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At least 595 records · Page 33Linked to original sources
PubMed1986

Studies on cellular immunity against bile proteins in primary biliary cirrhosis by the leukocyte migration inhibition test (microdroplet method).

Cellular immunity against human bile proteins was investigated by the leukocyte migration inhibition test (LMIT) with 13 primary biliary cirrhosis (PBC) patients, 10 chronic aggressive hepatitis (CAH) patients and 21 healthy adults. Hepatic bile taken from patients operated on for lithiasis of the biliary tract was fractionated into five fractions with Sepharose 6B gel. A subtoxic dose of each fraction was determined in the healthy adults, and used as the antigen for LMIT. Out of the 5 fractions, only the third fraction led to an LMIT positive response in 8 out of 11 (73%) PBC patients and in 1 out of 10 (10%) CAH patients. The difference between PBC and CAH was significant (p less than 0.005). The remaining 3 PBC patients with LMIT negative responses were all under D-penicillamine treatment. Antibody to each fraction was prepared in rabbits. Using the antibodies after absorption with human serum, the localization of the antigens which were present in each fraction was investigated immunohistochemically using human liver sections. The antigen to the anti-first fraction antibody was detected specifically in the epithelial cells of the bile ducts and the ductules, and the antigen to the anti-third fraction antibody was detected specifically on the membrane of the bile canalicules. The third fraction was fractionated into three fractions by Sephadex G-200 gel. Only the first of the 3 fractions showed an LMIT positive response in 3 PBC patients, and its molecular weight was determined to be about 500,000. It is concluded that PBC patients develop cellular immunity against canalicular-antigen-containing fractions but not ductal-antigen-containing ones.

Antigens↗
PubMed2000

Interleukin-10 blockade corrects impaired in vitro cellular immune responses of systemic lupus erythematosus patients.

OBJECTIVE: Many systemic lupus erythematosus (SLE) patients display impaired cellular immune responses against allo- or recall antigens. Given the down-regulating properties of interleukin-10 (IL-10) on antigen-presenting cell functions, this study was undertaken to investigate whether the well-known overproduction of IL-10 by SLE peripheral blood mononuclear cells (PBMC) was involved in this process. METHODS: We measured the proliferation of SLE or control PBMC against irradiated allogeneic dendritic cells in the absence or presence of antibodies blocking IL-10 activity, or in the absence or presence of IL-12. RESULTS: As a group, SLE PBMC proliferated against allogeneic targets less than control PBMC. However, SLE patients could be categorized as good responders or poor responders according to the amplitude of their allogeneic response. Interestingly, serum IL-10 concentrations were significantly higher in the poor responders than in the good responders or in the controls, and addition of antibodies blocking IL-10 activity significantly increased the proliferative responses of the group. We confirmed the role of IL-10 in the impaired allogeneic responses displayed by SLE PBMC by demonstrating that addition of IL-10-containing SLE PBMC supernatants inhibited a normal allogeneic response between unrelated healthy controls, and by showing that this inhibitory effect was commensurate with the concentrations of IL-10 measured in the supernatants. In this experimental setting, we also demonstrated that IL-10-containing SLE PBMC supernatants inhibited IL-12 p35 and IL-12 p40 gene expression. Consistent with the last observation, we found that addition of exogenous IL-12 restored the proliferation of poor-responder SLE patients' PBMC. CONCLUSION: Taken together, these results indicate that dysregulation of the IL-10/IL-12 balance plays a critical role in the impaired cellular immune responses observed in SLE patients.

Adolescent↗
PubMed1996

Nonspecific modification of cellular immunity by Yersinia enterocolitica.

