Pharmacological immunomodulation of surgical trauma.

Surgery and accidental trauma induce changes in the immune response, showing a predominant pattern of activation through the Th2 cell pathway to the detriment of Th1 cell pathway activation. Anapsos is a hydrosoluble extract obtained from Polypodium leucotomos. Anapsos has shown immunomodulating effects in vitro. On a rat experimental model (tibia and fibula fracture), cytokines (interleukin [IL]-2, IL-4, IL-6, IL-10, and IL-12) (enzyme-linked immunosorbent assay, ELISA) and cell percentages of CD4, CD8 CD25, CD122, and CD132 (monoclonal antibodies, MoAb) were determined in peripheral blood 7 days before surgery (PRE), 1 day after surgery (1PO), and 7 days after surgery (7PO). On postoperative day 1, rats undergoing fracture show an increase of CD8 percent expression and IL-6 and IL-10 levels, in contrast to rats undergoing fracture plus anapsos treatment. On postoperative day 7, rats undergoing fracture show an increase of IL-6 levels, whereas rats undergoing fracture plus anapsos do not. The IL-12 level decreases on postoperative day 7 in the group with fracture but not in the fracture plus anapsos group. Thus, we conclude that anapsos is able to modulate the immune response after trauma, inhibiting Th2 pathway activation with no effect on Th1 pathway activation. In trauma, Anapsos could prevent the shifting Th1/Th2 balance.

Generation of rabbit antibodies against death ligands by cDNA immunization.

Specificity problems, especially in immunoblot analysis, have been shown for several commercial antibodies raised against the death ligand Fas ligand (FasL) using conventional protein and/or peptide immunizations. In this work, we have optimized the development of rabbit antisera and isolated pAb against the death ligands FasL, Apo2 ligand/TRAIL and Apo3 ligand/TWEAK by cDNA intramuscular immunization. This alternative approach has generated specific pAb in all three cases, which are useful for immunoblot purposes. The present data suggest that for the production of antibodies against certain glycosylated membrane proteins, cDNA immunization could be the method of choice.

Role of caspases and apoptosis-inducing factor (AIF) in cladribine-induced apoptosis of B cell chronic lymphocytic leukemia.

We have evaluated the role of caspases and the mitochondrial apoptosis inducing-factor (AIF) in apoptosis induced by cladribine (2CdA), in vitro, in cells from patients of B-CLL and in peripheral blood lymphocytes from normal donors. In sensitive B-CLL cells, apoptosis was characterized by cell shrinking, loss of mitochondrial membrane potential (DeltaPsi(m)), phosphatidylserine exposure, activation of caspases 3, 7, 8 and 9, reduction of Mcl-1 levels, translocation of AIF from mitochondria to nucleus and chromatin condensation. No significant variations in the levels of Bcl-2, Bax and Bak proteins were noticed upon treatment with 2CdA. Co-treatment of cells with the pan-caspase inhibitor Z-VAD-fmk attenuated some morphological and biochemical characteristics of apoptosis and delayed 2CdA-induced DeltaPsi(m) loss, but did not prevent cell death. Z-VAD-fmk did not prevent 2CdA-induced AIF translocation but in this case apoptotic cells displayed only peripheral chromatin condensation, characteristic of AIF action. Reduced or negligible caspase 3 expression did not prevent 2CdA toxicity in cells from four patients. Cells from three patients that responded poorly to 2CdA lacked expression of caspases 9 or 3. Cells from another patient resistant to 2CdA expressed caspases 3, 7, 8 and 9 but they were not activated by treatment. These results indicate that execution of apoptosis is carried out independently by AIF and caspases, which are responsible for the development of apoptotic phenotype in response to 2CdA. Although caspases can also collaborate in DeltaPsi(m) loss, proapoptotic proteins from the Bcl-2 superfamily may be the key inducers of DeltaPsi(m) loss and apoptosis in B-CLL cells sensitive to 2CdA.

Farnesyltransferase inhibitor BMS-214662 induces apoptosis in B-cell chronic lymphocytic leukemia cells.

