SEARCH · PubMed Health

Results for “BALB/c mouse model”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources

PubMed1990

The pathogenesis of Leishmania aethiopica infection in BALB/c mice.

A mouse model for L. aethiopica infection is described. BALB/c mice were unable to clear an infection with 1 x 10(7) promastigotes injected into the hind footpad. However, there was no ulceration of the lesion and no development of overt clinical symptoms after 203 days of infection. Spread of viable organisms was evident in the draining lymph node but not in the spleen or liver. The control of the infection was associated with the development of classical delayed hypersensitivity responses to phenolized promastigotes and appeared as a localized granulomtaous infiltration. The infiltration had features of classical tuberculoid granulomas, but superimposed on it was a strong eosinophilic infiltration. The relevance of such cells though unclear is discussed.

Animals↗

PubMed1998

Plasticity of CD44s expression during progression and metastasis of fibrosarcoma in an animal model system.

CD44s (standard isoform), which binds hyaluronan (HA), has been analyzed for its significance during fibrosarcoma progression and metastasis in an athymic nude mouse model using Balb/c 3T3 cells transformed with ras or sis oncogenes. While ras (but not sis) transformation leads to upregulated expression of mouse CD44s and HA binding, transfection/overexpression of human CD44s gene (hCD44s) elicited remarkable plasticity of expression during progression and metastasis. In 3T3, hCD44s induced tumorigenesis, HA binding, and micrometastatic competence to lungs and other organs. In tumorigenic (but nonmetastatic) sis transformants or ras-deleted revertants, it also induced micrometastatic competence. Conversely, large primary tumors and overt metastases lost hCD44s expression and HA binding via hypermethylation of hCD44s gene. Tail vein injections revealed that hCD44s greatly increased the efficiency of colonization of the lung microvasculature at the earliest stages. These studies indicate that hCD44s overexpression and possibly its HA binding are critical for conveying metastatic competence but are antagonistic or selected against during aggressive primary tumor or overt metastasis outgrowth. This remarkable plasticity of expression and its consequences offer an ideal system for dissecting the molecular mechanisms operating during fibrosarcoma progression and metastasis.

Animals↗

PubMed1994

Pharmacokinetics of pretargeted monoclonal antibody 2D12.5 and 88Y-Janus-2-(p-nitrobenzyl)-1,4,7,10-tetraazacyclododecanetetraacetic acid (DOTA) in BALB/c mice with KHJJ mouse adenocarcinoma: a model for 90Y radioimmunotherapy.

Three-step pretargeting for radioimmunotherapy in BALB/c mice with KHJJ tumors was done with monoclonal antibody (mAb) 2D12.5, which is specific for yttrium-1,4,7,10-tetraazacyclododecanetetraacetic acid (DOTA) but nonspecific for the tumor. Tumor uptake was by passive diffusion of mAb through leaky neovasculature in the tumor. The three steps were: (a) anti-hapten mAb 2D12.5 (0 h); (b) polyvalent haptenprotein conjugate chase (20 h); and (c) 88Y-labeled monovalent DOTA or bivalent Janus-DOTA haptens (21 h) and organ and tumor bioassay (24 h). Rapid tumor (T) uptake and high tumor:blood ratio (T:BL) was seen 3 h after injection after step c. For monovalent 88Y-DOTA, T = 1.7%/g* and T:BL = 16:1; for bivalent 88Y-Janus-DOTA, T = 4.41%/g* and T:BL = 21:1 at 3 h (*, P < 0.001). Blood and bone plus marrow were << 1%/g, and liver was < 1%/g. The 24-h whole body retention was approximately 5% of injected dose with 1% in tumor (20% of total), 1.8% in other organs, and 2.2% in carcass; the 24-h whole body retention of covalent nonspecific antibody conjugates was > 80% of injected dose. The biological half-life in the tumor of 0.9 microCi 88Y-Janus-DOTA was approximately 24 h, measured daily for 5 days. Activity in microCi/g of tumor and blood for 90Y equimolar to the amount of 88Y injected (0.9 microCi 88Y = 0.744 pmol = 36.47 microCi 90Y) was used for calculating the area under the curve of tumor and blood in microCi-h/g of 90Y. The 90Y radiation absorbed dose (RAD) from multiplying microCi-h/g x the 90Y absorbed dose constant, 1.99 RAD-g/microCi-h, gave T = 89 RAD and BL = 3.7 RAD. The therapeutic ratio from RAD T:RAD BL = 24:1. These results indicate that pretargeting 90Y hapten-specific mAb for radioimmunotherapy has considerable promise.

