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At least 757 records · Page 42Linked to original sources
PubMed2005

Fractionated locoregional low-dose radioimmunotherapy improves survival in a mouse model of diffuse-type gastric cancer using a 213Bi-conjugated monoclonal antibody.

PURPOSE: Locoregional radioimmunotherapy of i.p. tumor cell dissemination of diffuse-type gastric cancer using the alpha-emitter 213Bi displayed good therapeutic results after a single application depending on the time interval between tumor cell inoculation and injection of the 213Bi-immunoconjugate. The aim of the present study was to compare single versus double i.p. injection of a tumor-specific antibody (d9MAb) conjugated with low activities of 213Bi in terms of therapeutic efficacy and toxicity. EXPERIMENTAL DESIGN: Nude mice were inoculated i.p. with 1 x 10(7) human gastric cancer cells (HSC45-M2) expressing tumor-specific mutant d9-E-cadherin (d9-E-cad). After tumor cell inoculation, the mice were injected i.p. with a single injection at day 1 or 8, or double injections at days 1 and 8 or days 8 and 15 with 0.37, 0.74, or 1.48 MBq 213Bi-d9MAb. Therapeutic efficacy was determined by median survival, and toxicity was evaluated by leukocyte and platelet counts. The development of i.p. carcinomatosis was monitored by carcinoembryonic antigen concentrations in the serum of the mice. RESULTS: The median survival of treated animals increased, depending on the time interval (days) between tumor cell inoculation and therapy, and the injected activity, from 22 days of untreated mice to 48 days (0.37 MBq, 1 day), 84 days (0.37 MBq, 1 and 8 days), 37 days (0.37 MBq, 8 days), 46 days (0.37 MBq, 8 and 15 days), 42 days (0.74 MBq, 8 days), 78 days (0.74 MBq, 8 and 15 days), and 44 days (1.48 MBq, 8 days). The injected activities did not reduce leukocyte and platelet counts. Carcinoembryonic antigen, which was not detectable in the serum of tumor-free mice, increased after tumor cell inoculation and tumor proliferation and decreased after each therapeutic application of 213Bi-d9MAb. CONCLUSIONS: Double application of only 0.37 MBq of 213Bi-d9MAb at days 1 and 8 after tumor cell inoculation significantly prolonged median survival in nude mice suffering from i.p. tumor cell dissemination compared with a single injection. Even in an advanced stage of the disease, double injection of 0.74 MBq at days 8 and 15 was superior to a single injection of 1.48 MBq at day 8 without any sign of toxicity.

Animals↗
PubMed2004

Gemtuzumab ozogamicin (Mylotarg) in children with refractory or relapsed acute myeloid leukemia.

BACKGROUND: Gemtuzumab ozogamicin (GO) is an immunoconjugate consisting of the CD33 antibody and calicheamicin, a potent cytotoxic agent. Developed for targeted treatment of CD33-positive AML, studies in adults showed its efficacy in relapsed and refractory AML. PATIENTS AND METHOD: We report 12 children with multiple relapsed or refractory AML receiving GO as compassionate use. 11 children had initially been treated according to the AML-BFM 93 or 98 protocol, 1 girl received relapse treatment (liposomal daunorubicin/FLAG) due to secondary AML. After relapse, 10 children received an intensive relapse therapy (AML-BFM 97 or international AML-Relapse Study 2001/01). 2 of them had been transplanted in first or second CR before GO therapy. RESULTS: 5 of 12 children responded to treatment with blast reduction to below 5%, but no child achieved CR after GO. Time until reoccurrence of blasts in almost all children with GO response was 3-8 months. In 5 children stem cell transplantation (SCT) was performed after GO therapy. 4 of them suffered from further progression of AML, 1 boy is in second remission with a follow-up of 8 months. 2 children had severe side effects. An anaphylactic reaction with severe hypotension was managed by catecholamine support and intensive care. In 1 girl, who relapsed after SCT in first remission, a veno-occlusive disease of the liver occurred, but could be treated successfully with defibrotide. CONCLUSION: GO therapy can induce blast reduction in children who have no further conventional treatment options. Frequency and severity of adverse events are limited, and therapy seems to be feasible for children with a sufficient general condition. Controlled studies are necessary to learn more about efficacy and side effects, especially implications for further therapy.

Acute Disease↗
PubMed1997

A covalent fluorescent-gold immunoprobe: simultaneous detection of a pre-mRNA splicing factor by light and electron microscopy.

