With advanced research to meet the recent medical and medicine demands, researchers have come up with an improvement to the first-generation antibody used for treatment. With antibody therapy, the body will fight diseases and infections that surface in the cell. For patients who are experiencing thrombocytopenia and are in ICU, pf4 antibody are applied to treat their platelet. 

The second-generation antibody used for therapy is laboratory-made antibodies meant to diagnose and treat checkpoint inhibitors. This antibody has been proven to be more effective than the previously researched first generation, which entails epoetins, somatotropins, bone marrow stimulating factors.

Second Generation Antibody

Second-generation antibodies are monoclonal antibodies or proteins that are generated through the process of fusing antibody and receptor moieties. Second-generation biosimilars have greater structural and molecular complexity. The second generation antibodies are of two forms with their different biological actions. The first antibody of the second generation is the Alemtuzumab which binds to CD52 on lymphocytes that are matured. 

It depletes the circulation of T cells and B cells which are repopulated instinctively. The process involved in Alemtuzumab can result in lasting changes in adaptive immunity. Daclizumab, the other part of the second generation antibody, targets CD25. And this is the α-subunit of the high-affinity IL-2 receptor. Using Daclizumab for diagnosis or treatment reduces the IL-2 signaling through the receptor. It then increases the signaling at the intermediate affinity IL-2 receptor. With this,  the numbers of CD56 natural killer cells increase, which decreases the numbers of lymphoid tissue inducers, resulting in reduced immune responses. 

Immune pathologies have also been discovered to suppress interleukin-2 (IL-2) through the preferential expansion of regulatory T cells. IL-2 is key to T cells homeostasis, more importantly to CD4+ T regulatory cells and memory CD8+ cells. The vigorous proliferation of the cells indicates this in vivo after the injections of superagonist IL-2 and anti IL2 antibody complexes.

What are checkpoint inhibitors 

Checkpoint inhibitors are types of immunotherapy and a monoclonal antibody or targeted treatment responsible for blocking proteins that obstructs the immune system from attacking the cancer cells. They are cancer treatments such as melanoma, skin cancer, and lungs cancer. Drugs that block checkpoint protein are all regarded as checkpoint inhibitors, and they include pembrolizumab (Keytruda), ipilimumab (Yervoy), nivolumab (Opdivo), and atezolizumab (Tecentriq).

How checkpoint inhibitors functions

The body’s immune system protects from contracting diseases, killing bacteria and viruses. The immune cell that protects the body is the T cell. Proteins are contained on the T cells, which turn on immune response, and other proteins that turn it off. These proteins on the T cells are known as the checkpoint proteins. When there is an infection, some checkpoint proteins will alert the T cells to be active. However, prolonged activeness of T cells or responding to things they ought not to can destroy healthy cells and tissues. As a result, some other checkpoints dictate that the T cells switch off to avoid damage to the healthy cells.

Some cells that have been infected with cancer produce high levels of proteins. And when this occurs, it will make the T cells to be turned off when they should be attacking the cancer cells. As a result, the cancer cells are making the immune system stop, making it difficult for T cells to recognize the cancer cells to kill them. 

So, the drugs that block the checkpoint protein are called checkpoint inhibitors. The function of these drugs is to hinder the proteins on the cancer cells from stopping. The immune system becomes active, and the T cells can now locate the cancer cells and fight them. The CCR2 antibody, a 42KD G protein-coupled receptor, is used for bone marrow homeostasis and expressed in various tissues like blood, brain, heart, kidney, liver, pancreas, ovary, spinal cord, etc. 

Types of checkpoint proteins 

There are different checkpoint proteins, and various drugs can be introduced. Some of the checkpoint proteins are:

  1. CTLA-4 (cytotoxic T lymphocyte-associated protein 4)
  2. PD-1 (programmed cell death protein 1)
  3. PD-L1 (programmed cell death ligand 1)
  1. CTLA-4  (cytotoxic T lymphocyte-associated protein 4): this checkpoint protein is found on the T cells. Ipilimumab (Yervoy), a checkpoint inhibitor, blocks the CTLA-4 on the T cells. This is a treatment for critical melanoma and renal cell cancer.
  2. PD-1: for PD-1, which is also found on T cells, the checkpoint inhibitors for blocking it are nivolumab (opdivo) and pembrolizumab (Keytruda). These drugs are used to treat people with melanoma skin cancer, Hodgkin lymphoma, and non-small cell lung cancer. Each of these drugs can also be used for other types of cancer. For instance, nivolumab is also used to treat kidney, head, and neck cancers, while pembrolizumab can further treat urinary tract cancers.
  3. PD-L1: this is found on the cancer cells, and the checkpoint inhibitors that block it are atezolizumab, Avelumab, and durvalumab. Atezolizumab acts on lung cancer, liver cancer, breast cancer, and urothelial cancer. Avelumab is meant to treat a specific skin cancer known as Merkel cell carcinoma (MCC) and urinary tract cancers. Durvalumab is for the treatment of non-small cell lung cancer.