Acetates↗

PubMed2006

Alpha-internexin as a corneal autoantigen in spontaneous autoimmune keratitis mouse model.

PURPOSE: The purpose of this study was to identify target antigens of autoimmune keratitis with a disease-prone mouse model. METHODS: BALB/c nude mice grafted with embryonic rat thymi (TG nude mice) develop various organ-localized autoimmune lesions, including keratitis. A hybridoma producing a monoclonal antibody (OT-20), specific for corneal epithelium was established by using spleen cells from this model mouse of keratitis, and the target of OT-20 was identified by immunoblot analysis. Then, using the antigen, T-cell proliferation and cytokine production by TG nude mice with keratitis were examined. RESULTS: Immunoblot analysis revealed alpha-internexin to be the target antigen of OT-20 that specifically recognizes corneal epithelium. Sera from TG nude mice with keratitis reacted with alpha-internexin on Western blot analysis, and the T cells of these mice on stimulation with alpha-internexin exhibited proliferation responses and produced IL-2, IFN-gamma, and TNF-alpha, but not IL-4 or IL-5. CONCLUSIONS: These results suggest that alpha-internexin is one of the corneal antigens associated with keratitis, developing spontaneously in TG-nude mice, with a probable pathogenic role.

Animals↗

PubMed1998

Redefining peripheral tolerance in the BALB/c to CBA mouse cardiac allograft model: vascular and cytokine analysis after transient CD4 T cell depletion.

BACKGROUND: To evaluate cardiac allografts from recipients that had achieved peripheral tolerance after transient CD4+ T cell depletion, we analyzed cellular infiltrate, cytokine expression, and vascular thickening. Long-surviving cardiac allografts from tolerant recipients were compared with acutely rejecting allografts and isografts. METHODS AND RESULTS: In CBA mice treated with anti-CD4 (GK1.5, 0.5 mg intraperitoneally on days 1-28), BALB/c cardiac allografts survived >100 days. These recipients were tested for tolerance at >70 days, by challenge with donor and third-party (C57BL/6) skin grafts. BALB/c skin grafts survived >30 days, although C57BL/6 skin was rejected in <12 days, reflecting alloantigen-specific peripheral tolerance. When vascular thickening in graft arteries was assessed and computerized measurements performed, heart allografts from tolerant recipients showed significantly increased percentage of luminal occlusion compared with isografts (47% compared with 1.2%). Semiquantitative reverse transcriptase-polymerase chain reaction was used to assess normalized intragraft mRNA transcripts for cytokines and T cell markers, with immunoperoxidase staining of frozen sections to confirmed the presence of protein. Compared with rejecting grafts, well-preserved hearts from tolerant mice had lower levels of macrophage and T cell infiltration and decreased transcription of interferon-gamma, interleukin (IL)-2, IL-10, and inducible nitric oxide synthase. IL-4 expression was similar in both groups. CONCLUSIONS: The degree of tolerance achieved allowed specific acceptance of donor skin grafts, preserved primary graft function, and reduced inflammatory activation. Tolerance did not, however, completely prevent macrophage and T cell infiltration of the graft or the development of vascular lesions typical of chronic rejection.

Animals↗

PubMed1999

Oligodeoxynucleotides containing CpG motifs modulate the allergic TH2 response of BALB/c mice to Bet v 1, the major birch pollen allergen.

