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In early 2020, the COVID-19 pandemic sparked a global crisis that continues to pose a serious threat to human health and the economy. Further advancement in research is necessary and requires the availability of quality molecular tools, including monoclonal antibodies. Here, we present the development and characterization of a collection of over 40 new monoclonal antibodies directed against different SARS-CoV-2 proteins. Recombinant SARS-CoV-2 proteins were expressed, purified, and used as immunogens. Upon development of specific hybridomas, the obtained monoclonal antibody (mAb) clones were tested for binding to recombinant proteins and infected cells. We generated mAbs against structural proteins, the Spike and Nucleocapsid protein, several non-structural proteins (nsp1, nsp7, nsp8, nsp9, nsp10, nsp16) and accessory factors (ORF3a, ORF9b) applicable in flow cytometry, immunofluorescence, or Western blot. Our collection of mAbs provides a set of novel, highly specific tools that will allow a comprehensive analysis of the viral proteome, which will allow further understanding of SARS-CoV-2 pathogenesis and the design of therapeutic strategies.

Omicron was designated by the WHO as a VOC on 26 November 2021, only 4 days after its sequence was first submitted. However, the impact of Omicron on current antibodies and vaccines remains unknown and evaluations are still a few weeks away. We analysed the mutations in the Omicron variant against epitopes. In our database, 132 epitopes of the 120 antibodies are classified into five groups, namely NTD, RBD-1, RBD-2, RBD-3, and RBD-4. The Omicron mutations impact all epitopes in NTD, RBD-1, RBD-2, and RBD-3, with no antibody epitopes spared by these mutations. Only four out of 120 antibodies may confer full resistance to mutations in the Omicron spike, since all antibodies in these three groups contain one or more epitopes that are affected by these mutations. Of all antibodies under EUA, the neutralisation potential of Etesevimab, Bamlanivimab, Casirivimab, Imdevima, Cilgavimab, Tixagevimab, Sotrovimab, and Regdanvimab might be dampened to varying degrees. Our analysis suggests the impact of Omicron on current therapeutic antibodies by the Omicron spike mutations may also apply to current COVID-19 vaccines.

Vibrio cholerae causes the severe diarrheal disease cholera. Clinical disease and current oral cholera vaccines generate antibody responses associated with protection. Immunity is thought to be largely mediated by lipopolysaccharide (LPS)-specific antibodies, primarily targeting the O-antigen. However, the properties and protective mechanism of functionally relevant antibodies have not been well defined. We previously reported on the early B cell response to cholera in a cohort of Bangladeshi patients, from which we characterized a panel of human monoclonal antibodies (MAbs) isolated from acutely induced plasmablasts. All antibodies in that previous study were expressed in an IgG1 backbone irrespective of their original isotype. To clearly determine the impact of affinity, immunoglobulin isotype and subclass on the functional properties of these MAbs, we re-engineered a subset of low- and high-affinity antibodies in different isotype and subclass immunoglobulin backbones and characterized the impact of these changes on binding, vibriocidal, agglutination, and motility inhibition activity. While the high-affinity antibodies bound similarly to O-antigen, irrespective of isotype, the low-affinity antibodies displayed significant avidity differences. Interestingly, despite exhibiting lower binding properties, variants derived from the low-affinity MAbs had comparable agglutination and motility inhibition properties to the potently binding antibodies, suggesting that how the MAb binds to the O-antigen may be critical to function. In addition, not only pentameric IgM and dimeric IgA, but also monomeric IgA, was remarkably more potent than their IgG counterparts at inhibiting motility. Finally, analyzing highly purified F(ab) versions of these antibodies, we show that LPS cross-linking is essential for motility inhibition. IMPORTANCE Immunity to the severe diarrheal disease cholera is largely mediated by lipopolysaccharide (LPS)-specific antibodies. However, the properties and protective mechanisms of functionally relevant antibodies have not been well defined. Here, we have engineered low and high-affinity LPS-specific antibodies in different immunoglobulin backbones in order to assess the impact of affinity, immunoglobulin isotype, and subclass on binding, vibriocidal, agglutination, and motility inhibition functional properties. Importantly, we found that affinity did not directly dictate functional potency since variants derived from the low-affinity MAbs had comparable agglutination and motility inhibition properties to the potently binding antibodies. This suggests that how the antibody binds sterically may be critical to function. In addition, not only pentameric IgM and dimeric IgA, but also monomeric IgA, was remarkably more potent than their IgG counterparts at inhibiting motility. Finally, analyzing highly purified F(ab) versions of these antibodies, we show that LPS cross-linking is essential for motility inhibition., (Copyright © 2021 Kauffman et al.)

SARS-CoV-2 infection results in viral burden in the respiratory tract, enabling transmission and leading to substantial lung pathology. The 1212C2 fully human monoclonal antibody was derived from an IgM memory B cell of a COVID-19 patient, has high affinity for the Spike protein receptor binding domain, neutralizes SARS-CoV-2, and exhibits in vivo prophylactic and therapeutic activity in hamsters when delivered intraperitoneally, reducing upper and lower respiratory viral burden and lung pathology. Inhalation of nebulized 1212C2 at levels as low as 0.6 mg/kg, corresponding to 0.03 mg/kg lung-deposited dose, reduced the viral burden below the detection limit and mitigated lung pathology. The therapeutic efficacy of an exceedingly low dose of inhaled 1212C2 supports the rationale for local lung delivery for dose-sparing benefits, as compared to the conventional parenteral route of administration. These results suggest that the clinical development of 1212C2 formulated and delivered via inhalation for the treatment of SARS-CoV-2 infection should be considered., Competing Interests: M.S.P., J.-G.P., A.D., F.S.O., M.B., S.S., N.B.E., P.A.G., M.R.W., L.M.-S., and J.J.K. are co-inventors on a patent that includes claims related to the hmAbs described. A.L., J.W., P.L., D.S., and V.L.T. are employees of Aridis Pharmaceuticals., (© 2021 The Author(s).)