An isogenic pair of virulent and avirulent Yersinia enterocolitica O9 strains was used to examine the influence of the virulence plasmid on the non-specific modification of the cellular immunity in BALB/c mice after experimental infection with yersiniae. The modification of contact hypersensitivity response to dinitrofluorobenzene, resistance to the syngeneic lymphoma LSTRA, and resistance to Listeria monocytogenes was heavily influenced by the presence of the virulence plasmid. As a general rule for the modification of cellular immunity by yersiniae, the plasmid-bearing strain induced a short-term suppression followed by a potentiation, whereas the isogenic plasmid-less derivative induced only a short-term potentiation. The Yersinia-mediated enhancement of cellular immunity resulted in protection against infection with Listeria and partial protection against LSTRA transplantation. Results of Concanavalin A-induced proliferation of splenocytes from Yersinia-infected mice suggested a role for cytokines as gamma-interferon in the Yersinia-mediated immunopotentiation.

Animals↗
PubMed1987

Cellular immunity to nucleocapsid and pre-S determinants in asymptomatic carriers of hepatitis B virus.

Previous studies of cellular immunity in asymptomatic HBV carriers have been limited to evaluation of responses to plasma-derived HBsAg preparations. We have explored the specificity of cellular immune responses to HBV antigens in these subjects using an indirect T-lymphocyte migration inhibitory factor assay and three antigen preparations (recombinant nucleocapsid antigen (HBcAg), plasma-derived HBsAg with or without pre-S2, and Saccharomyces cerevisiae-synthesized HBsAg without pre-S2 region). T cells from 10 asymptomatic chronic HBV carriers with normal liver function tests were responsive to nucleocapside determinants (mean migration index = 0.55 +/- SD 0.07) and to pre-S2-positive plasma-derived HBsAg (MI = 0.62 +/- 0.05). However, none responded to HBsAg devoid of pre-S2 sequences (MI = 0.98 +/- 0.04). In further experiments, T cells from three HBV carriers, cultured with six different HBsAg preparations, exhibited responsiveness only to those preparations containing significant pre-S2 activities. Our results show that T-cell immunity to nucleocapsid determinants of the virus and HBsAg in present in asymptomatic HBV carriers; the latter is restricted to antigenic preparations containing significant pre-S2 activities. Hence, T-cell immunity to pre-S determinants may not always be associated with HBV clearance.

Adolescent↗
PubMed1986

Limiting dilution analyses for the quantification of cellular immune responses in bovine ostertagiasis.

A sensitive limiting dilution analysis (LDA) was used to quantitate the local and systemic cellular immune response of cattle after immunization with keyhole limpet hemocyanin (KLH) and infection with Ostertagia ostertagi. The assay measures the proliferative response of bovine T-cells after in vitro stimulation with antigen. Interleukin 2 activity was supplied by supernates from mitogen-stimulated bovine peripheral blood lymphocytes (PBL) and accessory cell function was in the form of irradiated autologous PBL. The assay measures the response of a single cell and was most easily demonstrated in the lymph nodes draining the site of antigen inoculation. Comparison of cell frequencies and maximal responses generated in conventional proliferative assays showed several differences between the two assays. First, after antigen injection, the highest cell frequencies were seen in the draining lymph nodes within 3 days, and decreased by 10 days post-immunization. In contrast, in mass cultures maximal stimulation was not seen until 7-10 days after injection, but remained high up to 4 weeks after immunization. Second, at 17 days post-infection, a time of eruption of the parasite from the gastric glands, high frequencies of inducible cells were demonstrated by LDA in all lymphoid populations tested. In contrast, low levels of proliferation were seen in mass cultures. The reasons for these differences may include different sensitivities to suppression or more stringent requirements for specificity between the two assays. Finally, it was found that immunologically naive calves have relatively high frequencies of Ostertagia-specific cells in PBL, and that after infection these frequencies decrease. These results indicate either active suppression of the potential anti-Ostertagia response or an extra-vascularization of these cells to the site of infection.

Animals↗
PubMed1998

Impact of preexisting and induced humoral and cellular immune responses in an adenovirus-based gene therapy phase I clinical trial for localized mesothelioma.

