Targeted anti-cancer therapy using rituximab, a chimaeric anti-CD20 antibody (IDEC-C2B8) in the treatment of non-Hodgkin's B-cell lymphoma

Immune checkpoint inhibitors associated thyroiditis: mechanisms and clinical outcomes

Background Immune checkpoint inhibitors (ICI) have revolutionized cancer treatment improving prognosis in many cancers. However, ICI often trigger immune-related adverse events (irAEs) that can affect various organ systems, leading to significant clinical challenges. The most frequent irAEs are those affecting the endocrine glands, reported in approximately 10% of treated patients. Thyroid dysfunction is the most common endocrine irAEs, mainly associated with PD-1/PD-L1 blockade therapies. Transient asymptomatic thyrotoxicosis is the most common form of clinical presentation, often followed by hypothyroidism. Interestingly, several studies have demonstrated that irAEs correlate with the response to cancer therapy and with improved overall survival (OS). The mechanisms underlying thyroid irAEs are not fully elucidated but complex interactions between genetic predisposition to thyroid autoimmunity, distinct immune mechanisms and thyroid cell intrinsic mechanisms are thought to drive thyroiditis associated with ICI therapy. Purpose In this review we discuss the latest data on clinical features of thyroid irAEs, proposed mechanisms and their association with improved survival.

A systematic review of the safety and efficacy of monoclonal antibodies for progressive multiple sclerosis

BACKGROUND

Progressive multiple sclerosis (PMS) is a debilitating condition characterized by progressively worsening symptoms. Monoclonal antibodies are novel therapies for MS, but their safety and efficacy in the progressive form have not been comprehensively studied. In this systematic review, we aimed to evaluate the available evidence regarding monoclonal antibody treatment for PMS.

METHODS

After registration of the study protocol in PROSPERO, we systematically searched three major databases for clinical trials involving monoclonal antibodies administration for PMS treatment. All the retrieved results were imported into the EndNote reference manager. After removing the duplicates, two independent researchers did the study selection and data extraction. The risk of bias was assessed using the Joanna Briggs Institute (JBI) checklist.

RESULTS

Of the 1846 studies in the preliminary search, 13 clinical trials investigating monoclonal antibodies (Ocrelizumab, Natalizumab, Rituximab, and Alemtuzumab) in PMS patients were included. Ocrelizumab was significantly effective in reducing clinical disease progression measures in primary PMS patients. The results for Rituximab were not completely reassuring and only showed significant changes for some endpoints on MRI and clinical measures. Natalizumab decreased the relapse rate and improved MRI features for secondary PMS patients, but not clinical endpoints. The studies on Alemtuzumab treatment revealed conflicting outcomes, with improvements observed in MRI endpoints but clinical worsening in patients. Additionally, among the studied adverse events, upper respiratory infections, urinary tract infections, and nasopharyngitis were frequently reported.

CONCLUSION

Based on our findings, Ocrelizumab is the most efficient monoclonal antibody for primary PMS, although it is associated with a higher risk of infection. While other monoclonal antibodies did not show significant promise in treating PMS, more research is necessary.

Functional antibody delivery: Advances in cellular manipulation

The current therapeutic antibody market in the U.S. consists of 100 antibody-based products and their market value is expected to explode beyond $300 billion by 2025. These therapies are presently limited to extracellular targets due to the innate inability of antibodies to transverse membranes. To expand the number of accessible therapeutic targets, intracellular antibody delivery is necessary. Many delivery vehicles for antibodies have been used with some promising results, such as nanoparticles and cell penetrating polymers. Despite the success of these delivery platforms using model antibody cargo, there is a surprisingly small number of studies that focus on functional antibody delivery into the cytosol that also measures a cellular response. Antibodies can be designed for essentially unlimited targets, including proteins and DNA, that will ultimately control cell function once delivered inside cells. Advancement in cellular manipulation depends on the application of intracellularly delivering functional antibodies to achieve a desired result. This review focuses on the emerging field of functional antibody delivery which enables various cellular responses and cell manipulation.

Ocrelizumab effect on humoral and cellular immunity in multiple sclerosis and its clinical correlates: a 3-year observational study

OBJECTIVE

We aim to evaluate 3-year effects of ocrelizumab (humanized anti-CD20 monoclonal antibody for the treatment of multiple sclerosis (MS)) on lymphocytes, neutrophils and immunoglobulins: (1) when compared with pre-infusion assessment; (2) over the course of treatment; and (3) possible clinical correlates of the observed immunological modifications.

METHODS

This real-world observational cohort study has been conducted on prospectively collected data from 78 MS patients (mean age 47.8 ± 10.5 years; females 48.7%) commencing on ocrelizumab from 2018, with mean follow-up of 36.5 ± 6.8 months. Clinical data and blood samples were collected every three months. Total lymphocyte count and subpopulations were assessed on peripheral blood using flow cytometry. Serum immunoglobulins were evaluated with nephelometry.

RESULTS

When compared with pre-infusion values, we observed reduction of total, CD19 and CD20 lymphocyte counts; however, after the first infusion, their levels remained substantially stable. Over time we observed a progressive reduction of CD8 lymphocytes, while no changes were observed for CD4, CD27, CD3CD27, and CD19CD27. After the first infusion, we observed reduction in IgG, which further decreased during the follow-up. Higher probability of EDSS progression was associated with reduced modulation of CD8 lymphocytes.

INTERPRETATION

Ocrelizumab affects both humoral and cellular immune responses. Disability progression over the follow-up was associated with lower CD8 cytotoxic T-lymphocyte reduction. Changes in humoral response are immediate and sustained, while modulation of cellular immunity occurs progressively through regular re-treatment, and is related to clinical stability.

Neutropenia in Cynomolgus Monkeys With Anti-Drug Antibodies Associated With Administration of Afucosylated Humanized Monoclonal Antibodies

Removal of the core fucose from the Fc region of humanized monoclonal antibodies (afucosylated antibodies) enhances their antibody-dependent cell cytotoxicity activities in killing cancer cells. Based on the authors' experience and literature, administrations of afucosylated antibodies have been associated with neutropenia in cynomolgus monkeys. However, in a recent general toxicology study conducted with an afucosylated antibody in cynomolgus monkeys, transient neutropenia was observed and correlated with the emergence of anti-drug antibodies (ADAs) in the affected animals. To further explore the relationship between neutropenia, afucosylated antibodies, and ADAs in cynomolgus monkeys, we performed an investigational retrospective meta-analysis of data from general toxicology studies conducted with Genentech's therapeutic antibodies administered to cynomolgus monkeys between 2005 and 2021. In this analysis, transient neutropenia strongly correlated with ADA-induced inflammation in cynomolgus monkeys administered afucosylated antibodies. This may reflect the simultaneous occurrence of two distinct processes of neutrophil elimination and utilization, thus overwhelming bone marrow reserve capacity leading to transient neutropenia. The integrated analysis of immunogenicity, and anatomic and clinical pathology results from these studies highlights the correlation of transient neutropenia in cynomolgus monkeys with ADA-related inflammation, potentially exacerbated by enhanced effector function of afucosylated antibodies.

