Interference of prolactin on some processes of nonspecific immunity.
Explore the source record for details and available documents.
Animals↗
Biomedical subjects
I Nuzzo
Publications and source records attributed to I Nuzzo.
Autoreactive cytotoxic cells in rabbits after prolonged immunostimulation.
Rabbits immunized for 6 months with different amounts of sterile human serum showed weight loss and a decrease in leukocytes. The lymphocyte population reacting to ConA contained autoreactive cells capable of causing 51Cr release from labeled cells from a culture consisting of splenic and peripheral lymphocytic cells from the same animal.
Animals↗
Iak antigen and interleukin-1 secretion by lymphocytes and monocytes of mice fed a lipid-rich diet.
Female mice were maintained on a lipid-rich diet. After 33 days, the mice showed a decrease in the cell population bearing MHC class II molecules, and in the production of interleukin-1 (IL-1). After 60 days, we reported a further decrease of the cell population with MHC class II molecules and the secretion IL-1.
Animals↗
Correlation between modification of membrane phospholipids and some biological activity of lymphocytes, neutrophils and macrophages.
Our study considered the possibility of modifying the functional response of human neutrophils, of mouse lymphocytes and macrophages treated with phospholipids having different polar groups, different isomerisms with saturated and unsaturated fatty acids from C12 to C20 carbon atoms. The results are as follows. a) Most of the phospholipids containing fatty acids from C12 to C20 cause inhibition of the blastogenic capacity of the polyclonal activators tested. b) The phospholipids tested cause a decrease in adherence of polymorphonuclear leukocytes with the exception of the phosphatidyl-choline containing saturated and unsaturated fatty acids. c) A decrease in polymorphonuclear leukocytes migrational capacity almost always occurs. d) The cells treated with L-phosphatidyl-ethanolamine having fatty acids from C14 to C17 show an increase in chemiluminescence; those treated with phosphatidyl-choline and L-phosphatidyl-glycerol show a decrease of the chemiluminescence; L-phosphatidic acid and L-phosphatidyl-ethanolamine having Microbial fatty acids (FAs) at C16 cause a decrease in the formation of phagolisosomes in the macrophages tested.
Animals↗
Further characterization of the impaired protective function in mice fed with lipid diet.
Female mice were maintained on lipid diet for 20 days. The nonspecific and immunological defense capability was determined by in vitro and in vivo methods. It was found that mice held mostly on a lipid diet demonstrate an all-round lowered response. Following 20 days of lipid diet the splenocytes exhibit: (1) an inversed lipid-protein ratio; (2) an inability to respond to sheep erythrocytes; (3) a reduction in [3H] thymidine incorporation in splenocytes stimulated with lipopolysaccharide (LPS) or with concanavalin A; (4) a reduction in the number of cells bearing surface immunoglobulins in splenocytes stimulated with LPS; (5) an inhibition of phagocytosis and intracellular killing in macrophages; (6) a lowering in granulocyte chemotaxis and adherence capacity; (7) a higher mortality to LPS after loading with galactosamine; and (8) a lowered complement activity even following LPS activation.
Animals↗
Phagocytosis of bacterial aggregates by granulocytes.
A study was conducted on the granulocytic phagocytosis of bacterial aggregates obtained under ideal environmental conditions. For the strains studied, aggregation was favored by low salt concentrations, low pH and temperatures between 30 degrees C and 40 degrees C. Our results show that the phagocytic capacity of granulocytes depends on the type and size of these aggregates. Those formed by a smaller number of cells are more easily phagocytized than the larger ones.
Animals↗
Toxicity in uremia. 2. Correlation between PTH levels and impaired aspecific immunity.
The role of PTH in depressing polynuclear leucocyte (PMN) phagocytosis in uremia was investigated. The hydrophobicity and phagocytic activity of normal PMN was tested in presence of uremic patients' serum with low (Group A) or high (Group B) levels of plasma PTH. The PMN phagocytic index was lowered by serum of both groups, but more in presence of Group B serum (p A vs B less than 0.002). Similarly, the contact angle of cells was affected more in presence of serum of patients with high PTH levels (p B vs A less than 0.003; p B vs C less than 0.002).
Cytotoxins↗
Surface properties of Escherichia coli strains responsible for urinary infections.
Many studies shown that the capacity of the bacteria to adhere to the host cells is a fundamental requisite to the onset of any colonization process and hence infection. Our results shown that E. coli strains from patients with recurring urinary tract infections showed a high degree of surface hydrophobicity, correlated with the presence of numerous fimbriae with respect to a control group.