Little is known about the immune responses induced by recombinant adenoviral (Ad) vectors in humans. The humoral and cellular immune responses were therefore analyzed in 21 patients with localized malignancy (mesothelioma), who received intrapleurally high doses of a replication-defective Ad5 vector carrying a suicide gene. Eight of 21 patients had pretreatment titers of neutralizing antibodies (NAb) to Ad at > or =1:100. Peripheral blood mononuclear cells (PBMCs) proliferated in response to adenoviral 5 structural proteins before treatment in 17 of 21 patients. Preexisting humoral and cellular immunity did not preclude gene transfer. Vector instillation induced high titers of nonneutralizing and neutralizing anti-Ad antibody (4- to 341-fold increase in 18 of 20 patients) in a dose-dependent manner. Three patients generated antibodies to the transgene, herpes simplex virus thymidine kinase. Ad5-specific proliferation of PBMCs increased significantly (>3-fold) after vector administration in 12 of 21 patients in a dose-dependent manner. Thus, replication-defective Ad5 administered intrapleurally induced significant humoral and cellular immune responses that induced no obvious adverse clinical sequelae.

Adenoviridae↗
PubMed2000

Branched-chain amino acid-enriched diet: effects on insulin secretion and cellular immune aggression.

Several reports have demonstrated that high-protein diets may have beneficial effects on experimental models of diabetes and have raised the possibility that branched-chain amino acids could play a role in these protective effects. We investigated the effect of a normoproteic, branched-chain amino acid-enriched diet (experimental diet) on insulin secretion from C57BL/6N mice transferred with splenocytes from diabetic syngeneic donors. Mice previously fed with the experimental or control diet received three intraperitoneal injections, every other day, of 5 x 107 viable mononuclear splenocytes obtained from control or diabetic donors. Results showed that mice fed with the experimental diet and transferred with "diabetic" splenocytes presented: i) normoglycemia, and (ii) significantly higher levels in both phases of glucose-induced insulin secretion and normal values of arginine-glucose-induced insulin secretion. To evaluate the in vitro cellular immune aggression, dispersed mouse islet cells were co-cultured with splenocytes from syngeneic diabetic mice. First, dispersed islet cells from mice on the experimental or control diet were co-cultured with splenocytes from control or diabetic mice on a commercial diet. In the presence of "diabetic splenocytes, dispersed islet cells from mice on the experimental diet presented a significantly lower in vitro cellular immune aggression. On the other hand, "diabetic" splenocytes from mice fed with the experimental diet produced a significantly reduced cellular immune aggression on dispersed islet cells. Our results showed that feeding branched-chain amino acids increased the capacity of beta cells to withstand a functional assault and diminished the extent of in vitro cellular immune aggression.

Amino Acids, Branched-Chain↗
PubMed1986

Reduced cellular immunity to varicella zoster virus during treatment for acute lymphoblastic leukemia of childhood: in vitro studies of possible mechanisms.

To determine the effect of antileukemic therapy on preexisting immunity to varicella zoster virus, we studied 20 children with acute lymphoblastic leukemia maintained in complete continuous remission for greater than 1 year. Cellular immunity was tested by lymphocyte proliferation in response to varicella antigen. Antiviral antibody was measured using the fluorescent antibody to membrane antigen technique. Reduced lymphocyte proliferation was found in 9 of 16 seropositive patients when compared to an age-related control group. On the other hand, antibody titers in patients receiving chemotherapy remained positive and were essentially unchanged from pretreatment values. Shingles occurred in two of nine children with diminished and none of seven patients with normal cellular immunity, suggesting that proliferative responses to varicella antigen may have predicative value in identifying patients at risk for viral reactivation. Additional studies were done to determine if defective antigen presentation or reduced lymphocyte responder-cell frequency could account for the subnormal proliferative responses. Intact presentation of varicella antigens by patient mononuclear cells to parental, virus-specific T-cell blasts suggested that antigen processing was not defective. However, varicella-specific responder-cell frequencies measured by limiting dilution analysis were found to be depressed in most patients, including some with normal proliferative responses. Our findings indicate that therapy for acute lymphoblastic leukemia in children can be associated with depressed cell-mediated immunity to varicella zoster virus even though patients remain seropositive. Further studies suggest that while monocyte-mediated antigen presentation remains intact, virus-specific lymphocyte numbers decline and probably contribute to decreased cellular immunity to varicella zoster virus in children being treated for leukemia.

