HUMAN PAPILLOMA VIRUS (HPV)

HUMAN PAPILLOMA VIRUS HUMAN PAPILLOMA VIRUS (HPV) (HPV) By: By: Nathalia Cruz Nathalia Cruz What is a Virus? What is a Virus? ► Exceptionally simple living microbes. Exceptionally simple living microbes. ► Contain a single type of nucleic acid (DNA or RNA) and a Contain a single type of nucleic acid (DNA or RNA) and a protein coat. protein coat. ► Obligatory intracellular parasites. Obligatory intracellular parasites. ► Range from 20 to 14.000 nm in length. Range from 20 to 14.000 nm in length. ► It’s classification is based on type of nucleic acid, strategy It’s classification is based on type of nucleic acid, strategy for replication, and morphology for replication, and morphology HUMAN PAPILLOMA VIRUS HUMAN PAPILLOMA VIRUS ► HPV is the virus that causes warts. HPV is the virus that causes warts. ► More than 100 different kinds, 30-some of this cause More than 100 different kinds, 30-some of this cause genital HPV. genital HPV. ► Spread by sexual contact or from mother to baby. Spread by sexual contact or from mother to baby. ► Genital warts appear 6 weeks to 8 months after contact Genital warts appear 6 weeks to 8 months after contact with an HPV infected person. with an HPV infected person. HPV HPV ► The most common sexually transmitted disease worldwide. The most common sexually transmitted disease worldwide. ► Certain types of HPV are linked with cervical cancer. Certain types of HPV are linked with cervical cancer. ► Divided into 2 subcategories: Genital Warts and Cervical Divided into 2 subcategories: Genital Warts and Cervical Dysplasia. Dysplasia. ► Most people do not know they have it. Most people do not know they have it. ► There are high risk and low risk types of it. There are high risk and low risk types of it. HISTORY HISTORY ► The papillomaviruses are part of the PAPOVAVIRIDAE The papillomaviruses are part of the PAPOVAVIRIDAE family of DNA tumor viruses. family of DNA tumor viruses. ► First discovered in the early 40’s. First discovered in the early 40’s. ► Gained notoriety in the early 80’s when it was discovered Gained notoriety in the early 80’s when it was discovered that some types of HPV caused cervical cancer. that some types of HPV caused cervical cancer. MORPHOLOGY MORPHOLOGY ► Papilloma virus genome is circular covalently closed double Papilloma virus genome is circular covalently closed double stranded DNA of about 8 kbp. stranded DNA of about 8 kbp. ► All PV genes are coded in one of the 2 DNA strands All PV genes are coded in one of the 2 DNA strands utilizing the alternative splicing for the individual utilizing the alternative splicing for the individual expression of each gene. expression of each gene. ► Papillomavirus expression is characterized by a large array Papillomavirus expression is characterized by a large array of mRNAs cells coding for different genes. of mRNAs cells coding for different genes. ► 55 nm in diameter. 55 nm in diameter. APPEARANCE APPEARANCE MECHANISM OF INFECTION MECHANISM OF INFECTION ► All PV exhibit extreme specificity for infection on epithelial All PV exhibit extreme specificity for infection on epithelial cells. cells. ► The papillomavirus epitheliotrophy resides in the The papillomavirus epitheliotrophy resides in the interaction of specific transmission factors with the viral interaction of specific transmission factors with the viral regulatory region LCR. regulatory region LCR. ► The infection normally results in hyperproliferation of the The infection normally results in hyperproliferation of the host cell and may lead to transformation and host cell and may lead to transformation and immortalization. immortalization. GENITAL WARTS GENITAL WARTS ► Sometimes called condylomata acuminata. Sometimes called condylomata acuminata. ► Are soft, moist or flesh colored, and appear in the genital Are soft, moist or flesh colored, and appear in the genital area within weeks or months after infection. area within weeks or months after infection. ► Sometimes appear in clusters and are either raised or flat, Sometimes appear in clusters and are either raised or flat, small or large. small or large. ► Women: appear in the vulva, cervix, vagina and anus. Women: appear in the vulva, cervix, vagina and anus. ► Men: Can appear on the scrotum or penis. Men: Can appear on the scrotum or penis. LIFE CYCLE (HPV-16) LIFE CYCLE (HPV-16) ► Starts with the infection of the host cell. Starts with the infection of the host cell. ► The virus DNA is released within the nucleus The virus DNA is released within the nucleus ► Numerous cellular transcription factors interact Numerous cellular transcription factors interact with the non-coding viral regulatory region (LCR), with the non-coding viral regulatory region (LCR), starting transcription of the two hpv-16 starting transcription of the two hpv-16 transforming early genes (E6 and E7). transforming early genes (E6 and E7). ► The transforming proteins interact with the cellular The transforming proteins interact with the cellular antioncogenic regulator p53 disrupting the cell antioncogenic regulator p53 disrupting the cell cycle. cycle. [...]... ► There is currently no cure for human papillomavirus Once an individual is infected, he or she carries the virus for life even if genital warts are removed The development of a vaccine against HPV is under way, but is still not available If left untreated, some genital warts may regress on their own SOURCES ► ► ► ► ► http://cinvestav.mx/genetica/MyFiles/Papillomavirus/PAPep i.html http://www.life.umd.edu/classroom/bsci424/BSCI223WebS . HUMAN PAPILLOMA VIRUS HUMAN PAPILLOMA VIRUS (HPV) (HPV) By: By: Nathalia Cruz Nathalia Cruz What is a Virus? What is a Virus? ► Exceptionally. replication, and morphology HUMAN PAPILLOMA VIRUS HUMAN PAPILLOMA VIRUS ► HPV is the virus that causes warts. HPV is the virus that causes warts. ► More