BACKGROUND: The use of adequate adjuvants to modulate the allergic T(H2)-type immune response is a promising concept for future immunotherapy of type I allergy. Bacterial DNA or oligodeoxynucleotides containing CpG motifs (CpG-ODNs) have been demonstrated to foster T(H1)-type immune responses. OBJECTIVE: We investigated the adjuvanticity of CpG-ODNs and their capability to modulate the allergic T(H2) response in a mouse model. METHODS: BALB/c mice were treated with CpG-ODNs and Bet v 1, the major birch pollen allergen, in different experimental setups. Allergen-specific antibody responses, T(H) cytokines, and eosinophilic infiltration of the airways were investigated. RESULTS: Intraperitoneal administration of Bet v 1 together with aluminium hydroxide led to a typical T(H2) response. In contrast, coadminstration of CpG-ODNs with Bet v 1 in aluminium hydroxide resulted in markedly increased T(H1) activities (high IgG2a levels) and subsequently to reduced airway inflammation. The T(H1)-like immune response indicated by these humoral findings was also reflected by decreased IL-5 and increased IFN-gamma levels in cell cultures. CpG-ODNs as sole adjuvants with Bet v 1 did not lead to measureable Ig responses after subcutaneous or intraperitoneal immunizations; after intranasal application, 3 of 10 mice reacted. Nevertheless, a prophylactic effect was obtained with all routes tested; that is, mice treated subsequently with an established aerosol sensitization protocol displayed altered immune responses characterized by drastically elevated levels of Bet v 1-specific IgG2a, indicating a T(H1)/T(H0)-like immunity. Application of CpG-ODNs after aerosol sensitization also induced IgG2a. CONCLUSION: By inducing T(H1)/T(H0)-biased immune responses to allergens, the use of CpG-ODNs as adjuvants may have important impacts for new forms of specific immunotherapy in type I hypersensitivity.

Adjuvants, Immunologic↗

PubMed2005

An anti-inflammatory role for a phosphoinositide 3-kinase inhibitor LY294002 in a mouse asthma model.

Phosphoinositide 3-kinase (PI3K) exhibits broad functional effects in immune cells. We investigated the role of PI3K in allergic airway inflammation using LY294002, a specific PI3K inhibitor, in a mouse asthma model. BALB/c mice were sensitized and challenged with ovalbumin (OVA), and developed airway eosinophilia, mucus hypersecretion, elevation in cytokine levels, and airway hyperresponsiveness. Intratracheal administration of LY294002 significantly inhibited OVA-induced increases in total cell counts, eosinophil counts, and IL-5, IL-13, and eotaxin levels in bronchoalveolar lavage fluid. Histological studies show that LY294002 dramatically inhibited OVA-induced lung tissue eosinophilia and airway mucus production. In addition, LY294002 significantly suppressed OVA-induced airway hyperresponsiveness to inhaled methacholine. Western blot analysis of whole lung lysates shows that LY294002 markedly attenuated OVA-induced serine phosphorylation of Akt, a direct downstream substrate of PI3K. Taken together, our findings suggest that inhibition of PI3K signaling pathway can suppress T-helper type 2 (Th2) cytokine production, eosinophil infiltration, mucus production, and airway hyperresponsiveness in a mouse asthma model and may have therapeutic potential for the treatment of allergic airway inflammation.

Animals↗

PubMed2005

Systemic delivery of liposomal short-chain ceramide limits solid tumor growth in murine models of breast adenocarcinoma.

