Abnormalities in the T and NK lymphocyte phenotype in patients with Nijmegen breakage syndrome.

Nijmegen breakage syndrome (NBS) is a rare autosomal recessive disorder characterized by spontaneous chromosomal instability with predisposition to immunodeficiency and cancer. In order to assess the cellular basis of the compromised immune response of NBS patients, the distribution of functionally distinct lymphocyte subsets in peripheral blood was evaluated by means of double-colour flow cytometry. The study involved the 36 lymphopenic patients with a total lymphocyte count < or =1500 microl (group A) and seven patients (group B) having the absolute lymphocyte count comparable with the age-matched controls (> or =3000 microl). Regardless of the total lymphocyte count the NBS patients showed: (1) profound deficiency of CD4+ and CD3/CD8+ T cell subsets and up to fourfold increase in natural killer (NK) cells, almost lack of naive CD4+ T cells expressing CD45RA isoform, unchanged percentage of naive CD8+ cell subset (CD8/CD45RA+) but bearing the CD8 receptor of low density (CD8low); (2) normal expression of CD45RA isoform in the CD56+ lymphocyte subset, profound decrease in alpha beta but up to threefold increase in gamma delta-T cell-receptor (TCR)-positive T cells; (3) shift towards the memory phenotype in both CD4+ and CD8+ lymphocyte subpopulations expressing CD45RO isoform (over-expression of CD45RO in terms of both the fluorescence intensity for CD45RO isoform and the number of positive cells); and (4) an increase in fluorescence intensity for the CD45RA isoform in NK cells population. These results indicate either a failure in T cell regeneration in the thymic pathway (deficiency of naive CD4+ cells) and/or more dominant contribution of non-thymic pathways in lymphocyte renewal reflected by an increase in the population of CD4+ and CD8+ memory cells, gamma delta-TCR positive T as well as NK cell subsets.

Reduction of CD45RA isoform expression and decrease in CD4 and CD8 receptor density in lymphocytes of patients with primary biliary cirrhosis.

BACKGROUND: The immunological background of primary biliary cirrhosis (PBC) remains largely obscure. METHODS: Using double colour flow cytometry, we estimated the distribution of functionally different lymphocyte subpopulations in the peripheral blood of 25 PBC patients and 18 controls. We examined: 1) the expression of CD3, CD4, CD8, CD19 and CD56 surface receptors, 2) the distribution of lymphocyte subsets bearing 'naive' (CD45RA+) and 'memory' (CD45RO+) phenotypes in both CD4+ and CD8+ cell populations, 3) the expression of an early activation marker (CD69), 4) the distribution of C1.7 mAb binding cytotoxic effectors in CD3+, CD8+ and CD56+ cells. The surface marker expression was evaluated in terms of percentage of positive cells and receptor density. RESULTS: We found: 1) a decrease in the percentage of total CD3+ and CD4+ cells, an unchanged proportion of CD8+ cells but elevated proportion of CD19+ cells and NK lymphocytes; 2) a reduction in the percentage of 'naive' CD4+ but normal proportion of 'naive' CD8+ as well as CD4+ and CD8+ 'memory' cell subsets; 3) a decrease in the density of CD4 and CD8 receptors in the subsets of 'naive' and 'memory' T cells, 4) an increase in the percentage of CD69 receptor bearing T cells but unchanged proportion of C1.7 mAb. CONCLUSIONS: It is concluded that the reduction in number of 'suppressor-inducer-like 'naive' CD4+ T-cell subsets in association with the decrease in fluorescence intensity for CD4 and CD8 may significantly contribute to the mechanisms that could account for a development of PBC.

Reduction of CD45RA Isoform Expression and Decrease in CD4 and CD8 Receptor Density in Lymphocytes of Patients with Primary Biliary Cirrhosis.

