Isotype Concentrations Research Articles

Measuring intraocular antibodies in eyes treated with anti-vascular endothelial growth factor

ObjectiveTo characterize the total intraocular aqueous humour antibody profiles in cases receiving anti-vascular endothelial growth factor (anti-VEGF) for retinal vascular disease compared with controls without retinal pathology. DesignCross-sectional. Participants93 aqueous humour samples: 22 eyes undergoing cataract surgery (controls) and 71 eyes receiving intravitreal injections (IVI) (cases) for macular edema or neovascularization. MethodsAntibody isotyping of aqueous humour was performed using Milliplex MAP Human Isotyping Multiplex Assay. Cases and controls were compared for several outcome measures. ResultsThe primary outcome measure was total mean antibody isotype concentration quantified in the aqueous humour. Secondary outcomes included comparing aqueous humour concentrations with visual acuity, number of IVI received, type of anti-VEGF agent injected, and persistence intra-/subretinal fluid post injection. Mean immunoglobulin M (IgM) concentrations in cases were 19-fold higher compared with controls. Aqueous immunoglobulin G (IgG)1,2,3,4 and immunoglobulin A (IgA) were 2–4-fold higher in cases compared with controls. Disease-specific trends were observed, with diabetic retinopathy (DR) eyes containing the highest amounts of aqueous antibodies. Total number of injections correlated with higher titres of IgG1 (p < 0.001), IgG2 (p < 0.009), and IgG3 (p < 0.001) in all cases analyzed with the strongest correlations seen in DR eyes (r = 0.77, p < 0.001). Presence of aqueous humour antibodies correlated with worse post-IVI best-corrected visual acuity; IgG1 (p < 0.01), IgG2 (p < 0.005), IgG3 (p < 0.01), and IgA (p < 0.003) in all cases analyzed, with the strongest correlations seen in DR eyes (r = 0.74, p < 0.001). ConclusionsIntraocular antibodies are present in the aqueous humour at significantly higher concentrations in eyes receiving IVIs for retinal vascular diseases compared with controls.

Response to pneumococcal vaccination in multiple myeloma.

Background Streptococcus pneumoniae infection causes morbidity and mortality in multiple myeloma patients. Pneumococcal vaccination is commonly given to immunocompromised myeloma patients; however response data are sparse. Here, we present longitudinal response data to pneumococcal vaccination in multiple myeloma patients.MethodTwenty‐eight multiple myeloma patients were included, 25 of whom were newly diagnosed. All the patients received two vaccines Prevnar13® and Pneumo23®. Serotype‐specific IgG was measured by ELISA for all 23 vaccine serotypes at baseline, and then sequentially at different time points postvaccination until treatment ended. Response to vaccination is available for 20 patients. The primary endpoint was the incidence rate of patients who obtained an isotype response serum concentration after vaccination. Secondary endpoints included detailed isotype increase, time to first increase, further assessment of a decreased anti‐pneumococcal serum concentrations following treatment including autologous stem cell transplantation (ASCT), rate of infection with a special attention to pneumococcal infection.ResultsThe median age was 66 years and the male to female ratio was 0.6. Anti‐pneumococcal capsular polysaccharide (anti‐PCP23) IgG, IgG2, IgA, and IgM responses were detected within 1 week postvaccination. Response to at least one subtype of antibody was obtained in 85% (n = 17) of patients, for at least two subtypes in 65% (n = 13), for at least three subtypes in 55% (n = 11), and 2 patients responded to all four subtypes. The median increase in the concentration of anti‐PCP23 isotypes was threefold following vaccination, with the highest increase observed when Pneumo23® was given more than 30 days after Prevnar13®. The anti‐pneumococcal geometric mean concentration decreased significantly for all subtypes over time independently of treatment approaches.ConclusionMyeloma has the ability to demonstrate a response to pneumococcal vaccine, independently of preexisting hypogammaglobulinemia and possibly of treatment‐induced immunodepression. We also observed a drop in the serum response overtime and following autologous transplantation. Further studies in larger sample are needed to understand the benefit of vaccination strategies in these patients.

