Zeitschrift für Immunit?tsforschung: Immunobiology最新文献

The sera of patients with pigeon breeders' disease usually contain precipitating serum factors as well as human complement consuming factors as shown by incubation of the serum with pigeon dropping antigens. Although a single serum factor, possibly an IgG antibody, might account for both phenomena, affinity chromatography experiments revealed that the sera of patients with pigeon breeders' disease contain non-precipitating, human complement consuming, serum factors besides precipitating serum factors which are also capable of complement consumption. The non-precipitating serum factors most likely belong to the IgG3 immunoglobulin subclass, whereas the precipitating antibodies belong to the subclasses IgG₁ and IgG₂.

BASILEA rabbits lack the expression of ϰ-polypeptide chains and compensate for this lack with expression of A. polypeptide light chains. These rabbits were immunized with streptococcal group A-variant vaccines. The heterogeneity of the λ polypeptide chains of specific antibodies was analyzed and compared with that of ϰ light chains. No significant difference was found by SDS-PAGE and IEF in the number of light chain bands of high affinity antibody expressed. This suggests that in the rabbit the size of the variable region repertoire is similar for

λ and ϰ light chains.

Cytotoxic T lymphocytes (CTL) from DBA/2 strain mice primed with Sendai virus (SV) in vivo were activated by secondary stimulation of spleen cells with viral antigens in vitro and analyzed for their target antigen specificity. These effector cells lysed syngeneic Sendai virus infected target cells, marginally a variety of non-infected targets and had a strong cytotoxic effect on H-2b targets. Studies on the antigenic requirements revealed that all SV preparations which generated specific CTL also induced the alloreactive populations. Similar results were found in the response to Newcastle disease virus (NDV) and some influenza A viruses; all these viruses were mitogenic for lymphocytes. Experiments on the cellular requirements indicated that virus specific and alloreactive cells can be separated by their requirements for help and for restimulation. By competition experiments both activities could be attributed to clearly separable T cell subpopulations. The induction mechanism of alloreactive T cells by viral antigens is discussed.

Lyt T cell subsets involved in the generation of H-2 restricted and alloreactive cytotoxic effector cells were analysed using anti Lyt antisera. Our data show that Lyt 1, 2, 3 + T cells are required for the induction of primary and secondary H-2 restricted and TNP-specific killer cells. In contrast, primary and secondary H-2 restricted and virus-specific T effector cells were obtained from selected Lyt 2, 3 + T cell populations and were not dependent on the presence of Lyt 1, 2, 3+ T cells. Allogeneic responses to selected K, I, or D region differences were obtained only in the presence of Lyt 1,2,3 + T cells; yet alloreactive killer cells were effectively generated from selected Lyt 2,3+ T cell populations deprived of Lyt 1,2,3+ T cells, when responder and stimulator cells differed at either K + D, K + I, I and D regions or in the entire H-2 region.

Taken together, the results suggest that there is no qualitative difference between alloreactive and H-2 restricted cytotoxic responses in their requirements for particular Lyt T cell subsets. The findings indicate that the number of different antigenic determinants rather than their association with MHC self determinants is critical for the requirement of Lyt 1, 2, 3+ T cells during the sensitization phase.

While evaluating herpes simplex virus (HSV) typing by indirect immunofluorescence staining, an undesired specific staining pattern turned out to be a reliable marker for herpes simplex type 1. Cells infected with herpes simplex type 1 displayed clear staining with a FITC-conjugated antiglobulin preparation, also in the absence of herpes simplex-specific antibodies. Using the same conjugate, herpes simplex type 2-infected cells exhibited no fluorescence. The particular type of staining observed was influenced by neither the anatomical site of origin of the virus isolate nor the cell type used for virus preparation. Herpes simplex type 1-specific fluorescence was only obtained with the use of FITC-conjugates possessing anti-IgG activity. Both reliability and specificity of this discriminating procedure as a diagnostic tool has been established by typing 282 virus isolates over a period of 4 years.

A new procedure for the isolation of the human complement component C9 is described. This procedure offers the possibility to prepare functionally pure C9 in a one-step procedure with a high recovery of 10–22% of the biological activity. The ¹²⁵iodinated C9 had a molecular weight of 78,000 daltons and was only contaminated in traces with other proteins. Further purification by absorption with an «anti-impurity» column lead to a C9 preparation which behaved as a homogenous single polypeptide chain in SDS polyacrylamide gel electrophoresis after reduction with mercaptoethanol. It formed a single bell-shaped precipitate in crossed immunoelectrophoresis with antibodies against human serum in the gel of the second dimension. The recovery of the biological activity after the second purification step was in the order of 6–10%. Both preparative steps could be performed within a few hours. 450 μg C9 protein were isolated from 135 ml human serum. A human serum completely defective in C9 was prepared by the extensive absorption of a smaller volume of human serum proteins with the anti-C9 column.

Protein I from the outer membrane of Escherichia coli is a B-lymphocyte mitogen in mice. Polyclonal activation of mouse splenocytes was demonstrated by ³H-thymidine incorporation into DNA, ³H-uridine incorporation into RNA, and by a hemolytic plaque assay in three inbred mouse strains. B-lymphocytes from LPS responder mice (C57B1/10, STU/nu/nu) and LPS non-responder mice (C3H/HeJ) both responded well to protein I. The presence of serum was not necessary for mitogenicity; bovine serum albumin exhibited a beneficial effect on serum-depleted cultures. Thymocytes of C3H/HeJ mice were not activated by protein I. Protein II* from E. coli was also tested in our systems and showed a weak B-lymphocyte stimulatory activity. Human peripheral blood lymphocytes were not activated.