BACKGROUND: The immunological background of primary biliary cirrhosis (PBC) remains largely obscure. METHODS: Using double colour flow cytometry, we estimated the distribution of functionally different lymphocyte subpopulations in the peripheral blood of 25 PBC patients and 18 controls. We examined: 1) the expression of CD3, CD4, CD8, CD 19 and CD56 surface receptors, 2) the distribution of lymphocyte subsets bearing 'naive' (CD45RA+) and 'memory' (CD45RO+) phenotypes in both CD4+ and CD8+ cell populations, 3) the expression of an early activation marker (CD69), 4) the distribution of C1.7 mAb binding cytotoxic effectors in CD3+, CD8+ and CD56+ cells. The surface marker expression was evaluated in terms of percentage of positive cells and receptor density. RESULTS: We found: 1) a decrease in the percentage of total CD3+ and CD4+ cells, an unchanged proportion of CD8+ cells but elevated proportion of CD 19+ cells and NK lymphocytes; 2) a reduction in the percentage of 'naive' CD4+ but normal proportion of 'naive' CD8+ as well as CD4+ and CD8+ 'memory' cell subsets; 3) a decrease in the density of CD4 and CD8 receptors in the subsets of 'naive' and 'memory' T cells, 4) an increase in the percentage of CD69 receptor bearing T cells but unchanged proportion of C1.7 mAb. CONCLUSIONS: It is concluded that the reduction in number of 'suppressor-inducer-like 'naive' CD4+ T-cell subsets in association with the decrease in fluorescence intensity for CD4 and CD8 may significantly contribute to the mechanisms that could account for a development of PBC.

Heterogeneity of humoral immune abnormalities in children with Nijmegen breakage syndrome: an 8-year follow-up study in a single centre.

During an 8-year period of observation, defects of immune responses were characterized and monitored in 40 of 50 Polish children with Nijmegen breakage syndrome referred to the Children's Memorial Health Institute in Warsaw. The following parameters were determined at diagnosis: (1) concentrations of serum IgM, IgG, IgA; (2) concentrations of IgG subclasses; and (3) lymphocyte subpopulations. In addition, naturally acquired specific antibodies against Streptococcus pneumoniae were determined in 20 patients with a history of recurrent respiratory infections. During follow-up, total serum immunoglobulins and IgG subclasses were monitored systematically in 17 patients who did not receive immunomodulatory therapy. Moreover, anti-HBs antibody response was measured after vaccination of 20 children against HBV. We found that the immune deficiency in NBS is profound, highly variable, with a tendency to progress over time. Systematic monitoring of the humoral response, despite good clinical condition, is essential for early medical intervention.

Primary resistance to clarithromycin in clinical strains of Helicobacter pylori isolated from children in Poland.

Helicobacter pylori resistance to clarithromycin is an important factor in the failure of eradication therapy. The resistance results from point mutations in the 23S rRNA gene of H. pylori. The prevalence of primary resistance of H. pylori to clarithromycin in children and mutations associated with resistance were studied and it was found that 23.5% (23/98) of H. pylori strains isolated in our hospital during 1998-2000 were resistant to clarithromycin. The primary resistance was mainly caused by an A2143G mutation, but the isolates with an A2142G mutation had higher MICs for clarithromycin compared with those with an A2143G mutation: median MIC 256 versus 16 mg/l. Comparison of our data with previous results showed that the prevalence of H. pylori resistance to clarithromycin in children has increased in Poland over the last three years, however the difference was not significant (23.5 vs. 17%, P=0.22).

Antibody responses to preS components after immunization of children with low doses of BioHepB.