The molecular rationale for the combination of polatuzumab vedotin plus rituximab in diffuse large B-cell lymphoma

Polatuzumab vedotin (Pola) is an antibody-drug conjugate that targets the B-cell antigen CD79b and delivers monomethyl auristatin E (MMAE). It is approved in combination with bendamustine and rituximab (Rit) for relapsed/refractory diffuse large B-cell lymphoma (r/r DLBCL). Understanding the molecular basis of Pola combination therapy with Rit, the key component for the treatment of DLBCL, is important to establish the effective treatment strategies against r/r DLBCL. Here, we examined the rationale for the combination of Pola with Rit using Pola-refractory cells. We found that treatment with Pola increased CD20 expression and sensitivity to Rit-induced complement-dependent cytotoxicity (CDC) in several Pola-refractory cells. Pola treatment increased phosphorylation of AKT and ERK and both AKT- and MEK-specific inhibitors attenuated the Pola-induced increase of CD20 and CDC sensitivity, suggesting that these phosphorylation events were required for this combination efficacy. It was revealed that anti-CD79b antibody increased the phosphorylation of AKT but inhibited the phosphorylation of ERK. In contrast, MMAE potentiated phosphorylation of ERK but slightly attenuated the phosphorylation of AKT. Pola also increased CD20 expression on Pola-refractory xenografted tumours and significantly enhanced antitumour activity in combination with Rit. In conclusion, these results could provide a novel rationale for the combination of Pola plus Rit.

Curcumin: reclaiming the lost ground against cancer resistance

Curcumin, a polyphenol, has a wide range of biological properties such as anticancer, antibacterial, antitubercular, cardioprotective and neuroprotective. Moreover, the anti-proliferative activities of Curcumin have been widely studied against several types of cancers due to its ability to target multiple pathways in cancer. Although Curcumin exhibited potent anticancer activity, its clinical use is limited due to its poor water solubility and faster metabolism. Hence, there is an immense interest among researchers to develop potent, water-soluble, and metabolically stable Curcumin analogs for cancer treatment. While drug resistance remains a major problem in cancer therapy that renders current chemotherapy ineffective, curcumin has shown promise to overcome the resistance and re-sensitize cancer to chemotherapeutic drugs in many studies. In the present review, we are summarizing the role of curcumin in controlling the proliferation of drug-resistant cancers and development of curcumin-based therapeutic applications from cell culture studies up to clinical trials.

2021 update on thyroid-associated ophthalmopathy

PURPOSE

Our understanding of thyroid-associated ophthalmopathy (TAO, A.K.A Graves' orbitopathy, thyroid eye disease) has advanced substantially, since one of us (TJS) wrote the 2010 update on TAO, appearing in this journal.

METHODS

PubMed was searched for relevant articles.

RESULTS

Recent insights have resulted from important studies conducted by many different laboratory groups around the World. A clearer understanding of autoimmune diseases in general and TAO specifically emerged from the use of improved research methodologies. Several key concepts have matured over the past decade. Among them, those arising from the refinement of mouse models of TAO, early stage investigation into restoring immune tolerance in Graves' disease, and a hard-won acknowledgement that the insulin-like growth factor-I receptor (IGF-IR) might play a critical role in the development of TAO, stand out as important. The therapeutic inhibition of IGF-IR has blossomed into an effective and safe medical treatment. Teprotumumab, a β-arrestin biased agonist monoclonal antibody inhibitor of IGF-IR has been studied in two multicenter, double-masked, placebo-controlled clinical trials demonstrated both effectiveness and a promising safety profile in moderate-to-severe, active TAO. Those studies led to the approval by the US FDA of teprotumumab, currently marketed as Tepezza for TAO. We have also learned far more about the putative role that CD34+ fibrocytes and their derivatives, CD34+ orbital fibroblasts, play in TAO.

CONCLUSION

The past decade has been filled with substantial scientific advances that should provide the necessary springboard for continually accelerating discovery over the next 10 years and beyond.

The Therapeutic Landscape of Rheumatoid Arthritis: Current State and Future Directions

Rheumatoid arthritis (RA) is a debilitating autoimmune disease with grave physical, emotional and socioeconomic consequences. Despite advances in targeted biologic and pharmacologic interventions that have recently come to market, many patients with RA continue to have inadequate response to therapies, or intolerable side effects, with resultant progression of their disease. In this review, we detail multiple biomolecular pathways involved in RA disease pathogenesis to elucidate and highlight pathways that have been therapeutic targets in managing this systemic autoimmune disease. Here we present an up-to-date accounting of both emerging and approved pharmacological treatments for RA, detailing their discovery, mechanisms of action, efficacy, and limitations. Finally, we turn to the emerging fields of bioengineering and cell therapy to illuminate possible future targeted therapeutic options that combine material and biological sciences for localized therapeutic action with the potential to greatly reduce side effects seen in systemically applied treatment modalities.

Cancer T-cell therapy: building the foundation for a cure

T-cell cancer therapy is a clinical field flush with opportunity.  It is part of the revolution in immuno-oncology, most apparent in the dramatic clinical success of PD-1/CTLA-4 antibodies and chimeric antigen receptor T-cells (CAR-Ts) to cure certain melanomas and lymphomas, respectively.  Therapeutics based on T cells ultimately hold more promise because of their capacity to carry out complex behaviors and their ease of modification via genetic engineering.  But to overcome the substantial obstacles of effective solid-tumor treatment, T-cell therapy must access novel molecular targets or exploit existing ones in new ways.  As always, tumor selectivity is the key. T-cell therapy has the potential to address target opportunities afforded by its own unique capacity for signal integration and high sensitivity.  With a history of breathtaking innovation, the scientific foundation for the cellular modality has often been bypassed in favor of rapid advance in the clinic.  This situation is changing, as the mechanistic basis for activity of CAR-Ts and TCR-Ts is backfilled by painstaking, systematic experiments—harking back to last century’s evolution and maturation of the small-molecule drug discovery field.   We believe this trend must continue for T-cell therapy to reach its enormous potential.  We support an approach that integrates sound reductionist scientific principles with well-informed, thorough preclinical and translational clinical experiments.