B-cell chronic lymphocytic leukemia (B-CLL) cells develop resistance to nucleoside analogs over time. This chemoresistance may be caused by selection for B-CLL cells with defects in the particular apoptosis pathway triggered by these drugs. Therefore, anticancer agents that induce apoptosis through alternative pathways might be useful in treating chemoresistant B-CLL. Farnesyltransferase inhibitors (FTIs) are a class of synthetic drugs with definite molecular targets, which have demonstrated cytotoxicity against leukemic cell lines. We have studied the ex vivo effect of the FTI BMS-214662 on cells from 18 patients with B-CLL. Low concentrations (<1 microM) of BMS-214662 prevented farnesylation of the chaperone marker HDJ-2 and had no effect on Akt activation. BMS-214662 induced apoptosis in B-CLL cells from all patients studied, including those showing resistance to cladribine and fludarabine ex vivo and in vivo. Treatment with BMS-214662 induced loss of mitochondrial membrane potential (DeltaPsi(m)), phosphatidylserine exposure, proapoptotic conformational changes of Bax and Bak, reduction in Mcl-1 levels and activation of caspases 9 and 3. The general caspase inhibitor Z-VAD-fmk did not prevent BMS-214662-induced cell death. These results indicate that BMS-214662 may be a useful drug for treating B-CLL and, in particular, an alternative for the therapy of purine analog-resistant or relapsed B-CLL.

Lymphocyte T subset counts in children with elevated low-density lipoprotein cholesterol levels.

The aim of this study was to determine blood lymphocyte T subset counts in children with elevated levels of low-density lipoprotein cholesterol. We studied 107 children, ages 2.0 to 15.9 years, from 79 families who were referred to our Lipid Research Clinic because total cholesterol serum levels higher than 200 mg/dl had been detected in at least one child. At the time of diagnosis we analyzed serum lipoprotein profile and blood lymphocyte T subsets (CD3, CD4 and CD8). Children were classified according to LDL-C levels into three groups: (1) normal, if levels were between the 5th and 75th percentiles (50 and 125 mg/dl, respectively); (2) at moderate risk, if levels were between the 75th and 95th percentiles (125 and 150 mg/dl, respectively); and (3) at high risk, if levels were above the 95th percentile (150 mg/dl). In children aged 2.0 to 6.9 years, all lymphocyte T subset counts were higher in the high risk group than in the normal group (P < 0.05 and P < 0.01). In children aged 11.0 to 15.9 years, the CD4 subset count was also significantly higher in the high risk group in the other two groups (P < 0.05 and P < 0.01). These results are in agreement with pathologic findings in the atheromatous plaque.

Variation in T helper cell/T cytotoxic-suppressor cell index during cardiac operations.

After surgical procedures, humoral and cell-mediated immunity responses decrease. Both anesthesia and surgical trauma play an important role in this effect. Cardiac operations induce a greater decrease in immunologic response than other surgical operations. On the other hand, identification of functional lymphocyte subclasses by means of appropriate monoclonal antibodies appears to provide an accurate measurement of cellular immune competence. Employing these methods, we found a significant decrease of T helper cell/T cytotoxic-suppressor cell ratio in the periperal blood of 20 patients undergoing cardiac operations. This decrease during the period of anesthesia (before surgical incision) is due as much to a decrease of T helper cell percentage as to an increase of T cytotoxic cell percentage. However, during the surgical trauma period (surgical incision to the end of the operation) it is due to a greater increase of T cytotoxic-suppressor cell percentage without significant changes in the percentage of T helper cells.

Relationship between immunoinflammatory proteins containing sialic acid and low-density lipoprotein serum concentrations.

The aim of this study was to investigate the relationship between sialoglycoproteins and the lipoprotein profile in a group of children with different levels of low-density lipoprotein cholesterol. We have studied 177 children of 132 families who were sent to our Pediatric Lipid Research Clinic because of serum cholesterol concentrations higher than 5.17 mmol/l. At the time of diagnosis, we analyzed the serum lipoprotein profile and the sialoglycoproteins: alpha 1-antitrypsin, acid alpha 1-glycoprotein, haptoglobin, alpha 2-macroglobulin, transferrin, IgA, IgG, IgM, complement C3 component and ceruloplasmin. At 7.0 to 10.9 years, alpha 1-glycoprotein serum concentrations were higher in the high risk group than in the moderate risk group (P < 0.05). At 2.0 to 6.9 years, IgA and IgM serum concentrations were higher in the moderate risk group than in the low risk group (P < 0.05 and P < 0.01, respectively), and IgG and IgM serum concentrations were also higher in the high risk group than in the low risk group (P < 0.05). Our results seems to reflect a general reaction to injury or inflammation which could be associated with the atherosclerotic process.