BioHepB is a recombinant, hepatitis B vaccine derived from a mammalian cell line and containing HBs as well as preS1 and preS2 antigens, in their glycosylated and non-glycosylated forms. The vaccine was administered intramuscularly to 18 children aged 5 months to 11 years at 0, 1 and 6 months. One hundred percent seroconversion and seroprotection rates were achieved after primary and secondary immunization with the 2.5 microg doses of BioHepB. Ten out of the 18 children (56%) responded with the appearance of anti-preS1 and/or anti-preS2 antibodies in circulation, when analyzed 1, 2, 6, 7 and 12 months after the initiation of vaccination. In comparison with the emergence of the anti-HBs response, early (month 2, after two injections) or late (month 7, after three injections) peak responses were noted for the kinetics of anti-preS1 and anti-preS2 production during the course of immunization, demonstrating that the anti-preS1 and anti-preS2 responses are differently regulated, compared with the anti-HBs response. At month 6, just prior to the final injection, BioHepB caused significantly higher anti-HBs responses (GMT) in preS1-reactive children than in children without preS1 antibodies (P<0.005). Moreover, a significantly higher, anti-HBs response in GMT was also noted for anti-preS2-reactive children compared with anti-preS2-negative children (P<0.05). These findings demonstrated that recognition of the preS epitopes contained in the experimental preS1/preS2/S vaccine is accompanied by a more rapid onset and pronounced antibody response to the S-gene-derived protein in healthy children.

Deficiency of the expression of CD45RA isoform of CD45 common leukocyte antigen in CD4+ T lymphocytes in children with infantile cholestasis.

The immunological background of the pathological changes that appear in infantile cholestasis (infections, inflammatory process in the liver) is largely unknown. With the use of double color flow cytometry, we assessed the distribution of functionally different lymphocyte subpopulations in the peripheral blood of 29 infants with extra and intra-hepatic cholestasis (12 and 17 patients, respectively), aged from 1 to 8.6 months. Control group consisted of 15 age-matched, healthy infants. We examined: (1) the expression of CD3, CD4, CD8, CD19 lymphocyte surface receptors; and (2) the distribution of lymphocyte subsets with distinctive surface Ag characteristics of 'naive' (CD45RA+) and 'memory' (CD45RO+) cells in both CD4+ and CD8+ cell populations. The surface markers expression was evaluated in terms of percentage of positive cells and receptor density. The following changes in the expression of lymphocyte surface markers are described: (1) a decrease in the percentage of total CD3+, CD4+ cells but normal percentage of CD8+ cells and elevated proportion of CD19+ B cells; (2) a reduction of the proportion of 'naive' CD4+ lymphocytes but normal percentage of 'naive' CD8+ as well as 'memory' CD4+ and CD8+ cell subsets; (3) a decrease in density of CD3, CD4+, CD8 receptors, and D45RA isoform in a subset of 'naive' CD4+ cells. We conclude that deficiency of 'naive' CD4+ T cell subset which possess important effector and immunoregulatory functions, and low expression of certain lymphocyte receptors known to be engaged in T cell activation, possibly reflect a defect of cell mediated immunity that may account for viral and bacterial infections, often observed in infants with cholestasis.

Immunological abnormalities in children with biliary atresia.

Since orthotopic liver transplantation is the treatment of choice for bilary atresia, the role of nutritional support preceding this procedure is significant. The aim of this study was to assess the selected parameters of both humoral and cellular immunity before and after nutritional support. Eight children aged 1.08-7 years. with biliary atresia, qualified to LTx, received high-calorie standard diet supplemented with MCT oil. The distribution of functionally different lymphocyte subpopulations in the peripheral blood was evaluated using double color flow cytometry (EPICS-MCL, Coulter). The concentrations of total serum immunoglobulins were measured by nephelometry (Beckman Array 360) and concentrations of IgG subclasses by ELISA. Abnormalities in the expression of lymphocyte surface markers as well as in immunoglobulin synthesis were as follows: 1) decrease in the percentage of total CD3+ (4/8), CD4+ (5/8), CD8+ (3/8) cells and markedly elevated percentage of CD19+ B cells (4/8); 2) reduction of the proportion of 'naive' CD4+ and CD8+ lymphocytes but normal percentage of 'memory' CD4+ and CD8+ cell subsets; 3) hypergammaglobulinemia with especially high levels of IgG (16.0-3.05 g/l) and IgA (2.6-6.66 g/l) was found in 6 out of 8 children. Treatment with hypercaloric diet did not improve the immunological parameters. We conclude that lymphopenia and possibly also hypergammaglobulinemia observed in BA children resulted mainly from the deficiency of the so-called 'naive', suppressor-inducer CD4+ T cell subset (CD4+/CD45RA+) that is known to maintain the proper level of immunoglobulin synthesis by inhibition of B cell differentiation into plasma cells.