'25-Hydroxyvitamin D, Autoantigenic and Total Antibody Concentrations: Results from a Danish Case-control Study of Newly Diagnosed Patients with Childhood Type 1 Diabetes and their Healthy Siblings'.

B cells have recently entered the stage as an important accessory player in type 1 diabetes (T1D) etiopathogenesis. Experimental studies suggest regulatory functions of vitamin D on B cells. However, only a few human studies, with considerable methodological limitations, have been conducted within this field. Our objective was to investigate whether higher 25-hydroxyvitamin D (25(OH)D) concentrations were inversely associated with β-cell autoantigens glutamic acid decarboxylase (isoform 65) (GADA) and insulinoma-associated antigen-2A (IA-2A). Further, we also wanted to examine the relationship between 25(OH)D and total antibody concentrations. We randomly selected 500 patients with newly diagnosed T1D and 500 siblings for 25(OH)D, antibody and genetic analysis from the population-based Danish Registry of Childhood and Adolescent Diabetes. The relative change (RC) in the mean concentration of GADA, IA-2A and antibody isotypes by a 10nmol/l increase in 25(OH)D concentration was modelled by a robust log-normal regression model. We found no association between 25(OH)D and GADA [adjusted RC per 10nmol/l increase: 1.00; 95% confidence interval (CI): 0.98-1.02] and IA-2A [adjusted RC per 10nmol/l increase: 0.92; CI: 0.76-1.12]. Further, 25(OH)D was not associated with the total concentration of antibody isotypes [immunoglobulin (Ig)A, IgE, IgG and IgM]. All null findings were unaltered after adjustment for genetic variation in the vitamin D pathway. Physiological concentrations of 25(OH)D are unlikely to have a clinically important effect on antibody concentrations in a paediatric population of newly diagnosed patients with T1D and their healthy siblings.

Immunobiochemical modulations caused by clomazone in Swiss albino mice

BackgroundRecently, we reported immunological and hematological perturbations in Swiss albino mice exposed to clomazone (CMZ) (Nassef, The Egyptian Journal of Experimental Biology (Zoology) 13(1):91–101, 2017).AimTo continue searching immunological perturbations of CMZ, the main goal of the current study was to investigate the probable immunobiochemical perturbations caused by CMZ and to evaluate the alleviating role of vitamin C.MethodsTo asses this goal, mice were intraperitoneally (i.p.) injected with vitamin C (1136 μM/kg), CMZ (46 μM/kg), or CMZ plus vitamin C with the same dose of each, daily for 4 weeks. Changes in relative weights of immune-related organs (spleen and thymus), renal functions (urea and creatinine), liver functions [alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and total protein], and immunoglobulin (Ig) isotype (IgA, IgG, and IgM) concentrations in addition to the proliferative capacity of CMZ-exposed murine lymphocytes were investigated.ResultsResults showed that CMZ injection caused a significant decrease in body weight gain along with significant decrease in the relative weights of the spleen and thymus. Values of ALT, AST, and ALP were significantly elevated, while total protein and LDH were significantly decreased in CMZ-exposed mice. CMZ injection led to significant increases in the levels of serum urea and creatinine. Moreover, the levels of serum IgA, IgG, and IgM in CMZ-treated mice were significantly lower than those in PBS-treated mice. Reduced lymphocyte proliferation capacity was observed in CMZ-treated mice. Interestingly, pre-treatment of vitamin C to CMZ-exposed mice mildly alleviated CMZ-induced immunobiochemical perturbations. Therefore, vitamin C mildly alleviated CMZ-induced immunobiochemical impacts, but it was not completely protective.ConclusionFurther studies are needed to assess the relationships between antioxidants and CMZ-induced immunobiochemical perturbations.

