Infectious mononucleosis: immunoglobulin synthesis by cell lines

Immunoglobulin synthesis by 16 long-term suspension cultures of mononuclear cells derived from peripheral blood of nine patients with heterophile-positive infectious mononucleosis (IM) has been demonstrated by radioimmunoelectrophoretic techniques. All cell lines synthesized molecules with IgG (γ) heavy chain specificity. 14 cell lines produced molecules with IgM (μ) heavy chain specificity and 11 cell lines produced molecules with IgA (α) heavy chain specificity. No detectable synthesis of molecules with IgD (δ) heavy chain specificity was observed by these cell lines derived from peripheral blood of patients with IM. 13 cell lines produced molecules with type K (κ) light chain specificity and 6 cell lines produced molecules with type L (λ) light chain specificity. Of interest, 9 of 16 lines produced IgG (γ), IgA (α), and IgM (μ) heavy chain molecules and 5 of these cell lines produced molecules with type K (κ) and type L (λ) light chain specificity as well. Further characterization by combined polyacrylamide gel filtration, immunodiffusion, and radioautography indicated the presence of newly synthesized immunoglobulin molecules with both heavy and light polypeptide chains in close association as well as free light polypeptide chain synthesis. Investigation of the localization of immunoglobulin in single cells by immunofluorescent techniques revealed that 5-22% of cells in these lines were strongly reactive with a fluorescein isothiocyanate-conjugated rabbit antisera directed against the antigenic determinants of human IgG and cross-reactive with the determinants common to IgA and IgM. No heterophile antibody, heteroagglutinin, or hemolytic antibody could be demonstrated in these cell lines derived from peripheral blood of patients with heterophile-positive infectious mononucleosis

Blast-Like Transformation Induced in Peripheral Blood Lymphocytes by Cellular Injury: A Comparison of Sonication and Phytohemagglutinin

Abstract The effects of sublethal sonication on short-term lymphocyte cultures were determined and compared to effects of phytohemagglutinin on similar cultures. Cells stimulated by sonication or PHA showed similar blastoid alteration, similar subtleties of trypan blue staining during the first three days of culture, and similar lysosomal patterns in the altered cells. However, cells from sonicated cultures did not display DNA or RNA synthesis rates above those seen in control cultures. In addition, trypan blue staining characteristics indicated a temporarily reversible injury in PHA stimulated cells, but not in sonicated cells. These studies support the concept that blast-like transformation of lymphocytes is related to cell damage and possibly to subsequent increase in size and activity of lysosomes.</jats:p

Similarity of Migration Inhibitory Factor(s) Produced by Human Lymphoid Cell Line and Phytohemagglutinin and Tuberculin-Stimulated Human Peripheral Lymphocytes

Abstract The migration inhibitory factor(s) (MIF) derived from the supernatants of an established human lymphoid cell line (PGLC-33H) and from human peripheral lymphocytes stimulated in vitro by phytohemagglutinin (PHA) and tuberculin (PPD) were characterized and compared. Separation of these supernatants by differential ultrafiltration showed peak inhibitory activity for all three in the fraction containing molecules of the size 10,000 to 50,000. Separation by Sephadex gel filtration (G-75) revealed similar elution profiles for these MIF. Peak inhibitory activity eluted between enzyme markers of m.w. 17,000 and 25,000. The MIF activity contained in these supernatants was found to be heat stable (56°C for 30 min) and chymotrypsin sensitive. The MIF derived from human long term lymphoid cell lines appears to be similar to the MIF produced by human peripheral lymphocytes stimulated in vitro by mitogen and antigen.</jats:p

Production and Characterization of Migration Inhibitory Factor(s) (MIF) of Established Lymphoid and Non-Lymphoid Cell Lines

Abstract Lymphoid cells from established human lymphoid suspension cultures migrate in vitro like guinea pig peritoneal macrophages. Used as indicator cells in the capillary migration technique, these cultured cells appear to be more sensitive than guinea pig peritoneal macrophages to migration inhibitory products. Human lymphoid cell line supernatants contain a factor(s) which inhibits the migration of guinea pig peritoneal macrophages and the cultured lymphoid cells. A number of non-lymphoid cell lines including HeLa, human embryonic lung, rat thymus and malignant hamster brain tumor, were found to contain similar migration inhibitory factor (MIF)-like activity in their supernatants. The MIF derived from the supernatants of a human lymphoid (SWB-46A) and a human non-lymphoid (HeLa) cell line were characterized and compared. The MIF produced by these cell lines were found in the present studies to be similar in many respects including: a) inhibition of cultured human lymphoid cell migration by crude supernatants, b) peak inhibitory activities in the same fractions (m.w. 10,000 to 30,000) following separation by ultrafiltration, c) similar elution profiles from Sephadex G-50 (peak inhibitory activity elutes between enzyme markers of m. w. 12,400 and 25,000), d) non-dialyzability and e) heat stability at 56°C for 30 min. The similarity found in the properties of these MIF suggests that migration inhibitory factor is not solely a lymphoid product.</jats:p

Infectious Mononucleosis: In Vitro Evidence for Limited Lymphoproliferation

Abstract The persistence of circulating leukocytes with potential for long-term in vitro proliferation was investigated in patients with heterophile-positive infectious mononucleosis. The ability to isolate long-term suspension cultures from peripheral blood with selective technics was a transient phenomenon for each patient studied, disappearing with a return of clinical and laboratory parameters toward the normal state. There was no close correlation between the ability to isolate cell lines and clinical, morphologic, biosynthetic or serologic manifestations of disease.</jats:p

Electron Microscopy of Herpes-like Particles in Lymphoid Suspension Cultures Derived from Patients with Acute Viral (Serum) Hepatitis

Herpes-like particles in cytoplasm, lysosomes, and nuclei and 220 nm endoplasmic reticulum-associated particles were observed in lymphoblastoid cell lines from circulating leukocytes of viral hepatitis patients.</jats:p

Intracellular Localization of the Migration Inhibitory Factor (MIF) in a Long-Term Human Lymphoid Cell Line

Subcellular fractions of the human lymphoid cell line PGLC-33H were obtained by N&lt;sub&gt;2&lt;/sub&gt; cavitation and differential centrifugation. The purity of the fractions was assessed by the use of the following marker enzymes: &lt;i&gt;β&lt;/i&gt;-glucuronidase for the lysosomal-intermediate fraction; a nonspecific esterase for the microsomal fraction; and LDH for the supernatant fraction. These subcellular fractions were studied for MIF activity utilizing human lymphoid cells from established lines as target cells. MIF activtiy was most consistently found in the microsomal fraction. Also, MIF activity was closely associated with the relative specific activity of esterase. No such correlation with MIF activity could be demonstrated for &lt;i&gt;β&lt;/i&gt;-glucuronidase or LDH.</jats:p