In vitro tumor cell culture models have illuminated the potential therapeutic utility of elevating the intracellular concentration of the antimitogenic and proapoptotic sphingolipid, ceramide. However, although cell-permeable, short-chain ceramide is an effective apoptotic agent in vitro, its use as an in vivo, systemically delivered therapeutic is limited by its inherent lipid hydrophobicity and physicochemical properties. Here, we report that the systemic i.v. delivery of C6-ceramide (C6) in a pegylated liposomal formulation significantly limited the growth of solid tumors in a syngeneic BALB/c mouse tumor model of breast adenocarcinoma. Over a 3-week treatment period, a well-tolerated dose of 36 mg/kg liposomal-C6 elicited a >6-fold reduction in tumor size compared with empty ghost liposomes. Histologic analyses of solid tumors from liposomal-C6-treated mice showed a marked increase in the presence of apoptotic cells, with a coincident decrease in cellular proliferation and in the development of a microvessel network. Liposomal-C6 accumulated within caveolae and mitochondria, suggesting putative mechanisms by which ceramide induces selective cancer cell cytotoxicity. A pharmacokinetic analysis of systemic liposomal-C6 delivery showed that the pegylated liposomal formulation follows first-order kinetics in the blood and achieves a steady-state concentration in tumor tissue. Confirming the therapeutic utility of i.v. liposomal-C6 administration, we also shown diminution of solid tumor growth in a human xenograft model of breast cancer. Together, these results indicate that bioactive ceramide analogues can be incorporated into pegylated liposomal vehicles for improved solubility, drug delivery, and antineoplastic efficacy.

Adenocarcinoma↗

PubMed2006

Enhanced efficacy of 90Y-radiolabeled anti-Lewis Y humanized monoclonal antibody hu3S193 and paclitaxel combined-modality radioimmunotherapy in a breast cancer model.

UNLABELLED: Radioimmunotherapy (RIT) of solid tumor is often limited in efficacy because of restrictions in achieved tumor dose. In an effort to overcome this, the combination of RIT with other therapeutic modalities was investigated in an animal model of breast carcinoma. The rationale for this combined-modality RIT (CMRIT) was to increase the therapeutic efficacy of RIT through the use of paclitaxel to arrest cells in the radiosensitive G(2)/M phase of the cell cycle. METHODS: In this study, the biodistribution and therapeutic efficacy of (90)Y-radiolabeled humanized anti-Lewis Y hu3S193 monoclonal antibody ((90)Y-hu3S193) RIT in combination with paclitaxel chemotherapy was explored in a Lewis Y-expressing MCF-7 tumor xenografted BALB/c nude mouse model of breast cancer. RESULTS: Biodistribution studies demonstrated excellent tumor targeting and limited normal tissue uptake by (90)Y-hu3S193. A therapeutic study with established tumors assessed (90)Y-hu3S193 as a single agent and demonstrated significant antitumor effects in all animals receiving a single intravenous 1.85 or 3.70 MBq dose of this treatment compared with phosphate-buffered saline placebo controls (P = 0.0008 vs. P < 0.0001). Complete responses were observed in all animals in the 3.70 MBq study arm for the duration of the study. Single-dose (90)Y-hu3S193 plus paclitaxel (600 microg) CMRIT displayed improved efficacy over single-modality therapies, with a significant difference (P < 0.0001) between the mean percentage change in tumor volume in mice receiving 0.46 MBq (90)Y-hu3S193 alone and when combined with 600 mug paclitaxel. CONCLUSION: The significant efficacy of (90)Y-hu3S193 and paclitaxel CMRIT at low radiation doses in this model of breast carcinoma indicates its therapeutic potential and warrants further investigation into this promising therapeutic approach.

Animals↗

PubMed2026

Nonclinical investigation of the potential of MHAA4549A, an anti-influenza A therapeutic antibody, to mediate antibody-dependent enhancement.