Antigens, Bacterial↗
Phagocytosis of bacteria after exposure to macrophages or lymphocytes.
In our present study we have examined the phagocytosis by polynucleates towards bacteria exposed to macrophages or lymphocytes. Our results show that for almost all the bacterial strains, the contact with lymphocytes determines changes in hydrophobicity correlated to variations in the possibility of being phagocytized and of more significant intracellular killing with respect to bacteria treated with macrophages.
Animals↗
Phagocytosis and resistance to Salmonella typhimurium infection in mice fed with lipidic diet.
The peritoneal macrophages from mice on a lipidic diet have shown an increase of surface hydrophobicity of cytoplasmatic membrane. This fact is correlated with a decrease of the phagocytic index and with an impairment of Salmonella typhimurium.
Animals↗
Cytotoxic antibody dependent cells in mice experimentally infected with Brucella abortus.
In this study we investigated the cytotoxic activity mediated by antibody dependent cells (K cell) in C57BL/6 mice experimentally infected with Brucella abortus. The involvement of the K cells in experimental infection from Brucella was studied by evaluating the bacteriolysis in the presence of specific antibodies. After 3 h of incubation, approximately 30 +/- 3% of the labeled Brucellae undergo lysis, whereas the presence of lymphocytic populations alone, or of a specific decomplemented serum, determines a lysis of 5 +/- 3%. Cytotoxic antibody dependent activity of purified lymphomonocytic populations (ADCC) evaluated against cells labeled with 51Cr sensitized with specific antibodies obtained from mice is considerably increased in mice experimentally infected with Brucellae with respect to that present in non-infected mice. The increased activity begins to manifest itself 5 to 7 days after inoculation of the Brucellae reaching a maximum on the 10th day. The same results were obtained in the lymphocytic populations prepared from normal animals and those infected by Brucellae searching for K cells with the ability to form rosettes (EA-RFC).
Animals↗
Phagocytosis in diabetic subjects: increase in hydrophobicity of granulocyte cytoplasmic membrane.
Granulocytes from diabetic subjects have impaired ability to engulf bacteria; the data obtained suggest that the alterations are correlated with an increase in surface hydrophobicity, as measured by contact angle.
Adult↗
[New alo-, nitro-, and alonitro- derivatives of o-hydroxybenzanilide and their antimicrobial activity].
Explore the source record for details and available documents.
Escherichia coli↗
Immunological response in mice after long-term stimulation with cell wall antigens from Brucella melitensis.
The continuous stimulation of the immune system using cell wall antigens from Brucella melitensis was found to cause both quantitative and qualitative changes in circulating lymphocyte populations in mice. Animals were inoculated in the hind legs with antigens on alternate days for varying lengths of time. During a two-month period, we saw a higher number of circulating lymphocytes, with an increase in the number of CD4+ cells (L3T4+) and B lymphocytes (I-Ad). After two months, a drop in the overall number of circulating lymphocytes occurred, with a decrease in CD4+ cells and an increase in CD8+ cells. During the first two months, we observed a size increase in popliteal lymph nodes and an elevated humoral response. The response then waned with the declining CD4+ cells. In the first two months, the treated animals also showed an in vitro response to two mitogens, concanavalin A and lipopolysaccharide and to the cell wall fraction, after which the treated animals showed a decreased response.
Animals↗
Th1-Th2 response in hyperprolactinemic mice infected with Salmonella enterica serovar Typhimurium.
Prolactin (PRL) is a pituitary hormone and a cytokine known to regulate several physiological functions. It plays a role in modulating the immune system of rodents and humans. A hormonal protection against listeria and salmonella infections has been previously ascribed to effects of PRL on immunocompetent cells. Here, the role of PRL in the Th1-Th2 response was evaluated based on the pattern of cytokines release by splenocytes from hyperprolactinemic mice infected with Salmonella enterica serovar Typhimurium. Hyperprolactinemia by pituitary graft reduced the number of bacteria in spleens of in vivo infected mice. Modulation of Th1 (IFN-gamma, IL-12) and Th2 (IL-4, IL-10) cytokine production by splenic cells was found. Our results indicate that PRL can up-regulate IFN-c and IL-12 secretion in response to salmonella infection, confirming its in vivo immunostimulatory effect and suggesting hormonal participation in the genesis and sustenance of the Th1 response.
Animals↗
[Changes in the surface structure of bacteria treated with antibiotics (cephalosporins, aminoglycosides].
Explore the source record for details and available documents.
Aminoglycosides↗
[Effect of various antibiotics on the surface hydrophobicity of bacterial cells].
Explore the source record for details and available documents.
Bacteria↗