Immunoprobes that combine a fluorescent label with a 1.4-nm gold cluster compound have been prepared by covalent conjugation with polyclonal antibody Fab' fragments. These new immunoconjugates allow the collection of two complementary sets of data, from fluorescence and electron microscopy, from a single labeling experiment. We find that incorporation of one or more fluorescein moieties into the coordinated ligands of the 1.4-nm Nanogold gold cluster label yields a stable, dual-function immunolabel in which fluorescence quenching is negligible. In a second synthetic strategy, Nanogold and fluorescein were separately covalently conjugated to Fab' fragments to yield a probe with very similar properties. With the use of Fab' fragments, the entire probe is smaller than a whole IgG molecule, and it exhibited excellent penetration properties. It was used to localize the pre-mRNA splicing factor SC35 in the HeLa cell nucleus by both fluorescence and electron microscopy.

Fluorescein↗
PubMed1987

An immunoenzyme triple-staining method using both polyclonal and monoclonal antibodies from the same species. Application of combined direct, indirect, and avidin-biotin complex (ABC) technique.

For immunohistological analysis, simultaneous detection of multiple cellular epitopes, as compared to single staining of serial sections, is sometimes needed. Therefore, immunoenzyme triple-staining protocols were tested with polyclonal and monoclonal antibodies on tissue sections and cytospin preparations. Various immunoconjugates were used in different combinations of methods, of which not all proved to be suitable. Of the tested protocols, one yielded superior results for both monoclonal and polyclonal antibodies, with optimal preservation of their original avidity. The method consists of a combination of indirect, direct, and avidin-biotin complex technique. The three antigens can be distinguished clearly and selectively by the reaction products of the enzyme activities of beta-galactosidase (green), alkaline phosphatase (blue), and horseradish peroxidase (red).

Alkaline Phosphatase↗
PubMed1992

A 1.4-nm gold cluster covalently attached to antibodies improves immunolabeling.

A large gold cluster (Au1.4nm) was covalently coupled to IgG and Fab' fragments. Its gold core is 1.4 nm in diameter and the Fab'-Au1.4nm immunoconjugate is the smallest gold immunoprobe that can be seen directly in the conventional electron microscope. It is useful in high-resolution immunolabeling, providing a resolution of 7.0 nm. The cluster's visibility can be enhanced with silver development for use in EM or light microscopy for histological purposes, or to detect less than or equal to 0.2 pg of antigen in immunoblots. By using a gold compound with covalent attachment, a number of advantages over colloidal gold probes are realized, including better resolution, stability, uniformity, sensitivity, and complete absence of aggregation; its small size should also improve penetration and more quantitative labeling of antigenic sites.

Animals↗
PubMed2005

New strategies for the treatment of acute myeloid leukemia including antibodies and other novel agents.

The prognosis for younger adults (< or = 55-60 years) with acute myeloid leukemia (AML) has improved during the last four decades. However, there has been little progress in the treatment of older adults. This disappointing observation is important because the median age of patients with AML is about 70 years. Approximately 60%-80% of younger adults with AML achieve complete remission (CR) with the cytotoxic agents cytarabine and an anthracycline such as daunorubicin or idarubicin or the anthracenedione mitoxantrone. However, only 30%-40% of such patients are alive and disease-free at 5 years. Among older adults, CR is achieved in 40%-55%, but there are very few long-term survivors. Many studies have evaluated the impact of alternative doses and schedules, as well as additional cytotoxic drugs, on the prognosis for this group of patients. The outcome has not improved substantially beyond that achieved with conventional doses of an anthracycline and cytarabine followed by high-dose cytarabine consolidation.Several factors identified at diagnosis can predict outcome. The most important of these is the karyotype of the leukemic cells. Another critical factor is the presence of transmembrane transporter proteins, which confer multidrug resistance and mutations in or overexpression of specific genes such as WT1, C/EBPalpha, BAX, and BCL-2/BAX ratio, BAALC, EVI1, KIT and FLT3. The development of specific agents directed at gene mutations, signal transduction pathways and unique cell surface antigens provide the foundation for new therapeutic strategies. Such agents include the immunoconjugate gemtuzumab ozogamicin, multidrug resistance inhibitors, farnesyltransferase inhibitors, histone deacetylase and proteosome inhibitors, antiangiogenesis agents, FLT3 inhibitors, apoptosis inhibitors, and nucleoside analogs. All of these agents can potentially address the heterogeneous abnormalities in AML and significantly improve the outcome for patients.