Monoclonal antibodies (MAbs) have the potential to assist in the battle against multidrug-resistant bacteria such as carbapenem-resistant Klebsiella pneumoniae (CR- Kp ). However, the characteristics by which these antibodies (Abs) function, such as the role of antibody subclass, must be determined before such modalities can be carried from the bench to the bedside. We performed a subclass switch on anticapsular monoclonal murine IgG 3 (mIgG 3 ) hybridomas and identified and purified a murine IgG 1 (mIgG 1 ) hybridoma line through sib selection. We then compared the ability of the mIgG 1 and mIgG 3 antibodies to control CR- Kp sequence type 258 (ST258) infection both in vitro and in vivo We found by enzyme-limited immunosorbent assay (ELISA) and flow cytometry that mIgG 3 has superior binding to the CR- Kp capsular polysaccharide (CPS) and superior agglutinating ability compared to mIgG 1 The mIgG 3 also, predictably, had better complement-mediated serum bactericidal activity than the mIgG 1 and also promoted neutrophil-mediated killing at concentrations lower than that of the mIgG 1 In contrast, the mIgG 1 had marginally better activity in improving macrophage-mediated phagocytosis. Comparing their activities in a pulmonary infection model with wild-type as well as neutropenic mice, both antibodies reduced organ burden in a nonlethal challenge, regardless of neutrophil status, with mIgG 1 having the highest overall burden reduction in both scenarios. However, at a lethal inoculum, both antibodies showed reduced efficacy in neutropenic mice, with mIgG 3 retaining the most activity. These findings suggest the viability of monoclonal Ab adjunctive therapy in neutropenic patients that cannot mount their own immune response, while also providing some insight into the relative contributions of immune mediators in CR- Kp protection. IMPORTANCE Carbapenem-resistant Klebsiella pneumoniae is an urgent public health threat that causes life-threatening infections in immunocompromised hosts. Its resistance to nearly all antibiotics necessitates novel strategies to treat it, including the use of monoclonal antibodies. Monoclonal antibodies are emerging as important adjuncts to traditional pharmaceuticals, and studying how they protect against specific bacteria such as Klebsiella pneumoniae is crucial to their development as effective therapies. Antibody subclass is often overlooked but is a major factor in how an antibody interacts with other mediators of immunity. This paper is the first to examine how the subclass of anticapsular monoclonal antibodies can affect efficacy against CR- Kp Additionally, this work sheds light on the viability of monoclonal antibody therapy in neutropenic patients, who are most vulnerable to CR- Kp infection.

Most of the current FDA and EMA approved therapeutic monoclonal antibodies (mAbs) are based on humanized or human IgG1, 2, or 4 subclasses and engineered variants. On the structural side, these subclasses are characterized by specific interchain disulfide bridge connections. Different analytical techniques have been reported to assess intact IgGs subclasses, with recently special interest in native ion mobility (IM) and collision induced unfolding (CIU) mass spectrometry (MS). However, these two techniques exhibit significant limitations to differentiate mAb subclasses at the intact level. In the present work, we aimed at developing a unique IM-MS-based approach for the characterization of mAb subclasses at the middle level. Upon IdeS-digestion, the unfolding patterns of the F(ab') 2 and Fc domains were simultaneously analyzed in a single run to provide deeper structural insights of the mAb scaffold. The unfolding patterns associated with the F(ab') 2 domains are completely different in terms of unfolding energies and number of transitions. Thereby, F(ab') 2 regions are the diagnostic domain to provide specific unfolding signatures to differentiate IgG subclasses and provide more confident subclass categorization than CIU on intact mAbs. In addition, the potential of middle-level CIU was evaluated through the characterization of eculizumab, a hybrid therapeutic IgG2/4 mAb. The unfolding signatures of both domains were allowed to corroborate, within a single run, the hybrid nature of eculizumab as well as specific subclass domain assignments to the F(ab') 2 and Fc regions. Altogether, our results confirm the suitability of middle-level CIU of F(ab') 2 domains for subclass categorization of canonical and more complex new generation engineered antibodies and related products.

Activated protein C (APC) is a plasma serine protease with antithrombotic and cytoprotective functions. Based on the hypothesis that specific inhibition of APC's anticoagulant but not its cytoprotective activity can be beneficial for hemophilia therapy, 2 types of inhibitory monoclonal antibodies (mAbs) are tested: A type I active-site binding mAb and a type II mAb binding to an exosite on APC (required for anticoagulant activity) as shown by X-ray crystallography. Both mAbs increase thrombin generation and promote plasma clotting. Type I blocks all APC activities, whereas type II preserves APC's cytoprotective function. In normal monkeys, type I causes many adverse effects including animal death. In contrast, type II is well-tolerated in normal monkeys and shows both acute and prophylactic dose-dependent efficacy in hemophilic monkeys. Our data show that the type II mAb can specifically inhibit APC's anticoagulant function without compromising its cytoprotective function and offers superior therapeutic opportunities for hemophilia.

Cripto-1 is a protein expressed during embryonal development and has been linked to several malignant processes in cancer. Since the discovery of cripto-1 in the late 1980s, it has become a subject of biomarker investigation in several types of cancer which in many cases relies on immunolocalization of cripto-1 using antibodies. Investigating cripto-1 expression and localization in primary glioblastoma cells, we discovered nonspecific binding of cripto-1 antibody to the extracellular matrix Geltrex. A panel of four cripto-1 antibodies was investigated with respect to their binding to the Geltrex matrix and to the cripto-1 positive control cells NTERA2. The cripto-1 expression was varied for the different antibodies with respect to cellular localization and fixation methods. To further elaborate on these findings, we present a systematic review of cripto-1 antibodies found in the literature and highlight some possible cross reactants with data on sequence alignments and structural comparison of EGF domains., (© 2019 Wiley Periodicals, Inc.)

The names and therapeutic indications of monoclonal antibodies must comply with current regulations, which does not prevent the development of commercial strategies around trade names. Some of these practices are based on territorial or legal considerations while others are motivated by real medical concerns. Finally, some of these have a significant financial impact on the community., (© 2019 médecine/sciences – Inserm.)

The number of therapeutic antibodies available in rheumatology increases every year, mainly indicated in chronic inflammatory rheumatisms and other immune-mediated inflammatory diseases. The choice between all these monoclonal antibodies depends on their specificities, patients and diseases characteristics. Until now, there is no reliable biomarker, predictive of response for specialized medicine purpose. Today, therapeutic drug monitoring and anti-drug antibodies testing can help to better adapt the dose of the drug and to help in the decision to switch to another biological drug according to the activity of the inflammatory disease., (© 2019 médecine/sciences – Inserm.)