Hypertensive Cardiotoxicity in Cancer Treatment-Systematic Analysis of Adjunct, Conventional Chemotherapy, and Novel Therapies-Epidemiology, Incidence, and Pathophysiology

Cardiotoxicity is the umbrella term for cardiovascular side effects of cancer therapies. The most widely recognized phenotype is left ventricular dysfunction, but cardiotoxicity can manifest as arrhythmogenic, vascular, myocarditic and hypertensive toxicities. Hypertension has long been regarded as one of the most prevalent and modifiable cardiovascular risk factors in the general population, but its relevance during the cancer treatment journey may be underestimated. Hypertensive cardiotoxicity occurs de novo in a substantial proportion of treated cancer patients. The pathology is incompletely characterized—natriuresis and renin angiotensin system interactions play a role particularly in conventional treatments, but in novel therapies endothelial dysfunction and the interaction between the cancer and cardiac kinome are implicated. There exists a treatment paradox in that a significant hypertensive response not only mandates anti-hypertensive treatment, but in fact, in certain cancer treatment scenarios, hypertension is a predictor of cancer treatment efficacy and response. In this comprehensive review of over 80,000 patients, we explored the epidemiology, incidence, and mechanistic pathophysiology of hypertensive cardiotoxicity in adjunct, conventional chemotherapy, and novel cancer treatments. Conventional chemotherapy, adjunct treatments, and novel targeted therapies collectively caused new onset hypertension in 33–68% of treated patients. The incidence of hypertensive cardiotoxicity across twenty common novel therapies for any grade hypertension ranged from 4% (imatinib) to 68% (lenvatinib), and high grade 3 or 4 hypertension in <1% (imatinib) to 42% (lenvatinib). The weighted average effect was all-grade hypertension in 24% and grade 3 or 4 hypertension in 8%.

The Role of Syk in Inflammatory Response of Human Abdominal Aortic Aneurysm Tissue

Objective: Inflammatory response is central to pathogenesis of abdominal aortic aneurysm (AAA). Recently, we reported that Syk, a signaling molecule in inflammatory cells, promotes AAA development in a mouse model. In this study, we aimed to investigate the role of Syk in human AAA pathogenesis.

Materials and Methods: We obtained human AAA wall samples during open surgical aortic repair at Kurume University Hospital. Immunohistochemical analyses of AAA samples were performed for Syk activation and cell type markers. Ex vivo culture of human AAA tissue was utilized to evaluate the effect of P505-15, a Syk inhibitor, on secretions of interleukin-6 (IL-6) and matrix metalloproteinases (MMPs).

Results: Immunohistochemical analysis showed infiltration of B cells, T cells, and macrophages in AAA samples. Syk activation was localized mainly in B cells and part of macrophages. AAA tissue in culture secreted IL-6, MMP-9, and MMP-2 without any stimulation. The unstimulated secretions of IL-6, MMP-9, and MMP-2 were insensitive to P505-15. Secretions of IL-6 and MMP-9 were enhanced by exogenous normal human immunoglobulin G (IgG), which was suppressed by P505-15, whereas secretion of MMP-2 was insensitive to IgG or P505-15.

Conclusion: These results demonstrate an important role of Syk for IgG-dependent inflammatory response in human AAA.

Multiple sclerosis - the remarkable story of a baffling disease

Multiple sclerosis has always been an enigma to its sufferers, their families, medical investigators, and clinicians. For many centuries, there have been attempts to understand its causes and nature, and to discover treatment methods. In the Middle Ages, the disease was claimed to be sent directly from God. A significant development in exploring multiple sclerosis took place in the 19th century, when Jean-Martin Charcot and his colleagues distinguished the disease, precisely described its symptoms, attempted to explain its pathophysiology, and introduced the first methods of symptomatic treatment. The 20th century was a period of discovery and development of diagnostic techniques, such as cerebrospinal fluid analysis, evoked potentials, and magnetic resonance imaging as well as an era of introducing steroid therapy for acute treatment. Currently, the dynamic development of disease modifying therapy and neuroimaging can be observed. The paper aims to delve into the remarkable history of multiple sclerosis by focusing on the earliest case reports and discovery of the disease and exploring its nature, diagnostic methods, and treatment.

Tumour associated glycans: A route to boost immunotherapy?

While the development of immunotherapies for cancer treatment offer significant promise across several cancers, still only a small subset of patients respond to immune based monotherapies. As such, attention has turned to the development of combination therapies. These use conventional cancer treatments such as chemotherapy to sensitise tumours to immunotherapy. Here, we summarise key research, highlighting the exciting potential of tumour associated glycans as therapeutic targets to sensitise tumours to immunotherapy. When cells undergo carcinogenesis they reprogram their glyco-code. Several cancer associated glycans have been identified, and therapies targeting them are under development. Proteins containing carbohydrate binding domains (lectins) are expressed by many immune cell subtypes, and upon glycan binding, transduce immune modulatory signals that regulate the tumour immune microenvironment.

Influence of the bispecific antibody IgG subclass on T cell redirection

T cell redirection mediated by bispecific antibodies (BsAbs) is a promising cancer therapy. Dual antigen binding is necessary for potent T cell redirection and is influenced by the structural characteristics of a BsAb, which are dependent on its IgG subclass. In this study, model BsAbs targeting CD19xCD3 were generated in variants of IgG1, IgG2, and IgG4 carrying Fc mutations that reduce FcγR interaction, and two chimeric IgG subclasses termed IgG1:2 and IgG4:2, in which the IgG1- or IgG4-F(ab)2 are grafted on an IgG2 Fc. Molecules containing an IgG2 or IgG4-F(ab)2 domain were confirmed to be the most structurally compact molecules. All BsAbs were shown to bind both of their target proteins (and corresponding cells) equally well. However, CD19xCD3 IgG2 did not bind both antigens simultaneously as measured by the absence of cellular clustering of T cells with target cells. This translated to a reduced potency of IgG2 BsAbs in T-cell redirection assays. The activity of IgG2 BsAbs was fully restored in the chimeric subclasses IgG4:2 and IgG1:2. This confirmed the major contribution of the F(ab)2 region to the BsAb's functional activity and demonstrated that function of BsAbs can be modulated by engineering molecules combining different Fc and F(ab)2 domains. Abbreviations: ADCC: Antibody-dependent cellular cytotoxicity; AlphaScreenTM: Amplified Luminescent Proximity Homogeneous Assay Screening; ANOVA: Analysis of variance; BiTE: bispecific T-cell engager; BSA: bovine serum albumin; BsAb: bispecific antibody; cFAE: controlled Fab-arm exchange; CDC: complement-dependent cellular cytotoxicity; CIEX: cation-exchange; CIR: chimeric immune receptor; DPBS: Dulbecco's phosphate-buffered saline; EC50 value: effective concentration to reach half-maximum effect; EGFR: epidermal growth factor receptor; EI: expansion index (RAt=x/RAt=0); FACS: fluorescence-activated cell sorting; FVD: fixable viability dye; HI-HPLC: hydrophobic interaction HPLC; HI-FBS: heat-inactivated fetal bovine serum; HPLC: high-pressure liquid chromatography; IC50 value: effective concentration to reach half-maximum inhibition; IQ: Inhibition Quotient; IS: immunological synapse; MES: 2-(N-morpholino)ethanesulfonic acid; R-PE: recombinant phycoerythrin; RA: red area in μm2/well; RD: receptor density; RFP: red fluorescent protein; Rg: radius of gyration; RSV: respiratory syncytial virus; SAXS: small-angle x-ray scattering; scFv: single-chain variable fragment; SD: standard deviation; SPR: surface plasmon resonance; WT: wild-type.

