Lymphocyte Culture: Induction of Colonies by Conditioned Medium from Human Lymphoid Cell Lines

It has been shown that macrophage and granulocyte colonies can be induced m semisolid agar (1-3) in the presence of substances termed colony-stimulating factors (CSF), which are released predominantly by monocytes (4). However, attempts to induce formation of lymphoid colonies with CSF have so far proved unsuccessful. In the mouse, B lymphoid colonies are formed in the presence of 2-mercaptoethanol (5), and T lymphoid colonies can be induced with the plant lectins phytohemagglutinin (PHA) and concanavalin A (6). T lymphoid colonies can also be established from human peripheral blood lymphocytes in the presence of PHA (7-9), whereas with pokeweed mitogen mixed T and B lymphoid colonies are formed (9). Established human lymphoid cell lines multiply spontaneously in the absence of plant lectins or mercaptoethanol, and it seemed possible that such cells might release growth-stimulating substances into the culture medium. We have therefore investigated the ability of conditioned medium (CM) obtained from lymphoid cell lines to induce normal human peripheral blood lymphocytes (PBL) to form lymphoid colonies in agar

Immunoglobulin G Heavy Chain (Gm) Allotypes in Multiple Sclerosis

Serum samples from 70 Caucasian patients with multiple sclerosis were typed for nine Gm markers. Significant association was found with the Gm 1,17;21 phenotype, and the relative risk for individuals with this phenotype was calculated at 3.6. The data indicate that Caucasians positive for Gm 1,17;21 are almost four times more likely to develop multiple sclerosis than those without this phenotype

Immunoglobulin Allotypes and Immune Response to Meningococcal Group B Polysaccharide

Serum samples were collected from 120 healthy adult volunteers (105 Caucasians and 15 Negros) before and after immunization with meningococcal polysaccharide (MPS) group B vaccine. Antibodies to MPS group B were measured and sera were typed for several Gm and Km(l) allotypes. A significant association was found between the Km(l) allotype and immune response to MPS group B in Caucasians

Heterozygosity at Gm Loci Associated with Humoral Immunity to Osteosarcoma

Familial clustering of osteosarcoma suggests the involvement of genetic factors (1, 2), and the demonstration of a high incidence of osteosarcoma-specific antibodies (3, 4), as well as tumor-specific cell-mediated immunity (5) in patients and their relatives, indicates the involvement of immunological factors in the pathogenesis of this disease. Certain Gm allotypes (genetic markers of IgG) have been shown to be associated with a high relative risk of some forms of cancer. For instance, in Caucasians an unusual Gm haplotype--Gm 1,3;5,13,14--has been found to be associated with neuroblastoma (6), and an increased frequency of Gm (2) has been reported in patients with malignant melanoma (7, 8). A recent report has shown an association of the Gm 1,2; 13,15,16,21 phenotype with lung cancer and primary hepatoma in the Japanese (9). To our knowledge, however, the possible role of Gm allotypes in predisposition to osteosarcoma has not been examined. Immune responsiveness to a variety of antigens in both experimental animals and humans has been shown to be controlled either by major histocompatibility complex (MHC)-linked immune response (Ir) genes or by allotype-linked Ir genes (10-13). In some instances an interactive effect of these two unlinked genetic systems has been observed (12). It is possible that MHC-linked or allotype-linked Ir genes may also influence humoral immunity to tumor antigens. In this report we present evidence for complementary Ir genes controlling immune responses to osteosarcoma-associated antigens (OSAA)

Fractionation and Characterization of the Immunosuppressive Substance in Crude Extracellular Products Released by Streptococcus intermedius

The noncytotoxic immunosuppressive substance detected in crude extracellular products of Streptococcus intermedius (CEP-Si) was fractionated by two steps of preparative isoelectric focusing in sucrose gradients using ampholytes of pH range from 3.5 to 6 and 4 to 5, respectively. The in vitro and in vivo suppressor effects of the most highly purified fraction of CEP-Si, designated fraction 3\u27 (F3\u27EP-Si), corresponded well with those of the original CEP-Si. F3\u27EP-Si was sensitive to the effects of alpha, gamma, and delta chymotrypsin, trypsin, and heating. It contained ~ 1% of the total amount of protein found in the original CEP-Si, corresponding to a single band on analytical isoelectric focusing, stainable by Coomassie Blue and of isoelectric point of 4.25. The absorption spectrum of F3\u27EP-Si had a maximum at 260 nm but its biological activity was resistant to deoxyribonuclease and ribonuclease A and it did not contain material stainable by methylene blue. It was also resistant to neuraminidase and did not contain material stainable by periodic acid Schiff. We conclude that the substance responsible for the suppressor activity of CEP-Si is a protein of molecular weight ~90,000, which adheres to Sephadex or cellulose acetate and forms complexes with other, nonactive constituents of CEP-Si