Antibodies are a key resource in biomedical research yet there are no community-accepted standards to rigorously characterize their quality. Here we develop a procedure to validate pre-existing antibodies. Human cell lines with high expression of a target, determined through a proteomics database, are modified with CRISPR/Cas9 to knockout (KO) the corresponding gene. Commercial antibodies against the target are purchased and tested by immunoblot comparing parental and KO. Validated antibodies are used to definitively identify the most highly expressing cell lines, new KOs are generated if needed, and the lines are screened by immunoprecipitation and immunofluorescence. Selected antibodies are used for more intensive procedures such as immunohistochemistry. The pipeline is easy to implement and scalable. Application to the major ALS disease gene C9ORF72 identified high-quality antibodies revealing C9ORF72 localization to phagosomes/lysosomes. Antibodies that do not recognize C9ORF72 have been used in highly cited papers, raising concern over previously reported C9ORF72 properties., Competing Interests: CL, PM, RK, JS, MK, CC, ZY, FB, OG, HM, TD, AE, LH, JR, PM No competing interests declared, (© 2019, Laflamme et al.)

Elicitation of VRC01-class broadly neutralizing antibodies (bnAbs) is an appealing approach for a preventative HIV-1 vaccine. Despite extensive investigations, strategies to induce VRC01-class bnAbs and overcome the barrier posed by the envelope N276 glycan have not been successful. Here, we inferred a high-probability unmutated common ancestor (UCA) of the VRC01 lineage and reconstructed the stages of lineage maturation. Env immunogens designed on reverted VRC01-class bnAbs bound to VRC01 UCA with affinity sufficient to activate naive B cells. Early mutations defined maturation pathways toward limited or broad neutralization, suggesting that focusing the immune response is likely required to steer B cell maturation toward the development of neutralization breadth. Finally, VRC01 lineage bnAbs with long CDR H3s overcame the HIV-1 N276 glycan barrier without shortening their CDR L1, revealing a solution for broad neutralization in which the heavy chain, not CDR L1, is the determinant to accommodate the N276 glycan., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Monoclonal antibodies (mABs) have been indicated as an innovative technology for the treatment of some types of cancer, since they are capable of targeting and selectively killing tumor cells. However, the high costs of these therapies raise questions as to the sustainability of access. This study aimed to identify the principal characteristics of monoclonal antibodies used in cancer treatment with active marketing authorization in Brazil as of 2016. This was a descriptive retrospective analysis based on consultation of the Brazilian Health Regulatory Agency (Anvisa) website, in which these mABs were characterized according to the target antigen, type of antibody, year of registration, therapeutic indications, and applicant. A total of 14 antibodies were identified with action on seven different target antigens. The most frequent clinical indications were for lymphomas, leukemias, breast cancer, and colorectal cancer. As for type, the study identified three chimeric, six humanized, and five human antibodies. Roche was the applicant in 6 of the 14 mABs, or 43% of the marketing authorization. It was possible to discuss the idea of me-too medicines in the biological market and the idea of a differentiated oligopoly, as well as to think about the tensions in this kind of market. It is expected that the development of new products, although to act on the same biological target, represent the possibility of a competitive increase and, as a result, a decrease in prices practiced by companies. However, this becomes a problem when it is the same pharmaceutical industry that launches on the market new antibodies directed to the same target, with no relevant changes.

In therapeutic monoclonal antibody (mAb) development, charge heterogeneity of a mAb molecule is often associated with critical quality attributes and is therefore monitored throughout development and during QC release to ensure product and process consistency. Elucidating the cause of each charge variant species is an involved process that often requires offline fractionation by ion exchange chromatography (IEX) followed by mass spectrometry (MS) analysis, largely due to the incompatibility of conventional IEX buffers for direct MS detection. In this study, we have developed a method that combines a generic strong cation exchange (SCX) chromatography step with ultrasensitive online native MS analysis (SCX-MS) optimized for mAb separation and detection. As demonstrated by analyzing mAb molecules with a wide range of pI (isoelectric point) values, the developed method can consistently achieve both high-resolution IEX separation and ultrasensitive MS detection of low-abundance charge variant species. Using this method, we analyzed the charge heterogeneity of NISTmAb reference material 8671 (NISTmAb) at both whole antibody and subdomain levels. In particular, due to the high sensitivity, a nonconsensus Fab glycosylation site, present at a very low level (<0.1%), was directly detected in the NISTmAb sample without any enrichment. The structure and location of this Fab glycosylation was further characterized by peptide mapping analysis. Despite the extensive characterization of NISTmAb material in previous studies, this is the first time that this Fab-glycosylated variant has been identified in the NISTmAb, demonstrating the value of this new method in achieving a more comprehensive characterization of charge heterogeneity for therapeutic mAbs.

Objective: To evaluate the potential effects of proprotein convertase subtilisin/kexin type 9 monoclonal antibody (PCSK9-mAb) on high-sensitivity C reactive protein (hs-CRP) concentrations., Design: A systematic review and meta-analysis of randomised controlled trials., Data Sources: PubMed, MEDLINE, the Cochrane Library databases, ClinicalTrials.gov and recent conferences were searched from inception to May 2018., Eligibility Criteria for Selecting Studies: All randomised controlled trials that reported changes of hs-CRP were included., Results: Ten studies involving 4198 participants were identified. PCSK9-mAbs showed a slight efficacy in reducing hs-CRP (-0.04 mg/L, 95% CI: -0.17 to 0.01) which was not statistically different. The results did not altered when subgroup analyses were performed including PCSK9-mAb types (alirocumab: 0.12 mg/L, 95% CI: -0.18 to 0.43; evolocumab: 0.00 mg/L, 95% CI: -0.07 to 0.07; LY3015014: -0.48 mg/L, 95% CI: -1.28 to 0.32; RG7652: 0.35 mg/L, 95% CI: -0.26 to 0.96), treatment duration (≤12w: 0.00 mg/L, 95% CI: -0.07 to 0.07; >12w: -0.11 mg/L, 95% CI: -0.45 to -0.23), participant characteristics (familial hypercholesterolaemia: 0.00 mg/L, 95% CI: -0.07 to 0.07; non-familial hypercholesterolaemia: 0.07 mg/L, 95% CI: -0.12 to 0.26; mix: -0.48 mg/L, 95% CI: -1.28 to 0.32) and treatment methods (monotherapy: 0.00 mg/L, -0.08 to 0.07; combination therapy: -0.08 mg/L, -0.37 to 0.21). Meta-regression analyses suggested no significant linear correlation between baseline age (p=0.673), sex (p=0.645) and low-density lipoprotein cholesterol reduction (p=0.339)., Conclusions: Our updated meta-analysis suggested that PCSK9-mAbs had no significant impact on circulating hs-CRP levels irrespective of PCSK9-mAb types, participant characteristics and treatment duration or methods., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2018. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Cancer therapy has evolved significantly with increased adoption of biologic agents ("biologics"). That evolution is especially true for her2 (human epidermal growth factor receptor-2)-positive breast cancer with the introduction of trastuzumab, a monoclonal antibody against the her2 receptor, which, in combination with chemotherapy, significantly improves survival in both metastatic and early disease. Although the efficacy of biologics is undeniable, their expense is a significant contributor to the increasing cost of cancer care. Across disease sites and indications, biosimilar agents are rapidly being developed with the goal of offering cost-effective alternatives to biologics. Biosimilars are pharmaceuticals whose molecular shape, efficacy, and safety are similar, but not identical, to those of the original product. Although these agents hold the potential to improve patient access, complexities in their production, evaluation, cost, and clinical application have raised questions among experts. Here, we review the landscape of biosimilar agents in oncology, with a focus on trastuzumab biosimilars. We discuss important considerations that must be made as these agents are introduced into routine cancer care.