Biological Therapy of Hematologic Malignancies: Toward a Chemotherapy- free Era

Less than 70 years ago, the vast majority of hematologic malignancies were untreatable diseases with fatal prognoses. The development of modern chemotherapy agents, which had begun after the Second World War, was markedly accelerated by the discovery of the structure of DNA and its role in cancer biology and tumor cell division. The path travelled from the first temporary remissions observed in children with acute lymphoblastic leukemia treated with single-agent antimetabolites until the first cures achieved by multi-agent chemotherapy regimens was incredibly short. Despite great successes, however, conventional genotoxic cytostatics suffered from an inherently narrow therapeutic index and extensive toxicity, which in many instances limited their clinical utilization. In the last decade of the 20th century, increasing knowledge on the biology of certain malignancies resulted in the conception and development of first molecularly targeted agents designed to inhibit specific druggable molecules involved in the survival of cancer cells. Advances in technology and genetic engineering enabled the production of structurally complex anticancer macromolecules called biologicals, including therapeutic monoclonal antibodies, antibody-drug conjugates and antibody fragments. The development of drug delivery systems (DDSs), in which conventional drugs were attached to various types of carriers including nanoparticles, liposomes or biodegradable polymers, represented an alternative approach to the development of new anticancer agents. Despite the fact that the antitumor activity of drugs attached to DDSs was not fundamentally different, the improved pharmacokinetic profiles, decreased toxic side effects and significantly increased therapeutic indexes resulted in their enhanced antitumor efficacy compared to conventional (unbound) drugs. Approval of the first immune checkpoint inhibitor for the treatment of cancer in 2011 initiated the era of cancer immunotherapy. Checkpoint inhibitors, bispecific T-cell engagers, adoptive T-cell approaches and cancer vaccines have joined the platform so far, represented mainly by recombinant cytokines, therapeutic monoclonal antibodies and immunomodulatory agents. In specific clinical indications, conventional drugs have already been supplanted by multi-agent, chemotherapy-free regimens comprising diverse immunotherapy and/or targeted agents. The very distinct mechanisms of the anticancer activity of new immunotherapy approaches not only call for novel response criteria, but might also change fundamental treatment paradigms of certain types of hematologic malignancies in the near future.

A non-covalent antibody complex for the delivery of anti-cancer drugs

Antibody drug conjugates (ADCs), which are obtained by coupling a potent cytotoxic agent to a monoclonal antibody (mAb), are traditionally bound in a random way to lysine or cysteine residues, with the final product's heterogeneity having an important impact on their activity, characterization, and manufacturing. A new antibody drug delivery system (ADS) based on a non-covalent linkage between a Fc-binding protein, in this case Protein A or Protein G, and a mAb was investigated in the effort to achieve greater homogeneity and to create a versatile and adaptable drug delivery system. Recombinant staphylococcal Protein A and streptococcal Protein G were chemically PEGylated at the N-terminus with a 5 kDa and a 20 kDa PEG, respectively, yielding two monoconjugates with a mass of ≈50 and ≈45 kDa. Circular dichroism studies showed that both conjugates preserved secondary structures of the protein, and isothermal titration calorimetry experiments demonstrated that their affinity for mAb was approximately 10⁷ M^-1. Upon complexation with a mAb (Trastuzumab or Rituximab), in vitro flow-cytometry analysis of the new ADSs showed high selectivity for the specific antigen expressing cells. In addition, the ADS complex based on Trastuzumab and Protein G, conjugated with a heterobifunctional 20 kDa PEG carrying the toxin Tubulysin A, had a marked cytotoxic effect on the cancer cell line overexpressing the HER2/neu receptor, thus supporting its application in cancer therapy.

Biomedical Imaging: Principles, Technologies, Clinical Aspects, Contrast Agents, Limitations and Future Trends in Nanomedicines

This review article presents the state-of-the-art in the major imaging modalities supplying relevant information on patient health by real-time monitoring to establish an accurate diagnosis and potential treatment plan. We draw a comprehensive comparison between all imagers and ultimately end with our focus on two main types of scanners: X-ray CT and MRI scanners. Numerous types of imaging probes for both imaging techniques are described, as well as reviewing their strengths and limitations, thereby showing the current need for the development of new diagnostic contrast agents (CAs). The role of nanoparticles in the design of CAs is then extensively detailed, reviewed and discussed. We show how nanoparticulate agents should be promising alternatives to molecular ones and how they are already paving new routes in the field of nanomedicine.

Aptamers as quality control tool for production, storage and biosimilarity of the anti-CD20 biopharmaceutical rituximab

Detailed analysis of biopharmaceuticals is crucial for safety, efficacy and stability. Aptamers, which are folded, single-stranded oligonucleotides, can be used as surrogate antibodies to detect subtle conformational changes. We aimed to generate and assess DNA aptamers against the therapeutic anti-CD20 antibody rituximab. Six rituximab-specific aptamers with Kd = 354-887 nM were obtained using the magnetic bead-based systematic evolution of ligands by exponential enrichment (SELEX) technology. Aptamer folds were analysed by online prediction tools and circular dichroism spectroscopy suggesting quadruplex structures for two aptamers while others present B-DNA helices. Aptamer binding and robustness with respect to minor differences in buffer composition or aptamer folding were verified in the enzyme-linked apta-sorbent assay. Five aptamers showed exclusive specificity to the Fab-fragment of rituximab while one aptamer revealed a broader recognition pattern to other monoclonal antibodies. Structural differences upon incubation at 40 °C for 72 h or UV exposure of rituximab were uncovered by four aptamers. High similarity between rituximab originator and biosimilar lots was demonstrated. The most sensitive aptamer (RA2) detected signal changes for all lots of a copy product suggesting conformational differences. For the first time, a panel of rituximab-specific aptamers was generated allowing the assessment of conformational coherence during production, storage, and biosimilarity of different products.

Antibody receptors steal the sweet spotlight

Immunoglobulin G (IgG) antibodies function, in part, through ligation of cell-surface Fc receptors such as FcγRIIIA (also known as CD16A). IgG glycosylation is known to impact antibody function, but the role of FcγRIIIA glycans, if any, is unclear. Patel et al. now reveal that these glycans do impact protein conformation and IgG affinity and display cell-specific glycosylation patterns, leading to a potential model in which the affinity and possibly function of Fc receptors is dictated by the cell type and its surface glycome.