Tubulin isotype substitution revealed that isotype combination modulates microtubule dynamics in C. elegans embryos

Microtubules (MTs) are polymers composed of α- and β-tubulin heterodimers that are generally encoded by genes at multiple loci. Despite implications of distinct properties depending on the isotype, how these heterodimers contribute to the diverse MT dynamics in vivo remains unclear. Here, by using genome editing and depletion of tubulin isotypes following RNAi, we demonstrate that four tubulin isotypes (hereafter referred to as α1, α2, β1 and β2) cooperatively confer distinct MT properties in Caenorhabditis elegans early embryos. GFP insertion into each isotype locus reveals their distinct expression levels and MT incorporation rates. Substitution of isotype coding regions demonstrates that, under the same isotype concentration, MTs composed of β1 have higher switching frequency between growth and shrinkage compared with MTs composed of β2. Lower concentration of β-tubulins results in slower growth rates, and the two α-tubulins distinctively affect growth rates of MTs composed of β1. Alteration of ratio and concentration of isotypes distinctively modulates both growth rate and switching frequency, and affects the amplitude of mitotic spindle oscillation. Collectively, our findings demonstrate that MT dynamics are modulated by the combination (ratio and concentration) of tubulin isotypes with distinct properties, which contributes to create diverse MT behaviors in vivo.

Applied Protein and Molecular Techniques for Characterization of B Cell Neoplasms in Horses.

Mature B cell neoplasms cover a spectrum of diseases involving lymphoid tissues (lymphoma) or blood (leukemia), with an overlap between these two presentations. Previous studies describing equine lymphoid neoplasias have not included analyses of clonality using molecular techniques. The objective of this study was to use molecular techniques to advance the classification of B cell lymphoproliferative diseases in five adult equine patients with a rare condition of monoclonal gammopathy, B cell leukemia, and concurrent lymphadenopathy (lymphoma/leukemia). The B cell neoplasms were phenotypically characterized by gene and cell surface molecule expression, secreted immunoglobulin (Ig) isotype concentrations, Ig heavy-chain variable (IGHV) region domain sequencing, and spectratyping. All five patients had hyperglobulinemia due to IgG1 or IgG4/7 monoclonal gammopathy. Peripheral blood leukocyte immunophenotyping revealed high proportions of IgG1- or IgG4/7-positive cells and relative T cell lymphopenia. Most leukemic cells lacked the surface B cell markers CD19 and CD21. IGHG1 or IGHG4/7 gene expression was consistent with surface protein expression, and secreted isotype and Ig spectratyping revealed one dominant monoclonal peak. The mRNA expression of the B cell-associated developmental genes EBF1, PAX5, and CD19 was high compared to that of the plasma cell-associated marker CD38. Sequence analysis of the IGHV domain of leukemic cells revealed mutated Igs. In conclusion, the protein and molecular techniques used in this study identified neoplastic cells compatible with a developmental transition between B cell and plasma cell stages, and they can be used for the classification of equine B cell lymphoproliferative disease.

Malondialdehyde-acetaldehyde adducts and anti-malondialdehyde-acetaldehyde antibodies in rheumatoid arthritis.

