Total Synthesis of a Partial Structure from Arabinogalactan and Its Application for Allergy Prevention.

Arabinogalactan, a microheterogeneous polysaccharide occurring in plants, is known for its allergy-protective activity, which could potentially be used for preventive allergy treatment. New treatment options are highly desirable, especially in a preventive manner, due to the constant rise of atopic diseases worldwide. The structural origin of the allergy-protective activity of arabinogalactan is, however, still unclear and isolation of the polysaccharide is not feasible for pharmaceutical applications due to a variation of the activity of the natural product and contaminations with endotoxins. Therefore, a pentasaccharide partial structure was selected for total synthesis and subsequently coupled to a carrier protein to form a neoglycoconjugate. The allergy-protective activity of arabinogalactan could be reproduced with the partial structure in subsequent in vivo experiments. This is the first example of a successful simplification of arabinogalactan with a single partial structure while retaining its allergy-preventive potential.

Multivalency Beats Complexity: A Study on the Cell Uptake of Carbohydrate Functionalized Nanocarriers to Dendritic Cells.

Herein, we report the synthesis of carbohydrate and glycodendron structures for dendritic cell targeting, which were subsequently bound to hydroxyethyl starch (HES) nanocapsules prepared by the inverse miniemulsion technique. The uptake of the carbohydrate-functionalized HES nanocapsules into immature human dendritic cells (hDCs) revealed a strong dependence on the used carbohydrate. A multivalent mannose-terminated dendron was found to be far superior in uptake compared to the structurally more complex oligosaccharides used.

A Photoinduced Cobalt-Catalyzed Synthesis of Pyrroles through in Situ-Generated Acylazirines.

Tetrasubstituted pyrroles can be synthesized in a one-pot procedure from isoxazoles. The process includes the photoinduced in situ formation of acylazirines combined with a subsequent cobalt(II)-catalyzed ring expansion with 1,3-diketones.

Thrombocytopenia in common variable immunodeficiency patients - clinical course, management, and effect of immunoglobulins.

Common variable immunodeficiency (CVID) is a primary immunodeficiency of humoral immunity with heterogeneous clinical features. Diagnosis of CVID is based on hypogammaglobulinaemia, low production of specific antibodies, and disorders of cellular immunity. The standard therapy includes replacement of specific antibodies with human immunoglobulin, prophylaxis, and symptomatic therapy of infections. High prevalence of autoimmunity is characteristic for CVID, most commonly: thrombocytopaenia and neutropaenia, celiac disease, and systemic autoimmune diseases. The study included seven children diagnosed with CVID and treated with immunoglobulin substitution from 2 to 12 years. Thrombocytopenia was diagnosed prior to CVID in four children, developed during immunoglobulin substitution in three children. In one boy with CVID and thrombocytopaenia, haemolytic anaemia occurred, so a diagnosis of Evans syndrome was established. Therapy of thrombocytopaenia previous to CVID included steroids and/or immunoglobulins in high dose, and azathioprine. In children with CVID on regular immunoglobulin substitution, episodes of acute thrombocytopaenia were associated with infections and were treated with high doses of immunoglobulins and steroids. In two patients only chronic thrombocytopaenia was noted. Splenectomy was necessary in one patient because of severe course of thrombocytopaenia. The results of the study indicated a supportive role of regular immunoglobulin substitution in patients with CVID and chronic thrombocytopaenia. However, regular substitution of immunoglobulins in CVID patients did not prevent the occurrence of autoimmune thrombocytopaenia episodes or exacerbations of chronic form. In episodes of acute thrombocytopaenia or exacerbations of chronic thrombocytopaenia, infusions of immunoglobulins in high dose are effective, despite previous regular substitution in the replacing dose.

[Immune tolerance mechanisms--brief review]. / Krótka charakterystyka mechanizmów tolerancji immunologicznej.

The purpose of the immune system is not only to fight off pathogens but also to keep a tolerance to self-antigens. In central tolerance, major mechanisms include apoptosis (for T cells) and receptor editing (for B cells). Regulatory T cells appear to be the most important in peripheral tolerance. Innate immune cells also influence the maintenance of immune tolerance. We have provided an overall review of all these mechanisms. Successful restoration of the immune tolerance is the target of new strategies in autoimmune diseases therapy.

