Intended use
High throughput genotyping of 14 different Chlamydia trachomatis serovars.

The LMNX kit Ct (Chlamydia trachomatis) Genotyping is an in vitro high-throughput assay based on microsphere suspension technology. Two primer sets are used for the qualitative identification of 14 different Ct serovars (i.e. A, B/Ba, C, D/Da, E, F, G/Ga, H, I/Ia, J, K, L1, L2/L2a and L3). The LMNX kit Ct Genotyping is a Research Use Only (RUO) test. By serogroup and serovar identification in Ct testing, epidemiological research could further investigate possible clinical relevance of specific Ct serovars, or outbreaks in subpopulations.

Summary and explanation
Chlamydia trachomatis (Ct) is the most prevalent sexually transmitted bacterial pathogen. Most infections remain asymptomatic, but when left untreated, these infections can lead to serious diseases, such as pelvic inflammation, ectopic pregnancy and tubal infertility. Ct can be divided into three serogroups and subsequently into 19 serovars. The different serovars of Ct display diverse biological activities. Serovars A, B/Ba and C are commonly associated with an ocular disease (trachoma). Serovars D/Da, E, F, G/Ga, H, I/Ia, J and K are common in the urogenital tract and can sometimes be detected in the respiratory tract of infants, whereas serovars B and C are rarely detected in the urogenital tract. The serovars L1, L2/L2a and L3 are mainly detected in the inguinal lymph nodes and the rectum and may cause lymphogranuloma venereum. Laboratory diagnosis of Ct infection is routinely performed by molecular methods such as PCR or liquid hybridization. Most assays aim at detection of the multi copy cryptic plasmid which ensures high sensitivity but such assays have no ability to distinguish different serogroups and serovars.
The Ct Genotyping RHA kit is a follow-up for amplification using the LBP Ct PCR Primer set. This multiplex PCR detects Ct infections by targeting a 89 bp region in the cryptic plasmid and a 162-165 bp region in the genome. Amplification of the cryptic plasmid allows detection with high sensitivity, whereas the genomic amplicon enables the identification of serovar and serogroup by specific probes.
By detecting both the cryptic plasmid and the genomic Ct DNA the Ct Genotyping RHA kit circumvents false-negative test results in case of emerging variants that have been described. 
The novel LMNX Ct assay combines CT detection and subtyping of 3 serogroups (B, C and intermediate), and 19 Ct serovars (A, B/Ba, C, D/Da, E, F, G/Ga, H, I/Ia, J, K, L1m L2/L2a and L3) using microsphere suspension technology. It offers a high-throughput alternative for separate detection and genotyping with the RHA kit CT Genotyping.

Principle of the procedure
The LMNX Ct Genotyping is based on the reverse hybridization of amplicons obtained by PCR of DNA extracted from clinical specimens. The PCR can be performed either by use of the primers in the kit or with the amplification part of the Chlamydia trachomatis Detection kit (a PCR/DNA-Elisa screenings test). Denatured amplicons are hybridized with specific oligonucleotide probes, which are immobilized on microspheres. Each oligonucleotide probe is bound to a specific coloured microsphere. Microspheres with bound amplimers are individually detected and identified in an automated detection system.

Ordering information
REF: L-4149 LMNX kit CT Genotyping 96 tests

Related product
REF: K-45 DNA ELISA kit Ct 96 tests
REF: S-1021 RHA kit CT Genotyping 20 tests

1) Quint et al. (2011), Evaluation of a novel Chlamydia trachomatis microsphere suspension assay for detection and genotyping of the different serovars in clinical samples. J Mol Diagn 13, 152-9.