Malondialdehyde-acetaldehyde (MAA) adducts are a product of oxidative stress associated with tolerance loss in several disease states. This study was undertaken to investigate the presence of MAA adducts and circulating anti-MAA antibodies in patients with rheumatoid arthritis (RA). Synovial tissue from patients with RA and patients with osteoarthritis (OA) were examined for the presence of MAA-modified and citrullinated proteins. Anti-MAA antibody isotypes were measured in RA patients (n = 1,720) and healthy controls (n = 80) by enzyme-linked immunosorbent assay. Antigen-specific anti-citrullinated protein antibodies (ACPAs) were measured in RA patients using a multiplex antigen array. Anti-MAA isotype concentrations were compared in a subset of RA patients (n = 80) and matched healthy controls (n = 80). Associations of anti-MAA antibody isotypes with disease characteristics, including ACPA positivity, were examined in all RA patients. Expression of MAA adducts was increased in RA synovial tissue compared to OA synovial tissue, and colocalization with citrullinated proteins was found. Increased levels of anti-MAA antibody isotypes were observed in RA patients compared to controls (P < 0.001). Among RA patients, anti-MAA antibody isotypes were associated with seropositivity for ACPAs and rheumatoid factor (P < 0.001) in addition to select measures of disease activity. Higher anti-MAA antibody concentrations were associated with a greater number of positive antigen-specific ACPA analytes (expressed at high titer) (P < 0.001) and a higher ACPA score (P < 0.001), independent of other covariates. MAA adduct formation is increased in RA and appears to result in robust antibody responses that are strongly associated with ACPAs. These results support speculation that MAA formation may be a cofactor that drives tolerance loss, resulting in the autoimmune responses characteristic of RA.

7th International Immunoglobulin Conference: Immunoglobulin in clinical practice.

Immunoglobulin (Ig) replacement therapy has been the mainstay of primary immunodeficiencies (PID) treatment for more than 30 years and has substantially changed the lives of patients. This review focuses on aspects of Ig use in clinical practice in addition to discussing prioritizing future Ig use. Despite Ig therapy, PID patients continue to be predisposed to recurrent, subclinical respiratory tract infections, which may lead to chronic lung disease. Research has shown that one of the underlying reasons for this deterioration in lung function is the differential distribution and concentration of Ig isotypes in the airway lumen. Further to this, the relationship between Ig dose and infection outcome is explored, expanding on end-of-cycle loss of efficacy (wear-off) particularly with intravenous immunoglobulin (IVIg), how this can confound the determination of optimal IgG dose and how our aim of treatment should be to improve clinical outcome. This review goes on to discuss the safety of Ig replacement therapy, which is generally well tolerated by most patients, compares the rates of systemic adverse reactions between IVIg and SCIg and highlights the advantages of SCIg administration in this respect, including the use of pre-infused subcutaneous recombinant human hyaluronidase to aid subcutaneous infusion volumes. The growing demand for Ig replacement therapy is challenging physicians; here we show the development of prioritization algorithms to assist in identifying those who will benefit most from this clinically valuable therapy.

Rapeseed oil and ginseng saponins work synergistically to enhance Th1 and Th2 immune responses induced by the foot-and-mouth disease vaccine.

Previous investigations demonstrated that saponins isolated from the root of Panax ginseng C. A. Meyer (i.e., ginseng root saponin [GS-R]) had adjuvant activity. In the present study, the combined effects of rapeseed oil (RO) and GS-R on the immune responses elicited by foot-and-mouth disease (FMD) vaccine were investigated by measuring FMD virus (FMDV)-specific antibody levels, cytokine levels, lymphocyte proliferation, and long-lived IgG-secreting plasma cells from bone marrow in a mouse model. The results indicated that RO in combination with GS-R significantly enhanced serum IgG and isotype concentrations, gamma interferon (IFN-γ) and interleukin 5 (IL-5) levels, splenocyte proliferative responses to stimulations with concanavalin A (ConA), lipopolysaccharide (LPS), and FMDV antigen, and the numbers of IgG-secreting plasma cells in the bone marrow, suggesting that RO/GS-R enhanced both Th1 and Th2 immune responses. In addition, no significant difference was found between RO/GS-R and the commercial adjuvant oil ISA 206 in the promotion of FMD vaccine-induced immune responses. Considering the vegetable origin of RO and GS-R and the potent adjuvant activity, RO/GS-R should be studied further for the development of veterinary vaccines, especially for use in food animals in order to promote food safety.