Adult↗
PubMed2003

Multidrug resistance protein attenuates gemtuzumab ozogamicin-induced cytotoxicity in acute myeloid leukemia cells.

Gemtuzumab ozogamicin (GO) is a novel immunoconjugate therapy for acute myeloid leukemia (AML). P-glycoprotein (Pgp) confers resistance to GO and is associated with a worse clinical response. To address whether multidrug resistance protein (MRP) affects GO susceptibility, we characterized Pgp, MRP1, and MRP2 expression in CD33+ cell lines and CD33+ AML samples and analyzed the effect of the Pgp inhibitor cyclosporine (CSA) and the MRP inhibitor MK-571 on GO-induced cytotoxicity. MRP1, but not MRP2, expression correlated with MRP activity. MK-571 enhanced GO-induced cytotoxicity in Pgp-negative/MRP-positive NB4 and HL-60 cells. CSA, but not MK-571 alone, restored GO susceptibility in Pgp-positive/MRP-positive TF1 cells; however, MK-571 enhanced cytotoxicity in the presence of CSA. All patient samples exhibited MRP activity, and 17 of 23 exhibited Pgp activity. CSA increased GO-induced cytotoxicity in 12 Pgp-positive samples, whereas MK-571 alone was effective in only one sample with minimal Pgp activity. In 3 Pgp-positive/MRP-positive samples, MK-571 enhanced GO-induced cytotoxicity in the presence of CSA. Thus, MRP1 may attenuate susceptibility to GO. This effect was comparatively less than that for Pgp and required the inhibition of Pgp for detection in cells that coexpressed both transporters. Because MK-571 and CSA failed to affect cytotoxicity in a portion of Pgp-positive/MRP-positive AML samples, additional resistance mechanisms are likely important.

ATP Binding Cassette Transporter, Subfamily B↗
PubMed2004

Influence of CD33 expression levels and ITIM-dependent internalization on gemtuzumab ozogamicin-induced cytotoxicity.

Gemtuzumab ozogamicin (GO; Mylotarg), a novel immunoconjugate used for treatment of acute myeloid leukemia (AML), contains the humanized anti-CD33 antibody (hP67.6) as a carrier to facilitate cellular uptake of the toxic calicheamicin-gamma(1) derivative. By use of lentivirus-mediated gene transfer to manipulate CD33 expression in myeloid cell lines that normally lack CD33 (murine 32D cells) or have very low levels of CD33 (human OCI-AML3 and KG-1a cells), we here show a quantitative relationship between CD33 expression and GO-induced cytotoxicity. The CD33 cytoplasmic immunoreceptor tyrosine-based inhibitory motifs (ITIMs) control internalization of antibody bound to CD33. Disruption of the ITIMs by introduction of point mutations not only prevented effective internalization of antibody-bound CD33 but also significantly reduced GO-induced cytotoxicity. Together, our data imply a pivotal role of both the number of CD33 molecules expressed on the cell surface and the amount of internalization of CD33 following antibody binding for GO-induced cytotoxicity and suggest novel therapeutic approaches for improvement of clinical outcome of patients treated with GO.

Aminoglycosides↗
PubMed2005

Drug therapy for acute myeloid leukemia.

Although improvement in outcomes has occurred in younger adults with acute myeloid leukemia (AML) during the past 4 decades, progress in older adults has been much less conspicuous, if at all. Approximately 50% to 75% of adults with AML achieve complete remission (CR) with cytarabine and an anthracycline such as daunorubicin or idarubicin or the anthracenedione mitoxantrone. However, only approximately 20% to 30% of the patients enjoy long-term disease survival. Various postremission strategies have been explored to eliminate minimal residual disease. The optimal dose, schedule, and number of cycles of postremission chemotherapy for most patients are not known. A variety of prognostic factors can predict outcome and include the karyotype of the leukemic cells and the presence of transmembrane transporter proteins, which extrude certain chemotherapy agents from the cell and confer multidrug resistance and mutations in or over expressions of specific genes such as WT1, CEBPA, BAX and the ratio of BCL2 to BAX, BAALC, EVI1, KIT, and FLT3. Most recently, insights into the molecular pathogenesis of AML have led to the development of more specific targeted agents and have ushered in an exciting new era of antileukemia therapy. Such agents include the immunoconjugate gemtuzumab ozogamicin, multidrug resistance inhibitors, farnesyl transferase inhibitors, histone deacetylase and proteosome inhibitors, antiangiogenesis agents, Fms-like tyrosine kinase 3 (FLT3) inhibitors, and apoptosis inhibitors.

