The Journal of Experimental Medicine

Mozes, Edna; Shearer, G. M.; Sela, Michael

doi: 10.1084/jem.132.4.613pmid: 5534158

SJL mice are high responders to the synthetic multichain polypeptide antigen (T,G)-Pro--L, whereas DBA/1 mice are low responders (10, 11). In order to determine whether the genetic control of immune response can be correlated with the number of antigen-sensitive precursor cells, spleen cell suspensions from normal and immunized SJL and DBA/1 donor mice were transplanted into lethally X-irradiated syngeneic recipients (incapable of immune response) along with (T, G)-Pro--L. Anti-(T, G)-Pro--L responses (donor-derived) were assayed in the sera of the hosts 12–16 days later. By transplanting graded and limiting numbers of spleen cells, inocula were found which contained one or a few antigen-sensitive precursors reactive with the immunogen. Using this method to estimate the relative numbers of such cells for the high responder SJL strain, one precursor was detected in ∼1.3 x 10 6 and ∼7.2 x 10 6 spleen cells from immunized and normal donors, respectively. In contrast, one precursor was detected in about 30 x 10 6 spleen cells from low responder DBA/1 mice, irrespective of whether the donors had been immunized. These results indicate that the genetic control of immunity to the synthetic polypeptide antigen investigated is directly correlated to the relative number of precursor cells reactive with the immunogen in high and low responder strains. Footnotes Submitted: 1 April 1970

Cudkowicz, G.; Shearer, G. M.; Ito, T.

doi: 10.1084/jem.132.4.623pmid: 4927657

Marrow cells and 5 x 10 7 thymocytes of unprimed (C57BL/6 x DBA/2)F 1 , (C57BL/10 x WB)F 1 and (C3H x C57BL)F 1 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 BDF 1 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 BWF 1 and C3BF 1 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 BDF 1 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. Footnotes Submitted: 30 April 1970

Dubey, J. P.; Miller, Nancy L.; Frenkel, J. K.

doi: 10.1084/jem.132.4.636pmid: 4927658

Coccidian oocysts resembling those of Isospora bigemina were excreted by cats fed Toxoplasma . In order to identify these oocysts with Toxoplasma infectivity a number of critical comparisons were made. The appearance of oocysts and Toxoplasma infectivity was simultaneous in the feces of 23 of 24 adult cats, 3–5 days after feeding of Toxoplasma cysts; in the feces of 4 out of 9 cats, 7–10 days after feeding of trophozoites; and in 8 out of 17 cats, 20–24 days after feeding of cat feces containing oocysts. Oocysts and infectivity were present in similar numbers, and they disappeared simultaneously from the feces of cats. Oocysts and infectivity were also observed simultaneously in the feces of 9 kittens, 1–2 days old, fed Toxoplasma cysts. Oocysts could not be separated from infectivity by filtration, by continuous particle electrophoresis, or by density gradient centrifugation. Excystation of oocysts was followed by an increase in titer of Toxoplasma infectivity. Unsporulated oocysts in fresh cat feces were noninfectious to mice, but oocyst sporulation was associated quantitatively with the development of infectivity at different temperatures and conditions of oxygenation. Maximum oocyst sporulation at 48 hr correlated with the development of maximum Toxoplasma infectivity. 1 and 2% sulfuric acid, and 2.5% potassium dichromate were found to be the best preservatives for sporulation of oocysts and for the development of Toxoplasma infectivity. Low sporulation rates in 0.1% formalin, 20% ethanol, and in water were associated with low infectivity in these reagents. Neither Toxoplasma infectivity nor oocysts developed in 0.3% formalin, 1% ammonium hydroxide, or 1% iodine in 20% ethanol. Oocysts, sporocysts, and sporozoites were stained specifically with Toxoplasma antibody in the indirect fluorescent antibody test. Typical coccidian stages, schizonts, and male and female gametocytes were found in the epithelium of the small intestine of kittens fed Toxoplasma cysts. The classification of T. gondii is discussed in relation to that of other isosporan coccidia of cats and dogs. The term " Toxoplasma oocyst" is introduced and Toxoplasma is classified in the family Toxoplasmidae of the suborder Eimeriina . The species Isospora bigemina is restricted to dogs, and I. cati to cats. I. felis and so-called I. rivolta from cats were noninfectious to dogs, and did not confer immunity to subsequent infection with I. canis and I. rivolta from dogs. Footnotes Submitted: 6 May 1970

