HIV and the Complement System

HIVand the Complement System


HIVand the complement system

Functionof HIV Protease, Integrase, and Reverse Transcriptase

Atkinson&amp Frank (2006) contend that the HIVIntegrase is an enzyme generated by HIV, which enables its geneticmaterial to be incorporated into the DNA or gene of the diseased orinfected human cell. The main function of Integrase is to slot in theHIV DNA into the human chromosomal DNA, a step very critical for HIVreplication. After integration, the infected cell now becomes apermanent carrier of HIV genome (WHO &amp UNICEF, 2010). On theother hand, HIV Protease is essential for the life cycle of thevirus. In fact, Atkinson&amp Frank (2006) assert that whenthe HIV RNA is translated into a polypeptide series, the series isgathered in a long chain that is made up of several individualproteins (reverse transcriptase, protease and integrase). Before allthese enzymes become functional, protease must cut the long chaininto single enzyme components, which then makes it possible for theproduction of new viruses. With the absence of effective HIVprotease, the HIV remains harmless to the human cell.

AReverse transcriptase (RT) can be described as an enzyme, which isused in spawning matching DNA, mainly known as complementary DNA(cDNA). According to Perez,Fernandes, &amp Ramos (2010) and WHO&amp UNICEF (2010), to infect the human body the HIV virus uses aReverse transcriptase. The HIV uses the enzyme to create a singlestranded DNA from RNA, the process referred to as reversetranscriptase. After reverse transcribing the RNA genome, thegenerated single stranded DNA is then incorporated into the humangenome and duplicated along with it. Without this enzyme, the viralgenome cannot manage to integrate into the human cell, which wouldresult in failure to replicate.

Characteristicsof HIV, which accounts for the transmission

Accordingto Isaacman-Beck&nbspet al. (2009) and Perez (2010), HIV has severalproperties, which may relate to the pathogenesis of AIDS. HIV hasfive additional nonstructural genes including a tatmaster switch,which enable it to control its replication, delete, insert andreplicate nucleotides in order to avoid immune responses. HIV genomesare highly lymphotropic and can attack the helperlymphocytes,and other cells since the envelopeglycoproteinsof these cells interrelate with definite CD4 superficial receptors.Isaacman-Becket al. (2009) maintain thatresearchers point out that, epidemiologically, HIV/AIDS istransmitted and distributed in USA and Europe, almost exclusively inall populations engaging in behavioral activities that carry highrisks of genital and systemic infections. Mainly, sexual intercourseremains the largest mode of transmission of HIV i.e. all form ofsexual intercourse, anal, oral and normal. HIV can also betransferred to another person through sharing of needles, syringes orother injections with someone infected especially among groupsaddicted to drug use. HIV can also be transmitted to a child from themother, if the necessary precautions and procedures are not followedduring pregnancy period and during delivery. HIV transmissions canalso occur in health care settings where health professionals mayaccidently or carelessly are infected while handling infectedpatients. HIV is also transmitted via donated blood, but this is rarein many countries where thorough blood screening is done before beingused in hospitals.

Functionof B-lymphocytes, killer lymphocytes, helper T-lymphocytes andmacrophages in the immune system and how HIV affects this system

Themain function of B-lymphocytes is to form antibodies, which areessential in fighting certain types of bacterial and fungalinfections. When a B lymphocyte is exposed to an antigen, it isstimulated to start in a memory B cell responsible for releasingantibodies or the plasmacell.Killer lymphocytes (cytotoxic) T cells attach to antigens on infectedcells for example cancerous cells and destroy them completely bymaking holes and infusing enzymes into the cells. Just as the nameexplains, helper T cells help other immune cells. Some helper T cellshelp B cells manufacture antibodies against intruding antigens. OtherT helper cells activate killer T cells to destroy infected or assistin activating macrophages, enabling them to consume infected cellsmore efficiently. A macrophage is a huge white blood cell that is anamoeba –like organism, and it main function is to clean human bodyof any microscopic debris and attackers. This big white bold cell hasthe ability to establish where viruses, intruders and parasites andeat or consume them. HIV interrupts the immune deficiency process bydirectly infecting the T-cells. Initially, healthy immune systems getrid of HIV as much as it can but with time, HIV overpowers thesystem. Once the virus infects the T-cells, they are activated tocreate new viruses instead of helping other immune cells.Furthermore, numerous helperT-cellsget cracked in the HIV duplication process.

Thefunction of complement systems and how HIV turns against the humanbody

Accordingto Atkinson&amp Frank (2006), the complement system is an enzyme cascade thatis a set of blood and cell surface protein to enhance the abilitiesof antibodies to fight off antigens from an organism. Despite thefact that the complement system is a great defender of the immunesystem against foreign intruders, HIV uses it to replicate, spreadand remain in the human body. Therefore, the new treatments coming upfor HIV is to suppress the complement system in order to ensure itdoes not overpower the immune system when turned against the body byHIV.


Atkinson,J. P., &amp Frank, M. M. (2006). Bypassing complement: evolutionarylessons and future implications.&nbspJournalof Clinical Investigation,&nbsp116(5),1215.

Isaacman-Beck,J., Hermann, E. A., Yi, Y., Ratcliffe, S. J., Mulenga, J., Allen, S.,… &amp Collman, R. G. (2009). Heterosexual transmission of humanimmunodeficiency virus type 1 subtype C: Macrophage tropism,alternative coreceptor use, and the molecular anatomy of CCR5utilization.&nbspJournalof virology,&nbsp83(16),8208-8220.

Perez,M. A. S., Fernandes, P. A., &amp Ramos, M. J. (2010). Substraterecognition in HIV-1 protease: a computational study.&nbspTheJournal of Physical Chemistry B,&nbsp114(7),2525-2532.

WorldHealth Organization, &amp UNICEF. (2010). Towards universal access:scaling up priority HI.