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Results for “immunogenicity”

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PubMed1990

Immunogenicity of rat renal allograft nephron components in vivo. Lack of correlation between MHC expression and immunogenic potential.

Cultured rat nephron components--i.e., tubular cells, glomerular mesangial cells, and glomerular epithelial cells--were compared with cultured rat heart endothelial cells for their in vivo immunogenicity using the primed rejection assay (PRA). Gamma-interferon (gIFN) was used to regulate the class I and class II MHC antigen expression of the cells tested. The heart endothelial cells proved to be the only cell type capable of inducing a maximal rejection response in the native state. This was achieved with a cell number of 10(6) when the survival of a subsequent heart allograft from a relevant donor was reduced from 5 to 3 days. All kidney nephron components proved to be immunogenic in PRA but to a far lesser extent than the endothelial cells. A reduction of graft survival from 5 to 4 days was achieved with a cell number of 10(6) cells, and no immunogenic effect (with the exception of mesangial cells contaminated by a small number of macrophages) was observed in smaller cell numbers. The gIFN-treated endothelial cells were more potent than untreated endothelial cells. They reduced the graft survival to 4 days with a cell number of 10(3) and caused a maximal reduction of the survival to 3 days with a cell number of 10(5). The nephron components failed to increase their immunogenicity after 3-day gIFN treatment, regardless of a high increase in their class I and class II expression rates. The study suggests that, in contrast to the endothelial cells, none of the nephron components are able to act as an antigen-presenting cell on their own.

Animals↗

PubMed1979

Foot-and-mouth disease virus immunogenic capsid protein VPT: N-terminal sequences and immunogenic peptides obtained by CNBr and tryptic cleavages.

The immunogenic capsid protein (VPT), circa 30 kiladaltons (kd), of foot-and-mouth disease virus was examined for (i) its ability to induce neutralizing antibody in guinea pigs after chemical modifications and CNBr or tryptic cleavages and (ii) N-terminal amino sequence homology across three virus types. The immunogenicity of VPT was inactivated by glutaraldehyde treatment, carboxymethylation and maleylation or citraconylation. However, de-citraconylation restored part of the lost activity. Cleavage of type A12 VPT with CNBr produced an immunogenic peptide of circa 13 kd. A slightly larger (ca. 16 kd) immunogenic doublet, VPTab, was obtained by tyrptic cleavage of VPT in the virion. Sequence homologies of circa 85% were found between the first 26 amino acids at the N-terminus of VP chains from virus types A12 strain 119 (A12), C3 Resende (C3R) and O1 Brugge (O1B).

Amino Acid Sequence↗

PubMedDate not supplied

Early macrophage and cytokine response during the growth of immunogenic and non-immunogenic murine tumors.

Very little data exist on the mechanisms of innate immunity during the first days after syngeneic tumor inoculation. Nonspecific macrophage reaction precedes the development of specific immune response and is important for further tumor growth and stroma formation. We investigated two lymphoma cell lines of the same origin, differing in immunogenicity: non-immunogenic parental strain P388 and its highly immunogenic subline P388/adria. Early systemic inflammatory response resulted in the enhancement of nitric oxide (NO) and superoxide production by peritoneal macrophages which was at a maximum on the first day after s.c. tumor inoculation and was observed in mice bearing either of these tumors independently of immunogenicity. It was followed by a transient elevation of the serum levels of pro-inflammatory cytokines: TNF-alpha IL-6. In order to evaluate the role of inflammatory response, vaccinations with lethally irradiated lymphoma cells were performed. After two weekly injections, the mice were challenged s.c. with live tumor cells of the same subline. Effective vaccination with P388/adria lymphoma cells induced retardation of tumor growth in parallel with down-regulation of peritoneal macrophage activity and abrogation of serum cytokine release. Non-effective immunization with P388 cells influenced neither tumor growth nor macrophage functions and cytokine level. Thus, a positive correlation was found between down-regulation of the inflammatory response and inhibition of tumor growth. We suppose that, in efficiently immunized mice, special mechanisms exist which are responsible for down-regulation of the inflammatory reaction. Macrophage products may facilitate tumor cell survival by preventing apoptosis or participate in the activation of tumor neoangiogenesis. Suppression of these activities may serve as an important tool for the inhibition of tumor growth at the early stages of malignant transformation.