Clinically Unsuspected Cryoglobulinemia: Cases That Present as Laboratory Artifact

On the basis of anecdotal instances in which atypical laboratory findings suggested the possibility of unsuspected cryoglobulinemia, we applied predetermined criteria to determine how often such findings predict the presence of clinically significant cryoglobulinemia. The laboratory criteria are smeared M-spike (paraprotein) in agarose gel serum protein electrophoresis, precipitated protein at the serum application point of agarose electrophoresis gel, greater than 50% quantitative discrepancy between the densitometrically estimated M-spike and the relevant corresponding serum immunoglobulin isotype concentration from the same specimen, and smeared protein observed on an agarose electrophoresis immunofixation gel. Cases that fulfilled any of these criteria were prospectively collected for 2 years. Brouet types and clinical findings were determined in cases where cryoglobulins were subsequently identified and clinical data available. Among 83 patients in whom any of the above laboratory findings were identified, 52 had subsequent cryoglobulin evaluations. Fourteen of these 52 patients had cryoglobulinemia. Findings indicative of clinically significant cryoglobulinemia were present in 8 of the 10 patients in whom follow-up clinical data were available.

17-β Estradiol reduces atherosclerosis without exacerbating lupus in ovariectomized systemic lupus erythematosus-susceptible LDLr−/− mice

ObjectiveTo test the hypothesis that estrogen treatment in a radiation chimera mouse model of systemic lupus erythematosus (SLE) and atherosclerosis will increase SLE-associated atherosclerosis by increasing autoantibody production and inflammation. MethodsWe used a radiation chimera mouse model in which bone marrow from the polygenic B6.Sle1.2.3 model of SLE was transferred to the low density lipoprotein receptor knock out (LDLr−/−) model of atherosclerosis on a C57BL/6 background (Sle/LDLr−/−). Ovariectomized chimeric mice were treated for 10 weeks with either 5.6 μg/day of 17β-estradiol or placebo; outcomes included atherosclerosis plaque size, anti-dsDNA autoantibody production and renal pathology. ResultsMean atherosclerosis plaque size was 67.4 ± 7.6% smaller in the estrogen treated group (p < 0.0001). Estrogen treated Sle/LDLr−/− mice had no significant difference in serum cholesterol concentration, lipoprotein distribution, anti-dsDNA autoantibody concentration, antibody isotype concentration and renal histopathology score compared to placebo. However, they had significantly lower mean urine protein to urine creatinine ratio (UP:UC). There was no correlation between atherosclerosis lesion size and either the renal histology score or UP:UC ratio in Sle/LDLr−/− mice. ConclusionThese results indicate that 17β-estradiol is atheroprotective within the context of murine SLE independent of changes in serum cholesterol concentration, autoantibody concentration, or renal pathology. The SLE phenotype in Sle/LDLr−/− mice is not exacerbated by exogenous 17β-estradiol administration, and the reduced UP:UC ratio suggests a protective effect against lupus nephritis.

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Aim Single antigen beads (SAB) assays are routinely used to identify anti-HLA antibodies and the level of detection is commonly communicated as mean fluorescence intensity (MFI). Many factors may contribute to an MFI value, including antibody concentration and interference of non-IgG isotypes. Here we purified polyclonal anti-HLA antibodies from sensitized patients and tested the influence of antibody concentration and non-IgG isotypes on MFI. Methods Using an HLA-DR11 affinity column, we purified anti-HLA-DR11 antibodies from 13 sensitized human sera. The purified anti-HLA antibodies were then tested on a SAB assay using a secondary that only recognizes IgG isotypes. IgG isotypes were separated from IgM and IgA isotypes via size exclusion HPLC. Reduction of multimeric antibodies (IgM, IgA) to monomers was preformed with 100 mM DTT at 4 °C overnight with a total antibody concentration at 1 mg/ml. Results Serial dilution experiments with affinity purified anti-HLA antibodies demonstrated a strong correlation between antibody concentration and MFI within a single patient. However, between patients, the MFI value did not correlate to an antibody concentration – MFI was not comparable between patients. When IgM and IgA multimers were separated from IgG, a significant increase in MFI was observed compared to the original mix of isotypes. Furthermore, reduction of IgM and IgA into monomers with IgG did not impact MFI values as the monomeric mix provided an MFI matching the IgG monomer only. Conclusions Multiple factors influence SAB MFI. Here we tested the influence of both antibody concentration and the presence of IgM, and IgA on MFI. We show that MFI correlates with antibody concentration within a particular patient but not between patients. We also show that mixing IgM and IgA multimers (but not monomers) with IgG antibodies interferes with the assay by reducing MFI. Together these data exemplify the complexity of anti-HLA antibodies and factors that influence the SAB that is used to detect them. Cate: Pure Protein: Employee. McMurtrey: Pure Protein: Consultant. Buchli: Pure Protein: Employee. VanGundy: Pure Protein: Employee. Osborn: Pure Protein: Employee. Mojsilovic: Pure Protein: Employee. Hildebrand: Pure Protein: Science Med Advisor.

