibodies. In this article we review the complement-mediated prozone effect and other mechanisms of interference with solid phase assays, and we discuss possible consequences for HLA antibody testing with the Luminex SAB assay.

Outcomes of surveillance for contralateral breast cancer in patients less than age 60 at the time of initial diagnosis

BACKGROUND

After an initial diagnosis of breast cancer, the risk of contralateral breast cancer is approximately 0.5% per year. Annual mammography is recommended to identify local recurrences and contralateral new primaries. Because the sensitivity of mammography tends to be lower in younger women, we conducted a retrospective review of the method of detection and pathologic stage of metachronous contralateral primary breast cancers according to age at diagnosis in a cohort of breast cancer patients.

METHODS

The Henrietta Banting Database contains information on cases of breast cancer diagnosed at Women's College Hospital from 1987 to 2004. From among 1992 women in the database, 71 patients were identified who were initially diagnosed before age 60 and who subsequently developed a contralateral breast cancer. Medical records were obtained for 53 of the 71 patients.

RESULTS

Of the 53 contralateral cancers, 33 (62%) were detected by mammography, including 4 in 16 patients (25%) diagnosed before age 50 and 29 in 37 patients (78%) diagnosed at age 50 or older (p ≤ 0.001).

CONCLUSIONS

Mammography has poor sensitivity for the surveillance of contralateral breast cancer in early-onset breast cancer patients. Other imaging modalities should be evaluated in this setting.

Autoimmune polyglandular syndrome type 2 shows the same HLA class II pattern as type 1 diabetes

Autoimmune polyglandular syndrome (APS) type 2 is defined by the manifestation of at least two autoimmune endocrine diseases. Only few data exist on genetic associations of APS type 2. In this controlled study, 98 patients with APS type 2, 96 patients with type 1 diabetes (T1D), and 92 patients with autoimmune thyroid disease, both as a single autoimmune endocrinopathy, were tested for association with alleles of the human leukocyte antigen (HLA) class II loci DRB1, DQA1, and DQB1. Patients with APS type 2 had significantly more often the alleles DRB1*03 (P(c) < 0.0001), DRB1*04 (P(c) < 0.000005), DQA1*03 (P(c) < 0.0001), and DQB1*02 (P(c) < 0.05), when compared with controls. Less frequent in APS were DRB1*15 (P(c) < 0.05), DQA1*01 (P(c) < 0.0005), and DQB1*05 (P(c) < 0.005). With regard to frequency and linkage of these alleles, the susceptible haplotypes DRB1*0301-DQA1*0501-DQB1*0201 and DRB1*0401/04-DQA1*0301-DQB1*0302 were deduced. Protective haplotypes in this study were DRB1*1501-DQA1*0102-DQB1*0602 and DRB1*0101-DQA1*0101-DQB1*0501. Comparing APS patients with vs without AD, no significant differences regarding HLA class II alleles were noted in our collective. Patients with T1D as a singular disease had the same susceptible and protective HLA alleles and haplotypes. The prevalence of DRB1*03 and DRB1*04 in APS patients was not because of the presence of diabetes, as the APS type 2 patients without diabetes had the same allele distribution. In conclusion, these data suggest a common immunogenetic pathomechanism for T1D and APS type 2, which might be different from the immunogenetic pathomechanism of other autoimmune endocrine disease.

Abstract P6-06-01: Relationship between Vitamin D Deficiency and Breast Cancer Histology: A Retrospective Database Review