Current and evolving treatment strategies in adult immune thrombocytopenia

Immune thrombocytopenia (ITP) is an acquired autoimmune phenomenon resulting in low platelet count and increased bleeding risk. Goals of upfront management include prompt control of severe bleeding-which is rare-as well as induction and maintenance of a hemostatic platelet count. Thus, optimal management of ITP patients is often challenging and requires a highly individualized approach. Many patients may not suffer significant bleeding despite severe thrombocytopenia and the risk of toxicity associated with treatment may outweigh its benefit. Most patients treated with standard first-line regimen of glucocorticoids achieve an initial response. However, the rate of long-term remission remains low and multiple lines of therapy are often required. Current investigations aim at defining the subgroup of patients at risk of relapse and providing intensified risk-balanced induction regimens to improve long-term disease control. This short review summarizes current and emerging treatment strategies in adult ITP.

The impact of rituximab infusion protocol on the long-term outcome in anti-MuSK myasthenia gravis

Objective

To evaluate whether the clinical benefit and relapse rates in anti‐muscle‐specific kinase (MuSK) myasthenia gravis (MG) differ depending on the protocol of rituximab followed.

Methods

This retrospective multicentre study in patients with MuSK MG compared three rituximab protocols in terms of clinical status, relapse, changes in treatment, and adverse side effects. The primary effectiveness endpoint was clinical relapse requiring a further infusion of rituximab. Survival curves were estimated using Kaplan–Meier methods and survival analyses were undertaken using Cox proportional‐hazards models.

Results

Twenty‐five patients were included: 11 treated with protocol 4 + 2 (375 mg/m²/4 weeks, then monthly for 2 months), five treated with protocol 1 + 1 (two 1 g doses 2 weeks apart), and nine treated with protocol 4 (375 mg/m²/4 weeks). Mean follow‐up was 5.0 years (SD 3.3). Relapse occurred in 18.2%, 80%, and 33.3%, and mean time to relapse was 3.5 (SD 1.5), 1.1 (SD 0.4), and 2.5 (SD 1.4) years, respectively. Based on Kaplan–Meier estimates, patients treated with protocol 4 + 2 had fewer and later relapses than patients treated with the other two protocols (log‐rank test P = 0.0001). Patients treated with protocol 1 + 1 had a higher risk of relapse than patients treated with protocol 4 + 2 (HR 112.8, 95% CI, 5.7–2250.4, P = 0.002). Patients treated with protocol 4 showed a trend to a higher risk of relapse than those treated with protocol 4 + 2 (HR 9.2, 95% CI 0.9–91.8, P = 0.059).

Interpretation

This study provides class IV evidence that the 4 + 2 rituximab protocol has a lower clinical relapse rate and produces a more durable response than the 1 + 1 and 4 protocols in patients with MuSK MG.

Ras and Rap1: A tale of two GTPases

Ras oncoproteins play pivotal roles in both the development and maintenance of many tumor types. Unfortunately, these proteins are difficult to directly target using traditional pharmacological strategies, in part due to their lack of obvious binding pockets or allosteric sites. This obstacle has driven a considerable amount of research into pursuing alternative ways to effectively inhibit Ras, examples of which include inducing mislocalization to prevent Ras maturation and inactivating downstream proteins in Ras-driven signaling pathways. Ras proteins are archetypes of a superfamily of small GTPases that play specific roles in the regulation of many cellular processes, including vesicle trafficking, nuclear transport, cytoskeletal rearrangement, and cell cycle progression. Several other superfamily members have also been linked to the control of normal and cancer cell growth and survival. For example, Rap1 has high sequence similarity to Ras, has overlapping binding partners, and has been demonstrated to both oppose and mimic Ras-driven cancer phenotypes. Rap1 plays an important role in cell adhesion and integrin function in a variety of cell types. Mechanistically, Ras and Rap1 cooperate to initiate and sustain ERK signaling, which is activated in many malignancies and is the target of successful therapeutics. Here we review the role activated Rap1 in ERK signaling and other downstream pathways to promote invasion and cell migration and metastasis in various cancer types.

New horizons for multiple sclerosis therapeutics: milestones in the development of ocrelizumab

Multiple Sclerosis (MS) is an inflammatory and neurodegenerative disease of the central nervous system, and both T and B cells are involved in its pathogenesis. The vast majority of disease-modifying drugs used for MS act on the inflammatory component of the disease and are approved for use in relapsing-remitting (RR) patients. Ocrelizumab (OCR) is the only MS drug that has been approved by the US Food and Drug Administration (FDA) not only for patients with RRMS but also for patients with primary progressive (PP) MS. OCR is a humanized anti-CD20 monoclonal antibody that can deplete the targeted B cells through antibody-dependent cellular cytotoxicity. Treatment involves administration by intravenous infusion every 6 months. OCR can cause long-lasting B-cell depletion and change the pool of reconstituted B cells. Phase III clinical trials have confirmed the results of previous Phase II studies. In particular, OPERA I and II trials, which were performed in patients with RRMS, showed a reduction in the annualized relapse rate, the risk of disability progression, and the number of new/enlarging T2 lesions and enhancing lesions measured using brain magnetic resonance. The ORATORIO trial, performed in PP subjects, showed that OCR can reduce disability progression, improve performance on the timed 25-foot walk, and decrease the total volume of T2 lesions and the mean number of new or enlarging T2 lesions. The most frequent adverse events were the infusion-related reactions and infections. Infections were mostly nasopharyngitis, as well as upper respiratory and urinary tract infections. OCR gives no indication for severe or opportunistic infections. There is not a clear increased risk of malignancies. Nevertheless, it could not be excluded. Real-life registries will provide more information about the long-term safety, the risk of exposure during pregnancy, and the risk of rare adverse events. In this review, we analyze the evidence regarding the efficacy and the safety of OCR.

New Strategies Using Antibody Combinations to Increase Cancer Treatment Effectiveness

Antibodies have proven their high value in antitumor therapy over the last two decades. They are currently being used as the first-choice to treat some of the most frequent metastatic cancers, like HER2⁺ breast cancers or colorectal cancers, currently treated with trastuzumab (Herceptin) and bevacizumab (Avastin), respectively. The impressive therapeutic success of antibodies inhibiting immune checkpoints has extended the use of therapeutic antibodies to previously unanticipated tumor types. These anti-immune checkpoint antibodies allowed the cure of patients devoid of other therapeutic options, through the recovery of the patient’s own immune response against the tumor. In this review, we describe how the antibody-based therapies will evolve, including the use of antibodies in combinations, their main characteristics, advantages, and how they could contribute to significantly increase the chances of success in cancer therapy. Indeed, novel combinations will consist of mixtures of antibodies against either different epitopes of the same molecule or different targets on the same tumor cell; bispecific or multispecific antibodies able of simultaneously binding tumor cells, immune cells or extracellular molecules; immunomodulatory antibodies; antibody-based molecules, including fusion proteins between a ligand or a receptor domain and the IgG Fab or Fc fragments; autologous or heterologous cells; and different formats of vaccines. Through complementary mechanisms of action, these combinations could contribute to elude the current limitations of a single antibody which recognizes only one particular epitope. These combinations may allow the simultaneous attack of the cancer cells by using the help of the own immune cells and exerting wider therapeutic effects, based on a more specific, fast, and robust response, trying to mimic the action of the immune system.