Acute Disease↗
PubMed2001

Multidrug-resistance phenotype and clinical responses to gemtuzumab ozogamicin.

Expression of multidrug resistance (MDR) features by acute myeloid leukemia (AML) cells predicts a poor response to many treatments. The MDR phenotype often correlates with expression of P-glycoprotein (Pgp), and Pgp antagonists such as cyclosporine (CSA) have been used as chemosensitizing agents in AML. Gemtuzumab ozogamicin, an immunoconjugate of an anti-CD33 antibody linked to calicheamicin, is effective monotherapy for CD33(+) relapsed AML. However, the contribution of Pgp to gemtuzumab ozogamicin resistance is poorly defined. In this study, blast cell samples from relapsed AML patients eligible for gemtuzumab ozogamicin clinical trials were assayed for Pgp surface expression and Pgp function using a dye efflux assay. In most cases, surface expression of Pgp correlated with Pgp function, as indicated by elevated dye efflux that was inhibited by CSA. Among samples from patients who either failed to clear marrow blasts or failed to achieve remission, 72% or 52%, respectively, exhibited CSA-sensitive dye efflux compared with 29% (P =.003) or 24% (P <.001) among samples from responders. In vitro gemtuzumab ozogamicin--induced apoptosis was also evaluated using an annexin V--based assay. Low levels of drug-induced apoptosis were associated with CSA-sensitive dye efflux, whereas higher levels correlated strongly with achievement of remission and marrow blast clearance. In vitro drug-induced apoptosis could be increased by CSA in 14 (29%) of 49 samples exhibiting low apoptosis in the absence of CSA. Together, these findings indicate that Pgp plays a role in clinical resistance to gemtuzumab ozogamicin and suggest that treatment trials combining gemtuzumab ozogamicin with MDR reversal agents are warranted. (Blood. 2001;98:988-994)

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2003

A novel endocytic pathway induced by clustering endothelial ICAM-1 or PECAM-1.

Antibody conjugates directed against intercellular adhesion molecule (ICAM-1) or platelet-endothelial cell adhesion molecule (PECAM-1) have formed the basis for drug delivery vehicles that are specifically recognized and internalized by endothelial cells. There is increasing evidence that ICAM-1 and PECAM-1 may also play a role in cell scavenger functions and pathogen entry. To define the mechanisms that regulate ICAM-1 and PECAM-1 internalization, we examined the uptake of anti-PECAM-1 and anti-ICAM-1 conjugates by endothelial cells. We found that the conjugates must be multimeric, because monomeric anti-ICAM-1 and anti-PECAM-1 are not internalized. Newly internalized anti-ICAM-1 and anti-PECAM-1 conjugates did not colocalize with either clathrin or caveolin, and immunoconjugate internalization was not reduced by inhibitors of clathrin-mediated or caveolar endocytosis, suggesting that this is a novel endocytic pathway. Amiloride and protein kinase C (PKC) inhibitors, agents known to inhibit macropinocytosis, reduced the internalization of clustered ICAM-1 and PECAM-1. However, expression of dominant-negative dynamin-2 constructs inhibited uptake of clustered ICAM-1. Binding of anti-ICAM-1 conjugates stimulated the formation of actin stress fibers by human umbilical vein endothelial cells (HUVEC). Latrunculin, radicicol and Y27632 also inhibited internalization of clustered ICAM-1, suggesting that actin rearrangements requiring Src kinase and Rho kinase (ROCK) were required for internalization. Interestingly, these kinases are part of the signal transduction pathways that are activated when circulating leukocytes engage endothelial cell adhesion molecules, suggesting the possibility that CAM-mediated endocytosis is regulated using comparable signaling pathways.

Amides↗
PubMed2002

Tumor suppressive monoclonal antibody belonging to the V(H) 7183 family directed to the oncodevelopmental carbohydrate antigen on human hepatocellular carcinoma.