Background: Vitamin D deficiency has recently been shown to be correlated with high rates of developing breast cancer (Chen P et al, Breast Cancer Res Treat; Oct 2009). However, the association between the degree of vitamin D deficiency and specific histological subtypes of breast cancer remains unclear. Preclinical data has suggested that vitamin D plays an essential role in the terminal differentiation of breast cancer cells, and thus vitamin D deficiency would be associated with the pathogenesis of estrogen receptor negative tumors (Welsh J et al, Journal of Steroid Biochem Mol Biol; Feb 2003), in particular triple-negative tumors, which are associated with a particularly aggressive clinical course. Methods: Beginning in July 2008, the majority of newly diagnosed breast cancer patients at University of Maryland Greenebaum Cancer Center had Vitamin D 25-OH levels testedon initial presentation to the clinic. We conducted a retrospective chart review to obtain information about tumor histology and vitamin D levels in these patients. Results: We include data on 71 patients who presented with newly-diagnosed breast carcinoma or DCIS between June 2008 and December 2009. Average age at diagnosis was 57 (range 36-87), and 58% of patients were African American. Stage distribution of the cohort included; DCIS-3%, stage I-15%, stage II-41%, stage III-28%, and stage IV-10%. Overall, 80% of the patients were vitamin D deficient at diagnosis, with vitamin D levels under 30 ng/ml, and 57% had levels under 20 ng/ml. Patients with triple-negative tumors were the most likely to be vitamin D deficient at diagnosis (90%) compared to hormone receptor-positive patients (75%), and they had the lowest mean and median vitamin D levels compared to all other patients.

Percentage of patients with Vitamin D deficiency

Vitamin D level by histological subtype

Hormone receptor-positive patients were significantly more likely to have normal vitamin D levels at diagnosis and significantly less likely to have severe deficiency (level &lt;10 ng/ml) than those with hormone receptor-negative tumors (p=0.037). African-American women in this cohort were also more likely to be severely vitamin D deficient, with levels &lt;10 ng/ml, than were Caucasian women (34% vs. 7%, p=0.048). Conclusion: Vitamin D deficiency is common among patients with newly-diagnosed breast cancer. Patients with triple-negative tumors may have a higher likelihood of being vitamin D deficient than patients with other histological subtypes.

Sensitivity of surveillance mammography for contralateral breast cancers and ipsilateral recurrences in survivors under 50

11009

Background: Annual mammography is currently the gold standard for surveillance of breast cancer survivors for both ipsilateral recurrence and contralateral new primaries. The risk of either of these events occurring has been found to be inversely proportional to age and is at least 1% per year if breast cancer was diagnosed before age 50. (Chen et al 1999) (Komoike et al 2006). However, the sensitivity of screening mammography is significantly lower in young women. We therefore sought to determine the effectiveness of surveillance mammography according to age of diagnosis using a prospective database. Methods: The Henrietta Banting Database prospectively follows all new cases of operable breast cancer diagnosed from 1987 - 2004 at Women’s College Hospital. From the 1992 women in the database, we selected all patients diagnosed before age 60 who subsequently developed non-metastatic contralateral cancers (n=71 ) or ipsilateral recurrences (n=11 ). Records were obtainable for 59 of these 82 patients. Results: Method of detection and stage of diagnosis are listed in table below for the 59 patients according to age of diagnosis of second cancers. Overall, mammography was less effective at detecting contralateral and recurrent breast cancers in younger women, detecting only 24% of these cancers in women under 50 compared to 74% in patients 50 and older (Chi-Square, p<0.001). In addition, 77% of patients under 50 whose second cancers were detected by methods other than mammography had negative surveillance mammograms in the 15 months prior to diagnosis. Conclusion: Since mammography detected only 24% of second primary breast cancers/ recurrences in survivors < age 50 and almost one third of all detected cancers were locally advanced, more sensitive imaging modalities such as breast MRI should be considered for surveillance of young survivors.

[Table: see text]

No significant financial relationships to disclose.

Effect of serum and CTL on focal growth of human cytomegalovirus

BACKGROUND

In immunocompromised patients only cytotoxic T-lymphocytes (CTL) but not antiviral antibodies appear to be efficient in control of human cytomegalovirus (HCMV) infection. This is contrasted by the well-documented neutralising activity of patient sera against standard HCMV strains.

OBJECTIVE

We tested the hypothesis that a cell-culture model based on a recent clinical HCMV isolate would more accurately approximate the clinical situation and provide an explanation for the failure of neutralising antibodies in efficient restriction of HCMV infection.

METHODS

Sera from five bone marrow transplant recipients with or without prolonged HCMV replication were analysed by an enzyme-linked immunoassay for their capacity to neutralise cell-free HCMV preparations. The inhibitory effect of these sera on viral cell-to-cell-spread was then quantified by focus expansion assays using a recent clinical HCMV-isolate and was finally compared to the inhibitory effect of HCMV-specific CTL lines.

