The Journal of Experimental Medicine

Glimcher, L; Shen, F W; Cantor, H

doi: 10.1084/jem.145.1.1pmid: 187714

We have studied the cell-surface phenotype of natural killer (NK) cells of NZB and B6 mice which react to an MuLV+ lymphoid tumor. (a) NK cells do not express Thy1, Ly2, or Ig surface markers. (b) NK cells express an antigen recognized by C3H anti-CE antiserum ('anti-Ly1.2 antiserum'). Inasmuch as NK activity of spleen cells from B6 and B6/Ly1.1 congenic strains were both equally sensitive to C3H anti-CE antiserum, the NK antigen is distinct from Ly1.2. This point was confirmed by the observation that alphaNK activity was removed by absorption of C3H anti-CE antiserum with spleen cells from either B6 or B6/Ly1.1 congenic strains. Absorption of C3H alphaCE serum with BALB/c thymocytes and spleen cells (which are Ly1.2+NK-) removed anti-Ly1.2 activity and left anti-NK activity intact. This absorption step could be circumvented by inserting the BALB/c genotype into the recipient immunized to CE cells (i.e., (C3H X BALB/c)F1 alphaCE spleen cells). This antiserum, provisionally termed 'anti-NK', defines a new subclass of lymphocytes which may play a central role in the immunosurveillance against tumors.

Huber, B; Gershon, R K; Cantor, H

doi: 10.1084/jem.145.1.10pmid: 299766

CBA/N mice have an X-linked B-cell maturation defect which is reflected in part in an absence or dysfunction of a subclass of mature B cells. We have immunized the defective male offspring of the mating (CBA/N female X BALB/c male) with BALB/c spleen cells. The resulting antiserum (alphaLyb3) selectively reacts with a component on the surface of a portion of B cells from a panel of H-2 different mouse strains. Binding of alphaLyb3 serum to this B-cell subclass results in substantial (10- to 20-fold) enhancement of the antibody response to low doses of SRBC. Both binding and enhancing activity are removed by absorption with B cells from B6 and BALB/c, but not CBA/N mice. Absorption of the serum with bone marrow cells, T cells, or thymocytes from Lyb3+ strains does not remove activity. Since the enhanced plaque-forming cell (PFC) responses are specific for the immunizing antigen, and since no PFC response is produced by injection of the antiserum alone, this enhancement probably reflects a second signal produced by specific interaction between antibody and the surface Lyb3 component. Moreover, this signal can partially replace the requirement for T cells in the production of antibody to a "thymus-dependent" antigen. These findings (taken in conjunction with the previously described immune defects in CBA/N mice and other studies of B-cell maturation) suggest to us that Lyb3 is a cell surface component expressed selectively on a mature B-cell subclass. This component is important in B-cell triggering by antigen and fails to develop in CBA/N mice, due to a dysfunction of a regulatory gene on the CBA/N X chromosome.

Primi, D; Hammarström, L; Smith, C I; Möller, G

doi: 10.1084/jem.145.1.21pmid: 299768

The existence of autoreactive B cells was predicted by theoretical considerations and, recently, confirmed by direct experiments. The aim of the present work was to investigate if the capacity of self-reactive B cells to be activated with different polyclonal B-cell activators (PBA) reflects the heterogeneity of the response as seen in all the Ig-positive cells. We injected mice with dextran sulfate, lipopolysaccharide from Escherichia coli 055:B5, and purified protein derivate of turbercle bacteria RT32 and studied the complement-dependent cytotoxicity against syngeneic spleen cells caused by the sera from injected mice with regard to the different parameters used for characterization of B-cell subpopulations. It was found that the capacity of self-reactive B cells to secrete antibodies reflects the polyclonal-activating capacity of the PBA used. The implications of these findings for the understanding of the triggering mechanism of B lymphocytes and for self-nonself discrimination are discussed.

