Chlamydia protein, gene sequence and uses thereof

Details Chlamydia protein, gene sequence and uses thereof Chlamydia protein, gene sequence and uses thereof

2000-07-06

2003-11-04

Kunz, Gary (Department: 1647)

Chemistry: molecular biology and microbiology

Micro-organism, tissue cell culture or enzyme using process...

Recombinant dna technique included in method of making a...

C435S252300, C435S320100, C536S023100

Reexamination Certificate

active

06642023

ABSTRACT:

FIELD OF THE INVENTION
The present invention generally relates to a high molecular weight (“HMW”) protein of Chlamydia, the amino acid sequence thereof, and antibodies, including cytotoxic antibodies, that specifically bind the HMW protein. The invention further encompasses prophylactic and therapeutic compositions comprising the HMW protein, a fragment thereof, or an antibody that specifically binds the HMW protein or a portion thereof or the nucleotide sequence encoding the HMW protein or a fragment thereof, including vaccines. The invention additionally provides methods of preventing, treating or ameliorating disorders in mammals and birds related to Chlamydia infections and for inducing immune responses to Chlamydia. The invention further provides isolated nucleotide sequences and degenerate sequences encoding the HMW protein, vectors having said sequences, and host cells containing said vectors. Diagnostic methods and kits are also included.
BACKGROUND OF THE INVENTION
Chlamydia are prevalent human pathogens causing disorders such as sexually transmitted diseases, respiratory diseases including pneumonia, neonatal conjunctivitis, and blindness. Chlamydia are obligate intracellular bacteria that infect the epithelial lining of the lung, conjunctivae or genital tract. The most common species of Chlamydia include
Chlamydia trachomatis, Chlamydia psittaci, Chlamydia pecorum
and
Chlamydia pneumoniae
. Recently, the newly designated species of Chlamydia,
C. pneumoniae
(formerly
C. trachomatis
TWAR), has been implicated as a major cause of epidemic human pneumonitis and perhaps may play a role in atherosclerosis.
There are currently 18 recognized
C. trachomatis
serovars, causing trachoma and a broad spectrum of sexually transmitted diseases: with the A, B and C serovars being most frequently associated with trachoma, while the D-K serovars are the most common cause of genital infections.
C. trachomatis
is the major cause of sexually transmitted disease in many industrialized countries, including the United States. While the exact incidence of
C. trachomatis
infection in the U.S. is not known, current epidemiological studies indicate that more than 4 million chlamydial infections occur each year, compared to an estimated 2 million gonococcal infections. While all racial, ethnic and socioeconomic groups are affected, the greatest prevalence of chlamydial infections occur among young, 12 to 20 year-old, sexually active individuals. Most genitourinary chlamydial infections are clinically asymptomatic. Prolonged carriage in both men and women is common. As many as 25% of men and 75% of women diagnosed as having chlamydial infections have no overt signs of infection. As a consequence, these asymptomatic individuals constitute a large reservoir that can sustain transmission of the agent within the community.
Far from being benign, serious disease can develop from these infections including: urethritis, lymphogranuloma venereum (LGV), cervicitis, and epididymitis in males. Ascending infections from the endocervix commonly gives rise to endometritis, pelvic inflammatory disease (PID) and salpingitis which can cause tubal occlusion and lead ultimately to infertility.
C. trachomatis
infection of neonates results from perinatal exposure to the mother's infected cervix. Nearly 70% of neonates born vaginally to mothers with chlamydial cervicitis become infected during delivery. The mucus membranes of the eye, oropharynx, urogenital tract and rectum are the primary sites of infection. Chlamydial conjunctivitis has become the most common form of ophthalmia neonatorum. Approximately 20-30% of exposed infants develop inclusion conjunctivitis within 14 days of delivery even after receiving prophylaxis with either silver nitrate or antibiotic ointment.
C.trachomatis
is also the leading cause of infant pneumonia in the United States. Nearly 10-20% of neonates delivered through an infected cervix will develop chlamydial pneumonia and require some type of medical intervention.