Animals↗

PubMed1985

[Immunogenicity of viable tumor cells--comparison of immunogenicity between xenogenized tumor cells and BCG-tumor cell vaccine].

We compared the immunogenicity of FV-KMT-17 (fibrosarcoma, KMT-17 cells which had been xenogenized by infection with Friend leukemia virus (FV] and BCG + KMT-17 (KMT-17 cells which had been admixed with BCG), both of which can be used as viable tumor cell vaccines. The strength of immunogenicity shown by ETD50 (50% effective tumor dose), the number of immunizing cells required for a 50% suppression of growth of 10(7) KMT-17 cells, was 2.1 X 10(3) in FV-KMT-17 and 36.3 X 10(3) in BCG + KMT-17. The LTD50 (50% lethal tumor dose) which was required to kill 50% of rats immunized with 10(5) FV-KMT-17 was more than 10,000 times as high as the amount of LTD50 in normal rats. The LTD50 in rats immunized with the same number of BCG + KMT-17 was only 3,680 times higher than the amount in normal rats. These results indicate that the immunogenicity of FV-KMT-17 is much stronger than that of BCG + KMT-17. The difference in immunogenicity between the two vaccines was also observed in the tumor -neutralizing activities of spleen cells obtained from rats which had been immunized with them, as measured by Winn assay. Moreover, the antitumor activity of spleen cells from rats immunized with FV-KMT-17 concentrated in the carrageenan-non-sensitive and plastic nonadherent cells, while that of spleen cells from rats immunized with BCG + KMT-17 was observed in both carrageenan-sensitive and plastic adherent cells as well as nonadherent cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1983

Drug-induced immunogenic changes of murine leukemia cells: dissociation of onset of resistance and emergence of novel immunogenicity.

n vivo exposure of tumor-bearing mice to the antineoplastic agent 5-(3,3-dimethyl-1-triazenyl)-1H-imidazole-4-carboxamide (DTIC) results in increased immunogenicity of tumor cells, an event often referred to as "chemical xenogenization" (CX). To verify the hypothesis of DTIC-induced somatic mutation(s) as the major mechanism underlying CX, studies were performed to dissociate CX from the onset of drug resistance, which was invoked in the past as an event leading to selection of preexisting immunogenic clones. Therefore, experiments were done with a DTIC-susceptible tumor line treated with DTIC and quinacrine dihydrochloride (Q), an antimutagenic compound, according to selected experimental schedules. At different transplant generations, the CX and the onset of drug resistance were evaluated. The results show that a) Q does not prevent the onset of DTIC resistance, b) DTIC-resistant clones arising after treatment with DTIC plus Q are not immunogenic, and c) CX is selectively antagonized by Q. The present data confirm that DTIC-induced immunogenicity is not the result of a selection mechanism mediated by the drug and give further support to the hypothesis that the molecular mechanism of CX may be related to somatic mutation(s).

Animals↗

PubMed1981

Characterization of immunogenic properties of haptenated liposomal model membranes in mice. V. Effect of membrane composition on humoral and cellular immunogenicity.

This paper describes the effect of altering liposomal membrane composition on humoral and cellular immunogenicity of haptenated liposomes in mice. Antibody formation was determined by enumeration of direct, plaque-forming cells in the spleen and delayed-type hypersensitivity (DH) was measured with a footpad swelling test. Humoral immunogenicity of haptenated liposomes was strongly influenced by membrane phospholipid, cholesterol and charged amphiphile composition. Haptenated liposomes prepared from phospholipids with a low (dioleoyl- and dilauroyl-phosphatidylcholine) or high (distearoyl phosphatidylcholine) phase-transition temperature were less immunogenic than those prepared from phospholipids with an intermediate phase-transition temperature (dipalmitoyl phosphatidylcholine and sphingomyelin). In general, increasing the amount of liposomal membrane cholesterol induced a higher humoral response. These results are discussed in relation to liposomal membrane fluidity. Induction of an optimal DH with haptenated liposomes did not occur in the absence of the adjuvant dimethyl dioctadecyl ammonium bromide (DDA). When DDA was used, alterations in membrane composition did not influence cellular immunogenicity. From these results it was concluded that 'intermediate' liposomal membrane fluidity is the most important requirement for induction of optimal antibody formation with haptenated liposomes and that a certain physicochemical configuration of the antigen, provided by the adjuvant DDA, is a prerequisite for induction of DH.