Management of newly diagnosed immune thrombocytopenia: can we change outcomes?

Immune thrombocytopenia resulting from antibody-mediated platelet destruction combined with impaired platelet production is a common cause of thrombocytopenia. The decision to treat newly diagnosed patients is based on several factors including ceasing hemorrhagic manifestations, increasing the platelet count, prevention of bleeding, and inducing remission. Current standard first-line therapy is a course of corticosteroids. Although this treatment paradigm increases the platelet count in the majority of patients, a high percentage relapse after discontinuation of corticosteroid therapy. For this reason, intensification of first-line therapy that results in superior long-term remission rates would be desirable. This manuscript focuses primarily on adults with idiopathic thrombocytopenic purpura (ITP), highlighting pediatric data and practice when applicable. The primary aim is to outline upfront strategies for treatment-naive patients with ITP to enhance remission rates, taking into account assessment of the risks and benefits of these approaches.

Management of newly diagnosed immune thrombocytopenia: can we change outcomes?

Immune thrombocytopenia resulting from antibody-mediated platelet destruction combined with impaired platelet production is a common cause of thrombocytopenia. The decision to treat newly diagnosed patients is based on several factors including ceasing hemorrhagic manifestations, increasing the platelet count, prevention of bleeding, and inducing remission. Current standard first-line therapy is a course of corticosteroids. Although this treatment paradigm increases the platelet count in the majority of patients, a high percentage relapse after discontinuation of corticosteroid therapy. For this reason, intensification of first-line therapy that results in superior long-term remission rates would be desirable. This manuscript focuses primarily on adults with idiopathic thrombocytopenic purpura (ITP), highlighting pediatric data and practice when applicable. The primary aim is to outline upfront strategies for treatment-naive patients with ITP to enhance remission rates, taking into account assessment of the risks and benefits of these approaches.

Modulating inflammation and neuroprotection in multiple sclerosis

Multiple sclerosis (MS) is a neurological disorder of the central nervous system with a presentation and disease course that is largely unpredictable. MS can cause loss of balance, impaired vision or speech, weakness and paralysis, fatigue, depression, and cognitive impairment. Immunomodulation is a major target given the appearance of focal demyelinating lesions in myelin-rich white matter, yet progression and an increasing appreciation for gray matter involvement, even during the earliest phases of the disease, highlights the need to afford neuroprotection and limit neurodegenerative processes that correlate with disability. This review summarizes key aspects of MS pathophysiology and histopathology with a focus on neuroimmune interactions in MS, which may facilitate neurodegeneration through both direct and indirect mechanisms. There is a focus on processes thought to influence disease progression and the role of oxidative stress and mitochondrial dysfunction in MS. The goals and efficacy of current disease-modifying therapies and those in the pipeline are discussed, highlighting recent advances in our understanding of pathways mediating disease progression to identify and translate both immunomodulatory and neuroprotective therapeutics from the bench to the clinic.

Monoclonal Antibodies for Relapsing Multiple Sclerosis: A Review of Recently Marketed and Late-Stage Agents

Treatment of multiple sclerosis (MS) has improved considerably over the last decade because of new insights into MS pathology and biotechnological advances. This has led to the development of new potent pharmaceutical compounds targeting different processes in the complex autoimmune pathology leading to chronic central nervous system (CNS) demyelination, neural loss, and, finally, neurological disability. Although a number of disease-modifying treatments are available for the treatment of the inflammatory phase of MS, there is still a need for highly efficacious therapies with an acceptable safety profile in order to gain therapeutic control early in the disease course. Monoclonal antibodies have proven to be some of the most efficacious disease-modifying therapies in the field of MS, and recent developments in clinical research hold promise for new compounds fulfilling the need for improved safety and high efficacy. We review recent developments in the field of therapeutic monoclonal antibodies used for the treatment of MS and current information on the mode of action, efficacy, and safety of existing and emerging therapeutic monoclonal antibodies as well as their place within the context of different treatment strategies. Finally, we consider the most important future developments.

Autoantibodies: Opportunities for Early Cancer Detection

Cancer cells can induce an immunological response resulting in the production of tumor-associated (TA) autoantibodies. These serum immunobiomarkers have been detected for a range of cancers at an early stage before the development of clinical symptoms. Their measurement is minimally invasive and cost effective using established technologies. TA autoantibodies are present in a clinically significant number of individuals and could supplement current screening modalities to aid early diagnosis of high-risk populations and assist the clinical management of patients. Here we review their production, discovery, and validation as biomarkers for cancer and their current and future potential as clinical tools.

Necrotizing fasciitis following rituximab therapy

Rituximab has considerably modified thetherapeutic strategy for B-cell lymphoproliferative malignancies, most notably non-Hodgkin’s lymphoma (NHL). Rituximab, alone or in combination with chemo-therapy, is being used to treat NHL with limited toxicity. We report two cases, one fatal, of necrotizing fasciitis following the use of rituximab in patients with NHL. No obvious predisposing factors were noted in either case. Practitioners need to beaware of this rare side effect and take prompt and aggressive action at the first onset of symptoms.

Development and Characterization of a New Antipeptide Monoclonal Antibody Directed to Human CD20 Antigen

The rapid expansion of immunotherapeutic approaches for treatment of various diseases, including cancers, has been greatly facilitated by the invention of new generation of antibodies. Clinical studies have indicated that anti-CD20 mAb-based therapies represent an effective treatment for various diseases with overexpression of CD20 on their cell surface, such as non-Hodgkin's lymphoma, hemolytic anemia, as well as autoimmune diseases like rheumatoid arthritis. Technically, due to a short extra membrane domain, the recombinant CD20 protein is a difficult antigen to raise immune responses. In search for new monoclonal antibodies, the authors used an antigenic polypeptide, which yielded numbers of new binders that may lead to production of anti-CD20 antibodies, with improved diagnostic or clinical attributes. Mice were immunized with extra membrane loop of human CD20 (exCD20) polypeptide. The exCD20 antigen showed a desired immune response and was able to develop a monoclonal antibody, 3B4C10, which reacted well with peptide antigen as well as native antigen on the surface of Raji B-cell line. The antibody 3B4C10 with a balanced K(on) and K(off) may be applicable in the construction of affinity columns or beads for isolation and purification of CD20-positive cells and cancer stem cells.

The common marmoset as an indispensable animal model for immunotherapy development in multiple sclerosis

New drugs often fail in the translation from the rodent experimental autoimmune encephalomyelitis (EAE) model to human multiple sclerosis (MS). Here, we present the marmoset EAE model as an indispensable model for translational research into MS. The genetic heterogeneity of this species and lifelong exposure to chronic latent infections and environmental pathogens create a human-like immune system. Unique to this model is the presence of the pathological hallmark of progressive MS, in particular cortical grey matter lesions. Another great possibility of this model is systemic and longitudinal immune profiling, whereas in humans and mice immune profiling is usually performed in a single compartment (i.e. blood or spleen, respectively). Overall, the marmoset model provides unique opportunities for systemic drug-effect profiling.