Hay, J B; Hobbs, B B

doi: 10.1084/jem.145.1.31pmid: 830789

The blood flow to individual lymph nodes of sheep and rabbits has been determined with 85Sr-labeled microspheres. A popliteal node of the sheep received 0.014% of the cardiac output and a comparable node in the rabbit 0.011%. A sheep lymph node weighing 1 g received an average of 24 ml/h of blood. It was calculated that there was a highly selective removal of lymphocytes by the node and that an equivalent to one in every four lymphocytes that entered a normal lymph node migrated out of the blood, through the substance of the node, and into the efferent lymph. During the immune response to either allogeneic lymphocytes or tuberculin, the blood flow to sheep lymph nodes, even without considering the increase in node weight, increased an average of fourfold. During the primary immune response in the rabbit to keyhole limpet hemocyanin, the blood flow increased threefold. The increase in blood flow preceded the antigen-induced increase in lymphocyte traffic recorded in the efferent lymph. The early phase of increased blood flow was considered to be due to hyperemia, whereas the latter phase had a significant angiogenesis component. It was calculated that an equivalent to 60% of the entire mobilizable pool of lymphocytes could pass through an average lymph node in the blood during an immune response lasting 5 days.

Sljivić, V S; Watson, S R

doi: 10.1084/jem.145.1.45pmid: 299769

Splenic and peritoneal macrophages from mice treated with Corynebacterium parvum enhanced the antibody response in vitro of normal nonadherent spleen cells to SRBC, but not to DNP-POL. This enhancement was dependent on the dose and time of administration of C. parvum and could be abrogated by pretreatment with carrageenan. Macrophages from T-cell-depleted mice failed to enhance the response, but this ability was restored if the mice had been reconstituted with purified T lymphocytes. Macrophages that are activated by C. parvum are a resident nondividing population. It is postulated that activated macrophages, capable of enhancing antibody responses to T-cell-dependent antigens, arise through a cell-mediated reaction to C. parvum.

Bernard, O; Ripoche, M A; Bennett, D

doi: 10.1084/jem.145.1.58pmid: 830790

The distribution of maternal immunoglobulins in the mouse uterus and embryo in the days after implantation has been studied on sections incubated with sheep Fab anti-mouse immunoglobulins labeled with peroxidase. At the time of implantation the blastocyst is already surrounded by immunoglobulins that are also present in the blastocoel and early endoderm; uterine glands contain large amounts of immunoglobulins. Later, immunoglobulins are concentrated in the vacuolated endoderm, then the visceral yolk sac and the embryonic gut. They are also present in the various cavities of the embryo. Trophoblast cells progressively contain increasing amounts of immunoglobulins. In the decidua, immunoglobulins coat the cells and also occasionally appear as cytoplasmic granules. The early presence of maternal immunoglobulins may represent the transfer of serum proteins as a means of nutrition for the embryo. It is also very likely to have an immunological significance in the protection of the embryo.

Sherman, L A; Lee, J

doi: 10.1084/jem.145.1.76pmid: 830791

Guinea pig peritoneal macrophages were demonstrated to bind selectively soluble 125I-fibrin and fibrin/fibrinogen complexes as compared with fibrinogen, fibrinogen degradation products, and fibrin degradation products. Cellular uptake was considered to be surface receptor binding on the basis of removal of bound 125I-fibrin by trypsin and because uptake occurred in the presence of metabolic inhibitors. 125I-fibrin uptake could be blocked by nonradioactive fibrin but not by IgG or immune complexes. Binding was uneffected by prior treatment with plasmin or trypsin but was calcium dependent. Only limited reversibility of binding could be demonstrated after prolonged incubation. Scatchard plots permitted an estimate of the number of bound molecules. At saturation 6.92 X 10(6) 125I-fibrin molecules were bound per cell. Similar binding of fibrin was noted in polymorphonuclear leukocytes, but not lymphocytes or fibroblasts. Soluble fibrin binding may be a host defense mechanism whereby the reticuloendothelial system can remove fibrin from the blood before the development of microthrombi.

