GENETIC CONTROL OF BONE MARROW GRAFT REJECTION : I. DETERMINANT-SPECIFIC DIFFERENCE OF REACTIVITY IN TWO PAIRS OF INBRED MOUSE STRAINS

Transplantation of 5 x 105 DBA/2 (H-2d) bone marrow cells into irradiated B10 and 129-strain mice (both H-2b) resulted in graft failure in the first recipient strain and in graft take in the second. Transplantation of B10 (H-2b) cells into irradiated B10.BR and C3H mice (both H-2k) also resulted in failure in the congenic B10.BR recipients and take in the C3H mice. Resistance and susceptibility of B10 and 129-strain animals were specific for given H-2 alleles of donor cells. Transplantation of DBA/2 marrow into (B10 x 129)F2 mice and of B10 marrow into (B10.BR x C3H)F1 x C3H backcross mice revealed definite genetic control of the graft-rejection process, presumably at the level of alloantigen recognition. Resistance to allografts, or responder status, was conferred upon segregating mice by dominant alleles of two major independent autosomal loci. The effects of the loci were additive. Conversely, susceptibility to allografts, or nonresponder status, was due to the apparently recessive alleles of both loci. None of the genes was closely linked with the markers tf (tufted) and T (brachyury) of linkage group IX, Aw (white-bellied agouti) of linkage group V, Sl (steel) of linkage group IV, and cch (chinchilla) and p (pink eye, dilute) of linkage group I. There were suggestions, however, that the regulator genes of marrow graft rejection are either non-H-2 histocompatibility genes or other genetic factors closely linked with them

PECULIAR IMMUNOBIOLOGY OF BONE MARROW ALLOGRAFTS : I. GRAFT REJECTION BY IRRADIATED RESPONDER MICE

Mice are capable of rejecting H-2-incompatible bone marrow grafts after a single lethal exposure to X-rays. The onset of rejection begins 18–24 hr after transplantation and is completed by 96 hr. Maturation of this type of allograft reactivity does not occur until the 22nd day of life. In adult mice, the resistance to marrow allografts can be weakened by administration of cyclophosphamide or dead cultures of Corynebacterium parvum, but not heterologous anti-thymocyte serum. Sublethal exposures to X-rays 7 or 14 days before transplantation also weaken resistance. There is considerable interstrain variation in the ability of mice to resist allografts, even when H-2 differences between hosts and donor are kept identical. Although H-2 incompatibility is a necessary prerequisite for resistance, additional genetic factors influence the outcome of marrow allografts, presumably by controlling recognition. The regulator genes are determinant specific and the alleles for resistance or responder status appear to be dominant. The responder phenotype is expressed by hemopoietic cells and not by the environment. Accordingly, resistance is conferred to otherwise susceptible mice upon transfer of bone marrow cells but not of serum. The production and differentiation of effector cells for marrow graft rejection are thymus independent. In conclusion, bone marrow allografts elicit a particular transplantation reaction, previously unknown, in irradiated mice. Peculiar features of this reaction are the lack of proliferation of host lymphoid cells, tissue specificity, thymus independence, and regulation by genetic factors which apparently do not affect the fate of other grafts

CELLULAR DIFFERENTIATION OF THE IMMUNE SYSTEM OF MICE : III. SEPARATE ANTIGEN-SENSITIVE UNITS FOR DIFFERENT TYPES OF ANTI-SHEEP IMMUNOCYTES FORMED BY MARROW-THYMUS CELL MIXTURES

Marrow cell suspensions of unprimed donor mice have been transplanted into X-irradiated syngeneic hosts. 5–46 days later, bone cavities and spleens contained regenerated cells of the immune system which required interaction with thymocytes (from intact donors) and antigen (SRBC) to form antigen-sensitive units (ASU) and to generate mature immunocytes. These cells were capable of differentiating either into direct or indirect hemolytic plaque-forming cells (PFC). The precursors of PFC regenerated earlier than the other cell type necessary for immunocompetence, the antigen-reactive cell (ARC). The latter was not found until 10 or more days after transplantation. Availability of ARC was inferred from PFC responses elicited by grafted mice challenged with SRBC at varying intervals. In a second series of experiments, graded numbers of marrow cells (ranging from 107 to 5 x 107) were transplanted with 5 x 107 or 108 thymocytes into irradiated mice, and SRBC were given 18 hr later. After 9–12 days the recipient spleens contained all or some of the following immunocytes: direct and indirect PFC, and hemagglutinating cluster-forming cells. The frequency of each immune response varied independently of the others, but in relation to the number of marrow cells grafted. This was interpreted to indicate that ASU formed in irradiated mice by interaction of marrow and thymus cells were similar to those of intact mice. In particular, they were specialized for the molecular class (IgM or IgG) and function (lysis or agglutination) of the antibody to be secreted by their descendent immunocytes. Hence, class-differentiation appeared to be conferred upon ASU by their marrow-derived components