Hep27 monoclonal antibody (Hep27 Mab) was raised by immunizing BALB/c mice with cells of the Thai human hepatocellular carcinoma (HCC) cell line HCC-S102 using hybridoma technology. The Hep27 Mab recognizes oncofetal development antigens by reacting with many HCC, other cancers, fetal and newborn liver but not adult liver. The Hep27 Mab alone markedly inhibits the growth of hepatocellular carcinoma cell lines (65% viability on the third day), suggesting its clinical usefulness. Moreover, complementary DNA (cDNA) for active variable regions of both heavy and light chains of the antibody has been cloned. Sequence analysis of the variable region of the Hep27 Mab revealed that the V(H) and V(L) genes belong to the V(H) 7183 and V(K) families, respectively. We have also characterized the reactivity of the Hep27 Mab to synthetic carbohydrate epitopes and 1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP)-treated HCC-S102 cells. The results showed that the Hep27 Mab recognizes a neoglycolipid containing a mucin core unit and PDMP treatment reduced Hep27 Mab binding activity to HCC-S102 cells, indicating that the Hep27 Mab recognizes a glycolipid antigen on HCC-S102 cells. This Mab may be potentially useful for studying antigenic expression in hepatocellular carcinoma and as a targeting agent for radioimmunodetection and immunoconjugated therapy.

Journal Article↗
PubMed2005

[Radioimmunotherapy for treatment of acute myeloid leukaemia and myelodysplastic syndrome: conceptual chances].

The prognosis of patients with acute myeloid leukaemia (AML) has improved considerably by introduction of aggressive consolidation chemotherapy and haematopoietic stem cell transplantation (SCT). Nevertheless, only 20-30% of patients with AML achieve long-term disease-free survival after SCT. The most common cause of treatment failure is relapse. Additionally, mortality rates are significantly increased by therapy-related causes such as toxicity of chemotherapy and complications of SCT. Including radioimmunotherapies in the treatment of AML and myelodyplastic syndrome (MDS) allows for the achievement of a pronounced antileukaemic effect for the reduction of relapse rates on the one hand. On the other hand, no increase of acute toxicity and later complications should be induced. These effects are important for the primary reduction of tumour cells as well as for the myeloablative conditioning before SCT. This paper provides a systematic and critical review of the currently used radionuclides and immunoconjugates for the treatment of AML and MDS and summarizes the literature on primary tumour cell reductive radioimmunotherapies on the one hand and conditioning radioimmunotherapies before SCT on the other hand.

Humans↗
PubMed2005

Chronicles in drug discovery.

New brief reports this month include: Strategies for Duchenne Muscular Dystrophy: Various approaches are being explored to abate the dystrophic process including cellular therapies (transplanting stem cells or myogenic precursors into muscles), molecular approaches (delivering a functional or correcting the mutant dystrophin gene), such as MyoDys, Biostrophin(R) and antisense technology, and pharmacotherapeutics, which include calcium channel blockers, calpain inhibitors, phosphodiesterase inhibitors and monoclonal antibodies; Immunotherapy for Multiple Myeloma: Increasing numbers of antibodies and immunoconjugates with anticancer drugs are entering clinical development; Acute respiratory distress syndrome is among the most frequent reasons for intensive care. Current medications include antibiotics, diuretics, drugs to counteract low blood pressure caused by shock, anxiolytics and antiinflammatories, while there are eight potential drugs in active development; Pulmonary Hypertension: Drugs intervening at four signaling pathways (endothelin, prostacyclin, nitric oxide and platelet-derived growth factor), which are implicated in pulmonary hypertension, include readily available bosentan, sildenafil citrate and sitaxsentan sodium and investigational aviptadil and TBC-3711, among others.

Animals↗
PubMed2002

Overcoming multidrug resistance in taxane chemotherapy.

Paclitaxel (Taxol) and docetaxel (Taxotère) are currently two of the most important anticancer drugs in cancer chemotherapy. However, clinical treatment with these taxane agents often encounters undesirable side effects and multidrug resistance (MDR) caused by overexpression of P-glycoprotein (Pgp). Photoaffinity labeling of Pgp using photoreactive radiolabeled paclitaxel analogs along with molecular modeling has revealed a unique binding region for paclitaxel on the C-terminal half of Pgp. Highly efficient taxane-based MDR reversal agents (TRAs) have been developed. Extensive structure-activity relationship (SAR) studies have led to the development of new generation taxanes that possess 2-3 orders of magnitude higher potencies against human cancer cell lines expressing the MDR phenotype. One of these taxanes, SB-T-1 10131 (IDN5109, BAY59-8862), exhibits excellent activity against a variety of drug-sensitive and drug-resistant cancer cell lines as well as human tumor xenografts in mice. This taxane is orally active with excellent bioavailability, and is currently undergoing phase II human clinical trials. Novel taxane-antibody immunoconjugates have shown very promising results for tumor-specific delivery and release of an extremely cytotoxic taxane, wherein epidermal growth factor receptor is used as the specific antigen on the tumor surface of human squamous cancer xenograft in SCID mice.