[The effect of preoperative parenteral nutrition on the capacity of the immune response in malnourished patients (preoperative parenteral nutrition and immunity)]. / Efecto de la nutrición parenteral preoperatoria en la capacidad de respuesta inmune en pacientes desnutridos. (Nutrición parenteral preoperatoria e inmunidad).

The objective of this study is to evaluate the response of the subpopulations of lymphocytes and IGs to the administration of total parenteral nutrition for 7 days in 26 patients suffering from malnutrition, 12 of whom had digestive neoplasia and 14 non-neoplastic gastrointestinal disorders. Following the total parenteral nutrition, a significant increase in the percentage of T-helper lymphocytes was noted, and an improvement in the OKT4/OKT8 quotient, as well as in the IgA and the C4 fraction of the complement. The existence of neoplastic conditions did not have a significant effect on the variations in the parameters studied. The presence of lipids in the parenteral nutrition diet did not affect the subpopulations of lymphocytes.

Dendritic cell uptake of iron-based magnetic nanoparticles.

We have investigated the internalization of magnetic nanoparticles (NPs) into dendritic cells (DCs) in order to assess both the final location of the particles and the viability of the cultured cells. The particles, consisting of a metallic iron core covered with carbon, showed no toxic effects on the DCs and had no effect in their viability. We found that mature DCs are able to incorporate magnetic nanoparticles in a range of size from 10 nm to ca. 200 nm, after 24 h of incubation. We describe a method to separate cells loaded with NPs, and analyze the resulting material by electron microscopy and magnetic measurements. It is found that NPs are internalized in lysosomes, providing a large magnetic signal. Our results suggest that loading DCs with properly functionalized magnetic NPs could be a promising strategy for improved vectorization in cancer diagnosis and treatment.

A study of IgG blocking antibodies in patients affected with respiratory allergy.

The levels of blocking antibodies were studied in 200 patients affected with bronchial asthma and/or allergic extrinsic rhinitis with sensitization to grass pollen and dust mites shown by cutaneous and RAST tests. IgG blocking antibodies were studied using ELISA, in relation to: Immunotherapy treatment duration. The degree of clinical improvement obtained. The conditions, before and after immunotherapy treatment. The conditions, 12-24 months after having completed 3 years of immunotherapy. The results indicate that: A high level of blocking antibodies is reached in the group of patients between 4-7 months of immunotherapy treatment. These patients also reached the stage of the maintenance dosage. There exists a significant and specific response of blocking antibodies in patients treated with specific immunotherapy. There exists a close correlation between symptomatology and the level of blocking antibodies, although this correlation is not perfect. The hyposensitization preparations used did not succeed in maintaining permanently high levels of blocking antibodies once the treatment was completed. ELISA is a good alternative to other more frequently used techniques in measuring blocking antibodies, and it can be used in following patients during the course of immunotherapy.

Lymphocyte T subset counts in children with hypercholesterolemia receiving dietary therapy.

BACKGROUND: In children with hypercholesterolemia, dietary therapy is indicated; however, we do not know if a low-fat diet can modify some organic functions, i.e. immune function. METHODS: 42 children with hypercholesterolemia received a low-fat, low-cholesterol diet during 6 months. At baseline and after the treatment period, we determined a lipoprotein profile and some immune characteristics: immunoglobulins G, A and M; complement components (C3, C4 and factor B), and blood lymphocyte subsets (CD3, CD4 and CD8). RESULTS: Total cholesterol serum concentrations showed a significant reduction after 6 months of dietary therapy (p = 0.008). After 6 months on a low-fat diet, lymphocyte T subset counts (CD3, CD4 and CD8) showed significant decreases (p < 0.01 to p < 0.003), but lymphocyte counts were always within normal ranges. There was also a significant correlation between changes in some lymphocyte T subset counts (CD3 and CD8) and changes in triglyceride serum concentrations (p < 0.05). CONCLUSIONS: A low-fat, low-cholesterol diet diminished CD3, CD4 and CD8 lymphocyte subset counts that are elevated in children with hypercholesterolemia. Dietary therapy, with emphasis on the intake of n-3 fatty acids, could be useful in the modulation of the immune response at the atheromatous plaque level.