An attempt to estimate the minimal number of Poles infected and treated for malaria in Poland and abroad.

BACKGROUND: Malaria is one of the three most dangerous infectious diseases in the world. According to official statistics, there are a few dozen cases in Poland annually while the number of Poles treated abroad or self-treating remains unknown. Poland has been declared to be malaria-free since 1963 and nowadays all cases are imported. The aim of the study is to determine the minimal number of malaria cases in Poles at home and abroad in the last decade. MATERIALS AND METHODS: The medical records of 4,710 patients tested for malaria in the Department of Tropical Parasitology in the years 2003-2012 were analysed. Two spreadsheets were created, which only included people with a history of malaria diagnosed in the reference centre where indirect immunofluorescent-antibody assay (IFA) for Plasmodium falciparum antigen proved positive. The minimum number of Poles who have had malaria at home and abroad was calculated on the basis of positive IFA results; the rate of all treated malaria patients in Poland in relation to those treated in the reference centre and the actual number of Poles with malaria diagnosed at home was calculated. RESULTS: A group of 376 people with positive serologic tests results in indirect immunofluorescent antibody assay with titre ≥ 1:20 were received, including 227 patients with positive serologic results with titre ≥ 1:80. The rate of the overall number of malaria cases in Poland compared to the number of malaria cases in the University Centre for Maritime and Tropical Medicine Hospital was determined as 3.47:1. It was demonstrated that every year at least 174 to 211 Poles staying abroad may suffer from malaria. CONCLUSIONS: This is the first attempt to estimate the minimal number of Poles infected and treated for malaria in Poland and abroad. The estimated number is 8-10 times greater than the number of registered cases in Poland.

Chemoenzymatic synthesis of functional sialyl Lewis(x) mimetics with a heteroaromatic core.

Functional mimetics of the sialyl Lewis(X) tetrasaccharide were prepared by the enzymatic sialylation of a 1,3-diglycosylated indole and a glycosyl azide, which was subsequently transformed into a 1,4-diglycosylated 1,2,3-triazole, by using the trans-sialidase of Trypanosoma cruzi. These compounds inhibited the binding of E-, L-, and P-selectin-coated nanoparticles to polyacrylamide-bound sialyl-Lewis(X) -containing neighboring sulfated tyrosine residues (sTyr/sLe(X) -PAA) at low or sub-millimolar concentrations. Except for E-selectin, the mimetics showed higher activities than the natural tetrasaccharide.

Haploinsufficiency at the human IFNGR2 locus contributes to mycobacterial disease.

Mendelian susceptibility to mycobacterial diseases (MSMD) is a rare syndrome, the known genetic etiologies of which impair the production of, or the response to interferon-gamma (IFN-γ). We report here a patient (P1) with MSMD whose cells display mildly impaired responses to IFN-γ, at levels, however, similar to those from MSMD patients with autosomal recessive (AR) partial IFN-γR2 or STAT1 deficiency. Whole-exome sequencing (WES) and Sanger sequencing revealed only one candidate variation for both MSMD-causing and IFN-γ-related genes. P1 carried a heterozygous frame-shift IFNGR2 mutation inherited from her father. We show that the mutant allele is intrinsically loss-of-function and not dominant-negative, suggesting haploinsufficiency at the IFNGR2 locus. We also show that Epstein-Barr virus transformed B lymphocyte cells from 10 heterozygous relatives of patients with AR complete IFN-γR2 deficiency respond poorly to IFN-γ, in some cases as poorly as the cells of P1. Naive CD4(+) T cells and memory IL-4-producing T cells from these individuals also responded poorly to IFN-γ, whereas monocytes and monocyte-derived macrophages (MDMs) did not. This is consistent with the lower levels of expression of IFN-γR2 in lymphoid than in myeloid cells. Overall, MSMD in this patient is probably due to autosomal dominant (AD) IFN-γR2 deficiency, resulting from haploinsufficiency, at least in lymphoid cells. The clinical penetrance of AD IFN-γR2 deficiency is incomplete, possibly due, at least partly, to the variability of cellular responses to IFN-γ in these individuals.