In developing countries, ocular infections of
C.trachomatis
cause trachoma, a chronic follicular conjunctivitis where repeated scar formation leads to distortion of the eyelids and eventual loss of sight. Trachoma is the world's leading cause of preventable blindness. The World Health Organization estimates that over 500 million people worldwide, including about 150 million children, currently suffer from active trachoma and over 6 million people have been blinded by this disease.
In industrialized countries, the costs associated with treating chlamydial infections are enormous. In the U.S., the annual cost of treating these diseases was estimated at $2.5-3 billion in 1992 and has been projected to exceed $8 billion by the year 2000.
One potential solution to this health crisis would be an effective chlamydial vaccine. Several lines of evidence suggest that developing an effective vaccine is feasible.
Studies in both humans and primates have shown that short-term protective immunity to
C. trachomatis
can be produced by vaccinating with whole Chlamydia. However, protection was characterized as short lived, serovar specific, and due to mucosal antibody. Additionally, in some vaccinees disease was exacerbated when these individuals became naturally infected with a serovar different from that used for immunization. This adverse reaction was ultimately demonstrated to be due to a delayed-type hypersensitivity response. Thus, the need exists to develop a subunit-based chlamydial vaccine capable of producing an efficacious but nonsensitizing immune response. Such a subunit vaccine may need to elicit both mucosal neutralizing secretory IgA antibody and/or cellular immune response to be efficacious.
Subunit vaccine development efforts to date have focused almost exclusively on the major outer membrane protein (MOMP). MOMP is an integral membrane protein of approximately 40 kDa in size and comprises up to about 60% of the infectious elementary body (EB) membrane protein (Caldwell, H. D., J. Kromhout, and L. Schachter. 1981
. Infect. Immun
., 31:1161-1176). MOMP imparts structural integrity to the extracellular EB and is thought to function as a porin-like molecule when the organism is growing intracellularly and is metabolically active. With the exception of four surface exposed variable domains (VDI-VDIV), MOMP is highly conserved among all 18 serovars. MOMP is highly immunogenic and can elicit a local neutralizing anti-Chlamydia antibody. However, problems exists with this approach.
To date, most MOMP-specific neutralizing epitopes that have been mapped are located within the VD regions and thus give rise only to serovar-specific antibody. Attempts to combine serovar-specific epitopes in various vaccine vectors (e.g. poliovirus) to generate broadly cross-reactive neutralizing antibodies have been only marginally successful (Murdin, A. D., H. Su, D. S. Manning, M. H. Klein, M. J. Parnell, and H. D. Caldwell. 1993
. Infect. Immun
., 61:4406-4414; Murdin, A. D., H. Su, M. H. Klein, and H. D. Caldwell. 1995
. Infect. Immun
., 63:1116-1121).
Two other major outer membrane proteins in
C. trachomatis
, the 60 kDa and 12 kDa cysteine-rich proteins, as well as the surface-exposed lipopolysaccharide, are highly immunogenic but, unlike MOMP, have not been shown to induce a neutralizing antibody (Cerrone et al., 1991
, Infect. Immun
., 59:79-90). Therefore, there remains a need for a novel subunit-based chlamydial vaccine.
SUMMARY OF THE INVENTION
An object of the present invention is to provide an isolated and substantially purified high molecular weight protein of a Chlamydia sp. (“HMW protein”), wherein the HMW protein has an apparent molecular weight of about 105-115 kDa, as determined by SDS-PAGE, or a fragment or analogue thereof. Preferably the HMW protein has substantially the amino acid sequence of any of SEQ ID Nos.: 2, 15 and 16. Preferred fragments of the HMW protein include SEQ ID Nos: 3, 17, and 25-37. As used herein, “substantially the sequence” is intended to mean that the sequence is at least 80%, mor

Affiliated with

Also associated with

Rating

Chlamydia protein, gene sequence and uses thereof does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Chlamydia protein, gene sequence and uses thereof, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Chlamydia protein, gene sequence and uses thereof will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3177281