The CDC Tier 1 select agent Francisella tularensis is a small, Gram-negative bacterium and the causative agent of tularemia, a potentially life-threatening infection endemic in the United States, Europe and Asia. Currently, there is no licensed vaccine or rapid point-of-care diagnostic test for tularemia. The purpose of this research was to develop monoclonal antibodies (mAbs) specific to the F. tularensis surface-expressed lipopolysaccharide (LPS) for a potential use in a rapid diagnostic test. Our initial antigen capture ELISA was developed using murine IgG3 mAb 1A4. Due to the low sensitivity of the initial assay, IgG subclass switching, which is known to have an effect on the functional affinity of a mAb, was exploited for the purpose of enhancing assay sensitivity. The ELISA developed using the IgG1 or IgG2b mAbs from the subclass-switch family of 1A4 IgG3 yielded improved assay sensitivity. However, surface plasmon resonance (SPR) demonstrated that the functional affinity was decreased as a result of subclass switching. Further investigation using direct ELISA revealed the potential self-association of 1A4 IgG3, which could explain the higher functional affinity and higher assay background seen with this mAb. Additionally, the higher assay background was found to negatively affect assay sensitivity. Thus, enhancement of the assay sensitivity by subclass switching is likely due to the decrease in assay background, simply by avoiding the self-association of IgG3.

Background: Growth factor receptor HER3 (ErbB3) lacks standardized immunohistochemistry (IHC)-based methods for formalin-fixed paraffin-embedded (FFPE) tissue samples. We compared 4 different anti-HER3 antibodies to explain the differences found in the staining results reported in the literature., Materials and Methods: Four commercial HER3 antibodies were tested on FFPE samples including mouse monoclonal antibody clones, DAK-H3-IC and RTJ1, rabbit monoclonal antibody clone SP71, and rabbit polyclonal antibody (SAB4500793). Membranous and cytoplasmic staining patterns were analyzed and scored as 0, 1+, or 2+ according to the intensity of the staining and completeness of membranous and cytoplasmic staining. A large collection of HER2-amplified breast cancers (n=177) was stained with the best performing HER3 antibody. The breast cancer cell line, MDA-453, and human prostate tissue were used as positive controls. IHC results were confirmed by analysis of flow cytometry performed on breast cancer cell lines. Staining results of FFPE samples were compared with samples fixed with an epitope-sensitive fixative (PAXgene)., Results: Clear circumferential cell membrane staining was found only with the HER3 antibody clone DAK-H3-IC. Other antibodies (RTJ1, SP71, and polyclonal) yielded uncertain and nonreproducible staining results. In addition to cell membrane staining, DAK-H3-IC was also localized to the cytoplasm, but no nuclear staining was observed. In HER2-amplified breast cancers, 80% of samples were classified as 1+ or 2+ according to the HER3 staining on the cell membrane. The results from FFPE cell line samples were comparable to those obtained from unfixed cells in flow cytometry. IHC conducted on FFPE samples and on PAXgene-fixed samples showed equivalent results., Conclusions: We conclude that IHC with the monoclonal antibody, DAK-H3-IC, on FFPE samples is a reliable staining method for use in translational research. Assessment of membranous HER3 expression may be clinically relevant in selecting patients who may most benefit from pertuzumab or other novel anti-HER3 therapies.

Characterization of unknown monoclonal antibody (mAb) variants is important in order to identify their potential impact on safety, potency, and stability. Ion exchange chromatography (IEC) coupled with UV detection is frequently used to separate and quantify mAb variants in routine quality control (QC). However, characterization of the chromatographic peaks resulting from an IEC separation is an extremely time-consuming process, involving many cumbersome steps. Presented here is an online four-dimensional high performance liquid chromatography-mass spectrometry (4D HPLC/MS) approach, developed to circumvent these limitations. To achieve this, a 2D HPLC system was extended through the introduction of additional modules, hence enabling fully automated bioseparation of mAbs, fractionation of peaks, reduction, tryptic digestion, and reversed-phase (RP) separation of resulting peptides followed by MS detection. The entire separation and analytical process for an unknown peak is performed in less than 1.5 h, leading to a significant time savings, with comparable sequence coverage. To show the comparability with the traditional offline process, a proof of concept study with a previously characterized mAb1 is presented in this paper.

We report a new online capillary isoelectric focusing-mass spectrometry (CIEF-MS) method for monoclonal antibody (mAb) charge variant analysis using an electrokinetically pumped sheath-flow nanospray ion source and a time-of-flight MS with pressure-assisted chemical mobilization. To develop a successful, reliable CIEF-MS method for mAb, we have selected and optimized many critical, interrelating reagents and parameters that include (1) MS-friendly anolyte and catholyte; (2) a glycerol enhanced sample mixture that reduced non-CIEF electrophoretic mobility and band broadening; (3) ampholyte selected for balancing resolution and MS sensitivity; (4) sheath liquid composition optimized for efficient focusing, mobilization, and electrospray ionization; (5) judiciously selected CIEF running parameters including injection amount, field strength, and applied pressure. The fundamental premise of CIEF was well maintained as verified by the linear correlation (R 2 = 0.99) between pI values and migration time using a mixture of pI markers. In addition, the charge variant profiles of trastuzumab, bevacizumab, infliximab, and cetuximab, obtained using this CIEF-MS method, were corroborated by imaged CIEF-UV (iCIEF-UV) analyses. The relative standard deviations (RSD) of absolute migration time of pI markers were all less than 5% (n = 4). Triplicate analyses of bevacizumab showed RSD less than 1% for relative migration time to an internal standard and RSD of 7% for absolute MS peak area. Moreover, the antibody charge variants were characterized using the online intact MS data. To the best of our knowledge, this is the first time that direct online MS detection and characterization were achieved for mAb charge variants resolved by CIEF as indicated by a well-established linear pH gradient and correlated CIEF-UV charge variant profiles.

