Cryptosporidium spp. infection is usually self-limited in immunocompetent hosts but can be severe and life threatening in children and in immunocompromised individuals including those with primary or ...acquired immunodeficiencies. One hundred and three faecal samples were collected from 35 hospitalised patients with different symptoms and tested for the presence of the parasite. Cryptosporidium oocysts were found in four of 35 patients (11.4%) using Ziehl-Neelsen staining of faecal smears and immunofluorescence assay, whereas 12 (34.3%) samples tested positive by nested polymerase chain reaction assay. Cryptosporidium DNA was detected in one bile sample but not in a liver tissue biopsy sample collected from a patient who suffered from sclerosing cholangitis. Sequence analysis of oocyst wall protein and beta-tubulin gene fragments revealed three different parasite species (Cryptosporidium hominis, Cryptosporidium meleagridis and Cryptosporidium parvum) in children with primary immunodeficiencies, whereas only C. parvum was found in immunocompetent individuals and in those with secondary immunodeficiencies. This study has revealed a high prevalence of Cryptosporidium infection in hospitalised patients in Poland and confirmed that molecular techniques enable a more sensitive detection of the parasite.
V(D)J rearrangement in lymphoid cells involves repair of double-strand breaks (DSBs) through non-homologous end joining (NHEJ). Defects in this process lead to increased radiosensitivity and severe ...combined immunodeficiency (RS-SCID). Here, a SCID patient, M3, is described with a T
−B
+NK
+ phenotype but without causative mutations in CD3δ, ɛ, ζ or IL7Rα, genes specifically involved in T cell development. Clonogenic survival of M3 fibroblasts showed an increased sensitivity to the DSB-inducing agents ionizing radiation and bleomycin, as well as the crosslinking compound, mitomycin C. We did not observe inactivating mutations in known NHEJ genes and results of various DSB-repair assays in G
1 M3 cells were indistinguishable from those obtained with normal cells. However, we found increased chromosomal radiosensitivity at the G
2 phase of the cell cycle. Checkpoint analysis indicated functional G
1/S and intra-S checkpoints after irradiation but impaired activation of the “early” G
2/M checkpoint. Together these results indicate a novel class of RS-SCID patients characterized by the specific absence of T lymphocytes and associated with defects in G
2-specific DSB repair. The pronounced G
2/M radiosensitivity of the RS-SCID patient described here, suggests a defect in a putative novel and uncharacterized factor involved in cellular DNA damage responses and T cell development.
V(D)J rearrangement in lymphoid cells involves repair of double-strand breaks (DSBs) through non-homologous end joining (NHEJ). Defects in this process lead to increased radiosensitivity and severe ...combined immunodeficiency (RS-SCID). Here, a SCID patient, M3, is described with a T(-)B(+)NK(+) phenotype but without causative mutations in CD3delta, epsilon, zeta or IL7Ralpha, genes specifically involved in T cell development. Clonogenic survival of M3 fibroblasts showed an increased sensitivity to the DSB-inducing agents ionizing radiation and bleomycin, as well as the crosslinking compound, mitomycin C. We did not observe inactivating mutations in known NHEJ genes and results of various DSB-repair assays in G(1) M3 cells were indistinguishable from those obtained with normal cells. However, we found increased chromosomal radiosensitivity at the G(2) phase of the cell cycle. Checkpoint analysis indicated functional G(1)/S and intra-S checkpoints after irradiation but impaired activation of the "early" G(2)/M checkpoint. Together these results indicate a novel class of RS-SCID patients characterized by the specific absence of T lymphocytes and associated with defects in G(2)-specific DSB repair. The pronounced G(2)/M radiosensitivity of the RS-SCID patient described here, suggests a defect in a putative novel and uncharacterized factor involved in cellular DNA damage responses and T cell development.
V(D)J rearrangement in lymphoid cells involves repair of double-strand breaks (DSBs) through non-homologous end joining (NHEJ). Defects in this process lead to increased radiosensitivity and severe ...combined immunodeficiency (RS-SCID). Here, a SCID patient, M3, is described with a TaB+NK+ phenotype but without causative mutations in CD3I, E>, I or IL7Ra, genes specifically involved in T cell development. Clonogenic survival of M3 fibroblasts showed an increased sensitivity to the DSB-inducing agents ionizing radiation and bleomycin, as well as the crosslinking compound, mitomycin C. We did not observe inactivating mutations in known NHEJ genes and results of various DSB-repair assays in G1 M3 cells were indistinguishable from those obtained with normal cells. However, we found increased chromosomal radiosensitivity at the G2 phase of the cell cycle. Checkpoint analysis indicated functional G1/S and intra-S checkpoints after irradiation but impaired activation of the "early" G2/M checkpoint. Together these results indicate a novel class of RS-SCID patients characterized by the specific absence of T lymphocytes and associated with defects in G2-specific DSB repair. The pronounced G2/M radiosensitivity of the RS-SCID patient described here, suggests a defect in a putative novel and uncharacterized factor involved in cellular DNA damage responses and T cell development.
The Paediatric Expert Group on the Immunization Programme was established in January 2007. It is an independent advisory body to the Minister of Health. The Expert Group consists of paediatricians ...from various sub-specialities. Most of them are members of the Polish Society of Vaccinology (Table I). The Group started their activities informally in 2005. The first project concerned changes in immunization against tuberculosis and prophylaxis of measles, mumps and rubella. The project was fully implemented in 2006. The changes initiated three years ago, gradually implemented in the Immunization Programme are a result of wide cooperation with the Ministry of Health, Department of Health Policy Chief Sanitory Inspector, as well as the Institute of Tuberculosis and Pulmonary Diseases. The aim of the Paediatric Expert Group on the Immunization Programme is to present a unified policy in matters related to vaccination, leading to rapid changes in the prophylaxis of infective diseases which are still a threat to the life and health of children.
In coculture experiments with normal lymphocytes, peripheral blood lymphocytes (PBL) of 10 boys with hypogammaglobulinemia were screened for the presence of cells able to suppress Pokeweed mitogen ...(PWM)- and Staphylococcus aureus Cowan I-induced immunoglobulin production in vitro. PBL and T lymphocytes of two patients were shown to suppress reproducibly PWM-induced immunoglobulin production of control PBL and of control B + T lymphocytes. PBL of three other patients were also able to suppress but their activity was expressed only in combination with some but not other normal lymphocytes. In neither case was the Cowan I-induced response suppressed. PBL and T lymphocytes of one other patient were able to suppress both PWM- and S. aureus Cowan I-induced immunoglobulin production of normal lymphocytes. These data provide evidence for two functionally distinct suppressor T lymphocytes in hypogammaglobulinemic patients.
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