IgG subclass distribution of hepatitis B surface antigen antibodies induced in children with chronic hepatitis B infection after interferon-alpha therapy.

The IgG subclass distribution of antibody to hepatitis B surface antigen (anti-HBs) was investigated in 19 children with chronic active hepatitis B infection who showed a complete serological seroconversion after interferon-alpha therapy. Determinations were done 6 and 12 months after treatment. Our results showed no selectivity in anti-HBs synthesis among IgG subclasses. All 4 IgG isotypes were involved in the response, with similar percentage contributions, on average, of IgG1 (35%), IgG3 (27%), and IgG4 (28%), followed by IgG2 (10%). IgG4 became the second most dominant isotype at the end of observation. These results are in contrast to those found after natural seroconversion, in which anti-HBs was highly restricted to neutralizing IgG1 and IgG3, with only a minor contribution from IgG2 and IgG4. It is postulated that analysis of the specific profiles of IgG subclasses may be of value for the estimation of the therapeutic efficacy of recombinant interferon-alpha used and may be helpful in choosing more-effective treatment.

The IgG subclass profile of anti-HBs response in vaccinated children and children seroconverted after natural infection.

The IgG subclass profiles of anti-HBs antibodies were investigated in 30 children who had recovered from acute hepatitis B and 40 children vaccinated against hepatitis B virus (HBV) with Engerix B. After natural seroconversion the mean geometric value of anti-HBs titres was ca 41-fold lower than at the peak of response in vaccinees, and specific antibodies were highly restricted to IgG1 subclass followed by IgG3 with only a minor contribution of IgG2 and IgG4. Conversely, in children immunized with recombinant HBsAg, IgG1 and IgG3 dominated after two doses of vaccine and 1 month after the third injection but the response was less selective and more variable. One year after vaccination IgG4 anti-HBs antibodies became the second dominating isotype. Significant statistical differences in the profiles of IgG anti-HBs were observed when the age and maturity of humoral response were considered. While children vaccinated below 5 years of age responded mainly with IgG1 and IgG3 subclasses, older children (> 5 years) showed a high individual variability in the specific profiles with a high contribution of IgG4. We concluded that vaccination at a younger age leads to the production of antibody subclasses which are more effective for virus neutralization.

[Angioedema is caused by a defect in C1-inhibitor synthesis]. / Obrzek naczynioruchowy zalezny od defektu syntezy C1-inhibitora.

Deficit of the first component of complement inhibitor (C1-inhibitor, C1-inh) may clinically be manifested as angioedema. The disease is characterized by episodic swellings of mucosa and subcutaneous tissue at different locations of the body. Laryngeal swelling can be life-threatening. The major mediators of edema are discussed to be bradykinin and C2b derived peptides. These mediators increase capillary permeability. Antifibrinolytic agents (aminocaproic acid, tranexamic acid) and attenuated androgens (danazol or stanazolol) are used for prophylaxis. Prolonged use both of them might result in more or less severe side effects. In experiments in vitro it has been shown that IFN-gamma, IL-1, IL-6 have a stimulatory effect on C1-inh synthesis. We want to verify the practical use of probiotics as natural inductors of IFN-gamma synthesis for elevating C1-inh level.

Effect of Pseudomonas aeruginosa exotoxin A on IFN-gamma synthesis: expression of costimulatory molecules on monocytes and activity of NK cells.