Objective: The aim of this study was to systemically review the efficacy and safety of inhibitors of interleukin 6 (IL-6): clazakizumab, IL-12/23: ustekinumab, and IL-17A: secukinumab, brodalumab, and ixekizumab in psoriatic arthritis (PsA)., Methods: The literature search was conducted using MEDLINE, EMBASE, Cochrane Library, Scopus, and Web of Science. We included randomized controlled trials that assessed the efficacy of IL inhibitors and reported American College of Rheumatology 20 response at 24 weeks. Meta-analysis was done using random-effects model utilizing the DerSimonian and Laird method. Quality assessment was done using RobotReviewer Cochrane Risk-of-Bias Assessment Tool. Heterogeneity was assessed with Q statistic and quantified with I. Publication bias was assessed with a funnel plot., Results: Eight studies including 2722 subjects demonstrate the efficacy of IL inhibitors clazakizumab, secukinumab, ixekizumab, brodalumab, and ustekinumab in the treatment of PsA. The American College of Rheumatology 20/50/70 risk ratios were 2.02 (95% confidence interval [CI], 1.65-2.47; P = 0.000), 2.95 (95% CI, 2.32-3.73; P = 0.00), and 5.14 (95% CI, 3.28-8.06; P = 0.00), respectively, in favor of treatment versus placebo. There was no evidence of significant heterogeneity between trials. Subgroup analysis showed efficacy in patients who were tumor necrosis factor naive, as well as tumor necrosis factor nonresponders or inadequate responders. The number of adverse events was higher in the treatment groups versus placebo, the majority were mild and did not require treatment adjustment (risk ratio, 1.17; 95% CI, 1.06-1.28; P = 0.001). There was no significant difference in drug withdrawals., Conclusions: Our meta-analysis shows that the inhibitors of IL-6 (clazakizumab), IL-12/23 (ustekinumab), and IL-17A (secukinumab, brodalumab, ixekizumab) are efficacious and generally well tolerated when used to treat patients with PsA.

For research groups needing to isotype a significant number of antibodies on a fairly regular basis, the protocol outlined here provides a cost-effective option. In this simple sandwich ELISA, the monoclonal antibody is first captured with antibodies that discriminate between heavy-chain isotypes and then is detected with antibodies specific for each light chain. This combination ensures that free light chain secreted by hybridomas does not yield a false-positive result, because in a true positive both the capture and detecting antibodies bind the monoclonal antibody., (© 2017 Cold Spring Harbor Laboratory Press.)

The rapidly increasing number of approved monoclonal antibodies (mAbs) and the huge number of mAbs in clinical development are a matter of concern for who wants to easily identify targets, indications, mechanisms of action and possible adverse effects. The current nomenclature being of limited interest, simple rationales will be presented for helping practitioners in rapidly classify mAbs depending on their structure-pharmacology relationship and in evaluating their potential effects, particularly in transfusion medicine., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

An expanding list of immunomodulatory or immunosuppressive monoclonal antibodies (mAbs) and biologic therapeutics is currently entering clinical practice, particularly in the areas of oncology, transplantation and autoimmune disorders. These agents are directed against molecules or cells involved in inflammation and immunity and may therefore be associated with serious and opportunistic infections. The purpose of this review was to critically analyse the literature on invasive fungal infections (IFIs) occurring in association with mAbs and fusion proteins other than tumour necrosis alpha (TNF-α) inhibitors, including therapeutics modulating T-cell-mediated pathologies (muromonab, abatacept, belatacept, ipilimumab, basiliximab, daclizumab), inducing lymphopenia (alemtuzumab), depleting CD20+ B cells (rituximab) and interfering with various targets (anakinra, natalizumab, blodalumab, ixekizumab and others) with a focus on children, and to provide a framework of evaluating the risk for IFIs in this population., (© 2017 Blackwell Verlag GmbH.)

Monoclonal antibodies and other biologic response modifiers have allowed for targeted drug therapy in managing various autoimmune diseases. A number of immune pathways have been exploited in the development of targeted immunomodulatory therapies, including cytokine-directed therapies such as tumor necrosis factor-alpha and interleukins, integrins, B-cells, and co-stimulation modulators. With new targeted therapies in the pipeline, more options are becoming available for treatment of autoimmune diseases. [Full article available at http://rimed.org/rimedicaljournal-2016-12.asp].

Immunofluorescence staining plays a vital role in nephropathology, but the panel of antibodies used has not changed for decades. Further classification of immunoglobulin (Ig)G-containing immune-type deposits with IgG subclass staining (IgG1, IgG2, IgG3, and IgG4) has been shown to be of diagnostic utility in glomerular diseases, but their value in the evaluation of renal biopsies has not been addressed systematically in large renal biopsy material. Between January 2007 and June 2014, using direct immunofluorescence, we stained every renal biopsy for the IgG subclasses if there was moderate to prominent glomerular IgG staining and/or IgG-predominant or IgG-codominant glomerular staining. The total number of biopsies stained was 1084, which included 367 cases of membranous glomerulonephritis, 307 cases of lupus nephritis, 74 cases of fibrillary glomerulonephritis, 53 cases of proliferative glomerulonephritis with monoclonal IgG deposits, and 25 cases of antiglomerular basement membrane disease, among others. We found that monoclonality of IgG deposits cannot always be reliably determined on the basis of kappa and lambda light chain staining alone, particularly if concomitant (frequently nonspecific) IgM staining is present. In IgG heavy and heavy and light chain deposition disease (3 cases), subclass staining is very helpful, and in proliferative glomerulonephritis with monoclonal IgG deposits subclass staining is necessary. IgG subclass staining is useful in differentiating primary from secondary membranous glomerulonephritis. In proliferative glomerulonephritis with polyclonal IgG deposition, IgG1 dominance/codominance with concomitant IgG3 and IgG2 but weak or absent IgG4 staining favors an underlying autoimmune disease. IgG subclass staining is a very useful diagnostic method in a selected cohort of renal biopsies, particularly in biopsies with glomerulonephritis with monoclonal IgG deposits.