Antibody-dependent enhancement (ADE) of infection and disease is a theoretical safety risk for antiviral antibodies against seasonal viruses with antigenic drift, such as influenza. ADE of infection may occur if virus-specific antibodies at subtherapeutic, nonneutralizing concentrations facilitate virus uptake, thus potentially enhancing virus replication. In contrast, ADE of disease reflects exacerbation of viral disease severity through viral replication-dependent or -independent mechanisms. Because of the theoretical concern of ADE, nonclinical safety assessment of therapeutic anti-influenza antibodies includes a thorough evaluation of ADE potential. The current set of studies was conducted to investigate the potential of MHAA4549A-a broadly specific, neutralizing, therapeutic anti-influenza A antibody-to elicit ADE of infection and disease of influenza H3N2 A/Aichi/2/68 (X31) across a broad dose range. Assessment of ADE was based on totality of results from both in vitro and mouse influenza studies with integration across study endpoints. In vitro studies demonstrated that MHAA4549A can mediate increased X31 entry into human and murine monocytic cells, but increased uptake did not result in enhanced viral replication or release under physiologic conditions. In a mouse model of X31 infection, intravenous administration of MHAA4549A resulted in delayed body weight recovery, but no exacerbation in orthogonal endpoints including mortality, lung viral titers or genomes, lung weights, or severity of influenza pneumonia. Overall, the totality of nonclinical data did not demonstrate any clear indication of ADE of infection at nonneutralizing concentrations, suggesting a low risk for MHAA4549A to cause enhanced influenza A-mediated disease at subtherapeutic doses.

Animals↗

PubMed2005

Detection of Neospora caninum in the semen and blood of naturally infected bulls.

A prospective study was designed to investigate the presence of Neospora caninum in semen and blood of eight bulls seropositive to N. caninum using nested-PCR procedures. Positive semen and blood samples were bioassayed in a BALB/c nu/nu mouse model. Specific anti-N. caninum serological and interferon-gamma (IFN-gamma) responses were also studied. In parallel, five seronegative bulls acted as non-infected controls. All bulls were located in a collaborating AI centre and monitored for 22 weeks. Six of eight seropositive bulls showed N. caninum DNA in their semen and/or blood samples at some time during the course of the study. In all positive semen samples, we consistently found Neospora-DNA in the cell fraction and not in seminal plasma. Parasite load, as determined by a real-time PCR in nested-PCR positive semen samples, ranged from 1 to 10 parasites/ml. We found no association between the presence of N. caninum DNA in semen and blood. N. caninum could not be detected in the BALB/c nu/nu mice inoculated with PCR-positive semen or blood samples. Specific IgG antibody levels in seropositive bulls fluctuated over time, at times falling below cut-off level. The response was predominantly IgG2, with significant differences compared to control bulls (P < 0.05). The overall mean specific IFN-gamma response in seropositive bulls was also higher than those observed in the control group (P < 0.05), although extensive variation in individual responses was observed among bulls and over time. No significant association was found between bulls showing Neospora DNA in semen, blood, or both, and specific IgG, IgG1, IgG2, IgM and IgA levels or IFN-gamma response. This study is the first to report the presence of Neospora DNA in semen and blood of naturally-infected bulls. Our observations indicate intermittent presence of N. caninum in blood and semen and shedding in semen in low numbers.

Animals↗

PubMed1998

A peptide domain on gingipain R which confers immunity against Porphyromonas gingivalis infection in mice.