The potential role for ocrelizumab in the treatment of multiple sclerosis: current evidence and future prospects

B cells play a central role in the pathogenesis in multiple sclerosis (MS), being involved in the activation of proinflammatory T cells, secretion of proinflammatory cytokines, and production of autoantibodies directed against myelin. Hence, the usage of B-cell-depleting monoclonal antibodies as therapy for autoimmune diseases including MS lay near at hand. Rituximab was the first therapeutic B-cell-depleting chimeric monoclonal antibody to be used successfully in MS. Ocrelizumab, a second-generation humanized anti-CD20 antibody, was explored in a large phase II, randomized, placebo-controlled multicentre trial in patients with relapsing-remitting disease. Compared with placebo, two doses of ocrelizumab (600 and 2000 mg on days 1 and 15) showed a pronounced effect on disease activity seen in magnetic resonance imaging (MRI) as gadolinium-enhanced lesions (89% and 96% relative reduction, both p < 0.001) and also had a significant effect on relapses. In exploratory analyses, both doses of ocrelizumab had better effect on gadolinium-enhanced lesions than interferon beta-1a intramuscularly that was used as a reference arm. Adverse effects were mainly infusion-related reactions, in particular during the first infusion. Serious infections occurred at similar rates in ocrelizumab and placebo-treated patients, and no opportunistic infections were reported. However, progressive multifocal leukoencephalopathy (PML) has been reported in patients treated with anti-CD20 monoclonal antibodies for other indications. Other anti-CD20 monoclonal antibodies have been tested as treatments for MS, including ofatumumab that has shown beneficial results in placebo-controlled phase II trials in patients with relapsing-remitting MS. Ocrelizumab is now in phase III development for the treatment of relapsing-remitting MS, as well as primary progressive MS, and the results of ongoing clinical trials are eagerly awaited and will determine the place of ocrelizumab in the armamentarium of MS therapies.

The effects of intrathecal rituximab on biomarkers in multiple sclerosis

OBJECTIVES

Clinical trials of IV-rituximab have proved successful. It is unclear whether intrathecal (IT)-rituximab is more efficacious at lower doses. We examine its effects on B-cell biomarkers.

METHODS

MS patients received IT-rituximab at 3 time-points. CSF and serum samples were obtained at up to 5 time-points (days 0, 7, 14, 56 and 112). Serum and CSF BAFF and CXCL13, and CSF kappa and lambda free light chains (FLC) were measured. Flow cytometry was performed, examining effects on lymphocytes, CD3-19+ and CD3-20+ cells.

RESULTS

CSF BAFF fell following rituximab (p=0.0091 absolute values, p=0.0284 change from baseline) whilst serum BAFF increased across time-points 1-4 (p=0.0005 absolute values, p=0.0017 change from baseline). There were significant reductions in CD20+ and CD19+ cells in blood from baseline (p<0.0001) but not in CSF. CSF kappa FLC levels significantly increased (p=0.0480).

CONCLUSIONS

BAFF levels fall in CSF but increase in serum following IT-rituximab. Rituximab appears to act peripherally with dramatic decreases in peripheral CD20+ and CD19+ cells. It is likely that CSF B-cell counts were too low to enable differences to be seen. The rapid reduction in B-cells suggests rituximab has immediate effects. The profound depletion of B-cells, despite low doses of rituximab, underlines rituximab's efficacy.

Versatile microscale screening platform for improving recombinant protein productivity in Chinese hamster ovary cells

Chinese hamster ovary (CHO) cells are widely used as cell factories for the production of biopharmaceuticals. In contrast to the highly optimized production processes for monoclonal antibody (mAb)-based biopharmaceuticals, improving productivity of non-mAb therapeutic glycoproteins is more likely to reduce production costs significantly. The aim of this study was to establish a versatile target gene screening platform for improving productivity for primarily non-mAb glycoproteins with complete interchangeability of model proteins and target genes using transient expression. The platform consists of four techniques compatible with 96-well microplates: lipid-based transient transfection, cell cultivation in microplates, cell counting and antibody-independent product titer determination based on split-GFP complementation. We were able to demonstrate growth profiles and volumetric productivity of CHO cells in 96-half-deepwell microplates comparable with those obtained in shake flasks. In addition, we demonstrate that split-GFP complementation can be used to accurately measure relative titers of therapeutic glycoproteins. Using this platform, we were able to detect target gene-specific increase in titer and specific productivity of two non-mAb glycoproteins. In conclusion, the platform provides a novel miniaturized and parallelisable solution for screening target genes and holds the potential to unravel genes that can enhance the secretory capacity of CHO cells.

Fc Gamma Receptor 3A and 2A Polymorphisms Do Not Predict Response to Rituximab in Follicular Lymphoma

PURPOSE

Preclinical studies suggest that SNPs in the Fc gamma receptor (FCGR) genes influence response to rituximab, but the clinical relevance of this is uncertain.

EXPERIMENTAL DESIGN

We prospectively obtained specimens for genotyping in the rituximab extended schedule or re-treatment trial (RESORT) study, in which 408 previously untreated, low tumor burden follicular lymphoma (FL) patients were treated with single agent rituximab. Patients received rituximab in 4 weekly doses and responders were randomized to rituximab re-treatment (RR) upon progression versus maintenance rituximab (MR). SNP genotyping was performed in 321 consenting patients.

RESULTS

Response rates to initial therapy and response duration were correlated with the FCGR3A SNP at position 158 (rs396991) and the FCGR2A SNP at position 131 (rs1801274). The response rate to initial rituximab was 71%. No FCGR genotypes or grouping of genotypes were predictive of initial response. A total of 289 patients were randomized to RR (n = 143) or to MR (n = 146). With a median follow-up of 5.5 years, the 3-year response duration in the RR arm and the MR arm was 50% and 78%, respectively. Genotyping was available in 235 of 289 randomized patients. In patients receiving RR (n = 115) or MR (n = 120), response duration was not associated with any FCGR genotypes or genotype combinations.

CONCLUSIONS

Based on this analysis of treatment-naïve, low tumor burden FL, we conclude that the FCGR3A and FCGR2A SNPs do not confer differential responsiveness to rituximab.

Targeted Therapies in Adult B-Cell Malignancies

B-lymphocytes are programmed for the production of immunoglobulin (Ig) after antigen presentation, in the context of T-lymphocyte control within lymphoid organs. During this differentiation/activation process, B-lymphocytes exhibit different restricted or common surface markers, activation of cellular pathways that regulate cell cycle, metabolism, proteasome activity, and protein synthesis. All molecules involved in these different cellular mechanisms are potent therapeutic targets. Nowadays, due to the progress of the biology, more and more targeted drugs are identified, a situation that is correlated with an extended field of the targeted therapy. The full knowledge of the cellular machinery and cell-cell communication allows making the best choice to treat patients, in the context of personalized medicine. Also, focus should not be restricted to the immediate effects observed as clinical endpoints, that is, response rate, survival markers with conventional statistical methods, but it should consider the prediction of different clinical consequences due to other collateral drug targets, based on new methodologies. This means that new reflection and new bioclinical follow-up have to be monitored, particularly with the new drugs used with success in B-cell malignancies. This review discussed the principal aspects of such evident bioclinical progress.