Morse, Stephen I.; Barron, Bruce A.

doi: 10.1084/jem.132.4.663pmid: 4323778

Peripheral blood lymphocytes were isolated from normal mice and mice undergoing pertussis-induced lymphocytosis. After labeling in vitro with tritiated uridine the cells were transfused into normal or pertussis-treated mice. It was found that the lymphocytes from pertussis-treated mice entered the lymph nodes of both normal mice and pertussis-treated mice to a significantly lesser extent than did normal lymphocytes which had been transfused into either class of recipient. In addition, an interdependence of changes in the various body compartments examined was found when normal lymphocytes were injected into either type of recipient. However, when pertussis lymphocytes were injected into normal mice there was no interrelationship between the changes in the node with those in the blood, liver, lung, or spleen. In the case of pertussis lymphocytes transfused into pertussis-treated mice no interrelationship between any two compartments was observed. It was concluded that in pertussis-treated mice there is an inhibition of lymphocyte emigration which is primarily the consequence of an effect on the cell. Footnotes Submitted: 18 May 1970

Schmid, Frank R.; Roitt, Ivan M.; Rocha, Maria J.

doi: 10.1084/jem.132.4.673pmid: 5508376

Complement-mediated lysis of sheep erythrocytes coated with optimal concentrations of rabbit IgG hemolysin was inhibited by euglobulin fractions from the sera of patients with seropositive rheumatoid arthritis. That this was due to direct interaction with the IgG coat on the red cell rather than a nonspecific reaction with complement in the fluid phase was confirmed by controls using cells coated with IgM hemolysin. The inhibitory activity was recovered in purified IgM rheumatoid factor preparations and could be absorbed out with insoluble aggregated human IgG. The inhibitory potency of the rheumatoid factors correlated well with their sheep cell agglutination titers. Inhibition was not the result of physical aggregation of the erythrocytes by rheumatoid factor. Kinetic studies were consistent with the view that rheumatoid factor displaces C1q from its binding to IgG. Paradoxically, at suboptimal sensitizing concentrations of IgG hemolysin, rheumatoid factor enhances the fixation of complement. These results can be interpreted on the basis of the blockage of complement fixation by IgG and its replacement by a relatively weak direct fixation by the IgM rheumatoid factor. Thus, the interaction of RF with IgG generates only a limited ability to fix complement which, when contrasted with the fixation at suboptimal concentrations of IgG hemolysin alone, appears as net enhancement; when this is contrasted with fixation occurring with optimal concentrations of IgG, it appears as net inhibition. Footnotes Submitted: 7 May 1970

Overturf, Gary D.; Mortimer, Edward A.

doi: 10.1084/jem.132.4.694pmid: 4927659

The previously reported relationship between nephritogenicity and bacteriocine production among Group A streptococci has been examined. Using techniques comparable to the earlier study, the present study did not reveal any such relationship. Among 73 strains tested, 53% produced bacteriocines; no significant difference was noted between bacteriocines from strains isolated from cases of nephritis and those from a group of strains recovered from patients with other conditions. In addition, no correlation between type and bacteriocine production was observed. Footnotes Submitted: 29 May 1970

Bianco, Celso; Patrick, Richard; Nussenzweig, Victor

doi: 10.1084/jem.132.4.702pmid: 4101362

A population of lymphoid cells from several animal species, including man, was identified through a membrane receptor which binds sheep red blood cells treated with antibody and complement. When cells from different lymphoid organs were incubated with EAC at 37°C, only part of the lymphocytes (named CRL) bound EAC and formed rosettes, and this interaction was shown to be C3-dependent. Mouse lymphoid cells could be specifically depleted of CRL by allowing them first to interact with EAC and then submitting the mixture to ultracentrifugation in a gradient of BSA. After ultracentrifugation, a population of cells containing 95% or more of non-CRL were recovered from the upper layers of the gradient. In addition to their different abilities to bind EAC, CRL and non-CRL from mouse lymphoid organs could be distinguished by the following properties: ( a ) CRL adhered preferentially to nylon wool at 37°C in the presence of mouse serum. ( b ) After differential flotation in a gradient of BSA, a significantly higher proportion of CRL were recovered from the upper layers of the gradient. ( c ) The population of CRL contained most of the lymphocytes bearing immunoglobulin determinants on their membranes. ( d ) The distribution of CRL was quite different among lymphocytes obtained from various lymphoid organs, and they were never found in the thymus. ( e ) The membrane receptor for EAC was not detected in plaque-forming cells of mice which had been previously immunized with burro red cells. CRL and non-CRL could not be distinguished by their life span, as they were found in similar proportions among long-lived and short-lived lymphocytes from mouse peripheral lymph nodes. The function of this receptor on the membrane of certain lymphoid cells may be related to ( a ) the trapping and localization of antigen in lymphoid organs or ( b ) the localization of lymphoid cells in inflammatory sites. Footnotes Submitted: 15 May 1970

