UniKin1: A Universal, Non-Species-Specific Whole Cell Kinetic Model

ABSTRACTA small subset of major immunoreactive proteins have been identified inEhrlichia chaffeensisandEhrlichia canis, including three molecularly and immunologically characterized pairs of immunoreactive tandem repeat protein (TRP) orthologs with major continuous species-specific epitopes within acidic tandem repeats (TR) that stimulate strong antibody responses during infection. In this study, we identified a fourth major immunoreactive TR-containing ortholog pair and defined a major cross-reactive epitope in homologous nonidentical 24-amino-acid lysine-rich TRs. Antibodies from patients and dogs with ehrlichiosis reacted strongly with recombinant TR regions, and epitopes were mapped to the N-terminal TR region (18 amino acids) inE. chaffeensisand the complete TR (24 amino acids) inE. canis. Two less-dominant epitopes were mapped to adjacent glutamate/aspartate-rich and aspartate/tyrosine-rich regions in the acidic C terminus ofE. canisTRP95 but not inE. chaffeensisTRP75. Major immunoreactive proteins inE. chaffeensis(75-kDa) andE. canis(95-kD) whole-cell lysates and supernatants were identified with TR-specific antibodies. Consistent with other ehrlichial TRPs, the TRPs identified in ehrlichial whole-cell lysates and the recombinant proteins migrated abnormally slow electrophoretically a characteristic that was demonstrated with the positively charged TR and negatively charged C-terminal domains.E. chaffeensisTRP75 andE. canisTRP95 were immunoprecipitated with anti-pTyr antibody, demonstrating that they are tyrosine phosphorylated during infection of the host cell.

Download Full-text

Serological Diagnostics of Lyme Borreliosis: Comparison of Universal andBorreliaSpecies-Specific Tests Based on Whole-Cell and Recombinant Antigens

Journal of Clinical Microbiology ◽

10.1128/jcm.00601-18 ◽

2018 ◽

Vol 56 (11) ◽

Cited By ~ 4

Author(s):

Petr Kodym ◽

Zuzana Kurzová ◽

Dagmar Berenová ◽

Dušan Pícha ◽

Dita Smíšková ◽

...

Keyword(s):

Negative Predictive Value ◽

Predictive Value ◽

Erythema Migrans ◽

Clinical State ◽

Test Results ◽

Recombinant Antigens ◽

Whole Cell ◽

Content Type ◽

Diagnostic Parameters ◽

Species Specific

ABSTRACTThe study compares diagnostic parameters of different commercial serological kits based on three different antigen types and correlates test results with the status of the patient'sBorreliainfection. In total, 8 IgM and 8 IgG kits were tested, as follows: enzyme-linked immunosorbent assay (ELISA) (Euroimmun) based on whole-cell antigen, 3 species-specific enzyme immunoassays (EIAs) (TestLine), Liaison chemiluminescence (DiaSorin), ELISA-Viditest (Vidia), EIA, and Blot-Line (TestLine) using recombinant antigens. All tests were performed on a panel of 90 samples from patients with clinically characterized borreliosis (53 with neuroborreliosis, 32 with erythema migrans, and 5 with arthritis) plus 70 controls from blood donors and syphilis patients. ELISA based on whole-cell antigens has superior sensitivity and superior negative predictive value and serves as an excellent screening test, although its specificity and positive predictive values are low. Species-specific tests have volatile parameters. Their low sensitivity and low negative predictive value handicap them in routine diagnostics. Tests with recombinant antigens are characterized by high specificity and high positive predictive value and have a wide range of use in diagnostic practice. Diagnostic parameters of individual tests depend on the composition of the sample panel. Only a small proportion of contradictory samples giving both negative and positive results is responsible for discrepancies between test results. Correlation of test results with the patient's clinical state is limited, especially in the erythema migrans group with high proportions of negative and contradictory results. In contrast, IgG test results in the neuroborreliosis group, which are more concordant, show acceptable agreement withBorreliastatus.

Download Full-text

A CELL KINETIC MODEL TO EXPLAIN THE TIME OF APPEARANCE OF SKIN REACTION AFTER X-RAYS OR ULTRAVIOLET LIGHT IRRADIATION

Cell Proliferation ◽

10.1111/j.1365-2184.1979.tb00150.x ◽

1979 ◽

Vol 12 (3) ◽

pp. 281-289

Author(s):

S. E. Al-Barwari ◽

C. S. Potten

Keyword(s):

Kinetic Model ◽

Skin Reaction ◽

Ultraviolet Light ◽

Light Irradiation ◽

X Rays ◽

Cell Kinetic ◽

Ultraviolet Light Irradiation ◽

A Cell

Download Full-text

Testing theoretical minimal genomes using whole-cell models

10.1101/2020.03.26.010363 ◽

2020 ◽

Cited By ~ 1

Author(s):

Joshua Rees-Garbutt ◽

Jake Rightmyer ◽

Oliver Chalkley ◽

Lucia Marucci ◽

Claire Grierson

Keyword(s):

In Silico ◽

Cell Model ◽

Mycoplasma Genitalium ◽

Essential Genes ◽

Cellular Division ◽

Whole Cell ◽

Gene Sets ◽

Dividing Cells ◽

Species Specific

AbstractThe minimal gene set for life has often been theorised, with at least ten produced for Mycoplasma genitalium (M. genitalium). Due to the difficulty of using M. genitalium in the lab, combined with its long replication time of 12 - 15 hours, none of these theoretical minimal genomes have been tested, even with modern techniques. The publication of the M. genitalium whole-cell model provided the first opportunity to test them, simulating the genome edits in-silico. We simulated eight minimal gene sets from the literature, finding that they produced in-silico cells that did not divide. Using knowledge from previous research, we reintroduced specific essential and low essential genes in-silico; enabling cellular division. This reinforces the need to identify species-specific low essential genes and their interactions. Any genome designs created using the currently incomplete and fragmented gene essentiality information, will very likely require in-vivo reintroductions to correct issues and produce dividing cells.

Download Full-text