Blinded, controlled field trial of two commercially available Mycoplasma bovis bacterin vaccines in veal calves

Mycoplasma bovis is an etiologic agent of pneumonia, arthritis, and otitis in young calves, such as those found in the special-fed veal industry. We conducted a blinded, controlled trial of two commercially available M. bovis bacterin vaccines for the prevention of respiratory disease in calves associated with M. bovis infection. Calves were randomly assigned to a subcutaneous treatment of vaccine A (n=50), adjuvant A (n=50), vaccine B (n=50), or 0.9% sterile saline solution (n=50) beginning at 27 days of age. Upper-respiratory tract colonization was not impacted by vaccination status. Vaccine A significantly reduced the presence of lung lesions (p=0.0325), however there was no significant reduction of M. bovis in lung lesions. Vaccine B did not significantly reduce total lung lesions or M. bovis-specific lung lesions. The relative risk was determined to be 0.56, 1.0, and 1.36 for vaccine A, adjuvant A, and vaccine B, respectively. There was no association between the total specific antibody isotype (IgM, IgG1, IgG2, IgA) concentrations or M. bovis antibodies and the M. bovis-associated morbidity in the veal calves. Under the field conditions of this study, observed vaccine efficacy for vaccine A and vaccine B was 44% and less than 1%, respectively.

Humoral and cellular immune responses in dogs with inapparent natural Leishmania infantum infection

Molecular analysis, serology and immunophenotyping for T lymphocytes and their subsets, B lymphocytes and monocytes were performed on dogs naturally infected with Leishmania infantum. Animals were categorised as asymptomatic dogs I (AD-I), with negative serology and positive molecular results, and asymptomatic dogs II (AD-II), with positive serology and positive molecular results, and these were compared to symptomatic dogs (SD) and control dogs (CD). AD-I exhibited immunophenotypic features similar to those of CD, including isotype profiles and concentrations of monocytes. Similar biomarkers were found in AD-II and SD, such as, higher levels of immunoglobulins IgG, IgG2, IgM and IgA and higher concentrations of eosinophils. High frequencies of T lymphocytes and CD4(+) T cells were observed in both AD-I and AD-II compared to SD, whereas CD8(+) T cells were higher only in AD-II compared with SD. Analysis of B lymphocytes revealed an increased frequency of this cell type only in AD-II animals compared with SD. Asymptomatic dogs appear to have a dichotomous infection spectrum that can influence the humoral and cellular immunological status during canine visceral leishmaniasis.