Beer, Alan E.; Billingham, R. E.

doi: 10.1084/jem.132.4.721pmid: 4927660

Free tail skin grafts or suspensions of viable epidermal cells have been placed in the atraumatized uterus of isologous rat hosts and allowed to "implant" of their own accord to study the possible uniqueness of this site for other than nature's transplants, i.e. conceptuses, and its response to unnatural grafts. Despite the presence of an intact endometrial epithelium, free skin grafts heal-in rapidly, provided that a state of estrogen excess is established at the time of transplantation. In the absence of estrogen most of the grafts failed to implant. Once established, the grafts survive indefinitely without further estrogen. However, if at any stage a state of continual estrus is established, skin epidermis migrates centrifugally from the graft perimeter invasively replacing the native uterine epithelium. The results of an analysis of the modus operandi of this estrogen-facilitated epidermal migration in utero sustain the view that the hormone acts upon the uterine stroma rather than upon the epidermal cells. When grafts of lingual mucosa or vaginal "skin" were placed in the uteri of rats maintained in chronic estrus, migration of epidermis took place even more vigorously than from tail skin. These epithelia conserved their distinctive histologic specificities indefinitely when growing as heterotypic recombinants on the alien mesenchymal stroma of the uterus. Monodisperse suspensions of epidermal cells appear to "implant" and establish small epidermal plaques in the uterus only at sites predestined to accept conceptuses. That the endocrinologic parameters for the establishment of skin grafts in the uterus are similar to those for blastocysts is suggested by the finding that both kinds of graft can become established in the same uterine horn in the absence of exogenous hormones. Footnotes Submitted: 20 May 1970

Potter, Michael; Lieberman, Rose

doi: 10.1084/jem.132.4.737pmid: 4101363

Eight IgA myeloma proteins derived from independently induced plasma-cytomas in genetically similar inbred BALB/c mice are functionally related by their binding of phosphoryl choline-containing antigens (Pneumococcus C polysaccharide or Lactobacillus antigen). Each protein resembles a single species of immunoglobulin in antibody. The proteins are characterized by highly sensitive myeloma-specific antisera prepared by immunizing mice of other inbred strains with the BALB/c myeloma proteins. Individual or myeloma-specific determinants located on Fab fragments were found on three of the proteins that were unique for that protein and did not react with any other IgA protein among over 70 tested. Remarkably, five of the proteins shared two common myeloma-specific determinants which were specific for this group of five proteins. These results suggest that the five functionally and genetically related proteins sharing the same myeloma-specific determinants might also be structurally similar. Footnotes Submitted: 21 May 1970

Biozzi, Guido; Asofsky, Richard; Lieberman, Rose; Stiffel, Claude; Mouton, Denise; Benacerraf, Baruj

doi: 10.1084/jem.132.4.752pmid: 4101364

Random-bred Swiss mice were selectively bred for 16 generations; selection was based on their agglutinin response to sheep and pigeon erythrocytes to produce a high and a low responder line. The serum levels of individual immunoglobulins differed significantly in these two lines before immunization. The differences in the levels of immunoglobulins were much more marked after immunization with pigeon or sheep erythrocytes. Greater differences between the two lines were noted in IgM and IgG levels than in IgA. Another remarkable finding was the presence of different immunoglobulin phenotypes in the two lines. The high responders were homozygous or heterozygous for heavy-chain linkage groups found separately in the prototype BALB/c and C57BL inbred strains. The low responders were homozygous for a heavy-chain linkage group not present in bred mice in the United States, but observed as a recombinant type among wild mice probably representing a crossover between the heavy-chain linkage groups of the prototype DBA/2 and NH inbred mice. Footnotes Submitted: 28 May 1970