There is a new class of drugs known as checkpoint inhibitors that have revolutionized the options to treat many diseases, including cancers that were previously thought to be untreatable. Many of these drugs have been in the news as well-known patients, like former President Jimmy Carter, have received a checkpoint inhibitor to treat his metastatic melanoma. What is the mechanism of these novel drugs?
The body’s immune system contains several proteins known as checkpoints. As their name suggests, they regulate the activation or suppression of critical steps or checkpoints of the immune system. PD-1 is a key protein present on some immune cells. With normal cells, PD-1 will recognize another cell’s protein known as PD-L1 and allow it to survive. Cancer cells produce an aberrant PD-L1 molecule that fools the body’s immune cells into recognizing the cancer cells as normal. This defect in the checkpoint mechanism allows the cancer cells to bypass and elude the usual pathways by which the immune system may eliminate these and other foreign cells.
By synthesizing drugs that can inhibit or block these abnormal PD-L1 proteins on cancer cells, these drugs allow the body’s native immune system to effectively eliminate these cancer cells, overcoming their resistance. Thus, an entirely new class of drugs, the checkpoint inhibitors, has emerged.
Cancer cells are remarkable in their ability to camouflage their lethal identities and mimic normal cells, eluding the body’s usual immune system defenses. This sounds suspiciously like sin in our lives. Sin masquerades as good or noble behavior but in reality, is feeding our pride and ego and guiding us on a path to self-destruction. Is there a way to reverse the effects of sin? Is there a checkpoint inhibitor for the sin that ravages our lives?
As it is, I rejoice, not because you were grieved, but because you were grieved into repenting. For you felt a godly grief, so that you suffered no loss through us. For godly grief produces a repentance that leads to salvation without regret, whereas worldly grief produces death.
2 Corinthians 7:9-10 (ESV)
The Holy Spirit indwells within every believer in Jesus Christ and He helps us to recognize the sins in our life that we may be unwilling to recognize. One’s sin of pride may be camouflaged under noble pursuits of charitable work, seeking accolades for our activities rather than focusing upon helping others. The sin of greed may be sublimated under a dubious tax deduction.
How can we be assured that it is truly a sin that we are confessing and repenting? When He convicts us of sin in our lives, we have the assurance that when we truly repent, it will be godly grief that leads to salvation and peace with God. The Holy Spirit is the Absolute checkpoint inhibitor who leads us to salvation through faith and belief in Jesus Christ.
Love and trust the Lord; seek His will in your life.