Background: Immune checkpoint inhibitors (ICIs) rely on the presence of ongoing immune response to exert their antitumor effect. Little is known whether an age-related decline in immune function negatively influences antitumor response and in so doing diminishes the efficacy of ICIs in elderly subjects. We performed a meta-analysis to compare the efficacy of ICIs between younger and older patients., Patients and Methods: PubMed and the ASCO databases were searched up to September 2015. We included randomized controlled trials (RCTs) of ICIs (ipilimumab, tremelimumab, nivolumab and pembrolizumab) reporting subgroup comparison of overall survival (OS) and/or progression-free survival (PFS) based on age cutoffs. The summary hazard ratio (HR) and 95% confidence interval (CI) were calculated., Results: A total of 5265 patients from nine RCTs of ICI were included. When patients are dichotomized into younger and older groups with an age cut-off of 65-70 years, ICIs improved OS in both younger (HR, 0.75; 95% CI, 0.68-0.82) and older (HR, 0.73; 95% CI, 0.62-0.87) groups. An improvement in PFS was observed in younger (HR, 0.58; 95% CI, 0.40-0.84) and older (HR, 0.77; 95% CI, 0.58-1.01) patients. Subgroup analyses according to ICI and tumor type showed a consistent survival benefit in both younger and older groups except for the subgroup of older patients treated in 4 trials of anti-programmed cell death protein-1 (PD-1) monoclonal antibody (HR, 0.86; 95% CI, 0.41-1.83)., Conclusions: A benefit in OS with ICIs was significant in both younger and older patients with a cut-off age of 65-70 years., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Use of monoclonal antibodies (mAbs) has revolutionized cancer therapy. Approaches targeting specific cellular targets on the malignant cells and in tumor microenvironment have been proved to be successful in hematologic malignancies, including cutaneous lymphomas. mAb-based therapy for cutaneous T-cell lymphoma has demonstrated high response rates and a favorable toxicity profile in clinical trials. Several antibodies and antibody-based conjugates are approved for use in clinical practice, and many more are in ongoing and planned clinical trials. In addition, these safe and effective drugs can be used as pillars for sequential therapies in a rational stepwise manner., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Before 2011, patients with advanced or metastatic melanoma had a particularly poor long-term prognosis. Since traditional treatments failed to confer a survival benefit, patients were preferentially entered into clinical trials of investigational agents. A greater understanding of the epidemiology and biology of disease has underpinned the development of newer therapies, including six agents that have been approved in the EU, US and/or Japan: a cytotoxic T-lymphocyte antigen-4 inhibitor (ipilimumab), two programmed cell death-1 receptor inhibitors (nivolumab and pembrolizumab), two BRAF inhibitors (vemurafenib and dabrafenib) and a MEK inhibitor (trametinib). The availability of these treatments has greatly improved the outlook for patients with advanced melanoma; however, a major consideration for physicians is now to determine how best to integrate these agents into clinical practice. Therapeutic decisions are complicated by the need to consider patient and disease characteristics, and individual treatment goals, alongside the different efficacy and safety profiles of agents with varying mechanisms of action. Long-term survival, an outcome largely out of reach with traditional systemic therapies, is now a realistic goal, creating the additional need to re-establish how clinical benefit is evaluated. In this review we summarise the current treatment landscape in advanced melanoma and discuss the promise of agents still in development. We also speculate on the future of melanoma treatment and discuss how combination and sequencing approaches may be used to optimise patient care in the future., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Trichinella spiralis is an intracellular parasitic nematode of mammalian skeletal muscle, causing a serious zoonotic disease in humans and showing a high economic impact mainly in pig breeding. Serine proteinases of T. spiralis play important roles in the host-parasite interactions mediating host invasion. In this study, we have focused on newborn larvae (NBL-1), the first identified serine proteinase from the NBL stage of T. spiralis. Five monoclonal antibodies (mAbs) directed against the C-terminal part of NBL1, were produced. These mAbs were IgG1κ isotype and specifically recognized as a common motif of 10 amino acids (PSSGSRPTYP). Selected mAbs were further characterized using antigens from various developmental stages of T. spiralis. Western blot revealed that selected mAbs reacted with the native NBL1 at Mr 50 kDa in the adult and NBL mixed antigens and NBL stage alone. Indirect immunofluorescence analysis revealed that selected mAbs intensely stained only the embryos within the gravid females and the NBL. Thus, the produced mAbs are useful tools for the characterization of NBL1 as a major antigen of Trichinella involved in the invasion of the host but also for the development of new serological tests with an early detection of T. spiralis infection.

Influenza A virus infection is a persistent threat to public health worldwide due to hemagglutinin (HA) variation. Current vaccines against influenza A virus provide immunity to viral isolates similar to vaccine strains. Antibodies against common epitopes provide immunity to diverse influenza virus strains and protect against future pandemic influenza. Therefore, it is vital to analyze common HA antigenic epitopes of influenza virus. In this study, 14 strains of monoclonal antibodies with high sensitivity to common epitopes of influenza virus antigens identified in our previous study were selected as the tool to predict common HA epitopes. The common HA antigenic epitopes were divided into four categories by ELISA blocking experiments, and separately, into three categories according to the preliminary results of computer simulation. Comparison between the results of computer simulations and ELISA blocking experiments indicated that at least two classes of common epitopes are present in influenza virus HA. This study provides experimental data for improving the prediction of HA epitopes of influenza virus (H1 subtype) and the development of a potential universal vaccine as well as a novel approach for the prediction of epitopes on other pathogenic microorganisms., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Purpose: Existing health technology assessment methods can be time-consuming and complicated to use in practice. EValuation of pharmaceutical Innovations with regard to Therapeutic Advantage (EVITA) is a recently developed drug assessment strategy that provides a detailed and clinically relevant evaluation of new agents compared to standard therapies. We therefore sought to use EVITA to evaluate eight novel agents recently introduced to clinical practice or in late-stage trials for the treatment of prostate cancer, metastatic melanoma, or systemic lupus erythematosus (SLE)., Methods: Eight agents (abiraterone, enzalutamide, sipuleucel-T, Prostvac, radium 223, ipilimumab, vemurafenib, and belimumab) were selected for study using the EVITA algorithm. A comprehensive literature search was performed to find clinical trial data, which were then classified using the EVITA protocol. EVITA was also compared to results from health technology assessments (HTAs) or reimbursement decisions., Results: The EVITA scores for the eight drugs ranged from 5.5 to 9: all the selected agents are therefore classed as 'recommended' and are likely to produce a therapeutic advantage. In particular, vemurafenib is likely to be highly beneficial to patients with metastatic melanoma and radium 223 to patients with metastatic prostate cancer affecting the bone. The EVITA results were generally concordant with HTAs., Conclusions: All the agents show favourable EVITA scores and are therefore recommended for clinical practice. EVITA is an easy-to-use tool that provides clinical context to the assessment of newly introduced agents and can be easily used by non-specialists.