RESULTS

Prolonged HCMV replication occurred in three patients despite high titres of neutralising antibodies. In contrast to the strong inhibitory effect on cell-free HCMV, their sera could not inhibit the focal growth of a recent cell-associated HCMV isolate, whereas CTL clones directed against pUL123 or pUL83 of HCMV effectively limited focal expansion of the clinical isolate in fibroblast culture.

CONCLUSIONS

Focus expansion assays based on a cell-associated clinical HCMV isolate provide a model for the in vivo effectiveness of virus-specific CTL and neutralising antibodies. Our data support the assumption that due to their strict cell-association clinical HCMV strains are withdrawn from neutralising antibodies.

Macrophage cultures are susceptible to lytic productive infection by endothelial-cell-propagated human cytomegalovirus strains and present viral IE1 protein to CD4+ T cells despite late downregulation of MHC class II molecules

The contribution of CD4(+) T cells to control of human cytomegalovirus (HCMV) has been shown and infected tissue macrophages might contribute to this response by antigen presentation. As shown previously, CD4(+) T cells recognize HCMV immediate-early antigen IE1 on glioblastoma cells manipulated to express MHC class II molecules. Here, the possible interference of virus-induced MHC class II downmodulation with the presentation of IE1 by natural target cells was analysed. The capacity of IE1-specific CD4(+) T-cell clones to recognize HCMV-infected monocyte-derived macrophages was tested. Various HCMV strains were used to achieve efficient infection of macrophages. Activation of CD4(+) T cells by infected macrophages was evaluated at different time points after infection. Endothelial-cell-adapted HCMV strains efficiently infected cultured human macrophages. However, the immediate-early and early phases of replication were prolonged. Infected cells entered the late replication phase only after 3 days of infection, which was associated with downmodulation of MHC class II molecules at the surface of infected cells. Strong stimulation of IE1-specific CD4(+) T cells resulted from endogenous de novo antigen production and presentation by infected macrophages during the first 3 days of virus replication, despite MHC class II downmodulation in the late replication phase. Therefore, infected macrophages are assumed to contribute to the antiviral immune response in infected organs.

Effect of Vibrio parahaemolyticus haemolysin on human erythrocytes

Haemolysin Kanagawa, a toxin from Vibrio parahaemolyticus, is known to trigger haemolysis. Flux studies indicated that haemolysin forms a cation channel. In the present study, channel properties were elucidated by patch clamp and functional significance of ion fluxes by fluorescence-activated cell sorting (FACS) analysis. Treatment of human erythrocytes with 1 U ml-1 haemolysin within minutes induces a non-selective cation permeability. Moreover, haemolysin activates clotrimazole-sensitive K+ channels, pointing to stimulation of Ca2+-sensitive Gardos channels. Haemolysin (1 U ml-1) leads within 5 min to slight cell shrinkage, which is reversed in Ca2+-free saline. Erythrocytes treated with haemolysin (0.1 U ml-1) do not undergo significant haemolysis within the first 60 min. Replacement of extracellular Na+ with NMDG+ leads to slight cell shrinkage, which is potentiated by 0.1 U ml-1 haemolysin. According to annexin binding, treatment of erythrocytes with 0.1 U ml-1 haemolysin leads within 30 min to breakdown of phosphatidylserine asymmetry of the cell membrane, a typical feature of erythrocyte apoptosis. The annexin binding is significantly blunted at increased extracellular K+ concentrations and by K+ channel blocker clotrimazole. In conclusion, haemolysin Kanagawa induces cation permeability and activates endogenous Gardos K+ channels. Consequences include breakdown of phosphatidylserine asymmetry, which depends at least partially on cellular loss of K+.

