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R Scollay

Publications and source records attributed to R Scollay.

117 records · Page 7Linked to original sources
PubMed1976

Studies on the lymphocytes of sheep. I. Recirculation of lymphocytes through peripheral lymph nodes and tissues.

Recirculating lymphocytes were collected from the efferent ducts of peripheral somatic nodes and incubated in vitro with 51Cr. After washing, the labeled cells were returned to the sheep by i.v. injection. The partitioning of the labeled cells between blood and efferent (intermediate) lymph, or between efferent and afferent (peripheral) lymph was monitored for the next 24 h by assaying the radioactivity in appropriate samples of cells. The labeled lymphocytes took several hours to migrate through the nodes so that they equilibrated between blood and lymph in about 10 h. This pattern was not altered grossly during the inductive phase of an immune response. The small numbers of lymphocytes which migrated through peripheral tissues entered the lymph at least quickly as those that migrated through lymph nodes.

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PubMed1976

Studies on the lymphocytes of sheep. II. Some properties of cells in various compartments of the recirculating lymphocyte pool.

The proportion of cells bearing surface immunoglobulin (Ig) and the normal lymphocyte transfer (NLT) reactivity of mononuclear cells obtained from the blood, afferent lymph, and efferent lymph from both somatic and intestinal nodes of sheep were measured. The proportion of Ig-positive lymphocytes was approximately 30% in blood and efferent lymph, but only about 10% in afferent lymph. The proportion of unlabeled lymphocytes (T cells) was about the same in all the preparations, as afferent lymph contains 15--20% macrophages. Despite this apparent uniformity in the T cell content, the NLT reactivity of efferent lymph was 3 to 5 times higher than that of blood or afferent lymph. No humoral factors could be detected by incubating cells in the various plasmas in vitro before injection. No inhibitory cells could be detected when mixtures of cell populations were used to initiate lesions. We suggest that lymphocytes in efferent lymph are more reactive than others because they are "groomed" by macrophages during their recirculatory passage through the substance of the node.

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PubMed1975

Differences in the graft-versus-host reactivity of cells migrating through nonlymphoid tissue or lymph nodes.

Normal lymphocyte transfer reactions have been used to test the alloreactivity of lymphocytes which have migrated through lymph nodes (i.e., in efferent lymph) or nonlymphoid tissues (i.e., in afferent lymph) in sheep. Lymphocytes from afferent lymph are much less efficient at inducing a normal lymphocyte transfer lesion than lymphocytes from efferent lymph. Afferent cell preparations (which contain about 10% macrophages) do, however, cause a greater inflammatory response in the early part of the reaction, but this is at least partly nonspecific. A mixture of afferent and efferent cells produces a lesion which is simply the sum of the two expected reactions, suggesting that the afferent lymphocytes are not merely inhibited by a factor or cell in the preparation.

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PubMedDate not supplied

Mouse strain differences in subset distribution and T cell antigen receptor expression among CD4-CD8- thymocytes.

'Double negative' (CD4-CD8-) thymocytes from adult mice of different inbred strains were examined for surface expression of CD3 and of various forms of the T cell antigen receptor (TcR), as well as for the levels of subpopulations defined by the surface markers HSA ('heat stable antigen', recognized by M1/69, J11d and B2A2), CD5 (Ly 1) and Thy 1. Marked variations were found in the level of the double negative subsets which were surface TcR+, or which were HSA-CD5+; these generally varied together since most CD4-CD8-HSA-CD5+ thymocytes were TCR+. The level of the CD3-TCR complex on the surface of those double negative thymocytes which were TcR+ was as high as on mature T cells in some strains (CBA/Ca), but was much lower in other strains (C57BL/6J). In most mouse strains the CD4-CD8-HSA-CD5+ thymocytes expressed predominantly the alpha beta form of the TcR, with an exceptionally high (70%) usage of V beta 8 gene products. In strains which lacked V beta 8 expressing T cells due to a deletion of the V beta 8 gene region, reduced levels of alpha beta TcR+ cells were found within the CD4-CD8- thymocytes; the HSA-CD5+ subset was then only present at low levels (as in SJL/J and C57BR mice) or was present at a high level but expressed predominantly gamma delta TcR (as in SWR mice). The results suggest that the accumulation of CD4-CD8-TcR+ HSA-CD5+ thymocytes is a selective event, and that their developmental pathway is off the mainstream of T cell maturation in the thymus.

Animals↗
PubMedDate not supplied

The expression of murine alloantigens on blood lymphocytes.

Single- and two-colour immunofluorescence was used to analyse and compare the expression of 12 antigens on the surface of Ig- mouse blood lymphocytes (BL) and Ig- lymph node (LN) cells. Studies in different strains of mice showed that: (i) there were fewer Thy-1+, Ly 1+, L3T4+ cells in BL compared to LN; (ii) Ly 2+ BL showed a unique fluorescence profile with a temporal variation in antigen density not evident in LN; (iii) Thy-1- Ly 1- cells were more common in BL than LN; (iv) L3T4 and Ly 2 were present on mutually exclusive subpopulations in BL; (v) Ly 6A, (Ly 6.2), Ly 6C (Ly 28.2) Ly 28.6C and Ly 12.1 antigenic determinants were expressed on the same proportion of BL and LN cells and to the same level; (vi) Ly 24 (Pgp-1) was the only alloantigen examined where the number of positive cells was increased in BL (65%) compared to LN (40%); (vii) Ly 5 and Ly 15 (LFA-1) showed significant differences in antigen density distribution between BL and LN; (viii) Ly 21.2 was similar to Ly 15.2 expression; (ix) 20% of Ig-LN cells were Ia+, but Ia was absent from Ig-BL. Thus, BL differ in antigen distribution and density from lymphocytes in LN and other tissues and should be considered as a unique population of lymphocytes.

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