The aim of the study was (1) to evaluate the effect of Pseudomonas aeruginosa Exotoxin A (P-ExA) on the production of IFN-gamma in anti-CD3 induced human peripheral blood mononuclear cells (PBMC) and (2) to establish the effect of P-ExA on the IFN-gamma dependent cellular activities such as the expression of costimulatory molecules on monocytes and cytotoxicity of NK cells. The toxin in a high dose (100 ng/ml) inhibited IFN-gamma synthesis. Inhibitory effect of P-ExA was abolished by IL-1alpha which in a combination with P-ExA exerted a strong synergistic effect on IFN-gamma synthesis. Other monokines such as IL-1beta, IL-6, TNF-alpha neither reversed the inhibitory effect of P-ExA nor induced production of IFN-gamma. P-ExA also inhibited IFN-gamma-induced cellular events: (1) expression of costimulatory molecules on monocytes (CD80, CD86, ICAM-1, HLA-DR); (2) cytotoxic activity of NK cells. Inhibition of NK cells activity by P-ExA was not reversed by cytokines such as IL-2, IFN-alpha and TNF-alpha, which are known to enhance effector functions of NK cells. From these results we conclude that: (1) inhibition of IFN-gamma synthesis, as well as IFN-gamma-induced expression of costimulatory molecules and NK-cell effector functions may lead to suppression of specific and non-specific defense mechanisms, respectively, which are necessary for elimination of PA bacteria; (2) enhancement of IFN-gamma synthesis induced by P-ExA in a combination with IL-1alpha may cause harmful, Th1 cells dependent, inflammatory reactions of the host (septic shock, tissue damage) during infection with Pseudomonas aeruginosa.

Immunology of Helicobacter pylori infection.

We have tried to answer several questions in this article, dealing with: ontogenesis of the immune response, presentation of H. pylori antigens to immune cells, systemic vs local immune response, cytokine Th1/Th2 configuration, the role of cytokines, especially represented during H. pylori infection, mimicry phenomena, extragastroduodenal sites and manifestations and finally, vaccine development. The new achievements in the vaccine field, also of Polish groups, were underlined.

Report from the International Symposium on viral hepatitis, 24-25 October 1997, Warsaw, Poland.

The authors present the results of an International Symposium on 'Viral Hepatitis', held in Warsaw on 24-25 October 1997 and dedicated to the scientific activity of Professor Adam Nowoslawski, the founder of the Polish school of Immunopathology, with many contributions to the viral hepatitis research. The symposium was divided into main sessions and poster reports which covered most of the topics in this field. This successful meeting has gathered many distinguished speakers from different countries and was attended by ca. 350 participants, mainly from Poland, but also from the neighbouring countries.

Kabuki (Niikawa-Kuroki) syndrome associated with immunodeficiency.

We report a case of a 19-year-old male with the cardinal features of the Kabuki syndrome (KS) and, in addition, with severe immunodeficiency. Finding immune deficiency in a KS patient, prompted us to determine whether this association was related to a deletion within the DiGeorge chromosomal region. Fluorescence in situ hybridization (FISH) with the Oncor probe N25(D22S75) revealed no deletion of 22q11.2 in the patient.

Effect of Pseudomonas aeruginosa exotoxin A on CD3-induced human T-cell activation.

The effect of Pseudomonas aeruginosa (PA) exotoxin A (P-ExA) on CD3-induced T-cell activation was studied on the level of T-cells (proliferation, synthesis of interleukin (IL)-2, expression of IL-2R complex, ICAM-1,2 and LFA-1 molecules), and on the level of monocytes (expression of ICAM-1,2, LFA-1 molecules, as well as FcRI and CD14 receptors). We found that: (1) P-ExA blocked T-cell proliferation and this effect was totally reversed by intact monocytes, and partially by IL-2 or TPA but not by costimulatory cytokines (IL-1alpha, IL-1beta, TNF-alpha or IL-6); (2) P-ExA transiently, in short-term cultures (48 h), inhibited synthesis of IL-2; (3) prolonged stimulation (96 h) of peripheral blood mononuclear cells (PBMC) or CD4 + T-cells with P-ExA in high or low doses (100 and 10 ng/ml, respectively), enhanced the level of IL-2 in the cultures; (4) P-ExA at low dose, combined with IL-1beta, TNF-alpha or IL-6, up-regulated synthesis of IL-2; and (5) stimulation of T-cells with anti-CD3 monoclonal antibody (mAb) and P-ExA at high dose diminished the expression of the p55 chain but not of the p75 chain of IL-2R complex and slightly affected the expression of CD3 complex, ICAM-1,2 and LFA-1 molecules. Hence, P-ExA can regulate the level of IL-2 in cultures of CD3-induced T-cells either by inhibition of IL-2 consumption (when P-ExA is applied in high dose), or by induction of IL-2 production (a costimulatory effect exerted by P-ExA in low dose in combination with monokines). Action of P-ExA on monocytes resulted in: (1) inhibition of the expression of ICAM-1,2 molecules and their ligand LFA-1 molecule; (2) low expression of FcRI receptor (a ligand for Fc part of CD3 mAb); and (3) inhibition (over 90%) of the expression of CD14 molecule. In conclusion, P-ExA-induced anergy of T-cells depends on: (a) decrease in the affinity of IL-2R complex on activated T-cells; and (b) inhibition of the accessory activities of monocytes.

