1278

there seemed to be no family history of myopathy, so thatit would belong to the group of so-called isolated or

sporadic myopathies. On the other hand, there are well-founded doubts as to the existence of such a form of

myopathy, since heredity is considered a fundamentalelement in this disease. Consequently, it can be assumedthat in this case low absorption, not present in the

patient’s relatives, has acted as the releasing factor in thepresence of hereditary predisposition.

NELLO D’ERAMO.

ROSETTE FORMATIONIN LYMPHOCYTE CULTURES

B. P. MACLAURIN.

Department of Medicine,University of OtagoMedical School,

Dunedin, New Zealand.

SIR,-It is of great interest that Bartfeld and Juliar 1found rosettes of large transitional lymphocytes, surround-ing a large central monocytoid-macrophagic cell and pro-ducing rheumatoid factor, in cultures derived fromrheumatoid patiehts. Since these rosettes may be seenalso in vivo in lymph-nodes,2 and in vitro in lymph-nodecultures from immunised animals,3 they seem to offer auseful model, permitting closer study of antibody produc-tion to a wide range of antigens.Although Bartfeld and Juliar found no rosettes in cultures

from normal controls with the technique employed, about halfof all my controls have shown well-formed rosettes in smallnumbers. Rosette formation has also been particularly notableand frequent in cultures from patients with chronic liver diseaseand with ulcerative colitis-perhaps reflecting a persistingantigenic stimulus in these patients. I have used a 3% gelatinsolution for sedimentation of red cells 4 in the initial phase ofthe culture-since this allows a particularly good separation oflymphocytes from other white and red cells, and does notappear to have any direct and artificial stimulatory effect on thelymphocytes-in contrast to the use of phytohsmagglutinin byBartfeld and Juliar which could be criticised as introducing anon-physiological stimulus of unproven nature. Both inwashed and unwashed cultures, rosettes appear well formed at4 days, but are more striking in the unwashed cultures.Difference in technique may account for the discrepancybetween my results and those of Bartfeld and Juliar in thenormal controls. The frequency of rosettes could possiblyrelate to stimulation of macrophages by the gelatin solution.If so, it seems surprising that the effect persists in the washedculture, since macrophages are infrequent at the beginning ofthe culture. I have used a very thick smear technique whichmay avoid disrupting a proportion of the rosettes present,thereby allowing their detection when present in only smallnumbers.

Rosettes may also be formed around non-phagocytic blastcells (see accompanying figure). A series of combined culturesusing white cells from two different blood-donors was set up.There was the usual lymphoblastoid transformation in about5-10% of all cells present at 4 days.5 6 This has been regardedas having an immunological basis, and analogous in some degreeto the changes seen with tuberculin and other antigens,’ thoughpresumably representing primary rather than secondary contactwith antigen. In addition, rosette formation has often been verymuch more striking in the combined cultures than in culturesof the donors singly. Many of the rosettes have been formed bylymphocytes surrounding a blast cell rather than a macrophage,though rosettes incorporating the latter have also been obvious.Attempts have been made to demonstrate antibody formationin these combined cultures, and a more detailed article on thiswork is in preparation. The presence of rosettes around blastcells is very striking in some cultures and cannot be regarded

1. Bartfeld, H., Juliar, J. F. Lancet, 1964, ii, 767.2. Thiery, J. P. Symposium on Cellular Aspects of Immunity; p. 59.

Boston, 1960.3. Sharp, J. A., Burwell, R. G. Nature, Lond. 1960, 188, 475.4. Coulson, A. S., Chalmers, D. G. Lancet, 1964, i, 468.5. Schrek, R., Donnelly, W. J. Blood, 1961, 18, 561.6. Bain, B., Vas, M. R., Lowenstein, L. ibid. 1964, 23, 108.7. Pearmain, G., Lycette, R. R., Fitzgerald, P. H. Lancet, 1963, i, 637.

Rosette formation in combined lymphocyte cultures surrounding:(a) a lymphoblast; (b) a macrophage in the same culture withmuch vacuolisation of the central cell. (x 550, reduced by half.)

as a chance finding. In more prolonged cultures, blast frequencyincreases, but rosettes are much less obvious or are absent;so that these seem unlikely to relate merely to a simple physicalor chemical attraction between the two cell types. If their

significance is similar to that of the rosettes based on macro-phages, it seems that by this time transfer of information (or ofmessenger ribonucleic acid) to other lymphoid cells may havelargely ceased, and responsive cells are committed to trans-

formation or to antibody formation.The experiments of Professor Hardy and his colleagues

(Feb. 27) show conclusively that the degree of lymphocytetransformation in combined cultures correlates closely with thetime of skin homograft rejection when grafts are made betweenvarious pairs of cell donors. Such transformation must

therefore be regarded as reflecting an immune response.I agree with Dr. Lycette and Mr. Pearmain (Feb. 20)

that lymphoid macrophages are seen in the majority oflymphocyte cultures, but that lymphoblastoid cells onlydevelop in significant numbers in response to specificstimulation, usually of an antigenic nature. In view of therosette formation around both these cell types, particu-larly in combined cultures, it appears that both may beinvolved in initiating the sequence of events leading toantibody production.

"CRI DU CHAT" SYNDROME

SIR,- The recent appearance of several reports 1-6 andof your leading article (Jan. 2) on this syndrome promptus to describe two new cases, referred to us for chromo-somes investigation because of congenital abnormalitiesand mental retardation.

CASE 1.-This is a male, born Jan. 6, 1963, when the mother,a primigravida, was 24 and the father 27. At birth the weightwas 71/2 lb. (3400 g.) and length 20 in. (51 cm.). He was

hospitalised at 2 days because of regurgitation and cyanosiswhen feeding was attempted; a diagnosis of " dysphagialusoria " was suggested by X-ray examinations and oscillo-graphic data. The electrocardiogram and electroencephalogramwere normal. At 23 months his cry recalls the " cri du chat

"

which the parents say was more feeble at birth. He presentsmuscular hypotonia and joint hyperflexibility, and appearsmentally retarded; weight 24 lb. (11 kg.), height 32 in. (83 cm.),pubis to sole 121/2 in. (32 cm.), head circumference 171/2 in.(45 cm.); wide-spaced eyes, small epicanthic folds, low-setears, irregular teeth, high narrow palate, and slightly recedingchin. There are two small cutaneous pits symmetrically placedin the sacral region. The penis and scrotum are normallydeveloped, but the testes are undescended and are palpablehigh in the inguinal canals. The hands have crooked fifth

1. Lejeune, J., Lafourcade, J., Berger, R., Vialatte, J., Boeswillwald, M.,Seringe, P., Turpin, R. C. r. Acad. Sci., Paris, 1963, 257, 3098.

2. Lejeune, J., Lafourcade, J., de Grouchy, J., Berger, R., Gauthier, M.,Salmon, C., Turpin, R. Sem. Hop. Paris, 1964, 18, 1069.

3. Punnett, H. H., Carpenter, G. G., DiGeorge, A. M. Lancet, 1964, ii,588.

4. Dumars, K. W., Gaskill, C., Kitzmiller, N. Am. J. Dis. Child. 1964,108, 533.

5. MacIntyre, M. N., Staples, W. I., La Polla, J., Hempel, J. M. ibid. p. 538.6. McCracken, J. S., Gordon, R. R. Lancet, Jan. 2, 1965, p. 23.