Abstract: The 28-kDa outer membrane proteins (P28) of Ehrlichia chaffeensis are encoded by a multigene family consisting of 21 members located in a 23-kb DNA fragment in the genome of E. chaffeensis. Fifteen of these proteins are claimed herein as novel sequences. The amino acid sequence identity of the various P28 proteins was 20-83%. Six of 10 tested p28 genes were actively transcribed in cell culture grown E. chaffeensis. RT-PCR also indicated that each of the p28 genes was monocistronic. These results suggest that the p28 genes are active genes and encode polymorphic forms of the P28 proteins. The P28s were also divergent among different isolates of E. chaffeensis. The large repertoire of the p28 genes in a single ehrlichial organism and antigenic diversity of the P28 among the isolates of E. chaffeensis suggest that the P28s may be involved in immune avoidance.

Abstract: Novel genes encoding homologous immunoreactive thio-disulfide oxidoreductases, or disulfide bond formation (Dsb) proteins from Ehrlichia chaffeensis and Ehrlichia canis are disclosed. While the E. chaffeensis and E. canis Dsb proteins are at most only 31% or less homologous to other known Dsb proteins, the Ehrlichia Dsbs contain a cysteine active site, Cys-Gly-Tyr-Cys, similar to those in known Dsb proteins. As predicted by 15-amino acid identical N-terminal signal peptides, the proteins are primarily localized in the periplasm of E. chaffeensis and E. canis, possibly playing a role in antigenicity and pathogenesis. The present invention provides the nucleotide and amino acid sequences and expression vectors for the E. chaffeensis and E. canis dsb genes, antisera directed against the proteins, and kits to determine whether an individual or animal is infected with a given species of Ehrlichia.

Abstract: The present invention is directed to the cloning, sequencing and expression of homologous immunoreactive 28-kDa protein genes, p28-1, -2, -3, -5; -6, -7, -9, from a polymorphic multiple gene family of Ehrlichia canis. Further disclosed is a multigene locus encoding all nine homologous 28-kDa protein genes of Ehrlichia canis. Recombinant Ehrlichia canis 28-kDa proteins react with convalescent phase antiserum from an E. canis-infected dog, and may be useful in the development of vaccines and serodiagnostics that are particularly effective for disease prevention and serodiagnosis.

Abstract: A filter system including a housing with an intake and an outlet, a pleated carbon filter disposed between the intake and the outlet for filtering out vapors entering the intake, and a hydrophobic solution dispersed about the pleated carbon filter to inhibit adsorption of water thereby increasing the adsorption capacity of the pleated carbon filter especially in high relative humidity environments. The hydrophobic solution is selected so that it does not decrease the adsorption capacity of the carbon filter. Also disclosed is a method of making such a filter.

Abstract: The present invention is directed to the cloning, sequencing and expression of a conserved immunoreactive 28-kDa protein gene (P28) from a polymorphic multiple gene family of Ehrlichia canis. E. canis P28 has an 834-bp open reading frame encoding a protein of 278 amino acids with four variable regions, and shares similar surface-exposed regions, antigenicity and T-cell motifs with E. chaffeensis P28. Also disclosed is that recombinant E. canis P28 protein reacts with convalescent phase antiserum from an E. canis-infected dog.

Abstract: The present invention is directed to the cloning, sequencing and expression of homologous immunoreactive 28-kDa protein genes, p28-1, -2, -3, -5, -6, -7, -9, from a polymorphic multiple gene family of Ehrlichia canis. Further disclosed is a multigene locus encoding all nine homologous 28-kDa protein genes of Ehrlichia canis. Recombinant Ehrlichia canis 28-kDa proteins react with convalescent phase antiserum from an E. canis-infected dog, and may be useful in the development of vaccines and serodiagnostics that are particularly effective for disease prevention and serodiagnosis.

Abstract: The present invention is directed to isolated nucleic acid molecules encoding Rickettsia felis outer membrane proteins (R. felis omp). Expression vectors and host cells comprising the nucleic acid molecules are also provided, as well as methods for increasing or decreasing the expression of R. felis omp in host cells. The invention further provides a method of screening a substance for the ability of the substance to modify R. felis omp function, and a method for isolating other R. felis omp molecules. DNA oligomers capable of hybridizing to the nucleic acid molecule encoding the R. felis omp are provided, which can be used to detect R. felis omp in a sample. An isolated R. felis omp is also provided. Antibodies specific for the protein, and fragments thereof, are provided, as are compositions comprising the protein and a compatible carrier. The subject invention further provides a method of preventing R. felis infections by R. felis present in a carrier host, and a method of reducing R.

Abstract: The present invention is directed to the cloning, sequencing and expression of homologous immunoreactive 28-kDa protein genes, ECa28-1 and ECa28SA3, from a polymorphic multiple gene family of Ehrlichia canis. A complete sequence of another 28-kDa protein gene, ECaSA2, is also provided. Further disclosed is a multigene locus encoding all five homologous 28-kDa protein genes of Ehrlichia canis. Recombinant Ehrlichia canis 28-kDa proteins react with convalescent phase antiserum from an E. canis-infected dog.