DISTINCT EVENTS IN THE IMMUNE RESPONSE ELICITED BY TRANSFERRED MARROW AND THYMUS CELLS : I. ANTIGEN REQUIREMENTS AND PROLIFERATION OF THYMIC ANTIGEN-REACTIVE CELLS

Marrow cells and thymocytes of unprimed donor mice were transplanted separately into X-irradiated syngeneic hosts, with or without sheep erythrocytes (SRBC). Antigen-dependent changes in number or function of potentially immunocompetent cells were assessed by retransplantation of thymus-derived cells with fresh bone marrow cells and SRBC; of marrow-derived cells with fresh thymocytes and SRBC; and of thymus-derived with marrow-derived cells and SRBC. Plaque-forming cells (PFC) of the direct (IgM) and indirect (IgG) classes were enumerated in spleens of secondary host mice at the time of peak responses. By using this two-step design, it was shown (a) that thymus, but not bone marrow, contained antigen-reactive cells (ARC) capable of initiating the immune response to SRBC (first step), and (b) that the same antigen complex that activated thymic ARC was required for the subsequent interaction between thymus-derived and marrow cells and/or for PFC production (second step). Thymic ARC separated from marrow cells but exposed to SRBC proliferated and generated specific inducer cells. These were the cells that interacted with marrow precursors of PFC to form the elementary units for plaque responses to SRBC, i.e. the class- and specificity-restricted antigen-sensitive units. It was estimated that each ARC generated 80–800 inducer cells in 4 days by way of a minimum of 6–10 cell divisions. On the basis of the available evidence, a simple model was outlined for cellular events in the immune response to SRBC

Profound Muscle Weakness and Pain after One Dose of Actonel

The World Health Organization (WHO) defines osteopenia as a bone density between 1 and 2.5 standard deviation (SD) below the bone density of a normal young adult Iqbal 2000. Osteoporosis is defined as 2.5 SD or more below that reference point Iqbal 2000. Bisphosphonates are a group of medications used to treat osteoporosis, Padget's disease of bone, and osteopenia. We report a woman who developed profound muscle weakness and pain after one dose of Risedronate (Actonel)

ANTIGEN-SPECIFIC CELLS IN MOUSE BONE MARROW : II. FLUCTUATION OF THE NUMBER AND POTENTIAL OF IMMUNOCYTE PRECURSORS AFTER IMMUNIZATION

Quantitative and qualitative changes of mouse bone marrow cells were studied by limiting dilution assays 2–3.5 months after immunization of donors with sheep erythrocytes or unrelated antigens (Salmonella typhimurium, horse and chicken erythrocytes). Irradiated (C3H x C57BL/10)F1 mice were reconstituted with an excess of nonprimed thymocytes and small graded numbers of primed bone marrow cells. Direct and indirect plaque-forming cells (PFC) were induced by secondary stimulation with SRBC and enumerated on the 9th day after cell transplantation. Marrow precursors of PFC (P-PFC) cooperated with thymocytes in the production of direct and indirect PFC after SRBC priming. The limiting dilution plots, which were not compatible with predictions of the Poisson model before immunization, changed and conformed to this model afterwards, as if the population of P-PFC had become functionally more homogeneous. The concentration of marrow P-PFC increased up to the 3rd month after priming, and decreased during the 4th, varying over two logarithms of nucleated marrow cells. The fluctuation was simultaneous and of the same order of magnitude for precursors of direct and indirect PFC, which were class restricted. A third effect of immunization was detected at 3.5 months: individual precursor units generated 3–4 times more direct and indirect PFC than at earlier intervals. Qualitative and quantitative changes of marrow P-PFC participating in anti-sheep responses were specific, since antigens unrelated to SRBC failed to induce them. The data suggested that marrow-derived cells were the major carriers of immunologic memory, but that they functioned in cooperation with thymus-derived inducer cells during secondary anti-sheep responses

