After chemotherapy,functional humoral response capacity is restored before complete restoration of lymphoid compartments

Chemotherapy has, besides the beneficial effects, several adverse effects. Suppression of the immune system is one of the most important problems. Infections caused by encapsulated bacteria like Streptococcus pneumoniae are responsible for a major part of infectious problems during and after treatment. The splenic marginal zone is essential in the initiation of an immune response to encapsulated bacteria. In this study, we analysed the effects of three different cytostatic agents on humoral immune responses. We found a reduced, but detectable immune response capacity at two days after treatment although the marginal zone B cell population is severely reduced at this time point. Twenty-four days after cessation of treatment, the immune response capacity was largely restored although lymphoid compartments were still not completely restored at that time point. Apparently, the presence of only few marginal zone B cells is sufficient to evoke a rise in antibody titres and although antibody titre increases are low, even small rises are most likely clinically relevant.     

Assessment of local cellular immunity in lung cancer by bronchoalveolar lavage

Summary Small cell lung cancer (SCLC) is the most malignant of the pulmonary neoplasms and is associated with a poor local cellular immune response. 16 patients with non small cell lung cancer (NSCLC) and 11 patients with SCLC underwent bronchoalveolar lavage (BAL) in the lung which harbored the tumor in order to investigate the lymphocyte surface antigens utilizing the immunoperoxidase technique. Analysis of blood lymphocytes was performed in parallel. 8 patients with previous sarcoidosis in complete remission who underwent BAL and 10 normal blood donors served as controls.Among blood lymphocytes the CD3⁺, CD4⁺ and CD16⁺ cell populations were elevated significantly and the T4/T8 ratio was elevated in NSCLC patients, but only CD16⁺ were augmented in SCLC. Cell populations expressing the activation markers transferrin (TF) receptor, interleukin-2 (IL-2) receptor and the very late antigen VAL-1 were also increased in NSCLC, while SCLC was associated with antigen distributions similar to controls. No differences between the cohorts were seen in the expression of human leukocyte antigen (HLA)-DR. In BAL the population of CD3⁺ and CD4⁺ cells were reduced in SCLC and the T4/T8 ratio was diminished in contrast to controls and NSCLC patients, whereas these two latter groups did not differ from each other. The distribution pattern of CD16, TF receptor and IL-2 receptor in the study groups resembled that of cells of the blood stream, but CD16⁺ natural killer cells were additionally down regulated to control values in SCLC. No differences were seen in the distribution of VLA-1. HLA-DR⁺ cells were clearly elevated in both cancer groups.In general NSCLC was associated with a shift to higher relative numbers of immunocompetent and activated cells. This was most probably attributable to an immune response to neoplastic growth. This shift was largely lacking in SCLC. The analysis of lymphocytes from the periphery of the target organ emerged as a sensitive tool for the study of cellular immunity in lung cancer and showed many similarities to circulating blood cells. However, the analysis of natural killer cells and HLA-DR suggested a dissection of cellular immune response between blood and lung in pulmonary cancer. A depressive interaction between the tumor and the cellular host immune response may contribute to the exceptional malignancy of SCLC.Abbreviations BAL bronchoalveolar lavage - HLA-DR human leukocyte antigen-DR - IL-2 interleukin-2 - NSCLC non small cell lung cancer - SCLC small cell lung cancer - TF transferrin - VLA-1 very late antigen-1     

Balloon cell nevus of the soft palate: an immunohistochemical and ultrastructural study

An ultrastructural analysis of oral balloon cell nevus of intramucosal type complemented with an immunohistochemical study was performed for the first time. The lesion was composed of large balloon cells with an admixture of small nevus cells and melanophages at the periphery. Balloon cells showed cytoplasmic accumulation of vacuoles of varying sizes and the presence of microgranular and vacuolated melanosomes were found. Residual cytoplasm contained no identifiable organelles. A spectrum of transitional forms between balloon cells and conventional nevus cells with microvacuoles was readily observed. Both cells exhibited intense immunoreactivity to multiple melanocytic markers. Ballooning phenomenon was not evident in melanophages containing a large amount of melanosome complex. It can be inferred, from the present and previous observations, that progressive vacuolization of melanosomes in nevomelanocytes may be responsible for the formation of peculiar ballooning appearance, suggesting an aberrant melanogenesis.     

