PubMed Health⌕ Search

Biomedical subjects

F Hesford

Publications and source records attributed to F Hesford.

6 recordsLinked to original sources
PubMed1991

Production of alloantibodies against bovine B-lymphocyte antigens.

A series of alloimmunizations were carried out between BoLA class I antigen typed bulls, with the aim of generating class II specific reagents. Of the antisera produced, seven demonstrated exclusively B cell reactivity. Another 19 sera reacted with both T and B cells from some animals and with B cells only in other cases. Suitable buffy coat absorptions removed T cell reactivity from some sera and shortened broader reactivities in certain B cell specific sera. Typing of separated T and B cells from related and unrelated animals permitted clustering of the sera into four groups. These groups behave as allelic specificities. The class II nature of the recognized structures was strongly indicated by two further pieces of evidence. The presence or absence of particular B cell antigens correlated with reactivity of cells in one-way mixed lymphocyte cultures. In addition, a number of the B cell specific sera were characterized by immunoprecipitation of radiolabelled lymphocytes. The precipitated products corresponded in molecular weight to alpha and beta chains of MHC class II dimers, as has been found in this and other species.

Animals↗
PubMed1989

Biochemical evidence that equine leucocyte antigens W13, W22 and W23 are present on horse major histocompatibility complex class II molecules.

A number of horse alloantisera were characterized biochemically as being directed against MHC class I or class II antigens by immunoprecipitation of the corresponding antigens from lysates of biosynthetically radioactively labelled lymphocytes and determination of their molecular weights by SDS-PAGE and fluorography. Sera recognizing A2 and A3 specificities precipitated antigens of 44,000 Daltons molecular weight (class I heavy chain), whereas sera with specificities W13, W22 and W23 precipitated antigens corresponding to class II dimers (30,000 and 32,000 Daltons). Comparison with antigens precipitated from horse lymphocyte lysates using (cross-reacting) antibodies to human class I and class II MHC molecules confirmed the results obtained.

Animals↗
PubMed1988

Restriction fragment length polymorphisms of horse class II MHC genes observed using various human alpha- and beta-chain cDNA probes.

Genomic DNA isolated from 20 horses was digested with up to six restriction endonucleases and subjected to southern blot hybridization analysis using various human class II alpha- and beta-chain cDNA probes. A high degree of restriction fragment length polymorphism (RFLP) was found for the DQ alpha, DP beta, DQ beta and DR beta probes, about 20 polymorphic bands being detected for each. DR alpha showed 2-4 polymorphic bands, whereas no evidence for DP alpha-like genes was found. A number of correlations of RFLPs with individual alloantisera were apparent.

Animals↗
PubMed1987

Rapid data acquisition from a microtiter plate fluorescence reader and applications in kinetic measurements.

Programs written in Applesoft BASIC for the rapid acquisition and evaluation of data from a commercially available microtiter plate fluorescence reader are presented. Using the data acquisition program, the relative fluorescence readings from all 96 wells of the microtiter plate (one read cycle of the fluorescence reader) can be stored in each of up to 90 consecutively numbered files on a single-sided diskette. A simple timer circuit is described which, when used in conjunction with the above program, initiates the fluorescence reading process at preset time intervals, thus making automatic acquisition of data possible. A further program plots the data from consecutive files on the computer monitor and prints a hard copy if required. The feasibility of applying the above system and software to kinetic measurements in enzyme systems is demonstrated using methylumbelliferyl phosphate and an alkaline phosphatase/immunoglobulin conjugate. In addition, its use in following the formation of extracellular hydrogen peroxide by stimulated polymorphonuclear leukocytes using horseradish peroxidase-coupled oxidation of the fluorescent compound 7-hydroxy-6-methoxy-coumarin (scopoletin) is described.

Enzyme-Linked Immunosorbent Assay↗
PubMed1978

Determination of chromium sesquioxide in faeces by a spectrophotometric method.

Chromium sesquioxide Cr2O3, present as a non-absorbable marker in faeces, may be determined spectrophotometrically as chromate ion in aqueous solution after ashing and alkaline fusion. Recovery of this substance is excellent. The method described is simpler, more suited to the clinical laboratory and less hazardous than previously reported methods.

Chromium↗