Binding of HLA antigen-containing liposomes to bacteria

Abstract

Highly purified, detergent-solubilized HLA-A and -B antigens and HLA-D antigens were separately incorporated into liposomes. Deter The major histocompatibility complex (MHC) controls the expression of several types of cell surface glycoproteins that seem to have been highly conserved during evolution. In man, two types of MHC antigens have been distinguished. The HLA-A, -B, and -C antigens are composed of two types of polypeptide chains (1, 2). The larger subunit expresses the particular alloantigenic determinants and is intergrated into the hydrocarbon matrix of the membrane whereas the smaller subunit, 02-microglobulin, is invariant and associated with all known HLA-A, -B, and -C antigens (see refs. 1-4). The HLA-D antigens are also composed of two types of dissimilar polypeptide chains, which are membrane integrated (5).It is now well established that the two classes of transplantation antigen molecules participate in various types of cell-cell interactions, at least among the cells of the immune system (for a review, see ref. 6). Thus, the HLA-A and -B antigens, and their counterparts in other species, are essential in the recognition of foreign antigens (7). The HLA-D antigens and their structural equivalents in the mouse and the guinea pig, the Ta antigens, are needed on the surface of macrophages to allow a proper presentation of foreign antigens to helper T lymphocytes (8). Whether these functions for the HLA-A, -B, and -D antigens are the only ones is far from established.The structural similarity between the HLA-A and -B antigens and the immunoglobulins (3, 4) and the functional requirement for MHC antigens in the physiological activation of T lymphocytes against foreign antigens argues for the idea that the transplantation antigens in some manner can physically interact with foreign substances. To Antisera. The antisera directed against O2-microglobulin and the heavy chains of HLA-A and -B antigen were the same as described (1). The reactivity of the anti-HLA-D antisera has been detailed (9). Fab fragments were prepared from the IgG fractions of the antisera and from normal rabbit IgG (10). The reactivity of all the antisera used could completely be absorbed out with papain-solubilized transplantation antigens. Thus, these antisera did not display measurable reactivity against the intracellular or membrane-integrated portions of the transplantation antigens (unpublished observations).Bacteria. Five bacterial strains obtained as clinical isolates from the routine diagnostic laboratory were used. The strains used were Neisseria catarrhalis § 5 and 807 (NC 5

On the Interaction between β2‐Microglobulin and Group A Streptococci

“…-B, and -C antigens thus seem the most likely participants in an interaction with streptococci. It has previously been reported that liposome-bound HLA antigens interact with strains of Branhatnetta catarrhalis and Haetnophiliis itifluenzae (streptococei were not included in the study), but this interaction seemed to involve the heavy HLA chain rather than /Jim [17], In the present work we found a very close correlation between /i^m binding and HLA binding, and HLA binding was also inhibited by jS^m. Our results favour the conclusion that /5;m in the HLA complex Is able to interact with streptocoecal surfaee structures.…”

Immunologic aspects of liposomes: presentation and processing of liposomal protein and phospholipid antigens

“…Based on enzymatic and serologinjection of carrageenan [59] or liposomes containing a ical data, MHC reconstituted into liposomes was found cytotoxic agent (dichloromethylene diphosphonate) to be at least partly or fully in a 'right side out' [60,611. These treatments resulted in severe suppresconfiguration similar to that found in cells [30,[33][34][35][36][37] [62]. In these experiments sarily excluded.…”

Four Faces of Cell-Surface HLA Class-I: Their Antigenic and Immunogenic Divergence Generating Novel Targets for Vaccines

“…Face-1, Face-2 and Face-3 can be incorporated onto liposomes [138,139] or extra cellular vesicles to be used as vaccines. Klareskog et al [140] have developed a protocol to making HLA-containing liposomes, which would be valuable to develop HLA-liposome vaccines to target the novel faces of HLA. More investigations are needed to fully understand the functional roles of these new faces of HLA-I in human diseases.…”