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Showing papers on "Typing published in 1969"


Journal ArticleDOI
TL;DR: Further experience of the typing of strains of Pseudomonas pyocyanea by their production of pyocines has confirmed the value ofpyocine typing for epidemiological studies and suggests that the occurrence of more than one pyocine type or subtype of Ps.
Abstract: Summary Further experience of the typing of strains of Pseudomonas pyocyanea (Ps. aeruginosa) by their production of pyocines has confirmed the value of pyocine typing for epidemiological studies. The introduction of five new indicator strains has made it possible to distinguish eight subtypes of the commonly occurring pyocine type 1. The subtyping of the type-1 strains shows the same dependence on use of the correct temperature and duration of incubation of the producer strain as does the main typing procedure. In studies of the reliability of the typing and subtyping methods for epidemiological purposes it was noted that not all strains of Ps. pyocyanea isolated from the same site in the same patient were of the same pyocine type or subtype. When several colonies of Ps. pyocyanea from individual diagnostic plates were typed it was found that more than one pyocine type or subtype was more frequently present in the same lesion in patients in hospital than in patients being treated at home. This finding suggests that the occurrence of more than one pyocine type or subtype of Ps. pyocyanea in a patient is generally due to his having been separately infected with strains of more than one type, rather than to instability of pyocine production in a single infecting strain.

122 citations



Journal ArticleDOI
TL;DR: It is concluded that skin grafting and leucocyte injections is a simple and efficient method for production of HL‐A typing antisera of desired specificity, and the results indicate that the remaining alleles of the HL-A system may be identified by antisers obtained by this method.
Abstract: Summary. Eight skin graft donor‐recipient pairs were selected by lymphocyte typing for production of HL‐A typing antisera. After the second or third skin graft from the same donor, antibodies appeared in the sera of five of the recipients. The antibodies were directed against antigens which seem to be determined by alleles of the LA and 4 sub‐loci, and the specificity showed close correlation to the HL‐A incompatibility between donor and recipient. By re‐immunization with intradermal leucocyte injections, two additional recipients produced antibodies against donor cells. One of these antisera seemed to detect a new HL‐A antigen of the 4 sub‐locus (called FJH). It is concluded that skin grafting and leucocyte injections is a simple and efficient method for production of HL‐A typing antisera of desired specificity. The results also indicate that the remaining alleles of the HL‐A system may be identified by antisera obtained by this method.

23 citations


Journal ArticleDOI
TL;DR: The results support the concept that significant quantitative differences in the expression of isoantigens exist among different cell types.
Abstract: SUMMARY The immune adherence technique was modified to permit a direct comparison between the reactivity of lymphocytes and kidney cells from the same person. These two cells were typed using 17 well characterized antisera. There were 82 significant discrepancies from a total of 234 direct comparisons. Absorptions with the negatively reacting cell resulted in diminished or absent serological activity against the positive cell type. The results support the concept that significant quantitative differences in the expression of isoantigens exist among different cell types.

14 citations






Journal ArticleDOI
TL;DR: No change in the results of typing were found, even within 5 min of transfusion, in 22 of these 25 studies, providing a strong argument in favour of the use of a cytotoxic technique for leukocyte typing in renal transplantation, where recipients and cadaver donors often have received blood transfusions before typing.
Abstract: The reproducibility of leukocyte typing by a microdroplet lymphocytotoxicity test was studied in 25 patients after blood transfusions of 1.5–6 litres. No change in the results of typing were found, even within 5 min of transfusion, in 22 of these 25 studies. This contrasts markedly with typing by leukoagglutination where prior transfusions can significantly falsify results. This provides a strong argument in favour of the use of a cytotoxic technique for leukocyte typing in renal transplantation, where recipients and cadaver donors often have received blood transfusions before typing.

3 citations



Journal ArticleDOI
TL;DR: Staphylococcus aureus phages of serological groups A, B and C could be distinguished by the size of their plaques and electron microscopy revealed that the phage of group A differed in the lengths of their heads and tails.
Abstract: Staphylococcus aureus phages of serological groups A, B and C could be distinguished by the size of their plaques. Electron microscopy revealed that the phages of group A differed in the lengths of their heads and tails from those of groups B and C. The terminal knob of each of the phages appeared to be a hexagonal base plate with short spikes. In group B and C phages the base plate was presumably connected to the tail by a conical middle piece.

Journal ArticleDOI
TL;DR: In this paper, a comparison of leucocyte-group differences and lymphocyte-transformation rates in mixed lymphocyte cultures was made, where group differences were present the mean numbers were 3·6 among sibling pairs, 2·4 among parent-child pairs, and 4·7 among unrelated pairs: the corresponding transformation-rates were 9·8, 10·1%, and 15·3%.
Abstract: Blood from 140 pairs (siblings, parent/ child, or unrelated) has been used in a comparison of leucocyte-group differences and lymphocyte-transformation rates in mixed lymphocyte cultures. Where group differences were present the mean numbers were 3·6 among sibling pairs, 2·4 among parent-child pairs, and 4·7 among unrelated pairs: the corresponding transformation-rates were 9·8%, 10·1%, and 15·3%. There was no clear correlation between the number of group differences detected on leucocyte typing and the ability of cells in mixed lymphocyte culture to transform. Leucocyte typing has proved helpful in predicting the outcome of transplants between related people, but these results suggest that this form of typing may be insufficient when donor and recipient are not related.

Journal Article
TL;DR: There is now convincing proof that human leucocyte antigens are transplantation antigen which are capable of influencing the function and survival of kidney transplant, and it is becoming almost universally accepted that matching of donor and recipient in terms of their leucocytes is desirable.
Abstract: At the out et two firm statements can be made: firstly, there is now convincing proof that human leucocyte antigens are transplantation antigens which are capable of influencing the function and survival of kidney transplant; secondly, it is becoming almost universally accepted tbat matching of donor and recipient in terms of their leucocyte antigens is desirable. There is, however, uncertainty in many quarters as to just how desirable, or necessary, prospective leucocyte antigen typing is in clinical practice; and if it is done, to what extent it must be taken into con ideration before embarking on a transplant. The current value of leucocyte typing in transplantation practice is best assessed by reviewing the accumulated evidence which established a correlation between the degree of leucocyte antigen matching of donor-recipient pairs and the outcome of their renal transplants. When doing so, it is as well to bear in mind the many reservations expressed in these reports by the investigators themselves. Problems arose from the fact that neither of the two variables under examination, i.e. the degree of rejection and the degree of histocompatibility, was easy to measure. Clinical assessment of the uccess of tran planta-