ATP Binding Cassette Transporter, Subfamily B↗
PubMed1997

The development of antibody delivery systems to target cancer with highly potent maytansinoids.

Improving the tumour selectivity of cytotoxic drugs through conjugation to tumour-reactive monoclonal antibodies may lead to novel, more potent agents for cancer therapy. The maytansinoid drugs are 100- to 1000-fold more cytotoxic in vitro than current clinical anticancer drugs. We recently demonstrated that conjugation of maytansinoid drugs to monoclonal antibodies renders them highly efficacious against cancers of breast and colon in both in vitro and in in vivo tumour models. Antibody-maytansinoids represent a new generation of immunoconjugates that may yet fulfil the promise of effective cancer therapy through antibody targeting of cytotoxic agents.

Journal Article↗
PubMed2001

Efficacy and safety of gemtuzumab ozogamicin in patients with CD33-positive acute myeloid leukaemia in first relapse.

Gemtuzumab ozogamicin (CMA-676, Mylotarg, an antibody-targeted chemotherapy agent, was recently approved by the FDA for the treatment of patients with CD33+ acute myeloid leukaemia (AML) in first relapse who are 60 years of age or older and who are not considered candidates for other types of cytotoxic chemotherapy. In combined Phase II studies of 142 patients with CD33+ AML in first relapse, gemtuzumab ozogamicin monotherapy was associated with a 30% overall response rate. While treated patients had relatively high incidences of myelosuppression, grade 3 or grade 4 hyperbilirubinaemia (23%) and elevated hepatic transaminases (17%), the incidences of grade 3 or grade 4 mucositis (4%) and infections (28%) were low compared with what might be expected in association with conventional chemotherapeutic treatment. In contrast with the usual in-patient administration of cytarabine and anthracycline-containing induction regimens, a large number of patients were treated with gemtuzumab ozogamicin as outpatients (38% and 41% for the first and second doses, respectively). Two prognostic factors for patients with AML in first relapse, age and duration of complete remission, had relatively little effect on response rates to gemtuzumab ozogamicin. Preliminary data in pediatric patients also suggest the immunoconjugate to be reasonably well tolerated. Studies of gemtuzumab ozogamicin in combination with anthracycline and cytarabine are underway. Gemtuzumab ozogamicin, administered to patients with CD33+ AML in first relapse, has shown overall response rates comparable to conventional agents and a safety profile that appears to be favourable.

Acute Disease↗
PubMed2002

Monoclonal antibody therapy of haematological malignancies.

Over the past decade the potential for delivering targeted therapy against malignant disease by the use of monoclonal antibodies (MAbs) has begun to be realised. Haematological malignancies, because of the relative accessibility of the malignant cell in blood and bone marrow and the understanding of haemopoietic lineage-specific antigens, have provided a successful testing ground for this therapy. There have been many technical developments which have allowed the safe delivery of more potent antibody constructs. The development of human or chimeric antibodies has largely overcome the problems associated with host immune responses to rodent-derived MAbs. Protein engineering to combine MAbs with other biologically active molecules such as radioisotopes, toxins, chemotherapy and cytokines, has made available a new range of agents with clinical activity. The purpose of this review is not to give a catalogue of all therapeutic antibodies but rather to outline the principles of this approach, the current state of knowledge, and possible directions for future development. First, the general requirements and strategies for use of both unmodified and conjugated MAbs are discussed, followed by a summary of the trial data in specific lymphoid and myeloid haemopoietic malignancies. The focus is on MAbs that now have an accepted use in clinical practice, with some discussion of newer MAbs under development. Vaccination strategies and the role of MAbs in bone marrow transplantation are not discussed in detail. The trials of the next decade will address issues such as: whether clinical activity translates into improved survival; the optimal strategies and timing for clinical use; whether increasing potency of MAbs (as in radio- and immunoconjugates) will increase toxicity and, finally, what other potential molecules, such as those influencing cell growth and death, may be targeted.

Animals↗