Adjuvants, Immunologic↗

PubMed1994

Immunogenicity of synthetic HIV-1 gp120 V3-loop peptide-conjugate immunogens.

A successful prophylactic human immunodeficiency virus type 1 (HIV-1) vaccine must elicit an immune response that will prevent establishment of the persistent viral infection. The only response shown to be effective in this regard is virus-neutralizing antibody directed against the viral gp120 hypervariable V3-loop region. Conjugate immunogens, containing cyclic peptides representing the V3 determinant covalently bound to a carrier protein, were capable of eliciting virus-neutralizing antibodies. The consistency of the response was related to peptide size. The smaller cyclic peptides, expressing relatively conserved sequences from the V3-loop apex, were poor inducers of neutralizing activity. In contrast, the largest cyclic peptides mediated neutralizing responses that were similar to those observed and previously reported for intact gp120 immunogens. A cyclic synthetic peptide expressing most of the prototypic HIV-1 MN variant V3 determinant warrants further study as a potentially effective vaccine immunogen.

AIDS Vaccines↗

PubMed1997

Cross-clade immune responses after immunization with a whole-killed gp120-depleted human immunodeficiency virus type-1 immunogen in incomplete Freund's adjuvant (HIV-1 immunogen, REMUNE) in human immunodeficiency virus type-1 seropositive subjects.

Lymphocyte proliferation responses to gp120-depleted HZ321 virus (clade A) antigen were compared to BAL human immunodeficiency virus (HIV) virus antigen (clade B) responses, clade E HIV virus antigen responses, and purified native p24 antigen responses in 15 human immunodeficiency virus type-1 (HIV-1) seropositive subjects immunized with a whole-killed inactivated gp120-depleted HIV-1 antigen in Incomplete Freund's adjuvant (HIV-1 immunogen, REMUNE). A significant increase in lymphocyte proliferation to HZ321 antigen was observed after immunization with the HIV-1 immunogen (p = 0.02). A strong association was demonstrated between the HIV-1 immunizing antigen, HZ321, and native p24 antigen responses (r = 0.80, p < 0.0001). Furthermore, a strong association in terms of proliferative responses was demonstrated between HZ321 virus (clade A) responses and BAL virus (clade B) (r = 0.95, p < 0.0001) and clade E virus antigen (r = 0.92, p < 0.0001). Proliferative responses to HIV antigens also correlated with baseline CD4 counts. Taken together, these results support the specificity of immune responses induced by REMUNE (HIV-1 immunogen). The development of cross-reactive immune responses between clades and to the more conserved epitopes of the virus have implications in the development of therapeutic and prophylactic HIV vaccines.

AIDS Vaccines↗

PubMed2003

[Transgenic potato containing immunogenic gene of avian coronavirus and its immunogenicity in mice].

To check the feasibility of expression of the immunogenic gene of avian coronavirus infectious bronchitis virus (IBV) in plants, the transformation of S1 gene of IBV into potato and the immunogenicity of its expression product was studied. The S1 gene of IBV-ZJ971 strain was inserted into plasmid pBI121 under the control of 35 S promoter. Agrobacterium fumefaciens EHA105 with the recombinant vector pBI121 was obtained by tri-parental mating method. So, an efficient potato transformation system mediated by Agrobacterium fumefaciens was established. The rates of calli and shoots differentiation were 100%, and more than 95% respectively, for transgenic potato with S1 gene of IBV. PCR and Southern blot analyses showed that IBV S1 gene was integrated into genomic DNA of the potato plant and most transgenic plants had two copies of S1 gene of IBV. In our experiments, 47 transgenic plantlets have been obtained. Northern blot and ELISA analyses indicated that most transgenic plants could normally transcribe and translate S1 gene of IBV, though the levels of transcription and translation were different in various transgenic plants. Immunity assay with BALB/C mice showed that expression products of transgenic potato with S1 gene of IBV were immunogenic, and ELISA antibody titer reached 1:20 to 1:40 and 1:80 to 1:160 with doses of 0.5 g and 1 g, respectively. Virus neutralization (VN) antibodies were detected by tracheal organ cultures, and the results showed that VN titers reached respectively 1:160 to 1:320 and 1:320 to 1:2048 with doses of 0.5 g and 1 g.

Animals↗

PubMed1988

[Results of radioiodine treatment of patients with immunogenic and non-immunogenic hyperthyroidism using different focal doses].

