Metastatic colorectal cancer can now be treated with the help of monoclonal antibodies. Cetuximab and Panitumumab are examples of appropriate medicines. Point of application of drugs is always the epidermal growth factor receptor (EGFR). Clinical trials for monotherapy hereby show response rates of around 10%.
Unfortunately, the positive detection of EGFR expression by immuno-staining is not reliable. For the preservation of clinical results must therefore be an intensive search for alternative, more predictive biomarkers. The oncogenic activation of the EGFR signaling pathways, such as the mutation of the KRAS, BRAF or PIK3CA oncogenes, or the inactivation of the PTEN tumor suppressor gene is of paramount importance for the progression of colorectal carcinomas. KRAS mutations occur in 35-45% of patients with colorectal carcinoma and appears as an important predictive marker of resistance to panitumumab or cetuximab treatment. Wild-type KRAS-carrying colorectal tumors showing mutation of BRAF or PIK3CA or loss of PTEN expression may be associated with resistance to EGFR-targeted monoclonal antibody treatment. These additional biomarkers require further validation before including them into clinical practice. But the development of new treatment  algorithms to identify patients who are most likely to respond to treatment will be allowed by further information of the molecular basis for sensitivity or resistance to EGFR-targeted monoclonal antibodies. Individualized treatment for patients with metastatic colorectal cancer will be more realizable by the use of biomarkers like KRAS mutations for anti-EFGR monoclonal antibody treatment.

Interferon beta (IFNβ) is used in the treatment of multiple sclerosis (MS). It can reduce the relapse rate and the lesion formation of MRI and slow the progression of the disease. However, some patients develop neutralizing antibodies (NAbs) against interferon beta durin chronic administration of IFNβ. This has been observed in other protein-based drugs in long-term studies as well. Up to 25% of patients treated 3-times-weekly subcutaneously with IFNβ-1a develop Nabs. This could be observed for 2% of the once-weekly treated patients with IFNβ-1a intramuscular. The published data from clinical studies show that the efficacy in patients with NAb-positive compared with those who are NAb negative is reduced. Neutralizing antibodies can potentially cross the blood-brain barrier in IFN-beta-treated patients resulting in relapsing-remitting multiple sclerosis (RRMS) and affect the endogenous IFNβ function within the central nervous system (CNS).  This is confirmed by results of a study by Shapiro et al. It was demonstrated that high serum titers of NAbs (1865-19,320 tenfold reduction units ) in human astrocytes (in culture) inhibit toll-like receptor-3 ligand and endogenous IFNβ-mediated production of CXCL10 and IL-6. The case study shows that patients with positive titers of NAbs and BAbs in serum did not have detectable NAbs and BAbs that could be detected in the CSF. The absence of these antibodies in the cerebrospinal fluid does not eliminate in general that antibodies may cross the blood-brain barrier locally in the area of inflammation yet nor reach detectable levels in the CSF.

The transport and the activity of many regulatory proteins is modulated by bound heparan sulfate (HS). HS ‘phage display antibodies are powerful tools for the analysis of the native HS structures in situ, but their epitopes are currently not well defined. The analysis of the measures related to access to a number of HS-specific antibodies by competitive binding assays with defined, chemically modified heparins reveals that O-sulfates are necessary for binding, an increase in sulfation is not necessarily correlated with an increase in antibody reactivity. The binding assays and immunohistochemistry showed that some antibodies can recognize different epitopes. Not simple linear sequences, but families of structurally similar motifs based on the minimal variation of sulfation and conformation influence the affinity of the interaction. The modeling of the antibody on the computer shows that they possess strong basic CDR3 regions, which define the number of possible orientations of the HS bond. Contrary to expectations, significant differences between the presence of epitopes in tissue samples that show was that the in vitro – specificity does not necessarily correlate with the specificity of in situ / vivo. The epitopes are therefore more complex than previously thought. Overall, these data points are important for structure-activity relationships of HS.

Display technologies have evolved from the outset and have now proved to be very useful when it comes to the task of selecting specific antibodies. Most of the selected antibodies via these platforms still need to be modified for their use in humans. At the same time they are restricted in their antigen recognition. These platforms are not well suited for in vivo selections. A novel cell-based antibody display platform is designed to help now. The validation of antibodies on the surface of T lymphocytes that can be used as part of a chimeric-immune receptor (CIR) mediating signaling ideal index the antigen-antibody interaction to show a demonstrable change in the T-cell phenotype. With this method an in vitro selection with a lentiviral-transduced human T-cell line worked successfully. A tumor-specific CIR on the surface of the cell was verified as an expression of carcino embryonic antigen. Based on effective interaction between the CIR and the tumor antigen, it was shown that the combination of CIR-mediated activation by FACS sorting of CD69 + T cells, it is possible to isolate the tumor by indication for a specific cell surface antigen. There was an accumulation of at least 103-fold after two passes, which led to a homogeneous population of T cells, which led to tumor-specific CIRS.

The Helicobacter pylori infection is one of the most common bacterial infections in humans. Nearly 50% of the world´s population is infected. The incidence of H. pylori is correlated with the development of gastritis, peptic ulcer, gastric cancer and MALT lymphoma. The infection is usually acquired in childhood and is compatible with the socio-demographic factors such as low socioeconomic status, poor hygiene and other effects associated. In children, the diagnosis is often difficult. Symptoms such as abdominal pain, diarrhea, vomiting are nonspecific. Children often develop a serological response immunization against low-molecular-weight antigens.
Currently there are several invasive and non-invasive diagnostic tests for the detection of H. pylori infection at children. The invasive investigation methods are based mainly on the identification of H. pylori in culture, histological examination and urease rapid tests (RUT). Non-invasive tests include the detection of bacterial urease using the urea breath test (UBT), antibody-based detection in various media and other methods.
Antibody-based tests have been developed during the recent decades. These tests differ in their functions. The main advantages of antibody-based tests are their simplicity, low cost, speed and minimal burden on patients. Any proposed tests using antibody-based detection include enzyme-linked immunosorbent assay (ELISA) and Western blot (WB) technique. The ELISA has the advantage that many serum samples can be tested in parallel and the process can be fully automated.