Influences of the cellular and humoral immune system in bronchoalveolar lavage on lung function in pulmonary sarcoidosis.

We investigated the changes in the cellular and humoral immune system in bronchoalveolar lavage (BAL) performed in 22 patients with pulmonary sarcoidosis and in 14 normal control subjects and their interactions with lung function parameters. Lymphocytosis, the increase in OKT4+ lymphocytes and OKT4+OKDR+ lymphocytes correlated with the increase in immunoglobulins, especially IgG, IgA and kappa chain assembled immunoglobulins. The transferrin levels obtained in BAL were found to be higher in patients with sarcoidosis, and they correlated with the cellular and, more closely, with other humoral findings. A negative correlation existed between the ventilatory parameters and the cell count and humoral findings. In addition, we found a negative correlation between the diffusing capacity for carbon monoxide and other cellular findings, which was most pronounced with reference to lymphocytes, OKT4+ lymphocytes and the OKT4+/OKT8+ ratio. These results underscore the role of OKT4+ lymphocytes, activated OKT4+OKDR+ lymphocytes and transferrin in the increase in immunoglobulins, mainly kappa chain isotypes. Because of the relationship between these changes and ventilatory parameters, and the diffusing capacity, the above results also reveal the clinical relevance of our findings.     

Comparative evidence for a link between Peyer's patch development and susceptibility to transmissible spongiform encephalopathies

Background  

Epidemiological analyses indicate that the age distribution of natural cases of transmissible spongiform encephalopathies (TSEs) reflect age-related risk of infection, however, the underlying mechanisms remain poorly understood. Using a comparative approach, we tested the hypothesis that, there is a significant correlation between risk of infection for scrapie, bovine spongiform encephalopathy (BSE) and variant CJD (vCJD), and the development of lymphoid tissue in the gut.     

HIV-1 neutralization: mechanisms and relevance to vaccine design

Antibody (Ab) mediated neutralization is a crucial means of host resistance to many pathogens and will most likely be required in the development of a vaccine to protect against HIV-1. Here we examine mechanistic aspects of HIV-1 neutralization with attention to recent studies on the stoichiometric, kinetic and thermodynamic parameters involved. Neutralization of HIV-1, as with any microbe, minimally requires an initial molecular encounter with Ab. Ab occupancy of functional heterotrimers of the envelope glycoproteins, gp120 and gp41 (Env), indeed appears to be the dominant mechanism of neutralization for HIV-1. However, the Ab-binding site, the parameters mentioned above, as well as the stages and duration of vulnerability to Ab recognition, prior to and leading up to viral entry, each have a distinct impact on the mechanism of neutralization for any given Ab specificity. With HIV-1, the problems of mutational variation and neutralization resistance, coupled with the lability and conformational heterogeneity in Env, have stimulated the search for rational approaches to Env immunogen design that are unprecedented in vaccinology.     

Immunophenotypic identification of possible therapeutic targets in paediatric non-Hodgkin lymphomas: a children's oncology group report

Immunophenotypic analysis can identify protein epitopes in non-Hodgkin lymphomas (NHL) that may respond to targeted immunotherapies, such as anti-CD20 and anti-CD52. Recent studies suggest additional targets may provide therapeutic benefits in NHL. This study evaluated protein expression of CD25, CD52, CD74 and CD80 in paediatric NHL to determine possible targets for immune-based therapeutic approaches. Patient samples were derived from paediatric NHL clinical trials sponsored by the Children's Cancer Group (CCG, now the Children's Oncology Group, COG) and included Burkitt lymphoma (BL), diffuse large B-cell lymphoma (DLBCL), disseminated T- and B-cell lymphoblastic lymphoma (T-LBL and B-LBL) and anaplastic large cell (ALCL). Immunophenotypic studies were performed on formalin-fixed, paraffin-embedded diagnostic tissues. CD25 was expressed in 8% of T-LBL and 75% of ALCL cases, but not in BL, DLBCL, or B-LBL. CD52 was expressed in 99% of cases of paediatric NHL of all subtypes. CD74 was expressed in 100% of B-LBL, BL and DLBCL, but was absent in ALCL and T-LBL. CD80 was expressed in 12% of B-LBL, 6% of BL and 10% of DLBCL cases studied, but was not detected in T-cell NHL. These expression patterns suggest that CD25, CD52 and CD74 may represent potential new therapeutic targets in paediatric NHL.     

Establishment and characterization of a human myeloid cell line from Philadelphia chromosome-negative myeloblastic leukemia arising in a patient with myelodysplastic syndrome

A new hematopoietic cell line derived from a patient with Philadelphia chromosome (Ph1)-negative myeloblastic leukemia arising from a form of myelodysplastic syndrome (MDS) is described. This cell line, designated TMM, consists of immature cells with the morphological characteristics of young myeloblasts and grows in suspension culture with a doubling time of about 30 hours. By cytochemical analysis the cultured cells were positive for acid phosphatase. They were free of the Epstein-Barr virus-associated nuclear antigen as well as terminal deoxynucleotidyl transferase. Further phenotypic analysis revealed the expression of the myelomonocytic-specific antigen Leu-M1 and receptors for the Fc portion of IgG. Partial differentiation of these cells could be induced by dimethyl sulfoxide, tetradecanoyl phorbol acetate, or hypoxanthine and resulted in cells of the myeloid series expressing lysozyme and receptors for the C3b complement protein. The karyotype was 46,XY, lacked the Ph1 chromosome, and displayed no abnormalities at the light microscopic level. No rearrangement of the bcr-c-abl gene complex was found. This cell line should be useful for studying an important type of the heterogeneous population constituting Ph1-negative myeloblastic leukemia, arising in this instance from MDS, as well as for studying differentiation and proliferation of human pluripotent stem cells.     

Cabergoline and prolactinomas: lack of association between <Emphasis Type="Italic">DRD2</Emphasis> polymorphisms and response to treatment

Background

About 80% of prolactinomas respond to dopamine agonists (DA) with hormonal normalization and tumor shrinkage. Mechanisms of DA resistance include reduction of dopamine receptor subtype 2 (DRD2) expression, short and long isoform ratio and post-receptor mechanisms. It was suggested that polymorphisms in the gene encoding dopamine receptor subtype 2 gene (DRD2) could be associated with variable effectiveness of cabergoline (CAB).

Objective

To assess the influence of DRD2 polymorphisms in responsiveness of CAB treatment in patients with prolactinoma.

Study design and patients

Cross-sectional retrospective case–control study analyzing the frequency of five DRD2 polymorphisms in 148 patients with prolactinoma and 349 healthy subjects. The association of genetic variants and clinical characteristics with CAB responsiveness was performed in 118 patients (mean age at diagnosis 29 years; range 11–61 years) with hormonal evaluation. Patients with prolactin (PRL) normalization were considered as responders.

Results

No association in genotypes and allele proportions was found comparing patients and controls. On pharmacogenetic study, 118 patients on CAB were included and 20% were non-responders. No association was found between clinical characteristics (gender, age, PRL level and tumor size at diagnosis) and polymorphisms of DRD2 with CAB responsiveness. Otherwise, there was association between polymorphisms rs1076560 (allele A) and rs1800497 (allele T) and the presence of macroadenomas.

Conclusion

No correlation was found between DRD2 polymorphisms and CAB responsiveness in patients with prolactinoma. More data are necessary in order to assess the influence of DRD2 genotyping on DA treatment response.