CAR T Cell Therapy

 

Chimeric antigen receptors (CARs), (also known as Chimeric immunoreceptors, Chimeric T cell receptors, Artificial T cell receptors) are engineered receptors, which graft an arbitrary specificity onto an immune effector cell (T cell). Typically, these receptors are used to graft the specificity of a monoclonal antibody onto a T cell; with transfer of their coding sequence facilitated by retroviral vectors. The receptors are called chimeric because they are composed of parts from different sources.

 

CARs are under investigation as a therapy for cancer, using a technique called adoptive cell transfer. T cells are removed from a patient and modified so that they express receptors specific to the patient's particular cancer. The T cells, which can then recognize and kill the cancer cells, are reintroduced into the patient. 

 

Checkpoint Inhibitors

 

Immune checkpoints affect immune system functioning. Immune checkpoints can be stimulatory or inhibitory. Tumors can use these checkpoints to protect themselves from immune system attacks. Checkpoint therapy can block inhibitory checkpoints, restoring immune system function. One ligand-receptor interaction under investigation is the interaction between the transmembrane programmed cell death 1 protein (PDCD1, PD-1; also known as CD279) and its ligand, PD-1 ligand 1 (PD-L1, CD274). PD-L1 on the cell surface binds to PD1 on an immune cell surface, which inhibits immune cell activity. Among PD-L1 functions is a key regulatory role on T cell activities. It appears that (cancer-mediated) upregulation of PD-L1 on the cell surface may inhibit T cells that might otherwise attack. Antibodies that bind to either PD-1 or PD-L1 and therefore block the interaction may allow the T-cells to attack the tumor.

 

 

Oncolytic Virology

 

An oncolytic virus is a virus that preferentially infects and kills cancer cells. As the infected cancer cells are destroyed by oncolysis, they release new infectious virus particles or virions to help destroy the remaining tumour. Oncolytic viruses are thought not only to cause direct destruction of the tumour cells, but also to stimulate host anti-tumour immune responses.

 

The potential of viruses as anti-cancer agents was first realised in the early twentieth century, although coordinated research efforts did not begin until the 1960s. A number of viruses including adenovirus, reovirus, measles, herpes simplex, Newcastle disease virus and vaccinia have now been clinically tested as oncolytic agents. Most current oncolytic viruses are engineered for tumour selectivity, although there are naturally occurring examples such as reovirus and the senecavirus, resulting in clinical trials.

 

HIV Immunology

 

The HIV virus is commonly transmitted via unprotected sexual activity, blood transfusions, hypodermic needles, and from mother to child. Upon acquisition of the virus, the virus replicates inside and kills T helper cells, which are required for almost all adaptive immune responses.

 

After the virus enters the body there is a period of rapid viral replication, leading to an abundance of virus in the peripheral blood. During primary infection, the level of HIV may reach several million virus particles per milliliter of blood.

 

This response is accompanied by a marked drop in the numbers of circulating CD4+ T cells. This acute viremia is associated in virtually all people with the activation of CD8+ T cells, which kill HIV-infected cells, and subsequently with antibody production, or seroconversion. The CD8+ T cell response is thought to be important in controlling virus levels, which peak and then decline, as the CD4+ T cell counts rebound. A good CD8+ T cell response has been linked to slower disease progression and a better prognosis, though it does not eliminate the virus.

 

Algal Biofuels

 

Algae fuel or algal biofuel is an alternative to liquid fossil fuels that uses algae as its source of energy-rich oils. Also, algae fuels are an alternative to common known biofuel sources, such as corn and sugarcane. Several companies and government agencies are funding efforts to reduce capital and operating costs and make algae fuel production commercially viable. Like fossil fuel, algae fuel releases CO2 when burnt, but unlike fossil fuel, algae fuel and other biofuels only release CO2 recently removed from the atmosphere via photosynthesis as the algae or plant grew.

 

Algae biodiesel is still a fairly new technology. Despite the fact that research began over 30 years ago, it was put on hold during the mid-1990s, mainly due to a lack of funding and a relatively low petroleum cost. For the next few years algae biofuels saw little attention; it was not until the gas peak of the early 2000s that it eventually had a revitalization in the search for alternative fuel sources. While the technology exists to harvest and convert algae into a usable source of biodiesel, it still hasn't been implemented into a large enough scale to support the current energy needs.