Abstract: The 28-kDa outer membrane proteins (P28) of Ehrlichia chaffeensis are encoded by a multigene family consisting of 21 members located in a 23-kb DNA fragment in the genome of E. chaffeensis. Fifteen of these proteins are claimed herein as novel sequences. The amino acid sequence identity of the various P28 proteins was 20-83%. Six of 10 tested p28 genes were actively transcribed in cell culture grown E. chaffeensis. RT-PCR also indicated that each of the p28 genes was monocistronic. These results suggest that the p28 genes are active genes and encode polymorphic forms of the P28 proteins. The P28s were also divergent among different isolates of E. chaffeensis. The large repertoire of the p28 genes in a single ehrlichial organism and antigenic diversity of the P28 among the isolates of E. chaffeensis suggest that the P28s may be involved in immune avoidance.

Abstract: The present invention is directed to the cloning, sequencing and expression of homologous immunoreactive 28-kDa protein genes, p28-1, -2, -3, -5, -6, -7, -9, from a polymorphic multiple gene family of Ehrlichia canis. Further disclosed is a multigene locus encoding all nine homologous 28-kDa protein genes of Ehrlichia canis. Recombinant Ehrlichia canis 28-kDa proteins react with convalescent phase antiserum from an E. canis-infected dog, and may be useful in the development of vaccines and serodiagnostics that are particularly effective for disease prevention and serodiagnosis.

Abstract: Canine monocytic ehrlichiosis, caused by Ehrilichia canis is a potentially fatal disease of dogs that requires rapid and accurate diagnosis in order to initiate appropriate therapy leading to a favorable prognosis. In the invention described herein, a new immunoreactive E. canis surface protein gene of 1170-bp was cloned, which encodes a protein with a predicted molecular mass of 42.6 kilodaltons (P43). The P43 gene was not found in E. chaffeensis DNA by Southern blot, and antisera against recombinant P43 (rP43) did not react with E. chaffeensis by IFA. The P43 was located on the surface of E. canis by immunoelectron microscopy. Forty-two dogs exhibiting signs and/or hematologic abnormalities associated with canine ehrlichiosis were tested by IFA and by Western immunoblot. Among the 22 samples that were IFA positive for E. canis, 100% reacted with the rP43, 96% with the rP28, and 96% with the rP140. The specificity of the recombinant proteins compared to IFA was 96% for rP28, 88% for P43 and 63% for P140.

Abstract: The present invention provides a 120-kDa protein gene of Ehrlichia canis, amplified by PCR using primers derived from the DNA sequences flanking the Ehrlichia chaffeensis 120-kDa protein gene. The recombinant E. canis 120-kDa protein contains 14 tandem repeat units with 36 amino acids each. The repeat units are hydrophilic and predicted to be surface-exposed. Also disclosed is that the recombinant E. canis 120-kDa protein is antigenic and reacts with sera from dogs convalescent from canine ehrlichiosis.

Abstract: Disclosed is an isolated gene encoding a 120 kDa immunodominant antigen of Ehrlichia chaffeensis. The 120-kDa protein is one of the immunodominant proteins of E. chaffeensis that stimulates production of specific antibodies in infected humans. Also disclosed are the amino acid sequence of the 120 kDa antigen. Methods of producing a recombinant 120 kDa antigen and therapeutic methods of use of the antigen are also disclosed.

Abstract: A vapor extraction apparatus includes a gel sorbent capable of absorbing vapor directly into the liquid state and capable of disgorging the absorbed liquid in a phase-transition. The apparatus includes a housing adapted for movement from a first position, where it is exposed to a vapor-containing gas stream and a first environmental condition, and capable of moving to a second position, where it is exposed to a second environmental condition. A gel sorbent is disposed on at least one surface of the housing. The gel sorbs vapor from the gas stream as liquid when the sorbent is in its first position. The sorbent disgorges the liquid during phase-transition collapse when it is in the second position. A method of extracting vapor from a process gas stream includes contacting a phase transition gel sorbent with vapor under conditions sufficient for the gel sorbent to undergo a phase transition and absorb vapor as liquid inside the gel sorbent.

Abstract: A vapor extraction apparatus includes a gel sorbent capable of absorbing vapor directly into the liquid state and capable of disgorging the absorbed liquid in a phase-transition. The apparatus includes a housing adapted for movement from a first position, where it is exposed to a vapor-containing gas stream and a first environmental condition, and capable of moving to a second position, where it is exposed to a second environmental condition. A gel sorbent is disposed on at least one surface of the housing. The gel sorbs vapor from the gas stream as liquid when the sorbent is in its first position. The sorbent disgorges the liquid during phase-transition collapse when it is in the second position. A method of extracting vapor from a process gas stream includes contacting a phase transition gel sorbent with vapor under conditions sufficient for the gel sorbent to undergo a phase transition and absorb vapor as liquid inside the gel sorbent.

Abstract: A demand defrost controller employs temperature measurements taken at the outlet of the discharge air curtain and the inlet of the air return to determine the need for defrost. If the difference between these temperature measurements exceeds a set point for a predetermined sustained period of time and a minimum amount of time has elapsed since the last defrost of the case, defrost is initiated. Regardless of the value of the temperature difference, defrost is initiated if elapsed time since the last defrost exceeds a specified maximum time between defrosts for the case. Defrost can be terminated on the basis of time and/or temperature. The demand defrost controller can also control display case temperature and can be applied to independently control multiple display case circuits.