T lymphocytes and NK cells in X-linked agammaglobulinemia.

Seven boys with diagnosis of X-linked agammaglobulinemia on regular substitution of immunoglobulins were included into study. The patients showed episodes of infections but the clinical course was mild with good response to antibiotics. All patients developed, with time, the chronic sinusitis with proliferation of mucous membrane, two patients showed bronchiectases. The number of T lymphocytes, ratio of CD4:CD8 subpopulations, response to stimulation and NK number were assayed with flow cytometry and cell culture. Results showed CD4:CD8 ratio within normal value in majority of patients, reverse ratio in 2 boys, increased number of activated T cells (CD3/HLA-DR) in one of them. The number of NK cells was different from lack of these cells to high number. Response of T cells to stimulation (mitogens and CD3) were normal in majority of assays. There were no associations between clinical course and observed changes in T or NK cell populations. Further studies on number and function of NK cells are needed.

[Primary selective IgM deficiency--forgotten primary immunodeficiency?]. / Izolowany niedobór IgM--ignorowany pierwotny niedobór odpornosci?

Immunoglobulin M is a pentamer found in the intravascular compartment and on the surface of B lymphocytes. It is the antibody isotype produced initially in the immune response, and the first immunoglobulin class to be synthesized by a fetus or newborn. IgM antibodies do not cross the placenta. Decreased levels of IgM have been associated with autoimmune disease, several primary immunodeficiency but exist also as selected primary immunodeficiency.

Synthetic antitumor vaccines containing MUC1 glycopeptides with two immunodominant domains-induction of a strong immune response against breast tumor tissues.

A shot in the arm for cancer treatment: two MUC1 tetanus toxoid vaccines were synthesized and induced a strong immune response in mice. The antibodies elicited by the vaccines show a high selectivity for the tumor cells in mammary carcinoma tissues and also distinguish between tumor tissues at different stages.

[Mechanisms of immunoglobulins activity]. / Mechanizmy dzialania immunoglobulin.

Intravenous immunoglobulin (IVIG) products are derived from plasma pools of thousands of healthy donors. These immunoglobulin concentrates contain large number of antibodies as well trace levels various other immunologically active molecules. Therapeutic Ig formulations contain intact IgG molecules, with variable amounts of monomeric and dimeric form existing in a dynamic equilibrium. Paradoxically, IgG can exert both pro-and anti-inflammatory activities, depending on its concentration. IVIG have been used for the treatment of primary immunodeficiency disorders for more than 25 years. IVIG products are also effective in the treatment of autoimmune and inflammatory disorders; however, the precise mechanism (s) of action is not known. Clinical and laboratory studies have documented various mechanisms of action of IVIG. The complex network of immunological reactions resulting from the infusion of IVIG includes changes in several cytokines, interactions with dendritic cells, T-and B-cell effects, macrophage effects, mediated by distinct Fc-gamma receptors. IVIG is also a recently recognized modifier of complement activation and injury. The complement--scavenging ability of Ig implies expansion of the use of IVIG to all disease in which generation of complement fragments plays a crucial role in pathogenesis. Recent studies showed that the anti-inflammatory activity of IVIG result from a minor population of the pooled IgG molecules that contains terminal a-2,6 sialic acid linkages on their Fc-linked glycans. This fully processed glycan is found in 1-3% of IgG in IVIG, which may explain the requirement for a high dose of IVIG. Recent data demonstrate, that the anti-inflammatory properties of IVIG can be recapitulated with fully recombinant preparation of appropriately sialylated IgG Fc fragments. This recombinant preparation had a 35 fold enhanced activity and potentially could be used at much lower doses than IVIG preparation in the treatment of autoimmune disorders.

Preparations of intravenous immunoglobulins diminish the number and proinflammatory response of CD14+CD16++ monocytes in common variable immunodeficiency (CVID) patients.