Transplantation of a combination of CD133+ and CD34+ selected progenitor cells from alternative donors

Positive selected haematopoietic stem cells are increasingly used for allogeneic transplantation with the CD34 antigen employed in most separation techniques. However, the recently described pentaspan molecule CD133 appears to be a marker of more primitive haematopoietic progenitors. Here we report our experience with a new CD133-based selection method in 10 paediatric patients with matched unrelated (n = 2) or mismatched-related donors (n = 8). These patients received a combination of stem cells (median = 29.3 x 10(6)/kg), selected with either anti-CD34 or anti-CD133 coated microbeads. The proportion of CD133+ selected cells was gradually increased from patient to patient from 10% to 100%. Comparison of CD133+ and CD34+ separation procedures revealed similar purity and recovery of target populations but a lower depletion of T cells by CD133+ selection (3.7 log vs. 4.1 log, P < 0.001). Both separation procedures produced >90% CD34+/CD133+ double positive target cells. Engraftment occurred in all patients (sustained primary, n = 8; after reconditioning, n = 2). No primary acute graft versus host disease (GvHD) >/= grade II or chronic GvHD was observed. The patients showed a rapid platelet recovery (median time to independence from substitution = 13.5 d), whereas T cell regeneration was variable. Five patients are alive with a median follow-up of 10 months. Our data demonstrates the feasibility of CD133+ selection for transplantation from alternative donors and encourages further trials with total CD133+ separated grafts.

Upper respiratory tract infection in athletes: influence of lifestyle, type of sport, training effort, and immunostimulant intake

Epidemiological evidence suggests that heavy acute or chronic exercise is related to an increased incidence of upper respiratory tract infections in athletes, while moderate exercise is believed to be protective. During the past years, many groups have investigated the association between changes within the immune system and exercise at different intensity levels. Although following strenuous exercise, some immunologic alterations were quite consistent and reproducible, e.g. neutrophilia, lymphopenia, and depression of natural killer cell activity, some findings were divergent or strongly dependent on the study design and athletes investigated. Lately, interesting results in the field of psychoneuroimmunolgy as well as new insights in the relationship between macro- and micronutrient and the immune system have brought up new fields of research interest. There is growing evidence that e.g. lifestyle factors, the coping with daily stress, and dietary behavior are important cofactors in the immune response to exercise. The present work gives a short review on the literature dealing with URTI in athletes with special reference to the above mentioned cofactors. In addition, the results of a recent investigation concerning training and associated lifestyle patterns in German athletes are presented.

HSP expression in human leukocytes is modulated by endurance exercise

PURPOSE

Temperature increase, oxidative stress, and inflammatory reactions after endurance exercise were expected to stimulate the synthesis of heat shock proteins (HSP) in peripheral blood leukocytes. Furthermore, it was of interest whether regular endurance training influences HSP expression.

METHODS

The expression of HSP27, HSP60, HSP70, constitutive HSC70, and HSP90 in the cytoplasma and surface of lymphocytes, monocytes, and granulocytes of 12 trained athletes was analyzed by flow cytometry before and after (0, 3, and 24 h) a half marathon. Twelve untrained persons at rest were included as control.

RESULTS

After the race, there was a significantly greater percentage of leukocytes expressing cytoplasmic HSP27, HSP60, and HSP70 (P < 0.01), whereas HSC70 and HSP90 remained unchanged. The fluorescence intensity increased significantly in monocytes for HSP27 (0 and 3 h) and HSP70 (0, 3, and 24 h) and in granulocytes, only 24 h postexercise for HSP70. The percent values of trained athletes at rest were significantly lower compared with untrained persons (P < 0,01).

CONCLUSIONS

Strenuous exercise increased HSP expression in blood immediately after the run, indicating a protective function of HSP in leukocytes of athletes to maintain function after heavy exercise. The downregulation of HSP-positive cells in trained athletes at rest seems to be a result of adaptation mechanisms to regular endurance training.

Zinc, iron, and magnesium status in athletes--influence on the regulation of exercise-induced stress and immune function

Intense physical exercise has been shown to be associated with immunosuppression and increased rate of infection. The immunosuppressive effect of exhaustive exercise has been attributed to a reduced helper/suppressor T-cell ratio, low salivary levels of immunoglobulin-A, decreased lymphocyte proliferative response and natural killer cell activity, and elevation of stress hormones. Yet some athletes can withstand intense training periods without health problems while others are prone to infections. Thus it has been postulated that other factors may interfere with immunoregulation. The notion that macro- and micronutrients are involved in the regulation of immunological processes and the ability to cope with muscular and systemic exercise stress has been gaining attention. Particularly trace elements have been shown to be related to cell mediated and humoral immunity such as NK-cell activity, T- and B-cell functions, and cytokine release. Many investigations have reported decreased concentrations of trace elements in blood and tissues after training and competition. However, the magnitude of losses is highly dependent on the type and intensity of exercise, the individual regulatory state, and most important, nutrition. This paper reviews the data on zinc, iron, and magnesium status in athletes and summarizes the consequences of deficiencies in these trace elements regarding exercise tolerance and immune function. These elements were chosen since there is evidence they are related to exercise-induced stress and immune function.