The aim of this study was to check the efficacy of radioiodine (131I) therapy (RIT) in a large number of patients (n = 506) suffering from immunogenic or non-immunogenic hyperthyroidism (Graves' disease, Plummer's disease). Since there is no causal cure for immunogenic hyperthyroidism RIT provides, like all other modalities, only a moderate rate of success which is clearly dose-related. Applying 60 Gy, normal thyroid function can be achieved in only 54% of the cases. A dose of 150 Gy succeeds in 86% of the cases. The solitary decompensated autonomous adenoma (DAA) can be eliminated surgically as well as by RIT with a high degree of success (95%). Contrary to surgery, RIT does not have any noticeable early or late morbidity. The high rate of success of RIT in patients with DAA could be confirmed in two groups with different follow-up periods (16 and 65 months). As expected, the rate of hypothyroidism increased from 11% in the early group to 23% in the late group. Multinodular autonomous adenomas can be eliminated successfully using RIT as well. The concept to apply a dose of 400 Gy to the total functional autonomous tissue as determined by ultrasound yields better results (95%) than 150 Gy to the whole thyroid gland as measured by ultrasound (88%). The rate of hypothyroidism as shown by these results (up to a maximum of 62% after RIT of Graves' disease using 150 Gy) is the lesser evil compared to remaining or recurrent hyperthyroidism since these patients can be treated with thyroid hormones without problems.

Adenoma↗

PubMed1987

Density-dependent recognition of cell surface GM3 by a certain anti-melanoma antibody, and GM3 lactone as a possible immunogen: requirements for tumor-associated antigen and immunogen.

A mouse monoclonal antibody M2590, previously established after immunization of mice (C57BL/6) with syngeneic melanoma B16 cells and showing preferential reactivity with various types of melanoma over other tumor and normal cells or tissues, was shown to be directed to GM3 ganglioside. Since GM3 is widely distributed in essentially all types of animal cells, there is a conflict with the concept of a tumor-associated antigen and immunogen. Studies on the reactivity of M2590 antibody with various cells having different GM3 density at their cell surface, including cells treated with sialidase, liposomes, and solid-phase lipid layer containing different GM3 concentrations, have indicated that 1) reactivity of the antibody M2590 depends greatly on the density of GM3 exposed at the cell surface, on liposomes, or on solid phase; and 2) there is a threshold density that is recognized by the antibody in all-or-none fashion. In addition, the antibody M2590 reacts not only with GM3 but also with GM3 lactone, and the binding affinity of the antibody to GM3 lactone is strikingly higher than to GM3; however, the antibody does not react with GM3 ethyl ester. GM3 lactone was detected in melanoma as 3H-labeled GM3 gangliosidol after melanoma cells were directly treated with NaB[3H]4. A comparative immunization of BALB/c mice with GM3 and GM3 lactone showed that GM3 lactone is a much stronger immunogen than GM3, although the antibody elicited reacts with both GM3 and its lactone. Thus, the real immunogen could be GM3 lactone, although it is a minor membrane component.

Animals↗

PubMed1981

[High-immunogenic mutants of Salmonella with two independently of each other attenuating markers as potential vaccines from bacteria capable of multiplication. I. communication: usefulness of the purin-auxotrophy for the isolation of high-immunogenic and stable double-marker strains (author's transl)].

The Salmonella example demonstrates a principle for the isolation of high-immunogenic, stable Salmonella-mutants with two independently of each other attenuating mutations as potential vaccines from bacteria capable of multiplication. The isolation of such double-marker vaccination-strains is verified by the treatment of a single-marker strain (for instance an attenuated high-immunogenic auxotrophic pheno-type) with mutagen and the following selection of clones with the marker purin-auxotrophy as a second attenuating mutation. The demonstrated double-marker strains S. typhimurium his-155 pur-4 and S. dublin met-91 pur-23 are designated by the following parameters: Stability under the conditions of the practical vaccine application; immunogenicity for mice by one immunization only, and separability from homologous wild strains with simple laboratory methods.

Animals↗

PubMed1984

Adoptive immune therapy in mice bearing poorly immunogenic metastases, using T lymphocytes stimulated in vitro against highly immunogenic mutant sublines.