Changes in Streptococcus pneumoniae serotypes causing invasive disease with non-universal vaccination coverage of the seven-valent conjugate vaccine

The pneumococcal seven-valent conjugate vaccine (PCV7) has been administered in Portugal since late 2001 through the private sector. To evaluate the impact of PCV7 use, the serotypes and antimicrobial susceptibility of pneumococci causing invasive disease in Portugal during 2003–2005 were determined and compared with available data for the period 1999–2002. Changes in serotype distribution compatible with the introduction of PCV7 were shown for children ≤5 years of age from 2003 onwards and for adults from 2004 onwards. PCV7 use with coverage of 43% of children with four doses in the 2004 birth cohort, although substantially below universal coverage, seems to have contributed to greatly reducing the proportion of invasive infections due to vaccine serotypes  4, 6B, 14 and 23F. Similarly, significant indirect effects on the serotype distribution of pneumococci causing infections in adults were noted, with reductions in the proportion of invasive infections caused by serotypes  4, 5 and 14. These changes were accompanied by an increase in the proportion of two non-vaccine serotypes: 19A isolates in all age groups and 7F isolates in adults. Whereas serotypes  6B, 14 and 19A were associated with multidrug resistance, isolates expressing serotypes  4 and 7F were fully susceptible for the most part. There were no changes in the proportion of resistant isolates within each serotype and, in spite of the changes in serotype prevalence, there was not an overall reduction in the proportion of infections caused by resistant pneumococci.     

近红外信息辐照对免疫抑制大鼠体液免疫功能的影响

本实验观察了近红外信息辐照(辐照)对免疫抑制大鼠体液免疫功能的调整作用。取大鼠54只随机分为三组:甲组各鼠腹腔注射环磷酰胺(CY,75mg/kg)和伤寒沙门氏菌鞭毛抗原(HAg,7×10~8菌体/只),同时各鼠每天全身辐照1h,共4周;乙组腹腔注射CY和HAg丙组仅腹腔注射HAg。结果甲、乙、丙三组于第四周末的存活率分别为83.3％、38.1％和66.7％(甲与乙组比较P<0.05);第四周末血清总IgG含量分别为141.4±17.6U/ml,120.3±16.6U/ml和117.0±22.9U/ml(甲组与其它两组比较P<0.01);第二周末抗H抗体效价分别为1:91.9、1:46.6和1:149.3(甲与乙组比较P<0.05;乙与丙组比较P<0.01)。结果表明,辐照对免疫功能低下的机体有增强免疫功能的作用。     

Study on nonspecific immunity in pregnant women: II. Effect of hormones on chemiluminescence response of peripheral blood phagocytes.

To analyze the mechanisms of increased nonspecific immunity in pregnant women, the effect of various hormones on the phagocytic activity was estimated by a luminol-dependent chemiluminescence (CL) response during phagocytosing opsonized zymosan. The CL response of whole blood supplemented with exogenous human chorionic gonadotropin (hCG) increased significantly in all the male and female subjects and pregnant women. An approximate two- to fourfold increase was observed in comparison with the unsupplemented control in each subject at concentrations ranging from 1 to 1,000 IU/ml after 48 h of incubation (P less than 0.05). Progesterone slightly stimulated the CL response in female subjects only, but had no effect on male and pregnant women. Estradiol (E2) did not stimulate the CL response in any subject. The expression of Fc and C3b receptors on the surface of polymorphonuclear leucocytes (PMNL) in pregnant women was also investigated by measuring the immunofluorescence stained with monoclonal antibody to Fc and C3b receptors, respectively. The relative numbers of Fc receptors increased significantly in the third trimester compared to those of female control (P less than 0.05). Those of C3b receptor also increased in the second and third trimester (P less than 0.005). These results suggested that the nonspecific immunity represented by phagocytic activity in pregnant women increased with both oxidative metabolic responsiveness and the expression of membrane receptors. Besides, the increased phagocytic activity of the maternal host is probably due to the stimulatory effect of both endogenous and exogenous hCG on their peripheral blood phagocytes.     

Melanosomes and MHC class II antigen-processing compartments

Melanosomes are specialized intracellular compartments within melanocytes and retinal pigment epithelial cells that function in the synthesis, storage, and secretion of melanins, which are the major pigments made by mammals. The mechanisms that regulate the formation of melanosomes, and the pathways by which constituent proteins are targeted to them, are related to those involved in the biogenesis of major histocompatibility complex (MHC) class II antigen-processing compartments. Consequently, diseases that affect pigmentation may also affect antigen presentation to T cells. Moreover, many of the tissue-specific proteins that localize to melanosomes and participate in melanin formation double as tumor-associated antigens that are targets for T cells in patients with melanoma. Our studies on melanosome biogenesis are providing new ways of thinking about antigen-processing compartments and the mechanisms regulating presentation of tumor-associated antigens.