We have studied the effect of intravenous immunoglobulins (IVIG) on monocyte subpopulations and cytokine production in patients with CVID. The absolute number of CD14(+)CD16(++) monocytes decreased on average 2.5-fold 4h after IVIG and after 20h returned to the baseline. The cytokine level in the supernatants of peripheral blood mononuclear cells (PBMC) after ex vivo LPS stimulation demonstrated the >2-fold decrease in TNF production 4h after IVIG. The TNF expression, which is higher in the CD14(+)CD16(++) monocytes, was decreased in these cells by IVIG in 4/7 CVID cases. In vitro exposure of the healthy individuals' monocytes to the IVIG preparation resulted in reduced TNF production, which was overcome by blockade of the FcγRIIB in the CD14(+)CD16(++) CD32B(high) monocytes. Our data suggest that reduction in the number of CD14(+)CD16(++) monocytes and the blockade of their cytokine production via triggering CD32B can contribute to the anti-inflammatory action of IVIG.

Dengue antibodies in Polish travellers returning from the tropics. Evaluation of serological tests.

Dengue is a viral disease caused by an RNA virus of the genus Flavivirus, family Flaviviridae, occurring as four serotypes (DEN-1, -2, -3, -4). It is transmitted to humans by the Aedes mosquitoes, mainly A. aegypti. The occurrence of dengue is strictly related with their preferred breeding areas. Dengue endemic regions are inhabited by some 2.5 billion people. 50-100 million cases of dengue fever and up to 1 million cases of dengue haemorrhagic fever are noted worldwide in more than 100 countries every year. The aim of the reported examinations was to diagnose dengue virus infections in returning travellers. In the years 2006-2009 serological tests were performed in 753 persons. In the diagnostics we used ELISA to find IgM and/or IgG class of antibodies against dengue virus, rapid immunochromatographic (cassette) test, NS1 viral antigen detection by ELISA, and virus RNA detection by RT-PCR method. IgM or IgG class antibodies, and both classes simultaneously, were detected in 19.8% of the examined cases. The greatest number of infections came from India and the Far East, next from South and Central America, and the smallest number from Africa. Sixteen patients with diagnosed dengue, including three cases of dengue haemorrhagic fever, were hospitalized.

The B-cell compartment in the peripheral blood of children with different types of primary humoral immunodeficiency.

The aim of this study was to evaluate the B-cell compartment in the peripheral blood of children with different types of hypogammaglobulinemia: common variable immunodeficiency (CVID), transient hypogammaglobulinemia of infancy (THI), and selective IgA deficiency (SIgAD). We analyzed by flow cytometry the changes in the B-cell subsets with age and showed that children with an early-onset CVID develop similar pattern of B-cell subsets as adult patients with CVID with age, as the levels of memory B cells (CD19/CD27) and class-switched memory B cells (CD19/CD27/IgD/IgM), in contrast to age-matched control group, did not increase with age. Children with SIgAD displayed similar changes as patients with CVID only within the class-switched memory B-cell subpopulation. No significant differences in the level of memory B cells and class-switched memory B cells in children with THI in comparison to age-matched control group were observed. There were no differences in the percentage of immature B cells (CD19/CD21) among all studied groups. As B-cell subsets in children with THI were normal during entire period of hypogammaglobulinemia, the persistence of low levels of memory B-cell subsets in some children may facilitate the diagnosis of CVID.

Sulfated and non-sulfated glycopeptide recognition domains of P-selectin glycoprotein ligand 1 and their binding to P- and E-selectin.

Total synthesis through block glycosylation and selective chemical O-sulfation of tyrosine residues yielded the glycopeptide recognition domain A (X=SO(3) (-)) of the P-selectin glycoprotein ligand 1, in which the terminal sialic acid of the complex hexasaccharide side chain was replaced by (S)-cyclohexyl lactic acid. In binding assays the O-sulfated structure A showed high affinity towards P-selectin, the non-sulfated towards E-selectin.

Rapid full engraftment and successful immune reconstitution after allogeneic hematopoietic stem cell transplantation with reduced intensity conditioning in Omenn syndrome.

OS is a variant of SCID characterized by generalized erythroderma, alopecia, eosinophilia, and elevated IgE levels. It is fatal unless treated with allogeneic HSCT, which is the only curative approach. However, treatment related complications and graft rejection are major obstacles to the success of treatment. In this report, we describe a patient with OS, complicated by prolonged cytomegalovirus infection, successfully treated by reduced intensity conditioning allogeneic HSCT from sibling donor.