Rituximab: modes of action, remaining dispute and future perspective

Less than two decades ago, immunotherapy joined chemotherapy and radiotherapy as an effective approach for the treatment of cancer. The anti-CD20 monoclonal antibody, rituximab, is now used to treat almost all types of non-Hodgkin's B-cell lymphomas, and it could be useful in the treatment of other diseases with B-cell involvement. Upon binding, rituximab induces death of the target cells. It seems to act not only by activating immune system defense mechanisms such as complement-dependent and antibody-dependent cellular cytotoxicity, but also by inducing direct cell death. In this paper, we review current knowledge on rituximab mechanisms of action, with particular attention to its direct effects, and also highlight potential future avenues of research.

A novel placental like alkaline phosphatase promoter driven transcriptional silencing combined with single chain variable fragment antibody based virosomal delivery for neoplastic cell targeting [corrected]

BACKGROUND

Placental like alkaline phosphatase (PLAP), an oncofetal antigen, is highly expressed in germ cell, cervical, ovarian and several other tumour types but minimally in normal tissues [corrected]. The expression of a PLAP promoter based transcriptional unit following antigen mediated cell specific delivery is a possible approach for tumour targeting.

METHODS

PLAP promoter alone or in combination with NFκB DNA response elements was used for expressing shRNA targeting the long control region (LCR) of human papillomavirus (HPV)-16 oncogenes E6 and E7 via transcriptional gene silencing in PLAP expressing cervical cancer cell lines, SiHa and CaSki. This was packaged in a Sendai virus envelope incorporating a single chain variable fragment antibody (scFv) for antibody mediated targeting. Specificity and efficacy of the shRNA was assessed by studying the heterochromatization, down regulation of the HPV-16 E6/E7 genes and subsequent effects on their targets and cell growth properties.

RESULTS

Reduction of HPV-16 E6 and E7 expression by TGS led to the activation of the previously suppressed target genes of p53 (PUMA and NOXA) and Rb (cyclins A2 and E). Cell death was seen only in PLAP expressing HPV-16 infected SiHa and CaSki cells but not in the HPV-18 integrated HeLa and non-PLAP CHO cells. There was reduction in the enhancer associated transcripts of the long control region (LCR) of HPV-16 E6/E7 genes. Also, an increase in the enrichment of dimethylated histone three lysine nine (H3K9Me2) and trimethylated histone three lysine twenty-seven (H3K27Me3) was observed by ChIP assay, which decreased upon trichostatin A treatment, indicating a possible mechanism for the heterochromatization of the target LCR region.

CONCLUSION

A combination of novel PLAP promoter and antibody based specificities has the potential for being developed as a possible therapeutic strategy for PLAP positive neoplasia.

Complement in therapy and disease: Regulating the complement system with antibody-based therapeutics

Complement is recognized as a key player in a wide range of normal as well as disease-related immune, developmental and homeostatic processes. Knowledge of complement components, structures, interactions, and cross-talk with other biological systems continues to grow and this leads to novel treatments for cancer, infectious, autoimmune- or age-related diseases as well as for preventing transplantation rejection. Antibodies are superbly suited to be developed into therapeutics with appropriate complement stimulatory or inhibitory activity. Here we review the design, development and future of antibody-based drugs that enhance or dampen the complement system.

Retinoic acid enhances the levels of IL-10 in TLR-stimulated B cells from patients with relapsing-remitting multiple sclerosis

We have explored the beneficial effects of retinoic acid (RA) on B cells from multiple sclerosis (MS) patients. When co-stimulated via the toll-like receptors (TLRs) TLR9 and RP105, MS B cells secreted less of the anti-inflammatory cytokine interleukin 10 (IL-10) compared to B cells from healthy controls. Importantly, RA enhanced the secretion of IL-10 by MS-derived B cells without affecting the levels of the pro-inflammatory cytokine TNF-α. RA revealed the same ability to induce IL-10 as did interferon-β-1b (IFN-β-1b), and B-cells from patients treated with glatiramer acetate or IFN-β-1b still displayed the beneficial effects of RA on the IL-10/TNF-α ratio.

Functions of Antibodies

Antibodies can impact pathogens in the presence or in the absence of effector cells or effector molecules such as complement, and experiments can often sort out with precision the mechanisms by which an antibody inhibits a pathogen in vitro . In addition, in vivo models, particularly those engineered to knock in or knock out effector cells or effector molecules, are excellent tools for understanding antibody functions. However, it is highly likely that multiple antibody functions occur simultaneously or sequentially in the presence of an infecting organism in vivo . The most critical incentive for measuring antibody functions is to provide a basis for vaccine development and for the development of therapeutic antibodies. In this respect, some functions, such as virus neutralization, serve to inhibit the acquisition of a pathogen or limit its pathogenesis. However, antibodies can also enhance replication or contribute to pathogenesis. This review emphasizes those antibody functions that are potentially beneficial to the host. In addition, this review will focus on the effects of antibodies on organisms themselves, rather than on the toxins the organisms may produce.

Conjugation of a reactive thiol at the nucleotide binding site for site-specific antibody functionalization

Described here is a UV photo-cross-linking method that utilizes the NBS (nucleotide binding site) for site-specific covalent functionalization of antibodies with reactive thiol moieties (UV-NBS(Thiol)), while preserving antibody activity. By synthesizing an indole-3-butyric acid (IBA) conjugated version of cysteine we site-specifically photo-cross-linked a reactive thiol moiety to antibodies at the NBS. This thiol moiety can then be used as an orthogonally reactive location to conjugate various types of functional ligands that possess a thiol reactive group through disulfide bond formation or reaction with a maleimide functionalized ligand. Our results demonstrate the utility of the UV-NBS(Thiol) method by successfully functionalizing a prostate specific antigen antibody (IgG(PSA)) with IBA-Thiol and subsequent reaction with maleimide-fluorescein. An optimal UV energy of 0.5-1.5 J/cm(2) was determined to yield the most efficient photo-cross-linking and resulted in 1-1.5 conjugations per antibody while preserving antibody/antigen binding activity and Fc recognition. Utilizing the IBA-Thiol ligand allows for an efficient means of site-specifically conjugating UV sensitive functionalities to antibody NBS that would otherwise not have been amenable by the previously described UV-NBS photo-cross-linking method. The UV-NBS(Thiol) conjugation strategy can be utilized in various diagnostic and therapeutic applications with nearly limitless potential for the preparation of site-specific covalent conjugation of affinity tags, fluorescent molecules, peptides, and chemotherapeutics to antibodies.