The cysteine proteinases referred to as gingipains R (gingipain R1 and gingipain R2) and gingipain K produced by Porphyromonas gingivalis are virulence factors of this periodontal pathogen which likely act by interrupting host defense mechanisms and by participating in the penetration and destruction of host connective tissue. To examine the effect of immunization with gingipains R on the ability of P. gingivalis to colonize and invade in the mouse chamber model, BALB/c mice were immunized intraperitoneally with the 95-kDa gingipain R1, the 50-kDa gingipain R2, or multiple antigenic peptide (MAP)-conjugated gingipain R-derived peptides and then challenged with P. gingivalis. Immunization of mice with the 95-kDa gingipain R1, the 50-kDa gingipain R2, or a peptide derived from the N-terminal sequence of the catalytic domain of gingipains R (peptide A) followed by challenge with P. gingivalis A7436 resulted in protection from P. gingivalis invasion. In contrast, immunization with peptides corresponding to either a sequence encompassing the catalytic cysteine residue of gingipains R (peptide B) or an identical sequence within the catalytic domains of gingipain R1 and gingipain K (peptide C), followed by challenge with P. gingivalis, did not protect animals, nor did immunization with a peptide corresponding to sequences within the adhesion/hemagglutinin domain of gingipain R1 (peptide D) which have been shown to be directly involved in the hemagglutinin activity of gingipain R1. However, the immunoglobulin G (IgG) titer obtained following immunization with peptide D was comparable to that obtained following immunization with the N-terminal peptide (peptide A). Competitive enzyme-linked immunosorbent assays, using either the 95-kDa gingipain R1 or gingipain K as the competing soluble antigen, indicated that 42 and 53% of the antibodies induced by immunization with heat-killed bacteria recognize gingipain R1 and gingipain K, respectively; however, even at very high concentrations, the 50-kDa gingipain R2 did not hinder IgG binding to P. gingivalis. These results indicate that antibodies directed to the amino-terminal region of the catalytic domain of gingipains R are capable of inducing a protective immune response against P. gingivalis infection in the mouse chamber model.

Adhesins, Bacterial↗

PubMed1997

Vitamin D3 analog, EB1089, inhibits growth of subcutaneous xenografts of the human colon cancer cell line, LoVo, in a nude mouse model.

PURPOSE: In this study, we investigated the effect of the vitamin D3 analog, EB1089, on the growth of subcutaneous xenografts of the human colon cancer cell line, LoVo, in a nude mouse model. METHODS: BALB/c Nu/Nu nude mice were inoculated subcutaneously with 10(6) LoVo cells. EB1089 dissolved in isopropanol was administered intraperitoneally and orally on alternate days at doses of 0.1, 0.5, and 2.5 microg/kg/day. Control animals received isopropanol alone. Tumor volumes estimated using the formula 0.5 X length X (width)2. The tumor kinetic index was determined by immunohistochemical detection of proliferating cell nuclear antigen. RESULTS: Significant dose-dependent inhibition of tumor growth was seen. After 20 days of treatment with 0.1 microg/kg/day EB1089, mean tumor volume in treated mice was 41 to 49 percent less than that in control animals (P < 0.01). Significant inhibition of tumor growth was also seen with 0.5 microg/kg/day EB1089 after 22 days of treatment (51 percent of control P < 0.01). Treatment with 2.5 microg/kg/day resulted in weight loss that required termination of this group; these mice were subsequently found to be hypercalcemic. The tumor kinetic index was significantly lower in tumors treated with 0.1 microg/kg/day EB1089 compared with that for control tumors (8 vs. 30 percent in controls). CONCLUSION: These findings suggest that the vitamin D3 analog, EB1089, is a potent antiproliferative agent for some human colon cancers.

Animals↗

PubMed2005

Ganoderma tsugae supplementation alleviates bronchoalveolar inflammation in an airway sensitization and challenge mouse model.

Ganoderma tsugae (a Chinese mushroom Songshan lingzhi) cultivated in Taiwan is extensively used in Chinese traditional medicine to treat different diseases. To determine whether G. tsugae has anti-inflammatory effects on bronchoalveolar inflammation in vivo, we investigated the anti-inflammatory effects of G. tsugae products, YK01 and YK07, on bronchoalveolar inflammation using an airway sensitization and challenge mouse model. Female BALB/c mice were weekly sensitized by intraperitoneal injection of ovalbumin (OVA) three times and challenged with aerosolized OVA twice. Differential cell counts of infiltrating leukocytes, inflammatory mediators, cytokines in bronchoalvelor lavage fluid (BALF) of OVA-challenged mice were examined after continuously consuming G. tsugae diets for 5 weeks. We found that supplementation of G. tsugae significantly decreased total infiltrating leukocytes and lymphocyte percentage in BALF in the experimental groups. Supplementation of G. tsugae also significantly reduced inflammatory mediators in BALF including histamine, prostaglandin E2, eotaxin, and protein levels, however the levels of pro-inflammatory cytokines, interleukin (IL)-1beta and IL-6, in BALF did not significantly change. These results suggest that both G. tsugae supplementation diets YK01 and YK07 might alleviate bronchoalveolar inflammation via decreasing the infiltration of inflammatory cells and the secretion of inflammatory mediators into the local tissues of lungs and airways. Further, these results indicate that the relief of bronchoalveolar inflammation in an airway sensitization murine model provides a possible therapeutic application for G. tsugae in allergic asthma.