Multiplex immunoglobulin isotyping assays for human, mouse or rat serum samples (65.25)

Abstract The determination of serum immunoglobulin isotype concentrations is an important indicator of immunological health. We have constructed several multiplex isotyping assays on the Luminex® assay platform. These assays allow for the analysis of human, mouse and rat serum, tissue culture or body fluid samples. The human isotyping assay enables the quantification of immunoglobulins A, M, G1, G2, G3 and G4 in a single assay well. While the mouse isotyping assay cover immunoglobulins A, M, G1, G2A, G2B, and G3, and the rat isotyping immunoglobulins A, E, M, G1, G2A, G2B, G2C. Since the concentrations of IgE in human and mouse samples are typically much lower than the other immunoglobulin isotypes we have also designed separate assays for mouse and human IgE analysis. This collection of assays allows for the rapid, multiplex analysis of major immunoglobulin isotypes in the human , as well as the two predominant research maodels, rat and mouse.

Expression of essential B cell genes and immunoglobulin isotypes suggests active development and gene recombination during equine gestation

Many features of the equine immune system develop during fetal life, yet the naïve or immature immune state of the neonate renders the foal uniquely susceptible to particular pathogens. RT-PCR and immunohistochemical experiments investigated the progressive expression of developmental B cell markers and immunoglobulins in lymphoid tissues from equine fetus, pre-suckle neonate, foal, and adult horses. Serum IgM, IgG isotype, and IgA concentrations were also quantified in pre-suckle foals and adult horses. The expression of essential B cell genes suggests active development and gene recombination during equine gestation, including immunoglobulin isotype switching. The corresponding production of IgM and IgG proteins is detectable in a limited scale at birth. Although the equine neonate humoral response seems competent, B cell activation factors derived from antigen presenting cells and T cells may control critical developmental regulation and immunoglobulin production during the initial months of life.

Circulating CD23+B Cell Subset Correlates with the Development of Resistance toSchistosoma mansoniReinfection in Occupationally Exposed Adults Who Have Undergone Multiple Treatments

Elevated immunoglobulin E (IgE) levels are often associated with resistance to reinfection in human schistosomiasis. However, Although B cells are the source of schistosome-specific IgE, little is known about B cell subsets or their functions in this infection. We evaluated B cells and their expression of the low-affinity IgE receptor (CD23) in a unique cohort of men occupationally exposed to Schistosoma mansoni and longitudinally followed up through multiple treatments with praziquantel, cures, and reinfections. Resistance levels were calculated on the basis of documented water exposure and reinfection data over many years. The CD23(+) B cell subset was evaluated in whole blood by flow cytometry. Serum antibody isotype and soluble CD23 (sCD23) concentrations were measured by enzyme-linked immunosorbent assay. Expression of membrane CD23 (mCD23) on B cells correlated with the development of resistance against S. mansoni. Higher levels of plasma sCD23, the cleaved form of mCD23, also correlated with resistance and other markers of resistance to reinfection, such as eosinophilia. CD23 may be involved in the development of resistance to schistosome infection through its role in IgE regulation. Understanding these complex host-parasite interactions may lead to insights into the development, mechanisms, and regulation of resistance to reinfection with S. mansoni.

Immunologic evaluation of patients with recurrent ear, nose, and throat infections

Purpose In this study, we aimed to study the frequency of possible underlying immunodeficiency responsible for susceptibility to ear, nose, and throat (ENT) infection. Materials and methods One hundred three (72 males and 31 females) consecutive children and adult patients with history of recurrent or chronic ENT infections, referred by otolaryngologists to the Department of Allergy and Clinical Immunology, Children's Medical Center, Tehran University of Medical Sciences (Tehran, Iran), were enrolled to the study from March 2003 to March 2006. For each patient, demographic information and medical histories of any ENT infections were collected by reviewing the patient's records. We measured immunoglobulin isotype concentrations and immunoglobulin (Ig) G subclasses by nephelometry and enzyme-linked immunosorbent assay methods, respectively. Of 103 patients, 75 received unconjugated pneumococcus polyvalent vaccine, and blood samples were taken before and 21 days after vaccination. Specific antibodies against whole pneumococcal antigens were measured using enzyme-linked immunosorbent assay method. Existence of bronchiectasis was confirmed in each patient using high resolution computed tomography scan. Results Among 103 patients, 17 (16.5%) patients were diagnosed to have defects in antibody-mediated immunity including 6 patients with immunoglobulin class deficiency (2 common variable deficiency and 4 IgA deficiency), 3 with IgG subclass deficiency (2 IgG2 and 1 IgG3), and 8 with specific antibody deficiency against polysaccharide antigens. In our series, bronchiectasis was detected in 5 cases associated with primary immunodeficiency. Conclusions Long-standing history of ENT infections could be an alarm for ENT infections associated with primary antibody deficiency.