CELLULAR DIFFERENTIATION OF THE IMMUNE SYSTEM OF MICE : VI. STRAIN DIFFERENCES IN CLASS DIFFERENTIATION AND OTHER PROPERTIES OF MARROW CELLS

Marrow cells and 5 x 107 thymocytes of unprimed (C57BL/6 x DBA/2)F1, (C57BL/10 x WB)F1 and (C3H x C57BL)F1 donor mice were mixed in vitro and transplanted into X-irradiated syngeneic hosts. Upon injection of sheep erythrocytes, splenic plaque-forming cells (PFC) secreting IgM (direct PFC or IgG (indirect PFC) hemolytic antibody were enumerated at the time of peak responses. By grading the numbers of marrow cells, inocula were found that contained few immunocompetent cells reaching the recipient spleens, interacting with thymocytes or other accessory cells (or both), and generating PFC. The frequency of responses in BDF1 mice conformed to Poisson statistics, indicating that immunocompetent marrow cells participated in a single-hit interaction limiting PFC responses. The marrow cells assayed were not restricted for the antibody class (IgM versus IgG) to be secreted by mature PFC. Unrestricted marrow cells could have been either the precursors of PFC or accessory cells. Different results were obtained in BWF1 and C3BF1 mice. The frequency of responses in relation to the number of marrow cells grafted did not follow Poisson statistics, and the limiting cells were restricted for antibody class. Presumably, immunocompetent cells of these strains were more heterogeneous than those of BDF1 mice and participated in a multiplicity of cell-to-cell interactions. The strain differences reflected inherent properties of marrow cells and not influences of the environment in which PFC were produced. The results confirmed for bone marrow the heterogeneity of immunocompetent cells reported by others for spleen, and suggested that genetic factors such as "immune response" genes regulate cellular differentiation also for functions other than those related to antibody specificity

EVIDENCE FOR TRANSFORMATION OF SPLEEN CELLS ONE DAY AFTER INFECTION OF MICE WITH FRIEND LEUKEMIA VIRUS : AUTONOMOUS GROWTH POTENTIAL AND EXPRESSION OF HYBRID-RESISTANCE GENES

Proliferation and erythroid differentiation of transplanted DBA/2 marrow cells and Friend virus-induced leukemic cells were assessed in syngeneic, allogeneic (H-2 compatible), and (BALB/c x DBA/2)F1 hybrid mice (CDF1). Measurements were made 5 days after transplantation of donor cells into nonirradiated or X-irradiated mice by the spleen colony or the 125IUdR-59Fe uptake methods. Growth of DBA/2J (Jackson subline) marrow grafts was poor in irradiated CDF1J hybrids as compared with growth in syngeneic and allogeneic hosts. The DBA/2J transplants proliferated, however, without impairment in irradiated CDF1 hybrids which were the progeny of DBA/2 male parents of other sublines, e.g. DBA/2Ha, DBA/2Cr, and DBA/2Cum. In contrast, tissue-cultured Friend leukemic cells of DBA/2J origin grew deficiently in all CDF1 hybrids tested, regardless of irradiation and of the DBA/2 parent's subline. The growth pattern of transplanted DBA/2J cells was a manifestation of hybrid resistance. The results with DBA/2J and other DBA/2 subline grafts suggested that hybrid histocompatibility alleles were expressed to a greater extent in leukemic than in normal marrow cells, for the former were consistently recognized as "nonself" by CDF1 mice, but not the latter cells. The property of deficient growth in irradiated CDF1Ha hybrids was acquired by DBA/2J hemopoietic cells within 6 hr from infection in vivo with Friend leukemia virus, and persisted during the following 8 days. It was ascribed to enhanced expression of hybrid histocompatibility gene(s) (Hh) induced by the virus. Autonomous growth potential of hemopoietic cells, manifested by proliferation in nonirradiated recipients, was first detected 24 hr from infection, and likewise persisted at the later intervals. At the same time, the infected cells grew deficiently also in nonirradiated CDF1Ha mice. The two irreversible cellular changes were regarded as the earliest signals of virus-induced transformation