ReMed 2016 ReMed Magazine N°0 - HIV/AIDS | Page 6

(Figure-2- ), any alteration of their function, will lead to
a sever condition of vulnerability with opportunistic
infections, tumors and organs failure known as AIDS
(Acquired Immune Deficiency Syndrome). HIV may
infect other cell types such as macrophage and dendritic
cells, both altering furthermore the immune function.
Abstract: The emergence of viral infections has
established the importance of the immune system to keep
the integrity of our bodies against a hostile, full of
pathogens environment, AIDS is the best example
illustrating this notion with its severe consequences
and eventually exposure to death.
Keywords: AIDS, HIV, virus, LTCD4
Human immunodeficiency Virus
(HIV)
Figure-1-: HIV structure (HIV subtype1)
Discovered in 1981, due to an unusual
consumption rate of a drug used to treat pneumocystis
pneumonia, HIV (Human Immunodeficiency Virus) has
been identified as a group of retroviruses (2 subtypes:
HIV-1 and HIV-2) originating from some non-human
primate species from West Africa , as any virus
(Infectious agents with the capacity to invade any living
cell and alter its genome in order to assure viral
replication using this same cell’s resources in a process
known as obligate intracellular parasitism), HIV has a
rather simple structure (Figure-1-), two single-stranded
RNA chains which code for proteins needed in viral
cycles and a few complexes of enzymes (rTranscriptase,
integrase -whose function will be explained in later
sections-) all surrounded by a capsid delimiting the viral
core, and a viral envelope of a lipidic nature (Explaining
the fragility of viral particles, and their direct mode of
transmission), this last, contains a glycoprotein surface
antigen complex (gp41/gp120) major factor of HIV’s
specific tropism to immunity system elements, other
elements exist in between the core and matrix, as it is the
case of an enzyme “protease” used in the process of
invasion to alter the host cell antiviral complexes, this
past description concerns the independent extracellular
form, as of the existence of heterogeneous intracellular
forms.
As mentioned before, HIV has a particular viral tropism,
determined by the specificity of epitopes exposed in its
surface. Mainly infected, lymphocytes T CD4+
(LTCD4) are vital elements of specific immune
responses (Whose integrity is crucial for its efficiency
against the different threats the human body may face),
standing in the heart of the immune response regulation
process in both the cellular and the humoral pathways
HIV/AIDS
5
(Thomas Splettstoesser 2014 © )
The virus transmission
As any conventional transmissible agent, HIV obeys to
the classic scheme of transmission: from an infected
organism with the sufficient blood viral load, the viral
particle is transmitted to the new host to cause the
infection primarily, and the state of immunodeficiency
later on (after a variable period of time), but the fragile
structure of the virus (lipidic envelope mainly) limits its
propagation capacity through respiratory, digestive and
cutaneous pathways, as a results, the major modes of
transmission imply biological bodily fluids, such as
blood, genital secretions and breast milk, which can
contain both independent and intracellular forms of
HIV. Sexual contact (all unprotected practices
combined), is by far the main path, with the highest
transmission risk (more than half new cases every year),
the other ways include uncontrolled blood products