The chaperonin protein GroEL, also known as heat shock protein 60 (Hsp60), is a prominent antigen in the human and mouse antibody response to the facultative intracellular bacterium Francisella tularensis (Ft), the causative agent of tularemia. In addition to its presumed cytoplasmic location, FtGroEL has been reported to be a potential component of the bacterial surface and to be released from the bacteria. In the current study, 13 IgG2a and one IgG3 mouse monoclonal antibodies (mAbs) specific for FtGroEL were classified into eleven unique groups based on shared VH-VL germline genes, and seven crossblocking profiles revealing at least three non-overlapping epitope areas in competition ELISA. In a mouse model of respiratory tularemia with the highly pathogenic Ft type A strain SchuS4, the Ab64 and N200 IgG2a mAbs, which block each other's binding to and are sensitive to the same two point mutations in FtGroEL, reduced bacterial burden indicating that they target protective GroEL B-cell epitopes. The Ab64 and N200 epitopes, as well as those of three other mAbs with different crossblocking profiles, Ab53, N3, and N30, were mapped by hydrogen/deuterium exchange-mass spectrometry (DXMS) and visualized on a homology model of FtGroEL. This model was further supported by its experimentally-validated computational docking to the X-ray crystal structures of Ab64 and Ab53 Fabs. The structural analysis and DXMS profiles of the Ab64 and N200 mAbs suggest that their protective effects may be due to induction or stabilization of a conformational change in FtGroEL.

A crucial step in the development of therapeutic monoclonal antibodies is the selection of robust pharmaceutical candidates and screening of efficacious protein formulations to increase the resistance toward physicochemical degradation and aggregation during processing and storage. Here, we introduce small-angle X-ray scattering (SAXS) to characterize antibody solution behavior, which strongly complements conventional biophysical analysis. First, we apply a variety of conventional biophysical techniques for the evaluation of structural, conformational, and colloidal stability and report a systematic comparison between designed humanized IgG1, IgG2, and IgG4 with identical variable regions. Then, the high information content of SAXS data enables sensitive detection of structural differences between three IgG subclasses at neutral pH and rapid formation of dimers of IgG2 and IgG4 at low pH. We reveal subclass-specific variation in intermolecular repulsion already at low and medium protein concentrations, which explains the observed improved stability of IgG1 with respect to aggregation. We show how excipients dramatically influence such repulsive effects, hence demonstrating the potential application of extensive SAXS screening in antibody selection, eventual engineering, and formulation development., (© 2014 The Authors. Journal of Pharmaceutical Sciences published by Wiley Periodicals, Inc. and the American Pharmacists Association.)

The diversity of a panel of antibodies that target a specific antigen can be established in various assay formats. In conventional epitope binning assays purified antibodies are tested in a pairwise manner: two antibodies that compete with each other for binding to an antigen are grouped into the same cluster or bin, while they are assigned to two different clusters when they do not compete. Here we present a high through put assay that enables grouping of crude hybridoma supernatants without a need for antibody purification. In addition, the assay does not require recombinant protein, because it is conducted on cells that express the antigen of interest. Hence, one can use the antibody-clustering assay for cell surface proteins that are not amenable to purification. Heavy chain variable region (VH) sequencing shows that VH composition within clusters is conserved. Finally, the assay is in good agreement with a conventional epitope binning assay with purified antigen., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In a relatively short period of time, monoclonal antibodies have entered the mainstream of cancer therapy. Their first use was as antagonists of oncogenic receptor tyrosine kinases, but today monoclonal antibodies have emerged as long-sought vehicles for the targeted delivery of potent chemotherapeutic agents and as powerful tools to manipulate anticancer immune responses. With ever more promising results from the clinic, the future will likely see continued growth in the discovery and development of therapeutic antibodies and their derivatives.

Monoclonal antibodies (mAb) have become a mainstay in tumor therapy. Clinical responses to mAb therapy, however, are far from optimal, with many patients presenting native or acquired resistance or suboptimal responses to a mAb therapy. MAbs exert antitumor activity through different mechanisms of action and we propose here a classification of these mechanisms. In many cases mAbs need to interact with immune cells to exert antitumor activity. We summarize evidence showing that interactions between mAbs and immune cells may be inadequate for optimal antitumor activity. This may be due to insufficient tumor accumulation of mAbs or immune cells, or to low-affinity interactions between these components. The possibilities to improve tumor accumulation of mAbs and immune cells, and to improve the affinity of the interactions between these components are reviewed. We also discuss future directions of research that might further improve the therapeutic efficacy of antitumor mAbs.

Aim: Preparation of H1 subtype of influenza virus HA protein monoclonal antibody (mAbs), and to analyse their reactivity., Methods: H1N1 influenza virus vaccine (2009) and seasonal A1 influenza virus vaccine as antigen, conventional immunization, fusion, cloning, access to the antigen-specific mAbs. To study the reactivity and specificity of mAbs by ELISA, HI test and Western blot., Results: We have obtained 97 hybridoma of stable secreting anti-H1 subtype of influenza virus HA protein. According to their different reactivity, these mAbs can be divided into four categories: 39 strains for strain-specific, of which 29 have HI activity; 7 strains for subtype-specific, of which 5 have HI activity; 16 strains for the 2009 pandemic strain and the seasonal strains to common antigens, of which 9 have HI activity; 35 strains common for influenza virus antigens, of which 22 have HI activity., Conclusion: Both vaccines have better immunogenicity and immune protection activity. Preparation of four types antibody against HA protein of H1 subtype of influenza virus, can provide experimental data for preparation subtype-specific diagnostic kits and influenza A and B virus diagnostic kit, and lay a foundation for further studying of H1N1 influenza virus HA epitope.