Adult↗
PubMed1986

Modulation of cellular immunity in medical students.

This study assessed the psychosocial modulation of cellular immunity in 34 medical-student volunteers. The first blood sample was obtained 1 month before examinations, and the second on the day of examinations. There were significant declines in the percentage of helper/inducer T-lymphocytes, in the helper/inducer-suppressor/cytotoxic-cell ratio, and in natural killer-cell activity in the blood samples obtained on the day of examinations. Half of the subjects were randomly assigned to a relaxation group which met between sample points; the frequency of relaxation practice was a significant predictor of the percentages of helper/inducer cells in the examination sample. Three biochemical nutritional assays (albumin, transferrin, and total iron-binding protein) were within normal limits on both samples. Data from the Brief Symptom Inventory showed significantly increased global self-rated distress associated with examinations in the no-intervention group, compared to nonsignificant change in the relaxation group. Clinical and theoretical implications are discussed.

Adult↗
PubMed1987

Cellular immunity in patients with systemic juvenile rheumatoid arthritis.

We studied the cellular immune responses in 10 patients with systemic form of juvenile rheumatoid arthritis. The numbers of peripheral T lymphocytes and their helper/inducer and cytotoxic/suppressor subpopulation were within normal levels. Activated T lymphocytes (DR+) were slightly increased but not at statistically significant levels. In contrast to the T cells, B lymphocytes were increased; both the percentage of B cells (B1+) and the number of cells spontaneously secreting IgG, IgA, and IgM were increased. Stimulation of peripheral mononuclear cells in vitro with pokeweed mitogen induced poor plaque-forming cell responses, which were partially improved upon removal of monocytes. The presence of concanavalin A in the cultures led to complete suppression. We conclude that patients with systemic JRA are characterized primarily by B-cell rather than T-cell abnormalities.

Adolescent↗
PubMed1995

Cellular immunity to the P6 outer membrane protein of nontypeable Haemophilus influenzae.

Cellular immunity to nontypeable Haemophilus influenzae in a population of 10 healthy, immune adults was determined by measuring lymphocyte blast transformation and antibody secretion in response to the P6 outer membrane protein. P6 (200 microliters/ml) induced lymphocyte blast transformation that peaked on day 10 of incubation. The peak induction of antibody-secreting cells occurred on day 8 of incubation. In comparison with the response to tetanus toxoid stimulation, the peak lymphocyte blast transformation response to P6 was reduced (mean counts per minute +/- standard error of the mean [SEM], 3,457 +/- 503 versus 9,414 +/- 1,464; P = 0.0051) and delayed (mean days +/- SEM, 10.3 +/- 0.4 versus 8.4 +/- 0.5; P = 0.0169); however, P6 was a better stimulus of antibody secretion from lymphocytes, particularly antibody of the immunoglobulin M (IgM) class (mean peak numbers of antibody-secreting cells per 10(5) peripheral blood mononuclear cells +/- SEM: IgG, 85 +/- 29 versus 42 +/- 16 [P = 0.0469]; IgM, 81 +/- 20 versus 25 +/- 7 [P = 0.0125]; IgA, 24 +/- 8 versus 16 +/- 6 [P = 0.0526]). Thus, lymphocytes from immune individuals recognize P6 of nontypeable H. influenzae as an immunogen. These data provide a basis for future studies with otitis-prone children who fail to develop a normal antibody response to P6 antigen (N. Yamanaka and H. Faden, J. Pediatr. 122:212-218, 1993).

Adult↗
PubMed1992

Cellular immunity to cartilage proteoglycans: relevance to the pathogenesis of ankylosing spondylitis.