MDW3, a highly immunogenic and non-tumorigenic (tum-) mutant of the poorly immunogenic metastatic murine tumor called MDAY-D2, has been employed in an immune therapy scheme for the treatment of widespread established visceral MDAY-D2 metastases in syngeneic mice. MDW3 was selected from a mutagenized population of MDAY-D2 cells for the ability to grow in the presence of toxic concentrations of wheat-germ agglutinin (WGA) in vitro. The mutant expresses a common tumor-associated antigen (TAA) present on MDAY-D2 as well as a new antigen whose presence enhances the anti-TAA cell-mediated immune response in vivo and in mixed lymphocyte tumor cultures (MLTC) in vitro. For immune therapy, spleen cells from DBA/2 mice which had rejected an inoculum of MDW3 cells were restimulated in MLTC and injected i.v. into MDAY-D2 tumor-bearing mice. Two protocols were used. In the first, mice were given an i.v. injection of 10(3) MDAY-D2 cells ("artificial metastasis") and subsequently treated with 400 R whole-body irradiation and MDW3-stimulated T cells. Such mice had a 75% long-term survival rate, whereas 400 R alone, or no treatment, resulted in 25% and 0% long-term survivors, respectively. In the second protocol, treatment of mice bearing a 12-day-old subcutaneous MDAY-D2 tumor by surgical removal of the solid tumor, 400 R whole-body irradiation, and systemic administration of MDW3-stimulated spleen cells, resulted in a 75-100% survival rate, whereas omitting any part of the treatment resulted in 0-50% survival rates. The treatment increased splenic anti-TAA CTL activity, and the mice acquired immunity against the new antigen on MDW3, suggesting that the injected lymphocytes were proliferating in the host. The optimal combination of resection, whole-body irradiation and passive infusion of MDW3-stimulated spleen cells was ineffective when used on mice bearing a tumor-antigen-loss variant of MDAY-D2, suggesting that success of our immune therapy protocol required specific recognition of the tumor-associated antigen of MDAY-D2.

Animals↗

PubMed2000

IL-12-Dependent enhancement of CTL response to weak class I-restricted peptide immunogens requires coimmunization with T helper cell immunogens.

The effect of in vivo administration of rmIL-12 on the CTL response to immunization with a weakly immunogenic class I-restricted peptide emulsified in incomplete Freund's adjuvant was investigated. In the absence of IL-12, peptide-specific CTL responses were significantly greater following coimmunization with class I-restricted peptide and T helper cell antigens than following immunization with the class I-restricted peptide alone. IL-12-dependent enhancement of the CTL response to peptide immunization was demonstrated in the presence of, but not in the absence of, coimmunization with T helper cell antigen. These findings indicate that IL-12 enhancement of the CTL response to weak class I-restricted immunogens is T helper cell dependent. Treatment with rmIL-12 also enhanced the CTL response to immunization with cDNA encoding both CTL and T helper cell epitopes. These findings are relevant to the design of vaccines containing tumor-associated class I-restricted peptides currently being tested as an immunotherapy for cancer patients.

Animals↗

PubMed1998

Co-expression of immunogenic determinants by the same cellular immunogen is required for the optimum immunotherapeutic benefit in mice with melanoma.

Tumor-associated T cell epitopes are recognized by T cells in the context of determinants specified by class I loci. Since the rejection of foreign histocompatibility antigens is known to enhance tumor immunity, immunization with a cellular vaccine that combined the expression of both syngeneic and allogeneic class I determinants could have important immunological advantages over a vaccine that expressed either syngeneic or allogeneic determinants alone. To investigate this question in a mouse melanoma model system, we tested the immunotherapeutic properties of B16 melanoma x LM fibroblast hybrid cells in C57BL/6J mice with melanoma. Like C57BL/6J mice, B16 cells expressed H-2Kb class I determinants and (antibody-defined) melanoma-associated antigens. LM cells, of C3H mouse origin, formed H-2Kk determinants along with B7.1, a co-stimulatory molecule that can activate T cells. The B16 x LM hybrid cells co-expressed H-2Kb and H-2Kk class I determinants, B7.1 and the melanoma-associated antigens. C57BL/6J mice with melanoma, immunized with the semi-allogeneic hybrid cells, developed CD8-mediated melanoma immunity and survived significantly (P < 0.005) longer than mice with melanoma immunized with a mixture of the parental cell types. The failure of melanoma immunity to develop in mice injected with the mixture of parental cells indicated that co-expression of the immunogenic determinants by the same cellular immunogen was necessary for an optimum immunotherapeutic effect. Augmented immunity to melanoma in mice immunized with the semi-allogeneic hybrid cells points toward an analogous form of therapy for patients with melanoma.