Protein-based therapeutics are highly successful in clinic and currently enjoy unprecedented recognition of their potential. More than 100 genuine and similar number of modified therapeutic proteins are approved for clinical use in the European Union and the USA with 2010 sales of US$108 bln; monoclonal antibodies (mAbs) accounted for almost half (48%) of the sales. Based on their pharmacological activity, they can be divided into five groups: (a) replacing a protein that is deficient or abnormal; (b) augmenting an existing pathway; (c) providing a novel function or activity; (d) interfering with a molecule or organism; and (e) delivering other compounds or proteins, such as a radionuclide, cytotoxic drug, or effector proteins. Therapeutic proteins can also be grouped based on their molecular types that include antibody-based drugs, Fc fusion proteins, anticoagulants, blood factors, bone morphogenetic proteins, engineered protein scaffolds, enzymes, growth factors, hormones, interferons, interleukins, and thrombolytics. They can also be classified based on their molecular mechanism of activity as (a) binding non-covalently to target, e.g., mAbs; (b) affecting covalent bonds, e.g., enzymes; and (c) exerting activity without specific interactions, e.g., serum albumin. Most protein therapeutics currently on the market are recombinant and hundreds of them are in clinical trials for therapy of cancers, immune disorders, infections, and other diseases. New engineered proteins, including bispecific mAbs and multispecific fusion proteins, mAbs conjugated with small molecule drugs, and proteins with optimized pharmacokinetics, are currently under development. However, in the last several decades, there are no conceptually new methodological developments comparable, e.g., to genetic engineering leading to the development of recombinant therapeutic proteins. It appears that a paradigm change in methodologies and understanding of mechanisms is needed to overcome major challenges, including resistance to therapy, access to targets, complexity of biological systems, and individual variations.

Biological medicines are a heterogeneous group of drugs that are produced by living organisms using genetic or biological technology. Unlike chemically derived small molecules biologics are structurally complex making characterization and manufacturing difficult. Moreover, biological medicines show a great variety concerning their clinical use. To appropriately consider these particularities, there are other standards and guidelines for approval of similar derivatives of biologics, the so-called biosimilars or follow-on biologics. In contrast to a generic medicinal product containing a chemically identical active ingredient, a biosimilar is only expected to be similar to the innovator drug. Nowadays, monoclonal antibodies, fragments of antibodies, and fusion proteins manufactured by recombinant procedures play an important role. They have been used in many specialties for diagnostic and therapeutic purposes and are subject to continuous further development and improvement. Their nomenclature is based on a classification by the WHO which allows drawing conclusions for class of substance, origin, and pharmacological target.

Motivation: Monoclonal antibodies (mAbs) are among the most powerful and important tools in biology and medicine. MAb development is of great significance to many research and clinical applications. Therefore, objective mAb classification is essential for categorizing and comparing mAb panels based on their reactivity patterns in different cellular species. However, typical flow cytometric mAb profiles present unique modeling challenges with their non-Gaussian features and intersample variations. It makes accurate mAb classification difficult to do with the currently used kernel-based or hierarchical clustering techniques., Results: To address these challenges, in the present study we developed a formal two-step framework called mAbprofiler for systematic, parametric characterization of mAb profiles. Further, we measured the reactivity of hundreds of new antibodies in diverse tissues using flow cytometry, which we successfully classified using mAbprofiler. First, mAbprofiler fits a mAb's flow cytometric histogram with a finite mixture model of skew t distributions that is robust against non-Gaussian features, and constructs a precise, smooth and mathematically rigorous profile. Then it performs novel curve clustering of the fitted mAb profiles using a skew t mixture of non-linear regression model that can handle intersample variation. Thus, mAbprofiler provides a new framework for identifying robust mAb classes, all well defined by distinct parametric templates, which can be used for classifying new mAb samples. We validated our classification results both computationally and empirically using mAb profiles of known classification., Availability and Implementation: A demonstration code in R is available at the journal website. The R code implementing the full framework is available from the author website - http://amath.nchu.edu.tw/www/teacher/tilin/software, Contact: saumyadipta&#95;pyne@dfci.harvard.edu, Supplementary Information: Supplementary data are available at Bioinformatics online.

CD20 is a cell-surface marker of normal and malignant B cells. Rituximab, a monoclonal antibody targeting CD20, has improved the treatment of malignant lymphomas. Therapeutic CD20 antibodies are classified as either type I or II based on different mechanisms of killing malignant B cells. To reveal the molecular basis of this distinction, we fine-mapped the epitopes recognized by both types. We also determined the first X-ray structure of a type II antibody by crystallizing the obinutuzumab (GA101) Fab fragment alone and in complex with a CD20 cyclopeptide. Despite recognizing an overlapping epitope, GA101 binds CD20 in a completely different orientation than type I antibodies. Moreover, the elbow angle of GA101 is almost 30° wider than in type I antibodies, potentially resulting in different spatial arrangements of 2 CD20 molecules bound to a single GA101 or rituximab molecule. Using protein tomography, different CD20 complexes were found to be associated with the 2 antibodies, and confocal microscopy showed different membrane compartmentalization of these subpopulations of the cellular CD20 pool. Our findings offer a possible molecular explanation for the different cellular responses elicited by type I and II antibodies.

The anti-CD20 monoclonal antibody rituximab has revolutionized the treatment of patients with follicular B-cell lymphoma. With the combination of chemotherapy and rituximab the overall survival rate has increased with approximately 30%. Unfortunately, there is resistance to rituximab with relapse of the disease in about 60% of the patients during the first five years of treatment and eventually in all patients. To this end, there is a need to develop improved anti-CD20 monoclonal antibodies and antibodies that target other attractive molecules expressed on the follicular lymphoma cell. This review describes the development and clinical achievements so far of next generation anti-CD20 and other antibodies in the treatment of follicular B-cell lymphoma., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The ability to select antibodies with stable thermodynamic profiles can greatly enhance the performance of point-of-care (POC) devices allowing reproducible "on-the-spot" analysis for markers of clinical and environmental relevance. We show that by ranking antibodies based on their kinetic profiles at two different temperatures, greater information content is acquired, facilitating the selection of antibodies with desired binding characteristics. Observed binding patterns highlight the importance of temperature to assay design, which should be fully taken into consideration to ensure that the appropriate antibody is selected for the desired test., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Mycobacterium contains several immunologically active substances, which play a principal role in mycobacterial diseases. The majority of the highly antigenic proteins present in mycobacterial homogenates are components of the A60 complex. In this study, A60 antigen was prepared from cytoplasm of Mycobacterium bovis Bacillus Calmette-Guerin (BCG). Cytoplasm was fractionated by passage through the column of sepharose 6B and ConA-sepharose 4B. After purification of spleen cells of the immunized mice, the cells were fused with SP2/0 myeloma cells. Four clone cell lines producing antibody against A60 antigens were established and each clone was tested for immunoreactivity against purified A60 by ELISA and immunoblotting. The clone designated DEB7 reacted strongly with A60. Immunoblotting using MAb DEB7 showed that this MAb binds to a single protein of A60 subunit with a molecular weight of 65 kDa. This subunit of A60 M. bovis recognized by DEB7 MAb could be used to increase the sensitivity and specificity of immunoassay or other potential roles in mycobacterium infection.