Alveolitis, Extrinsic Allergic↗

PubMed1997

Protein aggregates seem to play a key role among the parameters influencing the antigenicity of interferon alpha (IFN-alpha) in normal and transgenic mice.

PURPOSE: During long-term treatment of various malignant or viral diseases with IFN-alpha up to 20% of patients develop anti-IFN-alpha antibodies for as yet unknown reasons. METHODS: To address this issue, a mouse model using Balb/C mice was established and the relevance of several potentially anti-IFN-alpha antibodies inducing factors was studied. RESULTS: The model revealed that both a higher frequency of injections and a higher dosage of IFN-alpha were more immunogenic and that the route of administration affected the antibody response to IFN-alpha. The intrinsic immunostimulatory activity of IFN-alpha itself also enhanced the immune response. IFN-alpha protein aggregates (IFN-alpha-IFN-alpha and human serum albumin (HSA)-IFN-alpha aggregates), which were recently identified in all marketed IFN-alpha products, were significantly more immunogenic than IFN-alpha monomers. These aggregates broke the tolerance against human IFN-alpha monomers in human IFN-alpha transgenic mice. CONCLUSIONS: Based on these animal studies it is proposed that the immune response to IFN-alpha in humans is most probably elicited by a combination of several factors among which IFN-alpha protein aggregates seem to play a key role.

Adjuvants, Immunologic↗

PubMed1996

Immunoscintigraphy of small-cell lung cancer xenografts with anti neural cell adhesion molecule monoclonal antibody, 123C3: improvement of tumour uptake by internalisation.

The efficacy of three murine monoclonal antibodies (MAbs) for immunoscintigraphy of small-cell lung cancer (SCLS) xenografts was studied in a Balb/c nu/nu mouse model. These Mabs, 123C3, 123A8 and MOC191, belong to cluster 1 of anti-SCLC MAbs and bind to the neural cell adhesion molecule (NCAM) with similar affinity. After intraperitoneal injection of these MAbs, labelled with 125I, the highest uptake in tumour tissue was obtained with MAb 123C3. Seven days after the administration of this MAb 13.9% of the injected dose per gram of tumour tissue was retained in the tumour. The corresponding tumour tissue ratios ranged from 3.97 for blood to 31.03 for colon. The imaging results and the tumour uptake were less favourable for the two other MAbs, 123A8 and MOC191 (fractions of injected dose respectively 6.7% and 9.2%), although affinity, biological activity after labelling and uptake in non-tumour tissues were very similar for all three MAbs. These results may be explained by the differences in the interaction between the MAbs and the tumour cells. Mab 123C3 is internalised into tumour cells, whereas both other anti-NCAM Mabs are not. Internalisation into NCI H69 cells was demonstrated in vitro by radioimmunoassay, confocal laser scanning microscopy and electron microscopy. The internalised fraction of MAb 123C3 was 22.3% after 24h, whereas this fraction was only 7.5% for MAb 123A8. Although the internalised radiolabeled Mabs are usually degraded and dehalogenated intracellularly, the retained radioactivity is high. Apparently, intracellular degradation of radiolabelled MAb 123C3 and subsequent secretion of radioactive iodine did not prevent the accumulation of intracellular radioactivity. In conclusion, accumulation and retention of radioactivity in the tumour tissue, due to internalisation of radiolabelled MAbs, may improve the results immunoscintigraphy.