Animals↗

PubMed2002

Immunogenicity of recombinant L7/L12 ribosomal protein of Neisseria meningitidis--high prevalence of specific antibodies in humans but limited immunogenicity for T cells.

The rplL gene, coding for ribosomal protein L7/L12 of Neisseria meningitidis was cloned and expressed as a fusion protein. The recombinant protein was used in Western blots and lymphocyte proliferation assays to study the prevalence of specific antibodies in human sera and the immunogenicity for the cellular immune system. Most of the serum samples studied were found to be positive for L7/L12-specific antibodies. A number of peripheral blood mononuclear cell preparations tested displayed activation in lymphocyte proliferation assays. The magnitude of activation (stimulation index) was moderate, and there was no correlation with a history of meningococcal disease. The high prevalence of specific antibodies is explained by the high carriage rate of meningococci in the normal population or cross-reactivity to ribosomal proteins of other bacteria, thus indicating immunogenicity. However, meningococcal L7/L12 does not seem to be a potential T cell antigen.

Amino Acid Sequence↗

PubMed1990

Synthetic immunogens constructed from T-cell and B-cell stimulating peptides (T:B chimeras): preferential stimulation of unique T- and B-cell specificities is influenced by immunogen configuration.

In our effort to develop synthetic immunogens as vaccines, we have focused on the combination of a known T-cell stimulating peptide with putative B-cell stimulating peptide epitopes derived from the sequences of respiratory syncytial (RS) virus proteins. The T-cell stimulating peptide consists of residues 45 through 60 of the 1A protein of RS virus, and it also contains an overlapping antibody binding (B-cell) site. Herein, we have combined the 1A T-cell stimulating peptide with a putative B-cell peptide epitope derived from the viral G glycoprotein using linear synthesis or using chemical crosslinking. The chimeric immunogens were compared to each other and to free peptides for their T- and B-cell stimulating properties. Both chimeras had potent T-cell stimulating and antibody-inducing activity. However, T-cells primed to free peptide differentially recognized the two chimeras and immunization with the chimeras primed T-cells with different specificity. Most strikingly, the two chimeras had opposite antibody-inducing properties: The chimera constructed by linear synthesis overwhelmingly elicited antibody directed against the G peptide, whereas the chimera constructed by chemical crosslinking overwhelmingly elicited antibody directed against the 1A peptide. Competition blocking studies revealed that the chimeras adopted different configurations in solution. The resulting antibody response, and hence the B-cell clone elicited, was consistent with the antibody accessibility of the individual peptide epitope.

Amino Acid Sequence↗

PubMed1994

Enhanced immunogenicity of protein-dextran conjugates: I. Rapid stimulation of enhanced antibody responses to poorly immunogenic molecules.

In view of our observation that anti-immunoglobulin antibody conjugated to high-molecular-weight dextran stimulates high levels of B-cell activation (Brunswick et al. J. Immunol. 1989, 143, 1239), we coupled T cell-dependent antigens to dextran. When mice were immunized, in the absence of adjuvant, with a BSA-dextran conjugate (BSA-dex), a persistent, high-titre anti-BSA IgG1 response was induced. Titres were dose-dependent and seen with as little as 10 micrograms of conjugated protein. Anti-BSA titres were detected as early as day 7, usually peaked at about day 14 and persisted for at least 4 weeks. Anti-hapten antibodies were also elicited in mice that were immunized with haptenated BSA covalently bound to dextran, and secondary responses could be induced even after inoculation of the unconjugated protein. Covalent attachment of the protein to the polymer was necessary, and the response was specific, as coinjection of BSA-dex and an unrelated antigen, goat IgG, did not elicit detectable anti-goat antibodies. The immunogenic potential of these conjugates did not depend on the ability of the dextran carrier to induce antibody, inasmuch as they stimulated high levels of anti-protein antibody in mice unresponsive to dextran. A minimum size dextran polymer was required for enhanced immunogenicity as conjugates of BSA with dextran of molecular mass 500 or 2000 kDa but not of 70 kDa gave detectable anti-BSA titres.

Adjuvants, Immunologic↗