Takahashi, M; Tack, B F; Nussenzweig, V

doi: 10.1084/jem.145.1.86pmid: 830792

During the solubilization of immune precipitates BSA-rabbit antibodies to BSA by human complement, at least three stages can be distinguished. (A) Generation of alternative pathway C3-convertase sites associated with the immune complexes. During the first minutes of interaction between the immune aggregates and serum, before any solubilization has taken place, properdin (P), factor B, and C3 moieties are incorporated into the lattice. The washed precipitates have C3-convertase activity, which can be completely inhibited by antibodies to factor B, but not to C2. The assembly of the convertase is temperature-dependent, and does not take place in the absence of Mg++. The immune complex-associated C3-convertase activity decays rapidly at 37 degrees C, but it can be restored by addition of purified factor B and properdin. (B) Amplification. When the aggregates bearing C3-convertase are incubated with purified C3, solubilization takes place. It appears that solubilization is caused by the accumulation of a large number of C3 fragments on the Ag-Ab lattice. In solubilized complexes, the molar ratios of Ab/C3 are close to one. (C) Spontaneous release. The final step in the solubilization process is a secondary reaction, during which some rearrangement of the lattice takes place. It occurs in medium devoid of serum and does not require divalent cations.

Ahmed, A; Scher, I; Sharrow, S O; Smith, A H; Paul, W E; Sachs, D H; Sell, K W

doi: 10.1084/jem.145.1.101pmid: 299767

CBA/N mice and F1 male mice, which are hemizygous for the CBA/N X chromosome, have an immune defect which is associated with the absence (deficiency) of a subpopulation of mature or late developing B lymphocytes. This characteristic was utilized to develop an antiserum that was specific for this subclass of B cells. C57BL/L mice were immunized with DBA/2 spleen calls, and the resulting antisera was absorbed with lymphoid cells derived from immunologically abnormal (CBA/N female X DBA/2 male)F1 male mice. The absorbed antisera was cytotoxic for a subpopulation of lymphocytes that was present in the spleens of adult DBA/2 and (CBA/N female X DBA/2 male)F1 female mice. The cells killed by the absorbed antisera were Ig-bearing, complement receptor-bearing B lymphocytes, which had a low-to-intermediate density of total surface Ig. Moreover, the cells remaining after treatment of adult (CBA/N female X DBA/2 male)F1 female spleen cells with the absorbed antisera and C had a high ratio of surface IgM to IgD. The development of this cytotoxic alloantisera, which is specific for a late developing (mature) subpopulation of B lymphocytes, will allow the functional characterization of subclasses of B lymphocytes.

Berzofsky, J A; Schechter, A N; Shearer, G M; Sachs, D H

doi: 10.1084/jem.145.1.111pmid: 830786

The progression of the Ir gene-controlled antibody response to staphylococcal nuclease in mice with repeated immunizations has been examined. H-2-linked control of the response to a single immunization with 100 mug of nuclease in complete Freund's adjuvant was confirmed. However, among strains of the high responder H-2a haplotype, the response of the A/J mice was about 10-fold higher than that of the B10.A, indicating additional non-H-2-linked control. In addition, the low responder C57BL/10 (H-2b) strain produced antibody levels as high as or higher than those of the congenic high responder B10.A (H-2a) strain when both strains were repeatedly immunized, indicating complexity even in the H-2-linked control of the response to this small monomeric protein. Polypeptide fragments of nuclease were also studied as immunogens. The antibody response to one fragment (residues 99-149) was found to follow the same pattern among five strains tested as that to whole nuclease. However, in this case the C57BL/10 was found to be a nonresponder rather than a low responder, failing to develop a response despite repeated immunizations. In contrast, the C57BL/10 showed a low but significant response to another fragment (residues 1-126) of nuclease. These results suggest that the apparent H-2-linked control of the response to whole nuclease is a reflection of the ability to recognize a determinant(s) in the region from residues 99 to 149, and that the eventual response of the C57BL/10 strain after hyperimmunization reflects the recognition of other determinants. If these observations reflect the common recognition of a determinant on native nuclease and on a random-conformation fragment, they have implications about the conformational specificity of the receptors, or the flexibility of the determinants, involved in H-2-linked Ir-gene control. In addition, evidence is presented for a possible second H-2-linked gene (or genes) controlling the response to other determinants of nuclease expressed on the polypeptide fragments.