[Vaccination against hepatitis B in children with chronic hematologic diseases treated with immunosuppression]. / Szczepienia przeciw wirusowemu zapaleniu watroby typu B u dzieci z przewleklymi chorobami krwi leczonych immunosupresyjnie.

Prevention of hepatitis B infection is an important factor in the successful management of cancer and aplastic anaemia cases. Our result suggested that children with Hodgkin's disease and solid tumors vaccinated during early stage of immunosuppressive therapy are good responders to hepatitis B vaccine. Active immunisation with hepatitis B vaccine (Engerix B), was also effective in children with leukaemia after completing immunosuppressive therapy. Protective levels of antibodies remained 6 years after vaccination. Vaccination according to shortened schedule (0-10-20 days) was not effective in these children. Passive immunisation is indicated in children with chronic neoplastic haematological diseases during immunosuppressive therapy. In 6 children the lack of seroconversion after vaccination was due to immune disorders.

Serum and salivary antigliadin antibodies and serum IgA anti-endomysium antibodies as a screening test for coeliac disease.

Serum and salivary IgA and IgG antigliadin antibodies were determined by an enzyme-linked immunosorbent assay in 18 children with villous atrophy and 30 children on a gluten-free diet for coeliac disease in whom normal intestinal mucosa was found. Serum IgA anti-endomysium antibodies were also determined by an immunofluorescence method in these children. Serum IgG antigliadin and IgA anti-endomysium antibodies had the highest sensitivity (100 and 94.4%, respectively), followed by serum IgA antibodies to gliadin (72.2%), salivary IgA antigliadin (61.2%) and IgG antigliadin (50%) antibodies. The highest specificity was found for serum IgA anti-endomysium (100%) and IgA antigliadin (96.6%) antibodies and salivary IgA and IgG antigliadin antibodies (93.3%), while serum IgG antigliadin antibodies were found to be least specific (63.3%).

[Deficiency of C2 component in a 9-year old girl]. / Deficyt skladnika C2 dopelniacza u 9-letniej dziewczynki.

The authors describe a 9 year-old girl with homozygous deficiency of C2 component, causing null activity of the classical pathway of complement. The girl suffered from several recurrent infections since birth, later developed signs of the Henoch-Schönlein disease. At the age of 1 1/2 years she was hospitalized due-to bacterial meningitis, most probably of Neisseria meningitis etiology.

[Perspectives of developing a vaccine against hepatitis C virus]. / Perspektywy opracowania szczepionki przeciw wirusowemu zapaleniu watroby typu C.

The aim of this paper is to present current data on active prophylaxis against hepatitis C virus (HCV). Vaccines against HAV and HBV (also HDV, because this virus can only exist when HBV infection is present) have been made and are already widely used. Unfortunately, no vaccine against HCV has been developed yet. HCV structure, replication, experiments with recombinant vaccines on chimpanzees as well as some subjects concerning gene vaccines and implications for prophylaxis of HCV infection are described.