Animals↗

PubMed2002

Endotoxins prevent murine IgE production, T(H)2 immune responses, and development of airway eosinophilia but not airway hyperreactivity.

BACKGROUND: Contact with immunomodulatory factors, such as LPS, in early infancy is associated with decreased allergen sensitization. OBJECTIVE: We sought to study the effects of systemic or airway exposure with LPS on the development of allergen sensitization, eosinophilic airway inflammation, and increased in vivo airway reactivity (AR) in a mouse model. METHODS: BALB/c mice were systemically sensitized with ovalbumin (OVA) plus adjuvant on days 1 and 14 and challenged through the airways with allergen on days 34 to 36. We performed measurement of OVA-specific IgE serum levels, in vitro T(H)2 cytokine production, differential cell counts in bronchoalveolar lavage fluids, and assessment of in vivo AR to inhaled methacholine by means of barometric whole-body plethysmography. RESULTS: Systemic LPS administration before OVA sensitization reduced OVA-specific IgE serum levels (426 +/- 76 vs 880 +/- 104 U/mL, P <.01), T(H)2 cytokine production by splenic mononuclear cells (IL-4: 0.08 +/- 0.01 vs 0.17 +/- 0.01 ng/mL; IL-5: 1.98 +/- 0.52 vs 4.11 +/- 0.54 ng/mL; P <.01), and extent of airway eosinophilia (total cell counts: 93 vs 376 x 10(3)/mL; eosinophils: 23% vs 51%; P <.01) compared with that in OVA-sensitized mice. Local LPS administration to sensitized mice before airway allergen challenges particularly induced IFN-gamma production by peribronchial lymph node cells in vitro (1718 +/- 315 vs 483 +/- 103 ng/mL, P <.01) associated with reduced airway eosinophilia compared with that seen in OVA-sensitized mice. Development of increased AR was not affected by systemic or local LPS exposure. Inhibitory effects of LPS on allergen sensitization and eosinophilic airway inflammation were inhibited by administration of anti-IL-12 antibodies before LPS exposure. CONCLUSION: These data indicate that local and systemic application of LPS modulates systemic and local T(H)1/T(H)2 immune responses in a distinct but similarly IL-12-dependent mode.

Allergens↗

PubMed2004

Respiratory syncytial virus induces pneumonia, cytokine response, airway obstruction, and chronic inflammatory infiltrates associated with long-term airway hyperresponsiveness in mice.

BACKGROUND: Respiratory syncytial virus (RSV) infection is associated with acute morbidity (e.g., pneumonia and airway obstruction [AO]) and long-term complications (e.g., airway hyperresponsiveness [AHR]). We present a comprehensive evaluation of the acute and chronic phases of RSV respiratory tract infection, using a mouse model. METHODS: BALB/c mice were inoculated with RSV and monitored for 154 days. RSV loads and cytokines were measured in bronchoalveolar lavage (BAL) samples. Pneumonia severity was assessed using a standard histopathologic score, and pulmonary function was determined by plethysmography. RESULTS: RSV-infected mice exhibited viral replication that peaked on day 4-5 and became undetectable by day 7. These mice developed acute pneumonia (peak days, 4-5) and chronic pulmonary inflammatory infiltrates that lasted up to 154 days after inoculation. BAL concentrations of tumor necrosis factor- alpha, interleukin (IL)-6, interferon- gamma, IL-4, IL-10, KC (an IL-8 homologue), MIG (CXCL9), RANTES, macrophage inflammatory protein-1 alpha, and eotaxin were significantly higher in RSV-infected mice than in control mice. RSV-infected mice developed acute AO during the first week of infection that persisted for 42 days. RSV-infected mice also showed significant AHR in response to methacholine up to 154 days. CONCLUSION: This model provides a means to investigate the immunopathogenesis of RSV infection and its association with reactive airway disease.

Airway Obstruction↗