Anti-β2-glycoprotein I in childhood immune thrombocytopenic purpura

Immune thrombocytopenic purpura (ITP) etiology is not clarified. Phospholipid antigen antibodies (aPls) occur in ITP patient sera. We studied predictive values of elevated anti-beta2-glycoprotein I (anti-beta2-GP1) or anticardiolipin antibody (aCl) concentrations for secondary ITP detection, comparing levels with steroid therapy responsiveness in three groups of children and adolescents. Participants' antinuclear antibodies, aCls (IgM, IgG) and anti-beta2-GPI (IgG) were assessed. Significantly higher aCl (IgM), aCl (IgG) and anti-beta2-GPI (IgG) mean concentrations occurred in chronic ITP cases compared with acute or control cases. Of chronic ITP cases, 77.8% showed elevated IgG aCl serum concentrations, and all presented increased IgG anti-beta2-GPI serum levels. Significant positive correlation between increased levels of IgG anti-beta2-GPI and increased IgG aCl serum concentrations was determined; these increased IgG concentrations significantly correlated with steroid therapy resistance. A total of 76.1% of ITP cases had positive aPls (all chronic ITP cases, five acute ITP cases). Elevated aCl or anti-beta2-GPI serum IgG isotype concentrations occurred in all nine splenectomized ITP children with positive aPls (three showed increased IgM aCl levels). Follow-up of the initially studied ITP children (2000-2004) revealed 16.7% developed clinical and laboratory criteria of systemic lupus erythrematosus (one acute ITP in remission, six chronic ITP); elevated IgG aCl serum concentrations were found at study start in these seven cases, and six had increased anti-beta2-GPI. IgG classes of both aCls and anti-beta2-GPI may be determinant cofactors for the developing risk of antiphospholipid syndrome or autoimmune diseases in ITP. Great attention should be paid to both assays as predictors for steroid therapy response.

Immune Parameters of Dry Cows Fed Mannan Oligosaccharide and Subsequent Transfer of Immunity to Calves

The objective of this study was to evaluate the benefits of supplementation of mannan oligosaccharide (MOS) to cows during the last 3 wk of the dry period on immune function of the cows and subsequent transfer of passive immunity to their calves. Indicators of nonspecific and specific immunity were evaluated. Cows were vaccinated against rotavirus at 4 and 2 wk before expected parturition. Blood samples were obtained from cows before vaccination and at weekly intervals until calving and from calves at birth and 24h for analysis of serum protein concentrations, packed cell volume, white blood cell counts, white blood cell differentials, and serum rotavirus neutralization titers. Colostrum quantity and quality were measured at calving, and immunoglobulin isotype concentrations in colostrum were determined. Specific immunity was enhanced by MOS supplementation as evidenced by greater serum rotavirus neutralization titers at calving in cows supplemented with MOS compared with control cows. Colostral rotavirus neutralization titers were not affected by treatment. Although numerical differences appeared large, there was a high degree of variability in the colostral rotavirus neutralization titers. Calves from cows fed MOS tended to have greater serum rotavirus neutralization titers compared with calves from cows fed the control diet. There was a tendency for greater increases in serum protein concentrations from birth to 24h in calves from cows fed MOS compared with calves from cows fed the control diet. Results indicate that supplementation of MOS to cows during the dry period enhanced their immune response to rotavirus and tended to enhance the subsequent transfer of rotavirus antibodies to calves.