Similarities and differences of the immune response to exercise and trauma: the IFN-gamma concept

Similar to physical fitness, fitness of the immune system requires training. Animals that have been raised under sterile conditions have a poor immune system and fail to thrive. "Immune training" is normally provided by contact with live microorganisms or immunizations. Increasing evidence has suggested that moderate sports can decrease the frequency of infections while excessive, exhausting exercise can lead to the opposite, a situation that has been described by a J-curve. Following prolonged exhausting exercise, a transient partial suppression of several immune functions can be shown, and it has been suggested that this period provides a window for invasion of microbes. On the basis of data showing that endotoxin-inducible interferon-gamma (IFN-gamma) production is virtually abrogated for a short period following excessive exercise, we present the hypothesis that the rigorous regulatory blockade of one of the ways of IFN-gamma induction may be critically involved in causing the transient immunosuppression following exhaustive exercise stress.

Similarities and differences of the immune response to exercise and trauma: the IFN-γ concept

Similar to physical fitness, fitness of the immune system requires training. Animals that have been raised under sterile conditions have a poor immune system and fail to thrive. "Immune training" is normally provided by contact with live microorganisms or immunizations. Increasing evidence has suggested that moderate sports can decrease the frequency of infections while excessive, exhausting exercise can lead to the opposite, a situation that has been described by a J-curve. Following prolonged exhausting exercise, a transient partial suppression of several immune functions can be shown, and it has been suggested that this period provides a window for invasion of microbes. On the basis of data showing that endotoxin-inducible interferon-gamma (IFN-gamma) production is virtually abrogated for a short period following excessive exercise, we present the hypothesis that the rigorous regulatory blockade of one of the ways of IFN-gamma induction may be critically involved in causing the transient immunosuppression following exhaustive exercise stress.Key words: exhaustive exercise, immune functions, immunosuppression, interferon-gamma, cytokines.

Impaired production of cytokines in a case of human leishmaniasis

A patient presented with the unique clinical picture of diffuse cutaneous and mucosal leishmaniasis caused by Leishmania tropica. Elevated serum levels of several cytokines including interleukin (IL) 2, interferon gamma (IFN-gamma), and tumor necrosis factor alpha were found. All cytokine levels returned to normal during therapy. No IL-10 or IL-4 levels were detectable. In whole blood cultures, induction of IFN-gamma by lipopolysaccharide (LPS) was completely negative, even after therapy. Concanavalin A (Con A)-induced release of IFN-gamma, like Con A-induced release of the other cytokines, was only initially impaired but returned to normal during therapy. Induction of the other cytokines by LPS was never impaired. The low expression of human leukocyte antigen DR on monocytes increased during IFN-gamma therapy but dropped when IFN-gamma treatment was ceased. We conclude that in this patient one or more of the routes of IFN-gamma production was impaired, thus resulting in insufficient IFN-gamma production in the infected lesions (although IFN-gamma was systemically present).

Fas- or ceramide-induced apoptosis is mediated by a Rac1-regulated activation of Jun N-terminal kinase/p38 kinases and GADD153

In the present study, we show that Fas receptor ligation or cellular treatment with synthetic C6-ceramide results in activation or phosphorylation, respectively, of the small G-protein Rac1, Jun N-terminal kinase (JNK)/p38 kinases (p38-K), and the transcription factor GADD153. A signaling cascade from the Fas receptor via ceramide, Ras, Rac1, and JNK/p38-K to GADD153 is demonstrated employing transfection of transdominant inhibitory N17Ras, N17Rac1, c-Jun, or treatment with a specific p38-K inhibitor. The critical function of this signaling cascade is indicated by prevention of Fas- or C6-ceramide-induced apoptosis after inhibition of Ras, Rac1, or JNK/p38-K.