Cockroach hypersensitivity in asthmatic patients.

Hypersensitivity to cockroach antigen has been recognized as an important cause of perennial allergic rhinitis and asthma. To assess the frequency of cockroach hypersensitivity in our country, 150 asthmatic atopic subjects were studied using skin testing and in vitro assays for cockroach-specific IgE antibodies (Oriental and German cockroaches). Twenty-two of 61 patients who had a positive history of cockroach exposure had positive skin tests, and only 3 of 89 patients who had no history of exposure had positive skin reactions. Of 25 patients with positive skin tests, 23 showed specific IgE antibodies against oriental and German cockroaches using RAST and EIA techniques. In summary, approximately 15% of asthmatic atopics in Madrid area are sensitive to cockroaches (positive skin test + specific IgE antibodies). These results indicate that cockroach hypersensitivity should be considered in every patient with perennial asthma.

Study of HLA as a predisposing factor and its possible influence on the outcome of multiple sclerosis in the sanitary district of Calatayud, northern Spain.

The relationship between multiple sclerosis (MS) and the HLA antigens DR2 and DQ1 is well recognised, but, in Spain, it has not been clearly defined. The aim of our study was to investigate the relationship between MS and HLA antigens in the sanitary district of Calatayud, northern Spain, and to correlate these antigens with the progression of the disease. Thirty-four patients were selected from a long-term (October 1990 to July 1996) prospective survey in the region where there was a prevalence rate of 58 per 100,000 population. The HLA antigens were determined in 31 patients. A control group of 895 people of Caucasian race was recruited from the same population. We performed serologic tests on all participants. Nucleotide typing was carried out in DR2-positive patients. The most frequent antigens in excess in MS were: A19 (odds ratio, OR: 2.29, p = 0.04), B5 (OR: 2.85, p = 0.02), B41 (OR: 7.65, p = 0.04), CW7 (OR: 3.4, p = 0.004), DR6 (OR: 6.18, p = 0.0001) and DR10 (OR: 3.4, p = 0. 004). The DR2 antigen was also more frequent in MS patients (39%) than in controls (19%; OR: 2.69, p = 0.01). All positive DR2 patients showed the DR15(2) split but not the DR16(2) split. The frequency of antigens CW4 and DR1 was lower in MS patients than in controls. The CW4 antigen was detected in 12% of the patients and in 33% of the controls (OR: 0.28, p = 0.04). The DR1 antigen was found in 20% of the controls and in none of the MS patients (OR: undefined, p = 0.01). The DQ1 antigen was observed in 68% of the patients and in 50% of the controls (OR: 2.1, p = 0.07). We did not find any relationship between HLA antigens and progression of the disease. Although we found that DR2 antigen is linked to MS, we also found other antigens related to the disease. This suggests a genetic heterogeneity in our geographic area. We also concluded that the DR1 antigen may play a protective role, as it was detected in 20% of the controls and in none of the MS cases.

Immune response and in vivo production of cytokines in patients with liver hydatidosis.

Cytokines play an important role in the human immunological response, but the exact role of cytokines in the human immune response against parasites, especially against Echinococcus granulosus, remains unclear. IL-1, IL-2, IL-4 and tumour necrosis factor (TNF) levels in peripheral blood of 21 patients with liver hydatidosis were evaluated before surgical treatment, and the levels of IgA, IgM, IgG, IgE, specific IgE against E. granulosus, C3, C4 and DF complement fractions and CD20, CD3, CD4, CD8 and CD16 cell percentages were also determined, as was the relationship between these variables and cytokine levels. Data from hydatid patients were compared with data obtained from 21 healthy volunteers. Hydatid patients showed increases of IgG, IgE, IgEs and IL-2 (P < 0.01), and decreases of IL-1 and TNF levels (P < 0.001), but these variables (respectively) increased in patients showing cysts in the central area of the liver or with a wide opening of cysts in the biliary tract. The increase of IL-1, IL-2 and IL-4 showed a close relationship with the number, characteristics and above all the location of cysts within the liver itself. IgG and IL-4 levels and also IgG and IgE levels showed a significant correlation (P < 0.05).