A B S T R A C T Human monocytes synthesized the third component of complement (C3) up to 5 wk in vitro. Evidence for net C3 synthesis was based on (a) incorporation of 14C-labeled amino acids into C3 protein, (b) identity of the allotype of C3 produced in vitro with that of the doner's serum C3, even in the presence of carrier C3 protein of a different allotype; (c) correspondence of electrophoretic mobility, size, and subunit structure of C3 protein produced in vitro with serum C3; (d) inhibition of C3 production with cycloheximide.Monocytes from two unrelated C3-deficient patients were studied under conditions that supported C3 synthesis by normal monocytes. Serum from each of the patients contained <1% of the normal C3 concentration, but their monocytes produced C3 at -25% of the normal rate when studied after 2 wk in vitro. The C3 produced in vitro by monocytes from one of the patients had the molecular weight of normal serum C3 and dissociated appropriately under reducing conditions. Monocytes from C3-deficient patients could not be distinguished from normals on the basis of morphology, rosetting with C3-coated erythrocytes, or rates of C2, and total protein synthesis.

The cell-mediated immune response to pigeon antigens was assessed in 12 symptomatic pigeon breeders, 14 asymptomatic breeders with precipitins, 25 asymptomatic breeders without precipitins and 10 control subjects. Significant lymphocyte stimulation by pigeon serum and/or pigeon droppings extract was obtained in 11 of the 12 symptomatic breeders but was not obtained in any of the other subjects studied. The lymphocyte response to pigeon antigens in culture is presented as the distinguishing criterion for the differentiation of symptomatic and asymptomatic pigeon breeders. This study supports a direct role for a T cell-mediated immune response to pigeon antigens in the immunopathology of pigeon-breeder’s disease.

Ihrinn a measles immunjzation camoai~n hlood sam?les were collected from 203 children before vaccination. Follow un specimens were collected from 125 children 3 ~rlcs. later and from 98 chtldren 10 mos. later. Of the 125 children with follow up study, 88 had been previously vnccinated. 10 had a I~istory of measles and 27 denied vacctnntion or illness. !kanles llAT antibody geometric nesn titers (C!ms) were 13. (day 01, 33 (3 wks.), and 23 (111 mos.). Twenty-six of the 125 llsd !!.\I titers of -5 prior to vaccination and sho!red a 24-fold antitiodv titer rise. Ig:: measles ontibodv was detected in 12 of these children after protein-A and 2-!E treatmentSwith a C'PT at 3 weeks and 10 months of El and 40 respectively. There was no history of measles exposure or vaccination in this group. Tn the remaining 14 children vith initial ttters < 5 no Kx!! antibody response was detected. and despite n &-fold increase in IlAI titer at 3 wks. (C'IT 28). the 10 aonth titer had dropped considerably (C\V 9). Ten of these 14 children had a history of previous measles vaccination. The remaining 99 children had detectable initial titers between 5 and 320. After grouping these according to their pre-booster titers, no significant cllange in Q R s was ol~served when dsv 0. 3 wk. and 10 mo. results were compared. Our study suggests that IIAT antihodv titers in children previously imnunologically stimulated against measlen are not altered significantly bv revaccination, even when the prebooster titers are low or not detectable. Monocyte chemotactic defects have previously been described in several conditions. We have noted marked defects (>2 S.D.) in one patient with chronic mucocutaneoua candidiasis and 4/29 atients with atopic dermatitis. In 8 patients on salicylate tRerspy, a mean decrease of monocyte chemotaxis of 25% was seen with salicylate levels >15 mgsX compared to a mean increase of 8% when neutrophil chemotaxia was concurrently measured. We also noted decreased monocyte chemotaxis in several seemingly normal subjects with absent delayed hypersensitivity skin tests to tetanus toxoid but normal in vitro lymphocyte transformation to tetanus. MONOCYTES FROM PATIENTS WITH GENETICTheae findings extend previous studies demonstrating maturational defects in human phagocytic cells. re-emphasize the possible role of defective monocyte chemotaxis in immunodeficient states, and suggest a possible mechanism for the anti-inflammatory effects of sslicylates. THE USE OF DIPHTHERIA AND TETANUS TOXOIDS TO ASSESS CELL-MEDIATED IMMUNITY (wI).

Phytohemagglutinin in concentrations of 0 to 800 µg/ml was used to stimulate peripheral blood lymphocytes of normal donors and responses were determined using tritiated thymidine incorporation into DNA after 68 hr incubation. A computer program was used to rank responses at each dose of phytohemagglutinin and to test for a normal distribution by the technique of probit transformation of cumulative frequencies. The procedure was repeated using logarithms, square roots, and cube roots of ranked values. Results indicated that the logarithmic function provided the closest approximation to a normal distribution over the range of the dose-response curve. These results validate the practice of plotting lymphocyte culture data on logarithmic graph paper and indicate that geometric statistics should be used to compare sets of data by methods which assume a normal distribution.