Cellular immunity to cartilage proteoglycans may be responsible for sustaining chronic inflammation in ankylosing spondylitis. This hypothesis was examined by measuring peripheral blood and synovial fluid mononuclear cell proliferation in five preparations of human cartilage proteoglycan monomer in vitro. Peripheral blood mononuclear cells from 25 patients and synovial fluid mononuclear cells from five patients were compared with those from normal and disease control subjects matched for age. No significant differences were found between the three groups. This suggests that autoimmune responses to cartilage proteoglycans are unlikely to play a significant part in the pathogenesis of ankylosing spondylitis.

Adult↗
PubMedDate not supplied

[Cellular immunity in two familial cases of thyroid carcinoma (author's transl)].

Cellular immunity in two brothers with thyroid carcinoma in a family presenting pathological thyroid changes is investigated. In these brothers a low PHA lymphocyte blast-transformation and an elevated number of surface membrane Ig bearing lymphocytes were observed. These data are discussed in relation to the question of immunological defects which frequently are present in carcinoma patients.

Adolescent↗
PubMed1989

[Monoclonal antibodies OKT4 and OKT8 in the evaluation of cellular immunity in children with recurrent bronchitis].

The study aimed at evaluating cellular immunity in children with recurrent bronchitis with the aid of T-cells evaluation with rosette test and their subpopulations with monoclonal antibodies. The study involved 50 children aged between 2 and 14 years and 30 healthy children. Significant decrease in the absolute number and percentage of T-cells was seen in children with recurrent bronchitis. This decrease seemed apparent and probably resulted from the changes in receptors for sheep erythrocytes. Determination of T-cells subpopulation were within normal values as well as helper T-cells and suppressor T-cells ratio.

Adolescent↗
PubMed1986

[Cellular immune response in HIV(LAV/HTLV-III) infection].

Various tests to determine the cellular immune response in HIV infected persons are presented and their use in clinical practice is discussed. The T4 cell count using the full blood method is a precise test for evaluation of T4 cell elimination by HIV infection and the immune deficiency thus developing. The skin test to various recall antigens (multitest) is simple and helpful in confirming a suspected immune defect. It is, however, too insensitive to detect incipient T4 cell destruction without functional consequences. The lymphocyte count is diminished in final disease stages only and is not helpful in discriminating between early disease stages. Proliferative tests of isolated lymphocytes are of prognostic relevance if antigen is used as a stimulus, since diminution of antigen induced proliferation is a sensitive parameter of immune dysfunction. The value of mitogen induced proliferations lies in possible comparison of the effect of autologous or control serum on proliferative response, since immunosuppressive factors may be found in sera of HIV infected persons.

AIDS-Related Complex↗
PubMed1993

[Abnormalities of cellular immunity in uremic patients].

In order to clarify the abnormalities of cellular immune responses in uremic patients, we studied several immunological parameters such as T cell subsets, the number of B cells, in vitro immunoglobulin production by peripheral blood mononuclear cells (PBMC) with or without addition of pokeweed mitogen or IL-2 in 19 patients on chronic hemodialysis (HD), 42 patients on continuous ambulatory peritoneal dialysis (CAPD) and 27 healthy volunteers. The CD4/CD8 ratio was significantly higher in HD and CAPD patients than in the control group. Higher activated T cell counts (T cells with DR antigen and IL-2R) were observed in the patient groups than in normal controls. The number of DR + T cells showed a positive correlation with the level of serum beta 2 MG in patient groups. Spontaneous synthesis of immunoglobulin in vitro in mononuclear cell culture was observed in all groups in the following order; control, CAPD and HD. The number of B cells (CD19+) was less in the patient groups than in the control group. There was a positive correlation between the serum levels of beta 2 MG and the degree of activated T cell markers. It is concluded that altered function in T and B cells might be responsible for various immunological abnormalities observed in patients with chronic renal failure on HD or CAPD.

Adult↗